The grain sizes and the number of voids between grains on each film varied according to the film synthesis method. At the low excitation fluence of 0.37 μJ cm−2, fast signal drops in TA dyanmics within 1.5 ps were observed in all perovskite films, but the signal drop magnitudes differed becuase of the variations in charge migration to trap states and band gap renormalisation. For high excitation fluences, the buil-up time of the TA signal was increased by the activated hot-phonon bottleneck, while the signal decay rate was accelerated by fluence-dependent high-order charge recombination. These fluence-dependent dynamics changed for different perovskite fabrication methords, indicating that the dynamics were affected by morphological features such as grain sizes and defects.Understanding the excited-state dynamics in perovskite photovoltaics is necessary for progress in these materials, but changes in dynamics depending on the fabrication processes used for perovskite photoactive layers remain poorly characterised. Here we report a comparative study on femtosecond transient absorption (TA) in CH With the recent extensive study of these systems, the power conversion efficiency (PCE) of perovskite solar cells (PeSCs) has explosively increased dramatically from 3.8% in 2009 to >20% since 20156. The high PCEs of PeSCs are attributed to their outstanding photo-physical properties, including the long lifetimes and diffusion lengths of photoexcited carriers and excellent carrier transport performance. These are characterised by the time scales of charge generation, recombination, and transfer dynamics assessed using ultrafast spectroscopic measurements9.Organic-inorganic lead halide perovskite semiconductors are among the most promising alternatives for third-generation photovoltaics because they show exceptional advantages of low-cost straightforward fabrication, high absorption in the visible range, small exciton binding energy, and flexibility11.One effective methodological approach to enhance the performance of solution-processed PeSCs is the fabrication optimisation of the perovskite photoactive layer, achieved by controlling the composition and/or condition of the precursor solution, the types of solvents and additives, and the processing environment. These factors for fabrication engineering are known to affect the photovoltaic performances of PeSCs by changing the uniformity of micromorphology, grain size, and crystallinity in the perovskite film3NH3I (methylammonium (MA) iodide; MAI) precursor solution by Im et al.12. Grancini et al. revealed that the crystalline domain sizes in hybrid lead-halide perovskite films depends on the fabrication procedure; thus, the dynamics of excited species including free carriers and excitons are influenced by the crystal size13. Matsumoto et al. reported alteration in the photovoltaic parameters with photodegradation-induced surface roughness14. Although the correlation between perovskite morphology and photovoltaic parameters were confirmed in these cases, others have indicated that the surface coverage of the perovskite affected the short-circuit current density (JSC) but that the effects of the morphology on the PCE were less clear15. In addition, Li demonstrated that the photoluminescence decay lifetime did not change with variations in morphology above a certain grain size16.The dependence of PCE on perovskite surface morphology was successfully demonstrated by increasing the sizes of cuboids formed using different concentration of CH17: In the study, we explored the effects of various deposition methods on the performances of solution-processed planar CH3NH3PbI3 (MAPbI3) PeSCs using single- and two-step depositions. The grain size distribution was generally similar for each perovskite, but slight differences occurred; the number of grains larger than 300 nm in the film increased in the order of perovskites named CHP (single-step deposition of the precursor solution with N-cyclohexyl-2-pyrrolidone as an additive), CBdrp , and IFF (two-step deposition including interdiffusion of the MAI precursor on PbI2 film). However, despite having the small grains, the CHP-based PeSC showed the best performance, with averaged photovoltaic parameters including a JSC of 14.31 mA cm−2, open-circuit voltage (VOC) of 0.86 V, and fill factor (FF) of 73%, leading to a PCE of 9.07%. The solar cell device including CBdrp film had a JSC of 13.80 mA cm−2, VOC of 0.78 V, and FF of 73%, leading to a PCE of 8.03%. Finally, the IFF solar cell had a JSC of 13.38 mA cm−2, VOC of 0.80 V, and FF of 67%, leading to a PCE of 7.19%17. The responses of these three perovskite films on silicon substrates to terahertz waves indicated the highest free carrier accumulation at the CHP perovskite/silicon interface18, but the photophysical properties of these perovskites were poorly known.Our previous study also demonstrated ambiguity in the relationship between morphology and device performance3 perovskite films fabricated by CHP, CBdrp, and IFF are investigated and compared using femtosecond transient absorption (TA) spectroscopy in order to examine the mechanisms underlying PeSC functionality by relating the excited-state dynamics to the film morphology. The TA spectrometer setup is briefly explained in the Supporting Information and depicted elsewhere19.Therefore, in this work, the ultrafast responses of MAPbI18, while the morphology of the CHP film mainly comprises small grains and shows complete surface coverage, larger grains and intergranular voids appear in the CBdrp and IFF films.Figure 3 perovskite films. All films show two conspicuous positive curvatures at comparable wavelengths and absorption-band edges located at ~780 nm. These similarities among the absorption spectra indicate that the energy levels, excitonic and continuum contributions to the absorption, binding energies, and band gaps are not influenced by the sample preparation methods used. The perovskite films are approximately 190 nm, 230 nm, and 330 nm in thickness for CHP, CBdrp, and IFF films, respectively17; therefore, the absorbance of the IFF film may be slightly larger than those of the CHP and CBdrp films.Figure −2 at several pump-probe delays. For short time delays, each film exhibits a broad positive band from the photo-bleaching (PB) of both the band edge and near-band-edge regions by state-filling with hot carriers20. In addition, the films also show negative TA signals at energies below the band gaps, indicating that carriers are excited to transiently unoccupied states formed by band gap renormalisation (BGR)20. As the pump-probe delays are increased, the short-wavelength tails of the PB bands are changed from positive to negative values; the PB bands are also slightly red-shifted and the negative TA signals below the band gap disappear. These features reflect the instantaneous evolution of excited energy states during hot-carrier cooling and BGR22. Because the TA spectral features of the CHP, CBdrp, and IFF films are almost identical, the TA kinetics at the PB peak was examined to obtain more details of the excited-state nature.Figure −2 ; however, the subtle differences among the carrier cooling curves of the perovskites were difficult to observe because of large deviations from the fitting model. Therefore, we simply compared the early-time dynamics of TA signals in 10% to 90% of the rise time without the fitting procedure using the Maxwell-Boltzmann distribution.As the excitation fluence is increased (i.e. carrier density is increased), phases I and II disappear from the kinetics, and the time before the TA signal maximizes is decreased to ~2 ps see Fig. . This im18 cm−3) depends on the amount of unreacted PbI2 remaining in the perovskite film21, and the conversion of PbI2 to the perovskite is known to directly affect the formation of large crystals27. Therefore, we speculate that the cooling dynamics are influenced by the crystal size; this was confirmed by sample-to-sample variability testing of early time dynamics at high excitation fluence ,(b)). Faster rising aspects in the CHP films, compared to those in the CBdrp and IFF films, were reproduced in these tests. However, the rise times of the IFF films varied from sample to sample. The largest-grained perovskites were fabricated using the IFF method, but the size formation was pooly controlled, generating broad distributions for the grain sizes and photovoltaic parameters17. Therefore, the morphological heterogeneity among the IFF films may affect the hot-carrier cooling characteristics; likewise, the shortest carrier cooling times in the CHP films can be attributed to these films having the smallest grains.By comparing the rise times of the kinetics 34 and polymers semiconducting materials (~4 × 10−9 to ~3 × 10−8 cm3 s−1)36. Because the organic polymers are low mobility materials, thus they follow Langevin model in which the high-order recombination rate is proportional to the charge carrier mobility. The reaction radius of Langevin type recombination is limited to ~1 nm because the Langevin model assumes electron–hole separation occurs within Coulomb radius40. On the other hand, non-Langevin recombination arises in some semiconducting materials in which electron-hole pairs are spatially separated40. As the perovskite system are characterised by weak correlation between the high-order recombination rates and mobility40, the perovskite can be also affected by the non-Langevin recombination. Perovskite grain boundaries govern carrier trap and recombination sites as carrier confining structures42; therefore, the spatial separation of electron-hole pairs for the non-Langevin recombination in perovskite may be mainly determined by the grain boundaries. Because the grain sizes determine the amount of boundaries and are formed in a range from several hundred nanometres to several micrometres, the reaction dimensions for high-order processes in perovskite films can be significantly increased, inducing relatively slower high-fluence-induced kinetics compared to polymer films. Therefore, more active high-order processes are anticipated in smaller-grained perovskites film than in larger-grained film. And such phenomenon was confirmed by observing faster high-fluence-induced TA dynamics in the CHP film than in the CBdrp and IFF films , which generated 35 fs pulses centred at 800 nm with a 1-kHz repetition rate. The wavelengths of the amplified beams were converted to the 400-nm pump and broad band visible probe beams using second harmonic and supercontinuum generations, respectively. The instrument response function was estimated as ~140 fs by measuring the cross-correlation of the pump and probe. The polarisations of the excitation and probe beams were set to the magic-angle configuration (54.7°). The TA experiments were performed under rough vacuum and at temperature of 293 K.The perovskite films were spin-coated on poly polystyrene sulfonate (PEDOT:PSS)/indium tin oxide (ITO) for the SEM imaging and on glass substrates for the femtosecond TA spectroscopy using previously reported methodsSupplementary Information


In this paper, we propose a face recognition algorithm based on a combination of vector quantization (VQ) and Markov stationary features (MSF). The VQ algorithm has been shown to be an effective method for generating features; it extracts a codevector histogram as a facial feature representation for face recognition. Still, the VQ histogram features are unable to convey spatial structural information, which to some extent limits their usefulness in discrimination. To alleviate this limitation of VQ histograms, we utilize Markov stationary features (MSF) to extend the VQ histogram-based features so as to add spatial structural information. We demonstrate the effectiveness of our proposed algorithm by achieving recognition results superior to those of several state-of-the-art methods on publicly available face databases. Face recognition, a typical biometric identification technology, is now recognized as an essential technology for establishing secure control. It has attracted much attention from researchers and engineers over the past decades owing to its wide range of applications in many fields, including information security, identity authentication, law enforcement, smart cards, access control systems and so forth. The entire face recognition procedure consists primarily of two operations: feature extraction and classifier design. These two steps have a substantial influence on the effectiveness and reliability of various recognition approaches. Regarding feature extraction, various face representation approaches have been discussed and studied, and all these approaches can be roughly divided into two categories: appearance-based methods and feature-based methods.Appearance-based models use transformations and statistical methods to project samples from high-dimensional space into a much lower-dimensional feature subspace to extract the holistic features to represent the face. The Eigenfaces (PCA)  and FishIn contrast to the above subspace methods that directly consider whole-face images as the input patterns, feature-based methods are based on the relationships between local facial features such as the eyes, mouth, nose, and so on. Some commonly used feature-based methods exist. In , the LocAside from the above approaches, many other techniques exist to perform face recognition, such as Sparse Representation Classification (SRC) , Linear However, most of the face representation approaches mentioned above are subject to limitations, including computational issues, and can become quite complex. Although many of the appearance-based face recognition techniques work well in controlled environment, in many real-world applications, the number of available training samples is often limited. Consequently these techniques have difficulty handling substantial amounts of facial variations, such as changes in illumination, pose, accessories and expression, as well as performing sample analysis of new classes. For example, the conventional methods PCA and LDA rely on component analysis techniques. For classification purposes, LDA is generally considered superior to PCA when sufficient training samples per individual are available , howeverA reliable algorithm called the Vector Quantization (VQ) histogram method was developed in  to extraLi et al. proposed a framework in  called MWe propose the MSR-MSF-VQ algorithm based on the original MSF-VQ algorithm. The important characteristic of this extended algorithm is that it can consider the interactions of multiple different facial image sub-regions and thus preserve the significant location structure information and the spatial relationships of the facial sub-regions in the final feature information. The extended MSR-MSF-VQ features generated by our proposed algorithm can significantly improve face recognition performance.During the process of face recognition, we can obtain satisfactory recognition results by simply transferring the comparison of two facial images to the comparison of two corresponding MSR-MSF-VQ features by using distance as a dissimilarity measure. We also make use of the advantages of the SVM classifier to further optimize the recognition performance.The rest of the paper is organized as follows. First, we review the VQ and MSF approaches and then introduce the proposed MSR-MSF-VQ algorithm in detail. Next, we present the experimental results and analysis from tests on six well-known public face databases. Finally, conclusions are drawn.This section briefly reviews the VQ and MSF algorithms.Feature extraction plays a crucial role in the face recognition process. VQ  is a widAs shown in As described in , we knowpk denote a pixel in image I. C = (cij)K×K represents the spatial co-occurrence matrix, each element of which takes the following form:p1 and p2, and cij counts the number of spatial co-occurrences for bins ci and cj.Let P = (pij)K×K derived from the spatial co-occurrence matrix C = (cij)K×K can be easily computed using Formula  and the initial distribution is π(0). The stationary distribution is an invariant measure of a Markov chain, which can be accumulated by:Suppose the state distribution after π is the stationary distribution that satisfies π = πP.Here, Finally, the complete MSF feature which includes the combination of the initial distribution defined by Formula  and the Although VQ was shown to be effective in , some roStep 1: Conduct a simple a low-pass filtering to preprocess the input facial image to reduce high-frequency noise and extract the most effective low-frequency component for face recognition.Step 2: Quantize the facial sub-region into 33 levels utilizing the VQ method.d.Step 3: Construct a spatial co-occurrence matrix based on a defined distance Step 4: Calculate the Markov transition matrix, which is derived from the spatial co-occurrence matrix.Step 5: Normalize the self-transition as the initial distribution and combine it with the stationary distribution to obtain the complete MSF-VQ feature.After obtaining the MSF-VQ features, the next step is the face recognition procedure, which is similar to the original VQ algorithm. We can obtain the final recognition results by transferring the comparison of two facial images to the comparison of two corresponding MSF-VQ features. Although the recognition results using MSF-VQ algorithm on the ORL database were reported in our earlier work  are bettwr represents the corresponding weighting factor of the MSF-VQ feature for each facial sub-region. Formula , in whicThe related experimental results and comparative analyses using MSR-MSF-VQ algorithm for face recognition are presented in the next section.In this section, to evaluate the feasibility and performance of our proposed algorithm, we carried out experiments on six standard public face databases: ORL  29], FE, FE29], d (the distance used in the co-occurrence matrix), and n (the number of transfer times) must be determined in advance. This subsection contains an analysis of how to set these parameters. We conducted experiments on the ORL face database to investigate the sensitivities of these three parameters. The ORL database  con cond  algorithm on the ORL database to select optimal values for the parameters d and n. In the first experiment, we fixed d to 1 and varied n from 10 to 100. In the second experiment, we fixed n to 50 and varied d from 1 to 6. We calculated the recognition rate for all variations. The corresponding average recognition results are shown as a function of filter size in d is fixed to 1, while n on the face recognition rate is not obvious, especially at filter sizes of 11×11 or 13×13. This result confirms that it is feasible and suitable to choose n = 50  and d =The experimental results on ORL face database demonstrated the effectiveness of the algorithm combining MSF and VQ. To more convincingly demonstrate the effectiveness of the MSF-VQ algorithm, we applied it to a larger face database called FERET  31] [38 [3831] [Our previous experimental results reported in  validated and n) by testing using a larger database than the ORL database. Our recognition results on the FERET database are shown in d and n) are not sensitive to the training database. Therefore, in the next set of experiments based on other face databases, the parameters d and n are fixed and set as they were in this work. Next, we vary the factors F1, F2 and F3. The experimental results are listed in Before validating the effectiveness of our new proposed MSR-MSF-VQ algorithm, we investigated the impacts of factors such as image size (F1), similarity measures (F2), and directions of the occurrence matrix (F3).These parameters play essential roles in our algorithm; consequently, to obtaining the optimal parameter values would facilitate our future work. Moreover, we also conducted experiments to further investigate the sensitivity of the parameters  that is widely used in computer vision community—has achieved promising results in face recognition recently, we compared our proposed algorithm with some recent works based on CNNs to further validate the effectiveness of our proposed algorithm. We conducted extensive experiments based on CNNs, still using the FB task in the FERET database for face recognition.Because we lacked large-scale datasets to train our own deep learning model, we used pre-trained models and CNN architectures and then fine-tuned the parameters on our own dataset. We mainly chose two CNN architectures (AlexNet and CenterlossNet) for our experiments. AlexNet  is one oTo compare the performance of our proposed algorithm with the methods based on CNNs, for the face recognition process, we not only used the previously introduced Manhattan distance as the similarity measure to obtain the recognition results but also adopted the Support Vector Machine (SVM)  to optimFinally, we compared the average execution time of our proposed algorithm with the times of the different approaches mentioned in The AR face database , 41 contFor our experiments, we selected 1,300 images of 100 individuals —13 different images for each subject. All the images are greyscale and cropped to 90×120 pixels based on two eye centre coordinates. To verify the effectiveness of our algorithm, we designed two test sets (the first comprised 300 scarf-occluded images and the second comprised 300 sunglasses-occluded images) and utilized the remaining seven images for each subject to create the training set. Next, we conducted experiments to demonstrate the effectiveness of the proposed MSR-MSF-VQ algorithm under partial occlusion conditions using the same training and test sets. These experimental results clearly reflect that using whole-face MSF-VQ features is not a good strategy for face recognition and leads to uncompetitive recognition performances. However, by deploying an appropriate division strategy and using the combined MSF-VQ features for face recognition, the recognition performance improves. The satisfactory performance achieved on the AR face database confirms that our MSR-MSF-VQ algorithm is robust to partial occlusions.To further explore the performance of the MSR-MSF-VQ algorithm under facial expression and illumination variations, we applied it to the Yale database , which cFor our first experiment, we randomly chose six images as gallery sets and the remaining five images as probe sets for each person, similar to   images of each person from the Yale face database as the training set and employed the remaining 11-m) images for testing. For each m we repeated our face recognition experiments 50 times using the MSR-MSF-VQ algorithm, and calculated the mean of the 50 results. The corresponding experimental graph of our proposed algorithm compared with LSHOG   and HOG 1-m imageSome additional experimental results on the Yale-B face database are provided in this section. In contrast to the Yale face database, the Yale-B face database , 35, 52 In our first experiment, we select Subset 1, including 7 images for each person as the gallery set (the images of Subset 1 were acquired under good illumination conditions) and randomly choosing facial images from the remaining four subsets as the probe set, which is the same approach as . We compIn our second experiment, the images with the most neutral light condition (“A+00E+00”) are used as the gallery set, and images from Subsets 1–5 are randomly chosen as the probe set, as in . We compFrom the experimental results listed in In summary, the substantial comparative analysis of our proposed MSR-MSF-VQ algorithms with several state-of-the-art methods on three standard face databases performed in this work, clearly reflect the feasibility and effectiveness of the MSR-MSF-VQ algorithm under challenges of varying facial expressions, pose and illuminations. We can attribute our algorithm's satisfactory recognition performance to the extended vector quantization histogram features (the MSR-MSF-VQ feature), which not only contain the spatial structural information but also consider the significance of location information and the interactions between different facial sub-regions.Finally, we conducted additional experiments on the well-known large-scale CAS-PEAL-R1 face database , 37. ThiThe optimal accuracy recognition rate of different approaches and our proposed algorithm for the three probe sets from CAS-PEAL-R1 face database as described above are listed in Total Variation based Quotient Image model (TVQI) . This isThe TV_L1 and TV_L2 models  in INM  (INM useAs shown in In this paper, an improved face recognition algorithm called MSR-MSF-VQ was proposed. The main characteristic of the MSR-MSF-VQ model is that it captures spatial structural information to overcome the limitation of VQ histograms. Moreover, it also incorporates location information and the spatial interactions between facial sub-regions into the identification features, which improves the facial recognition performance. The proposed method was evaluated on five well-known face databases and comparisons were made with several state-of-the-art algorithms. Our algorithm's satisfactory recognition performances demonstrate its robustness for face recognition.Although our proposed algorithm achieves excellent recognition rates using the extended VQ histogram features during face recognition, more work need to be done in the future. There are two directions worth exploring to further optimize our algorithm. First, the VQ histogram is utilized in this paper, and it is a reliable facial feature representation for face recognition; however, other histogram-based features such as LBP , HOG 1010, and s


Sequence similarity searches have been widely used in the analyses of metagenomic sequencing data. Finding homologous sequences in a reference database enables the estimation of taxonomic and functional characteristics of each query sequence. Because current metagenomic sequencing data consist of a large number of nucleotide sequences, the time required for sequence similarity searches account for a large proportion of the total time. This time-consuming step makes it difficult to perform large-scale analyses. To analyze large-scale metagenomic data, such as those found in the human oral microbiome, we developed GHOST-MP , a parallel sequence similarity search tool for massively parallel computing systems. This tool uses a fast search algorithm based on suffix arrays of query and database sequences and a hierarchical parallel search to accelerate the large-scale sequence similarity search of metagenomic sequencing data. The parallel computing efficiency and the search speed of this tool were evaluated. GHOST-MP was shown to be scalable over 10,000 CPU  cores, and achieved over 80-fold acceleration compared with mpiBLAST using the same computational resources. We applied this tool to human oral metagenomic data, and the results indicate that the oral cavity, the oral vestibule, and plaque have different characteristics based on the functional gene category. Most microbes are difficult to isolate and cultivate . The metIn such studies, environmental samples are characterized by the abundance of ortholog groups ,6,7. StuTo estimate the abundance of ortholog groups in environmental samples, sequence similarity searches have been used to identify ortholog groups of each sequence in the metagenomic data. In metagenomic studies, the query sequences often have no close homologs in database sequences. This necessitates sensitive search methods, such as BLASTX , which sHowever, searching with BLASTX requires a long calculation time, making it difficult to perform large-scale analyses . For example, each BLASTX search takes about one minute with a single query of a nucleotide sequence of approximately 100 bases and a reference sequence database such as KEGG GENES  or NCBI The Human Microbiome Project (HMP) has already achieved large-scale functional analyses, albeit with a markedly reduced reference database ,7. Some Two approaches have been developed to accelerate sequence similarity searches. The first uses a search algorithm with a sophisticated database index, such as a hash table  or a sufAlthough both approaches accelerate the similarity search process, the acceleration of only one approach is insufficient for large-scale analyses. We typically require 10,000-fold acceleration compared with a single BLASTX run with one CPU core for the functional annotation of shotgun sequencing data within several hours. Search algorithms with database indexes are not fast enough. An ideal parallel search could achieve 10,000-fold acceleration using 10,000 times the computational resources, but those means are not easily available. Thus, a method that combines the advantages of both approaches is needed.In this study, we developed a new massively parallel sequence similarity search tool for large-scale metagenomic sequencing data, such as the human oral microbiome. The system consists of a parallel sequence similarity search on a massively parallel distributed memory system, named GHOST-MP. This enables the analysis of large-scale metagenomic data consisting of hundreds of sets of environmental sequencing data. GHOST-MP employs both a fast search algorithm and parallel computation to accelerate similarity searches for metagenomic sequencing. To demonstrate the applicability of GHOST-MP to large-scale metagenomic functional analyses, we first present the search speed and scalability of GHOST-MP on two massively parallel computing systems. We then show the results of large-scale sequence similarity searches of actual metagenomic data. GHOST-MP achieved faster sequence similarity searches than mpiBLAST, enabling large-scale functional analyses to be performed within a short period of time. Then, we performed metagenomic analysis of human oral microbiome based on a fullset of functional gene reference using GHOST-MP. The results indicated that oral cavity, oral vestibule, and plaque have different characteristics.http://www.bi.cs.titech.ac.jp/ghostmp/.The GHOST-MP program is implemented in C++, and is available under the BSD (Berkeley Software Distribution) License from Before performing the analysis of the human oral microbiome, we evaluated the search speed of GHOST-MP, which was measured on two systems: TSUBAME 2.5 at Tokyo Institute of Technology, and the K computer at RIKEN Advanced Institute for Computational Science, using human oral metagenomic shotgun sequencing data queries and the KEGG GENES amino acid sequence database. The scalabilities were evaluated in weak and strong scaling experiments. In the weak scaling setting, the number of query sequences per CPU core was fixed as the number of cores increased. This scenario evaluates how a large problem can be efficiently dealt with. In the strong scaling setting, the total number of query sequences was fixed to evaluate how fast the method could process the same amount of data. On TSUBAME 2.5, the search speed of mpiBLAST (version 1.6.0) was also measured and compared with that of GHOST-MP using human tongue dorsum metagenomic data (SRS078182). Parts of the query sequences  were used for evaluation on TSUBAME 2.5 due to limitations in computational resources. mpiBLAST was not evaluated on the K computer because it encountered a bus error on this system. This error could have been caused by unaligned memory access, as the processor in the K computer does not allow such access.We further evaluated the scalability of GHOST-MP on the K computer to investigate its performance on a massively parallel computing system. To evaluate the aforementioned scalability, we used 107 samples of buccal mucosa metagenomic data because the K computer has a larger number of CPUs that can carry out a computational process for a larger dataset necessary for evaluation. Generally, it is more difficult to achieve good scalability on larger systems because the master process must communicate with more workers. However, GHOST-MP scaled well up to over 10,000 CPU cores in reference to both criteria . GHOST-MTo demonstrate the applicability of GHOST-MP to large-scale functional analysis of metagenomic data, we applied the functional analysis workflow to healthy human oral metagenomic data consisting of 381 samples taken from eight oral sites, with approximately 18 billion sequence reads . Throughhttp://www.hmpdacc.org). Reads from the human genome, duplicate reads, and low-quality bases were removed from these data by HMP DACC in advance. Identifiers and details of human oral samples data are listed in Human oral metagenomic sequencing data were downloaded from the HMP Data Analysis and Coordination Center  is the sequence of Eukaryotes. The third step maps the read sequences to the annotated sequences in the KEGG GENES amino acid sequence database (released in July 2012). The second step and the third component perform sequence similarity searches using GHOST-MP with the PAM 30 substitution matrix, with the gap opening penalty of −9 and the gap extension penalty of −1. These steps account for most of the computation time in this workflow. The search results are considered as hits if the alignment score and sequence identity are above 40% and 70%, respectively. The fourth one calculates the relative abundances of orthologous groups (KEGG Orthology entries) in the data. The number of hits of each gene in an orthologous group is summed up with normalization using its gene length and the number of hits of universal single-copy genes .The TSUBAME 2.5 supercomputer consists of 1408 thin compute nodes. Each compute node has two Intel Xeon X5670 processors  and 54 GB of main memory. The nodes are interconnected with a full bisection-bandwidth fat-tree network. Each compute node has three NVIDIA Tesla K20X GPU accelerators, but the accelerators were not used in this study. The K computer consists of 82,944 compute nodes. Each compute node has a SPARC64 VIIIfx processor  and 16 GB of main memory, and is connected to a six-dimensional mesh/torus network. We used up to 1536 CPU cores (128 nodes) and 49,152 CPU cores (6144 nodes) to measure the scalability of GHOST-MP on TSUBAME 2.5 and the K computer, respectively.GHOST-MP uses the GHOSTX  search aThe main search algorithm consists of the following steps: (1) search for alignment candidates with the suffix array; (2) perform ungapped extension of the candidates; (3) filter out overlapping candidates; and (4) perform gapped extension of the candidates. Query nucleotide sequences are treated as amino acid sequences throughout the search procedure, with translations over six possible reading frames for a sensitive search with an amino acid substitution matrix.GHOST-MP adopts a two-level hierarchical parallelization. The sequence similarity search is parallelized by MPI at the inter-node level and by OpenMP at the intra-node level. The original GHOSTX algorithm only provides a parallel similarity search with OpenMP. Thus, we could not execute GHOSTX on distributed-memory systems (inter-node), which account for a large portion of current supercomputers in use, because OpenMP only provides parallelization on shared-memory systems (intra-node). Thus, GHOSTX could not take advantage of the large computational power of supercomputers. The hierarchical parallelization has two advantages compared with MPI-only parallelization, described as follows.(1)Hierarchical parallelization largely reduces the memory use of worker processes because it enables the sharing of common data in intra-processes, such as database sequences. The size of database sequences and their index often exceed the memory size in massively parallel environments. Index size is the product of the length of the concatenated database sequence and the size of the index pointing to the corresponding position in the concatenated database sequence. For example, when KEGG GENES  is used as an amino acid sequence database, the total size of the database sequence and its suffix array with auxiliary data is approximately 20 GB. If we use MPI for both inter- and intra-node parallelization, each individual process, even those within the same computing node, has to store the same database. In current massively parallel computing systems, nodes rarely have sufficient memory to store multiple copies of the database and its index. To reduce memory use, it is possible to split the database by assigning different partitions to each intra-node process. However, searching by this approach is inefficient for two reasons. First, splitting the database requires an additional merging step to combine the most similar hits for the same query sequence. Second, searching for alignment candidates with a split database requires more CPU time than searching with an unsplit database because the search time for alignment candidates with a suffix array is proportional to the logarithm of the database size.(2)Hierarchical parallelization can also lead to scalable parallel searching. Since the communication between the master and the workers involves MPI point-to-point communication, parallel searches with a smaller MPI process reduce the number of communications sent from the workers to the master compared with searches in nonhierarchical parallelization .Details of this two-level hierarchical parallelization of GHOST-MP are as follows. At the inter-node level, GHOST-MP adopts a master–worker model. Communication between the master process and the worker process is implemented with MPI. Firstly, query sequences are split into the same number of chunks as the number of worker processes. The master process assigns a sequence chunk to each worker process as a task. At the intra-node level, similarity searches are parallelized with OpenMP. Query sequences in a chunk are subdivided into more specific tasks. These subdivided tasks are put into a queue, and each OpenMP thread sequentially dequeues a task from the queue using a lock. Finally, each worker process writes search results to a clustered file system and reports results to the master process .We have developed GHOST-MP, a massively parallel sequence similarity search tool for metagenomic data to allow for large-scale analyses of metagenomic data. GHOST-MP uses a search algorithm with suffix arrays, and its parallel similarity search procedure is implemented using a two-level hierarchical model. GHOST-MP achieved over 80-fold acceleration compared with mpiBLAST, and exhibited almost a linear increase in speed with an increase in the number of CPU cores on TSUBAME 2.5. GHOST-MP also scaled well to over 10,000 CPU cores on the K computer. The fast search ability of GHOST-MP enabled us to perform a large-scale sequence similarity search of 381 human oral microbiome metagenomic sequencing data (18 billion reads) against the whole database of KEGG GENES (8.6 million amino acid sequences) on a massively parallel computing system. This massive data analysis indicated characteristics of functional gene in the microbial community of three human oral parts.


This work demonstrates for the first time a novel and effective technique to assess molecular diffusion at the nano-scale across sub-nano-porous materials by probing molecular flexibility across crystal lattice and single cell units.The fabrication of molecular gas sieving materials with specific affinities for a single gas species and able to store large quantities of materials at a low or atmospheric pressure is desperately required to reduce the adverse effects of coal and oil usage in carbon capture. Fundamental understanding of the dynamic adsorption of gas, the diffusion mechanisms across thin film membranes, and the impact of interfaces play a vital role in developing these materials. In this work, single gas permeation tests across micro-porous membrane materials, based on metal organic framework crystals grown on the surface of carbon nanotubes (ZiF-8@CNT), were performed for the first time in-situ at the Australian Synchrotron on the small angle X-ray scattering beamline in order to reveal molecular sieving mechanisms and gas adsorption within the material. The results show that specific chemi-sorption of CO Diffusion mechanisms across micro- and nano-porous structures have been demonstrated to exhibit non-conventional behaviours related to the confinement, sieving, or surface diffusion of gas or liquid molecules at the nanoscale across the pores of various materials ,2. New mSome of the most promising micro- or nano-porous materials, whose pores act as individual channels for specific diffusion, include aligned carbon nanotubes, ordered metal oxide monoliths, and metal organic frameworks (MOFs) . These hThe dynamic nature of the gas uptake is affecting permeation and selectivity and the lack of understanding interactions at the sub-nanoscale is thus limiting the design of efficient MOF separation materials. Monitoring diffusion process in situ is challenging due to the fast kinetics of gas diffusion. Unfortunately, the very early events occurring within seconds cannot be followed by classical X-ray diffraction. Advanced characterization techniques to reveal dynamic adsorption of gas and diffusion mechanisms across thin film membranes are required to study the impact of interfaces for diffusion mechanisms.It is this initial phase that now becomes accessible by combining in-situ small angle X-ray scattering (SAXS) experiments with a sub-second time resolution. Recently, the influence of solvent adsorption on materials crystallinity and swelling was also revealed by SAXS ,10, demoHere, ZiF-8 crystal membranes, with a well-defined and narrow pore size distribution, were prepared through a simple solvo-thermal synthesis and seeded across the surface of CNTs by combining methanol solutions of zinc salts, imidazolate rings, and functionalized CNT bucky-papers (BPs) (ZiF-8@BP)  at room As seen in 2 permeation was shown to be hindered compared to its theoretical Knudsen diffusion factor, which may be attributed to the enhanced enthalpy of adsorption of CO2 on ZiF-8 compared to noble or noble-like gases . In . In 9]. In a typical in-situ dead-end gas permeation test, the membranes were sealed into a stainless steel module, prior to being put in vacuum on both up- and down-streams. After complete evacuation of the remaining adsorbed gases, SAXS pattern acquisition started immediately prior to pressurizing the up-stream line. This strategy allowed for the control of both transmembrane pressure and degassing conditions. 2, CO2, Ar, and Xe at a 101-kPa feed to permeate transmembrane pressure difference and 25 °C in a single gas permeation rig . The feed vessel was then isolated from both the vacuum and membrane holder, and filled to the target pressure at 101 kPa at ±0.5 kPa with analytical grade, dust-free, de-humidified gas. Prior to testing, the membrane was conditioned for 1 h under vacuum to desorb any remaining water moisture or strongly adsorbed gas. For testing, the permeate side was isolated from the vacuum. The feed vessel was opened to the permeate vessel via the membrane, and the pressure rise in the permeate vessel was monitored over time until equilibrium was reached. The feed pressure remained essentially constant due to its much larger volume compared to that of the permeate vessel. The membrane permeance was then determined from the pressure rise as a function of time 4. All the tests were performed at controlled temperature (22 ± 1 °C).Single gas permeation tests were performed with He, Ntion rig  2]. The. The2, CScanning electron microscopy (SEM) was performed on a Zeiss Supra 55 VP FEG Scanning Electron Microscope . Micrographs were taken at a 3.5-mm working distance and under a 5-keV beam voltage (aperture 20 mm). The samples were carbon-coated with a 1–2-nm-thick layer.−1).SAXS experiments were performed on the SAXS/WAXS beamline at the Australian Synchrotron under the grant M5826 in March 2013. The samples were mounted within a specially designed stainless steel gas tight module with two parallel quartz windows reinforced with Kapton tape, as presented in This paper demonstrates for the first time insights in the specific single gas permeation experiments, correlated to scattering data to evaluate both the physi- and chemi-sorption of gas molecules. This novel approach opens the door to the design of the visualization of molecular diffusion at the nanoscale with SAXS analysis and to the probing of the flexibility and compressibility of porous micro-structures single unit crystals to gas permeation behaviours. The concept and method proposed here could also be applied to the assessment of the properties of MOF crystals and grain boundaries beyond the sole scope of separation, for sensing and storage, by providing insights on the materials thermal, mechanical, and chemical stability under specific stress.


Median energy percentages (E%) from protein, fat and carbohydrates were within the recommended intake ranges, except the level of saturated fats (12–13 E%). Median intakes of almost all micronutrients were above the recommended daily intakes. Most of the infants consumed iron-enriched products (81%) and received vitamin D supplements (84%). The median intakes of iron and vitamin D were significantly higher among infants receiving iron-enriched products and vitamin D supplements compared to infants not receiving such products (p < 0.001). The findings indicate that the food and nutrient intake of this group of infants in general seems to be in accordance with Norwegian dietary recommendations. Foods rich in iron and vitamin D supplements were important sources of the infants’ intake of iron and vitamin D and should continue to be promoted.The aim of the present paper was to describe food and nutrient intake among 12-month-old Norwegian-Somali and Norwegian-Iraqi infants, with a focus on iron and vitamin D intake. A cross-sectional survey was conducted from August 2013 through September 2014. Eighty-nine mothers/infants of Somali origin and 77 mothers/infants of Iraqi origin residing in Eastern Norway participated in the study. Data were collected using two 24-h multiple-pass recalls. Forty percent of the Norwegian-Somali infants and 47% of the Norwegian-Iraqi infants were breastfed at 12 months of age ( The first two years of a child’s life are particularly important as this is a period of rapid growth when nutritional needs are high ,2. KnowlConsequently, compared to infants of Norwegian-born parents, less is known about the food and nutrient intake of infants of immigrant parents in Norway. However, some previous smaller studies of Norwegian immigrant children have shown some potential nutrition challenges, such as high prevalence of iron and vitamin D deficiencies and a relatively high added sugar intake ,8,9. It To address the paucity of data on food and nutrient intake and infant feeding practices among Norwegian children with immigrant backgrounds, the InnBaKost study was initiated in 2012. Information on breastfeeding and complementary feeding practices among 6-month-old Norwegian-Somali and Norwegian-Iraqi infants was recently published . The preA cross-sectional survey was carried out from August 2013−September 2014. Mothers born in Somalia or Iraq and living in Oslo, Akershus or Buskerud were eligible for inclusion. These two immigrant groups were chosen, as they are the two non-Western immigrant groups in Norway with the highest number of births per year [Mothers who participated in the InnBaKost survey of 6-month-old infants  were conn = 13) only completed one single 24-h recall. For mothers who were unable to meet in person, the interview was conducted over the telephone. Of all the participants, 3% (n = 5) had both interviews conducted over the telephone, while 4% (n = 7) had one of the two interviews conducted over the telephone. The interviews were conducted at a time and place chosen by individual mothers. The average time between the two 24-h recalls was 2 weeks. For 7% of the participants, there were more than 4 weeks between the two interviews. Approximately 78% of all the dietary recalls were collected for intakes on weekdays and 22% were collected for intakes on weekends among Norwegian-Somali infants, and the numbers were 83% and 17%, respectively, for Norwegian-Iraqi infants. In both groups, over 85% of the recall days were reported as representative of the usual daily dietary intake of the child. Each mother who completed the two 24-h recalls received a voucher for a baby shop worth approximately US $25.To collect data on the food intake of the 12-month-old infants, two 24-h multiple-pass recalls were conducted face-to-face as closely as possible to the child’s 12-month birthday. Eight trained female fieldworkers speaking the relevant language performed the interviews in Somali, Arabic, Kurdish or Norwegian. A total of 8%  approved the study, and informed consent was obtained from all the participating mothers.The 24-h multiple-pass recall method was used to collect data on the 12-month-old Norwegian-Somali and Norwegian-Iraqi infants. The method was first developed and pilot tested on 12 Somali-born and Iraqi-born mothers from January to June 2013 .Briefly, in this dietary recall method, the mothers were to be interviewed twice about the exact food and beverage intake of their children during the preceding 24 h. A 24-h period was defined as from the time the child woke up the previous day until the time the child woke up the day of the interview.The dietary recall was divided into three passes. In the first pass, the mothers were asked to report everything that their children had consumed the previous day, including during the night. Each breastfeeding occurrence was also to be reported. In the second pass, mothers were asked to provide additional detailed information about each item of food and drink consumed by the children. This included type of product, brand names, cooking methods, amounts and leftovers. For homemade dishes, the mothers were asked for the recipes, and the list of ingredients was recorded. The third pass was a review of the recall, and the mothers were given the opportunity to provide any additional information regarding the children’s food and drink consumption. During the last pass, the field workers were also instructed to prompt for information about foods and drinks not mentioned that were considered to be easy to forget, such as snacks, fruits, water, juices and supplements, which the field workers read from a list.Spedkost booklet [Norkost booklet [Two photographic booklets previously used in Norwegian national dietary surveys, were utilized during the interviews as an aid to estimate portion sizes. The  booklet  containi booklet  containiA picture library containing 405 pictures divided into 19 folders on an iPad was used to help identify the types of foods/drinks/products given to the children. The development of the picture library has been described in more detail elsewhere .A questionnaire with 19 questions on five topics was used to collect additional information about the infants. The questions related to breastfeeding , the age of introduction to various foods and drinks, whether the infant had any allergies/intolerances, the use of dietary supplements and arenas for receiving infant nutrition information.In Norway, healthcare personnel routinely measure the length and weight of children during regular check-ups at children’s health clinics, including at 12 months of age. Participating mothers were asked to bring their infant’s health cards to the interview in order to record these data. Other background characteristics, such as infants’ gender, mothers’ age, mothers’ age when they immigrated to Norway, number of children, parental education levels and fathers’ origins, were already provided from the 6-month survey. The same questions were asked of newly recruited mothers. All mothers were also asked to provide information on current work status and person/place in charge of day-care for the infants. When possible, other persons in charge of the day-care of the infant during the recall days were consulted on the infants’ dietary intake during those hours.Information from the 24-h recalls was manually coded by nutritionists. All foods and beverages consumed by each child were converted into grams of edible portions. For recipes, a modified version of the summing method was applied to calculate the intake of each ingredient . A breasn = 12) did not differ from those who completed two face-to-face 24-h recalls and were therefore included in the analyses. Mothers who only completed one 24-h recall were also included.Data from the questionnaire and background characteristics were manually entered into the statistical software package IBM SPSS Statistics version 22.0. Data about the food and nutrient intakes estimated from KBS were transferred to SPSS. All data were further processed and analysed in SPSS. Energy intake information acquired during the telephone interviews  and were tested using a Mann-Whitney U test. Categorical variables were tested using a Chi-square test.Iron intake was compared between infants receiving and not receiving dairy products and between infants receiving and not receiving iron-enriched products. The intake of dairy products and the intake of iron-enriched products were tested by different background characteristics. The intake of vitamin D was compared between infants receiving and not receiving vitamin D supplements. The intake of vitamin D supplements was tested by different background characteristics. The data did not adhere to a normal distribution, and continuous variables are presented as median and 25th and 75th percentiles (Pp = 0.001) but not for weight-for-height  compared to the Norwegian-Iraqi infants. The Somali-born mothers were younger , had lived in Norway for a longer period of time  and a higher percentage were working at the time of interviewing  compared to the Iraqi-born mothers. A higher proportion of the Iraqi-born mothers had higher education compared to the Somali-born mothers .Selected characteristics of the infants and their parents are presented in p = 0.414). The median breastfeeding frequency among those breastfeeding was 4.5 times a day in both groups.At 12 months of age, 40% of the Norwegian-Somali infants and 47% of the Norwegian-Iraqi infants were breastfed . The median energy percentages (E%) from protein, fat and carbohydrates were within the recommended intake ranges in both groups; however, the intake of saturated fats was above the recommended upper level of 10 E%. The intake of added sugar, on the other hand, was below 5 E% in both groups.The average energy and nutrient intake from the 24-h recalls are shown in The main sources of saturated fat intake in the total diet of the Norwegian-Somali infants were cow’s milk (which contributed with 22%), breast milk (22%), commercial infant cereals (9%) and cheese (8%) (data not shown). The main sources of saturated fats among the Norwegian-Iraqi infants were breast milk (23%), meat and meat products (11%), cow’s milk (9%) and cheese (9%). Yoghurt was the main source of the added sugar intake among both the Norwegian-Somali and Norwegian-Iraqi infants (38% vs. 23%).The median intake of all micronutrients, except iron and niacin in both groups and zinc among Norwegian-Somali infants were above the RI.p = 0.574, data not shown). p = 0.015). Intakes of iron did not differ significantly between infants receiving dairy products compared to infants not receiving dairy products. However, the median intake of iron was significantly higher among infants receiving iron-enriched products (8.1 mg/day) compared to infants not receiving iron-enriched products . Neither intake of dairy products nor intake of iron-enriched products differed significantly between genders, according to mothers’ ages, number of years lived in Norway, education level, current work status or number of children.The main sources of dietary iron were commercial infant cereals , iron supplements (13% vs. 9%), infant formula (10% vs. 19%) and bread and other grain products (10% vs. 8%). During the recall days, 6% of the Norwegian-Somali infants and 8% of the Norwegian-Iraqi infants received supplements containing iron (p < 0.001) The median (P25–P75) intake of vitamin D among those receiving vitamin D supplements was 14.5 (10.8–18.1) μg/day compared to 4.1 (1.5–7.6) μg/day among those not receiving vitamin D supplements (p < 0.001). The intake of vitamin D supplements did not differ significantly between genders, according to mothers’ ages, number of years lived in Norway, education level, current work status or number of children.Vitamin D supplements comprised more than half of the vitamin D intake in both groups . Other sources of vitamin D were commercial infant cereals (19% in both groups), infant formula (7% vs. 17%) and fish and fish products (6% vs. 3%) among Norwegian-Somali and Norwegian-Iraqi infants, respectively. During the recall days, a total of 84% of the infants had received vitamin D supplements. Significantly more among the Norwegian-Somali infants compared to the Norwegian-Iraqi infants had received vitamin D supplements during the recall days  to assess the infants’ dietary intake at 12 months of age , while tThe energy intake among both Norwegian-Somali and Norwegian-Iraqi infants was lower than the mean intake of 5100 kJ reported in the national dietary survey, which only reported the energy and nutrient intake of non-breastfed infants . The aveThe median E% of protein, total fat and carbohydrates were all within the recommended intake ranges . SaturatIron deficiency has been reported to be prevalent among both immigrant and non-immigrant children in Europe ,31,32, hIn the present study, we found no significant differences in iron intake among infants who consumed dairy products compared to those who did not consume dairy products. There were no significant differences among those who consumed more than 500 g/day of dairy products compared to those who consumed less. Still, high consumption of cow’s milk is not recommended as it may inhibit the iron absorption . Higher The intake of vitamin D exceeded the recommended levels for both Norwegian-Somali and Norwegian-Iraqi infants. Severe vitamin D deficiency has been reported to be prevalent among 6-week-old infants of immigrant backgrounds in Norway who did not receive vitamin D supplements . In the Two very specific subgroups of the Norwegian population were chosen for the study, which is an important strength of the survey. According to lists from the National Population Register, the participating Norwegian-Somali and Norwegian-Iraqi infants accounted for approximately 19% and 27%, respectively, of all Norwegian-Somali and Norwegian-Iraqi infants who turned 12 months old during the recruitment period in the three Norwegian counties included. Recruitment challenges are widely reported in studies among immigrant populations , and wasIn general, the dietary assessment of infants can be complicated by the fact that dietary habits change rapidly in infancy. A review by Burrows et al. has indicated that weighed food records may provide the best dietary estimates for younger children from 0.5 to 4 years old . HoweverAlthough the macronutrient composition may reflect the true dietary practices of the two immigrant groups, reporting errors such as underreporting or overreporting may contribute to apparently low or high intakes of certain foods . For infIn addition, biochemical indicators of iron and vitamin D status were not measured in the present study, which is necessary in order to assess the infants’ iron and vitamin D status.The findings of this study indicate that the food and nutrient intake of Norwegian-Somali and Norwegian-Iraqi infants in general seems to be in accordance with the Norwegian dietary recommendations. The intake of dairy products was generally higher among Norwegian-Somali infants compared to Norwegian-Iraqi infants, but dairy product intake did not seem to affect iron intake. Iron-enriched products and vitamin D supplements were important sources of the infants’ iron and vitamin D intake. Vitamin D supplements and foods rich in iron should continue to be promoted. Infants with immigrant backgrounds are excluded from the Norwegian national dietary surveys, and the present study contributes with information about food and nutrient intake among two of these groups living in Norway. More research to investigate infant feeding practices among immigrant groups in Norway is needed.


An increasing number of perinatally HIV-infected women (PHIV) are reaching adulthood and becoming pregnant. Most PHIV women have been exposed to a high number of antiretroviral regimens, and they may have difficulties to achieve viral suppression. Psychosocial problems are not uncommon and could be an important barrier for treatment adherence. The effects of chronic HIV infection and long-term exposure to antiretroviral treatment of PHIV women cause concerns on the developing fetus. The aims of this study were to describe the prevention of mother-to-child transmission strategies in PHIV women and the infant outcomes in the Madrid Cohort of HIV-infected mother-infant pairs.All PHIV pregnant women registered in the Cohort that gave birth from 2000 to 2015 were included in the study.Twenty-eight pregnancies in twenty-two perinatally infected women were registered. Most women were Caucasian and heavily treatment-experienced. Nine cases (32.1%) were at high risk of HIV mother-to-child transmission. Maternal HIV-1 viral load was detectable close to delivery in four women (14.3%). The management of these cases was described, and the treatment strategies were discussed. None of the newborns acquired HIV infection. Eight infants (28.6%) were small for gestational age.This study included a large series of pregnancies among PHIV women attended according to a youth-centered care model. The challenges in the management of this population by health-care providers were described. Specific strategies to minimize perinatal transmission risks should be addressed in future collaborative studies. In Western European countries the efforts in the prevention of mother-to-child transmission of HIV (PMTCT) have led to an important reduction in the rates of new infections in children. –4 Cases An increasing number of perinatally HIV-infected women (PHIV) are reaching adulthood and becoming pregnant. Most PHIV women have been exposed to a high number of antiretroviral regimens during pediatric care, and when they become pregnant, they may have difficulties to achieve viral suppression close to delivery. –10 Psych-infant pairs.The aims of this study were to describe the PMTCT strategies in PHIV women and the infant outcomes in the Madrid Cohort of HIV-infected motherThe Madrid Cohort of HIV-infected mother-infant pairs is a multicenter, prospective and observational study of HIV-1 infected women and their children. Since 2000, mother and infants pairs have been recruited from 8 hospitals in Madrid. The characteristics of the Cohort have been previously described elsewhere. All PHIV pregnant women registered in the Madrid Cohort who gave birth from 2000 to 2015 were included in the study. Data from PHIV pregnant women since the first visit for pregnancy monitoring until delivery, and data from their infants at birth and during a follow-up period up to 24 months of age were analyzed. Infants were considered HIV-uninfected if they had at least two negative HIV-1 RNA tests, one of them after the age of 3 months. These results were confirmed with at least one HIV-1 antibody assay at the age of 12 to 18 months.Additionally, the characteristics of PHIV women before pregnancy were requested and obtained from two observational Cohorts: the Madrid Cohort of HIV-infected children and the Spanish Cohort of HIV-infected children and adolescents (CoRISPE). ,15Women were considered to have acquired the HIV infection perinatally if they were diagnosed during childhood in the absence of other risk factors and if their own mothers had been also considered as HIV-infected.Antiretroviral triple class resistance (TC-DRM) was defined as the extensive drug resistance to the three main antiretroviral families for HIV treatment, where the presence of genotypic resistance mutations was observed for at least one drug from each antiretroviral class [nucleos(t)ide reverse transcriptase inhibitors (NRTIs) non-nucleoside reverse transcriptase inhibitors (NNRTIs) and boosted protease inhibitors (PIs)].High risk factors for HIV mother-to-child transmission were defined as one or more of the following: (1) a plasma HIV-1 RNA  higher than 200 copies/mL in two consecutive samples after week 28 of pregnancy (VF after 28 weeks), (2) or any detectable viral load close to delivery, (3) or harbouring TC-DRM. Newborns were considered small for gestational age (SGA) when birth weight was lower than <10th percentile based on Spanish gender-specific standards.  CongenitThe study was approved by the Institutional Review Board at Hospital Universitario de Getafe, Madrid, Spain.Twenty-eight pregnancies were recorded among twenty-two perinatally-infected women, corresponding to twenty-two first pregnancies and six second pregnancies; all singleton. An integrated management of the pregnant women by the Infectious Diseases, Obstetrics and Paediatrics Department was carried out in all but one case. PHIV women were assisted by psychologist during their visits to the Clinics. The maternal characteristics at conception are described in 3.Nine women (32.1%) were not on ART at the time of conception but it was initiated during pregnancy in eight of these cases. Three of these women had a CD4 count below 200 cells/mmThe mode of delivery and the pregnancy outcomes are shown in There were 9 cases of high risk for HIV mother-to-child transmission, TC-DRM were documented in three women. In all TC-DRM cases a salvage regimen led to undetectable viral load close to delivery. The characteristics of these cases are summarized in Four out of six PHIV pregnant women under virological failure after 28 weeks of gestation were not on ART before conception. Although these pregnancies were recognized early, HIV viral load was not fully suppressed at week 28 in all cases. There was a patient who rejected antiretroviral treatment and psychosocial support. Among the other patients, viral load was closely monitored and treatment options were discussed. In four of them a new antiretroviral drug was added including raltegravir. Finally, two of them achieved undetectable viral load close to delivery. Overall, maternal viral load was detectable close to delivery in four women (14.3%). In these four cases, elective cesarean section was the mode of delivery and infants received a combination of three drugs as postnatal prophylaxis.Our study showed that the situation of PHIV women in Madrid who became pregnant was challenging. They were very young at the time of first conception, with treatment adherence problems as previously described for this population, and also heavily ART-exposed. A high percentage of these women had detectable HIV-1 viral load at conception, and one third of them were on a high risk situation for HIV-1 transmission to their newborns. However, reassuringly, most of the women achieved an undetectable HIV-1 viral load close to delivery and there were not cases of HIV-1 transmission to the second generation. Another observation of our study was the high proportion of SGA newborns in our cohort, even though only one child was born prematurely.An increasing number of PHIV young people are reaching adulthood throughout Europe.  HIV-infeIt is common that perinatally HIV-infected youth started to be sexually active while still under the care of paediatric health services. ,23 When Nine women (33.4%) were not on ART at conception. Previous reports have showed that it is not uncommon that PHIV women were not receiving ART at conception. An analysis of 44 PHIV pregnant women from the United Kingdom and Ireland showed that only 71% of pregnant women were on ART before gestation.  PsychosoHigh risk situations of HIV-1 transmission, defined as TC-DRM, virological failure after week 28 of pregnancy and detectable HIV-1 viral load close to delivery, were also common. For these situations, an individual approach in the selection of ART regimens in combination with psychosocial support could be useful. The use of new antiretroviral drugs as salvage therapies based on the results of the genotypic resistance tests in women with TC-DRM should be considered. Integrase inhibitors may play an important role in achieving a more rapid decline in plasma viral load to undetectable levels. However, there were four cases of pregnant women with non-suppressed HIV viral load close to delivery. Strategies to optimize adherence, including the consideration of the women preferences, are crucial and may be challenging in high risk situations. Elective Caesarean section and combined neonatal prophylaxis could also be very important measures to avoid HIV-1 transmission. Special attention has been focused on models that integrate obstetrics and mental health services into the HIV care setting for meeting the needs of PHIV pregnant women.  This serIn previous studies there were not important gender disparities in HIV-exposed infants, ,4 althouPrematurity and fetal growth restrictions leading to low birth weight have been associated with an overall increase of neonatal and long-term morbidity and mortality in neonates. ,34 The rThere are several limitations to our study. The number of pregnancies reported makes our findings entirely descriptive. In this study we were unable to address whether the pregnancies were planned or not, and how this could affect the outcomes. We have neither analyzed the rate or causes of previous miscarriages or stillbirths. The use of illicit drugs or tobacco during pregnancy was not assessed. We did not either specifically assess obstetric complications such as gestational diabetes or comorbidities such as sexually transmitted infections.In summary, this study provides a large series of pregnancies in PHIV women, reflecting some challenges and programmatic implications of this unique population for health-care providers. The characteristics and outcomes of these PHIV women attended according to a youth-centered care model were described. Additionally to this model, specific strategies should be addressed in future or collaborative studies in order to improve the management of high-risk patients for HIV-1 transmission and thus minimize the vertical transmission rate.S1 Table(DOCX)Click here for additional data file.


Acute pain frequently transitions to chronic pain after major lower extremity trauma (ET). Several modifiable psychological risk and protective factors have been found to contribute to, or prevent, chronic pain development. Some empirical evidence has shown that interventions, including cognitive and behavioral strategies that promote pain self-management, could prevent chronic pain. However, the efficacy of such interventions has never been demonstrated in ET patients. We have designed a self-management intervention to prevent acute to chronic pain transition after major lower extremity trauma (iPACT-E-Trauma).This pilot randomized controlled trial (RCT) aims to evaluate the feasibility and research methods of the intervention, as well as the potential effects of iPACT-E-Trauma, on pain intensity and pain interference with daily activities.A 2-arm single-blind pilot RCT will be conducted. Participants will receive the iPACT-E-Trauma intervention  or an educational pamphlet (control group) combined with usual care. Data will be collected at baseline, during iPACT-E-Trauma delivery, as well as at 3 and 6 months post-injury. Primary outcomes are pain intensity and pain interference with daily living activities at 6 months post-injury. Secondary outcomes are pain self-efficacy, pain acceptance, pain catastrophizing, pain-related fear, anxiety and depression symptoms, health care service utilization, and return to work.Fifty-three patients were recruited at the time of manuscript preparation. Comprehensive data analyses will be initiated in July 2017. Study results are expected to be available in 2018.Chronic pain is an important problem after major lower ET. However, no preventive intervention has yet been successfully proven in these patients. This study will focus on developing a feasible intervention to prevent acute to chronic pain transition in the context of ET. Findings will allow for the refinement of iPACT-E-Trauma and methodological parameters in prevision of a full-scale multi-site RCT.International Standard Randomized Controlled Trial Number (ISRCTN): 91987302; http://www.controlled-trials.com/ISRCTN91987302 (Archived by WebCite at http://www.webcitation.org/6rR8G2vMs) Approximately 65% of traumatic injuries occur in individuals aged 18 to 55 years ,3, whichAcute pain is of sudden onset and is expected to last a short time, and can usually be clearly related to a specific event, injury, or illness , such asPeople with chronic pain report poorer QoL than individuals affected by common chronic diseases of the heart and lungs , making Many longitudinal studies have described chronic pain risk factors. Demographics  have been shown to play a role in the transition from acute to chronic pain in patients with major ET ,5. ModerInterventions based on a cognitive-behavioral approach have been the most frequently-studied  treatmenA recent systematic review  of psychConsidering the refractoriness of chronic pain to treatment, interest has been growing in the development of interventions intended to promote self-management behaviors before acute pain becomes chronic . Some emP=.02) at 6 months [In this regard, most randomized controlled trials (RCTs) on preventive self-management interventions have been conducted in patients with pain duration varying from 15 days to 3 months, who were treated in primary care settings or hospital outpatient clinics -35,37-436 months .Positive outcomes on work status were also demonstrated in other RCTs documenting that control group participants, receiving usual care or education through written document, were at a 3-to-9-fold greater risk of long-term sick leave  compared to those receiving the self-management intervention -39. SimiFurthermore, research findings have shown that the early implementation of self-management interventions designed to increase the patients’ abilities to respond to pain in a more adaptive way contributed to better psychological outcomes. For example, participants who received such interventions demonstrated more positive attitudes towards back pain self-care abilities and significant reductions in pain worry and kinesiophobia at 1-year follow-up ,43 compaBased on knowledge acquired from positive outcomes associated with early self-management programs, we have designed a self-management intervention to prevent acute to chronic pain transition after major lower extremity trauma (iPACT-E-Trauma). Specifically, the intervention focuses on reducing pain intensity and pain interference with daily living activities, to maintain scores <4/10, as recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) for chronic pain prevention . PatientEmpirical and clinical data have guided the development of a preliminary version of the iPACT-E-Trauma intervention, which was refined after the assessment of its acceptability by clinicians  and patients . Clinicians and patients positively evaluated the acceptability of the preliminary version of iPACT-E-Trauma. To further improve the suitability  and convenience   of the iWe aim to evaluate intervention and research method feasibility, as well as iPACT-E-Trauma preliminary effects on pain intensity and pain interference (co-primary outcomes) with daily living activities at 6 months post-injury.We aim to: (1) explore the preliminary effects of iPACT-E-Trauma intervention on patients’ perceived pain SE, pain acceptance, pain catastrophizing, pain-related fear, anxiety and depression symptoms, health care service utilization, and return to work (secondary outcomes) at 6 months post-injury; and (2) examine patients’ acceptability assessment of iPACT-E-Trauma .no pain or mild pain intensity and/or pain interference scores  [We hypothesize that the experimental group will experience a clinically significant reduction of pain intensity   and pain, <4/10)  on theseA 2-arm single-blind pilot RCT will be used. Participants will be randomized to either an experimental group  or control group  and followed according to the study time points (T1 to T8) presented in The study will be conducted in a level-1 academic trauma center in Montreal, Canada. The intervention will be provided to the experimental group during their hospitalization in the level-1 trauma center and after hospital discharge. The control group will receive an educational pamphlet while in the trauma center.The inclusion criteria will be: (1) age 18 years or older; (2) able to read and speak French; (3) have a major ET; and (4) at risk of developing chronic pain. Several chronic pain risk factors have been identified in patients with major ET, with acute pain intensity found consistently in this population. IMMPACT has recommended the consideration of this inclusion criterion in chronic pain prevention studies . PatientThe exclusion criteria among ET patients will be: (1) spinal cord injury; (2) other trauma associated with high-intensity pain  by nurses, according to standardized medical pre-printed orders, and physiotherapy sessions. To ensure that iPACT-E-Trauma effects will not be based exclusively on information and attention patients receive, an educational pamphlet will be distributed to control group participants. The pamphlet will be administered by the research nurse >24 hours (but within 7 days) after hospital admission. The research nurse will visit participants the day after educational pamphlet distribution to answer their questions. Participants will be free to seek medical or other professional care for pain management after hospital discharge.Participants in the experimental group will receive iPACT-E-Trauma as well as standard pain management interventions. These individuals will be free to seek other pain management treatments after hospital discharge. The biopsychosocial model of chronic pain and empirical data guided the development of the iPACT-E-Trauma intervention; more specifically its ultimate and immediate goals, components, activities, delivery modes, and dose .Cognitive factors refer to promoting pain SE and pain acceptance while minimizing pain catastrophizing and pain-related fear. Affective factors relate to emotional reactions, such as anxiety and depression symptoms. It is expected that the intervention’s effects on cognition and affect will influence somatic factors by supporting patients in their development of adaptive responses  to acute pain, thereby reducing the biologically-related dimension . The development of self-management behaviors and the reduction of pain intensity may then positively influence pain interference with daily living activities, health care service utilization, and return to work, which relate to the social dimension of the biopsychosocial model of chronic pain.The biopsychosocial model of chronic pain  emphasizThe ultimate goal of iPACT-E-Trauma corresponds to the primary objective of this study, which is to reduce pain intensity and pain interference with daily living activities (co-primary outcomes). Immediate goals relate to determinants that should be changed to manage acute pain and pain interference with daily living activities . To reach these goals, iPACT-E-Trauma focuses on the following components: (1) the biopsychosocial dimensions of pain and the prevention/regulation of maladaptive thoughts, emotions, and behaviors; (2) the optimal use of pharmacological strategies for acute pain management; (3) the optimal use of nonpharmacological strategies for acute pain management ; (4) the adoption of health-promotion strategies ; and (5) the return to pre-injury activities. Specific components of iPACT-E-Trauma correspond to several strategies found in cognitive-behavioral interventions . These strategies will be tailored throughout intervention sessions according to the participants’ pain experience, previous knowledge, and adherence to suggested self-management behaviors.The iPACT-E-Trauma intervention combines five individual 15-to-30-minute online, face-to-face, and telephone sessions delivered by a nurse starting 24 hours after hospital admission . The intervention also includes two face-to-face or telephone-based booster sessions lasting 15-to-20 in minutes duration. The nurse who will deliver the intervention has received training to deliver the intervention based on a cognitive-behavioral approach . PrevioAccording to the intervention dose, most preventive self-management interventions analyzed in the literature review included a total of 4 to 8 weekly sessions of 20 minutes to 2 hours in duration -39,41,43Traitement et Assistance Virtuelle Infirmière et Enseignement (TAVIE) platform [Soulage TAVIE Post-Trauma) and will be combined with a face-to-face mode of delivery during patient hospitalization. More specifically, participants will be invited to watch a virtual session, followed by a short visit by a research nurse the day after, to answer questions and reinforce learned self-management strategies. Session 2 will be given two days after session 1, and session 3 will be given one week after session 1. The two other regular sessions  will be delivered on a weekly basis face-to-face during hospitalization or patient appointment in the orthopedic outpatient clinic for medical follow-up, or by telephone if it is not possible to meet the patient in person. Two booster sessions  will be given by telephone or at the orthopedic outpatient clinic at 6 weeks and 3 months post-injury.The iPACT-E-Trauma intervention includes seven short-length sessions to facilitate their integration shortly after injury . The firplatform   adeA comprehensive set of outcome measures will be recorded 24 hours to 7 days post-injury (baseline) and 3 and 6 months later (follow-up). The Brief Pain Inventory (BPI) will measure both primary outcomes . Secondary outcomes will be quantified through validated questionnaires: the Pain Self-Efficacy Questionnaire (PSEQ), the Chronic Pain Acceptance Questionnaire-8 items (CPAQ-8), the Pain Catastrophizing Scale (PCS), the Tampa Scale for Kinesiophobia (TSK), and the Hospital Anxiety and Depression Scale (HADS). Health care service utilization will be measured via a Medical Attention Seeking and Professional Services Utilization Logbook, and return to work will be measured with a form that documents work status and responsibility modifications at work. In addition, the Patient Global Impression of Change (PGIC) scale will assess perceived improvement . All insThe BPI includes 11 items: 4 on pain intensity  measured on a 0-10 NRS , and 7 on pain interference with daily living activities, assessed on a 0-10 NRS  . The BPIPSEQ is a 10-item questionnaire, which assesses the confidence that people with ongoing pain have in their abilities to manage pain and perform activities while in pain . PSEQ scCPAQ-8 is an 8-item questionnaire measuring pain acceptance. This scale comprises two subscales: the degree to which patients engage in daily living activities regardless of pain (4 items), and the willingness to experience pain (4 items) . No infoPCS comprises 13 items divided into three subscales  measuring catastrophizing thoughts ,77. TotaTSK is a 17-item checklist developed as a measure of fear of movement/(re)injury in the context of pain . Total sHADS is a 14-item inventory divided into two subscales, each comprising 7 items to assess anxiety (HADS-A) and depression (HADS-D) . The ranPGIC ,82 is a Two questionnaires will assess intervention acceptability: (1) an E-Health Acceptability Questionnaire that integrates recommended features of Internet-based interventions  for Web The Intervention Acceptability Questionnaire is based on a validated instrument intended to describe respondents’ evaluation of intervention acceptability (Treatment Acceptability and Preference Questionnaire: TAP) . The speShort Form 12 items, Version 2The Short Form 12 items, version 2 (SF-12v2) is a 12-item general measure of health status, facilitating comparisons of outcomes among different disorders and treatments . This scAn Injury Profile Form will describe injury-related aspects that may affect patients’ pain intensity and recovery. The following aspects will be documented: mechanisms of injury, number of fracture(s), open fracture(s) and their grade, other injuries , injury severity score , type ofThe Analgesics Consumption Form will describe the analgesics taken by participants during their hospitalization in the trauma center, referring regional hospital, and/or rehabilitation center. After patients are discharged to go home, the number of pills of each analgesic taken will be documented every week. Analgesic consumption will be measured until 6 weeks post-injury, since this timeline has been associated with greater consumption of analgesics after major ET .This 10-item questionnaire documents the presence of neuropathic pain , which iPCL-5 is a 20-item self-report measure that assesses 20 Diagnostic and Statistical Manual of Mental Disorders version 5 (DSM-5) PTSD symptoms . AlthougThe sample size of a pilot trial should provide reasonable confidence to guide investigators in their decisions about proceeding to a larger trial. Sample sizes that are too large should be avoided due to costs and ethical issues. An 80% 1-sided confidence interval of estimated main trial effect size has been proposed to achieve such aims . ChronicNurses, medical residents, orthopedic surgeons, and an orthopedic trauma case manager nurse will identify possible participants, inform them about the study, and obtain their permission to be contacted by the principal investigator . These professionals have been informed about the study’s inclusion-exclusion criteria during information sessions. The name and medical file number of patients giving permission to be contacted will be provided to the PI by those who are referring participants via verbal communication or confidential voicemail messages. The PI will then visit these patients. If patients meet the inclusion criteria and wish to participate after receiving a full explanation of the study, the PI will obtain their written informed consent .The randomization sequence will be generated by a coordinating center to keep researchers blinded. A computerized random-number generator will produce the sequence. Randomization will be undertaken in permuted blocks of 4 to decrease allocation predictability. Tickets will be placed in sealed, opaque, sequentially numbered envelopes to randomize study participants to either the control or experimental group. Participants will be randomized after obtaining baseline data.The research nurse who will administer the intervention cannot be blinded to group assignment considering that she will deliver the iPACT-E-Trauma sessions. To ensure participant blinding to group assignment, the intervention will be delivered  to participants in private hospital rooms, or in hospital rooms in which no other patients are hospitalized for major ET. The research assistant (RA) who will enter data will be blinded to group assignment. A numerical code will be assigned to each participant in the two groups to allow for statistician blinding.At enrollment, the research nurse delivering the intervention will complete the Injury Profile Form and Research Methods Feasibility Form. She will distribute Sociodemographic and Outcome questionnaires to participants. Questionnaires will be placed in sealed envelopes by participants upon completion, to keep the research nurse blinded to the data. An RA will document analgesics given and services received from rehabilitation professionals before patient enrollment.During intervention delivery, the research nurse will complete the Self-Management Application Checklist to document the rate of self-management behaviors applied in relation to each intervention session. The research nurse will record information concerning intervention delivery and attrition via the Intervention Feasibility Evaluation Logbook and the Research Methods Feasibility Data Form. An RA will fill out the Daily Analgesics Consumption Form while participants are hospitalized. The medical file of participants transferred to referring regional hospitals or rehabilitation centers will be obtained to complete data on analgesic consumption. After discharge to home, an RA will contact patients’ pharmacists to inquire about analgesic distribution. Adequate use of analgesics is a self-management behavior taught within the intervention, so the research nurse will question participants assigned to the experimental group about the remaining quantity of pills in their containers at the beginning of each session, and an RA will phone participants assigned to the control group to question them at corresponding session timelines. A nurse working in the outpatient orthopedic clinic will examine patients for the presence of neuropathic pain by Douleur Neuropathique 4 at each patient’s follow-up appointments. Participants will be invited to fill out the Medical Attention Seeking and Professional Services Utilization Logbook until the conclusion of the study.Participants in the experimental group will have to complete acceptability questionnaires in the week following sessions 3, 5, and 7. Both groups will also have to complete outcome measures (the SF-12v2 and PCL-5) at 3 and 6 months post-injury. Participants will have the choice of completing questionnaires in hard copy or online . If participants select the hard copy format, acceptability questionnaires will be sent to them by mail and packages of the instruments will be provided to them at medical follow-up appointments in the outpatient orthopedic clinic. Should participants be still hospitalized in a regional hospital or rehabilitation center at the time of completing acceptability questionnaires, an RA will administer them over the phone. Instructions will be provided to participants in the experimental and control groups to return a copy of the Medical Attention Seeking and Professional Services Utilization Logbook at 3 and 6 months. If participants prefer to complete the questionnaires online, an email (including the link for questionnaire access) will be sent to them in the week preceding the 3-month and 6-month data collection points. Phone calls or email reminder(s) by an RA will follow twice, with a 1-week interval if the questionnaires are not completed on time.An RA will verify that all questionnaires have been completed at baseline and when they are returned. The RA will hold discussions with participants upon questionnaire completion soon after baseline time point measurement, and contact them by phone at data collection points, to find out why data are missing. If missing data are a result of participant inattention or not understanding a question, the RA will clarify any issues they may have and ask them to provide the missing data. Steps taken to deal with missing data will be noted in the Research Methods Feasibility Data Form.To determine the feasibility of iPACT-E-Trauma, rates of planned actions that are applied during interactions with patients, as well as the number of webpages and online documents consulted, will be obtained. Mean time spent by participants watching Web sessions and mean time required for the delivery of intervention sessions by nurses will be computed. Rates of participants’ engagement in intervention sessions and in recommended activities, as well as applied recommended self-management behaviors, will also be calculated. Descriptive data pertaining to intervention delivery challenges will be grouped into categories. Frequencies will be calculated for each category.Regarding Research Methods Feasibility, descriptive data will be obtained to document: (1) the number of eligible patients and number of participants included; (2) the frequency of recruitment approaches; (3) the mean time required to screen participants relative to their recruitment, consent, and baseline data collection; (4) the percentage of patients who accept to be randomized to either the experimental or control group; (5) the dropout rate relative to each intervention session and outcome measure time points; and (6) the attrition rate at study end . DescripAll outcome data will be analyzed via an intent-to-treat approach . To estimate differences in primary and secondary variables between the intervention and control groups, a 2-group mixed linear model design with repeated measures on 1 factor (time) will be applied. This model will allow for the detection of significant group differences in continuous outcomes over time due to the intervention. Moreover, the model incorporates the full-information maximum likelihood (FIML) procedure for handling missing data commonly occurring in repeated-measures designs. FIML allows parameter estimation and measures standard errors of parameter estimates, which are statistically nonbiased processes ,98. DiffDescriptive analyses of acceptability questionnaire data will be conducted. Frequencies will be calculated for each acceptability attribute. Answers to open-ended questions about required modifications to render the intervention more acceptable in terms of effectiveness, appropriateness, suitability and convenience will be grouped into categories for each session.Procedures have been implemented to ensure that the information participants provide in this study will be kept confidential. All participants will be assigned a unique code number. Consent forms will be stored separately from the data. A master list matching the names of participants with their study identification numbers will be kept in a locked filing cabinet separate from the data. No names or other identifying information will appear in any data that is generated.Study findings will be presented in comprehensive form and not linked to specific participants. All hard copies of the data will be stored in a locked filing cabinet in a locked office. Online survey software secured with enhanced login and encryption features will safeguard the electronic questionnaire format. Data from electronic questionnaires will be downloaded onto a password-protected computer hard-drive and onto a safety code-protected Universal Serial Bus key. Data will be deleted from online survey software at the conclusion of the study, but will be stored for 10 years and then destroyed, and treated as confidential waste.Protocol amendments will be communicated to the Institutional Review Board (IRB) and through additional information in the trial registration form. Finally, the intervention is not known to be associated with any adverse events. However, such events will be documented if they emerge throughout the study.Fifty-three patients were recruited at the time of manuscript preparation. Comprehensive data analyses will be initiated in July 2017. Study results are expected to be available in 2018.The aims of this pilot RCT are to evaluate the feasibility and research methods of a chronic pain preventive intervention. Testing the intervention will provide information on its preliminary efficacy while allowing more data to be gathered on its acceptability from the perspective of patients. Chronic pain has repeatedly been identified as an important health problem in patients with major ET, but no intervention has yet been proposed for them. Evidence from such interventions in other populations is scarce. Indeed, a great deal of attention has been devoted to the implementation of interventions when pain has already become chronic, but few studies have focused on its prevention. This RCT could allow for the development of an evidence-based intervention tailored to ET patients’ needs early after injury.Preliminary testing of the intervention will set the stage for a full RCT, should the results be promising. If a full RCT shows that the intervention is effective, it will provide professionals of multidisciplinary teams working in the trauma-orthopedics field with scientific guidance and a meaningful way in which to address acute to chronic pain transition. The development of self-management behaviors that decrease long-term reliance on the health care system corresponds to current trends put forward by health policies and health organization decision-makers  . A feasiParticipation burden is an important limitation of this study. Participants in both groups will be asked to complete numerous questionnaires over a long period of time and participants in the experimental group will also have to attend several intervention sessions. To minimize the risk of attrition related to participation burden, patients will be contacted several times throughout the study by phone or email to complete or remind them to complete questionnaires, which will help maximize continued participation. Participants will receive monetary compensation proportional to the number of outcome questionnaire packages completed and intervention sessions attended . The proposed initial number of participants to be recruited accounts for attrition rates commonly reported in longitudinal studies.A second limitation pertains to the potential generation of social desirability bias since participants will self-report their performance of intervention activities and self-management behaviors. To minimize this type of bias, participants will be informed that honest answers to questions are crucial for developing interventions that will correspond to ET patients’ needs, and determine if such interventions should be offered to patients with major ET in the future.The trial was ongoing at the time of the protocol submission. No comprehensive data analyses had begun at the time of this manuscript preparation.Centre Intégré Universitaire de Santé et de Services Sociaux du Nord-de-l’Île-de Montréal -Hôpital du Sacré-Cœur de Montréal (HSCM) in June 2016 (HSCM Project No. 2017-1333; IRB approval was obtained from the