The data under columns for the header “Large segment” and the header “Small segment” were mistakenly switched prior to submission. The corrected In the original article, there was a mistake in The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.This error included a statement which described the incorrect Table 3 in the Results section.In the original article, there was an error. Results, Two-Step Amplification of Full-Length Sequences of S, M, and L Segment vRNA of ANDV Using MiSeq From ANDV-Infected Vero E6 Supernatant or ANDV-Infected Vero E6 Cells, Paragraph number 5:A correction has been made to We used a 400x depth of coverage threshold to assess ANDV genome coverage (The supernatant samples which gave the highest genome coverage across all segments was the 1x PCR and 7x PCR. The samples from infected cells showed good coverage at 15x and 20x PCR cycles although this was only true for the S and M segments as the L segment provided no coverage at this depth.The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


JSMC Brain Science, 2019, 3: 21, https://www.researchgate.net/publication/333448328_On_The_Recall_Of_Errors_In_Recall. Nine different groups of advertisements were tested after various lapses of time up to 4 months. A comparison is made between the (short term) probability of repeating a previous error as a function of lag within a single test sequence and the (longer term) probability of retrieving an advertisement as a function of elapsed time. Both these empirical relationships can be characterised by reciprocal functions, but they are otherwise quite different. Extrapolation of long-term accessibility to short intervals suggests recall in the short term could be much better than it is; extrapolation of short-term accessibility to longer intervals poses the contrary problem. Even though the only relevant variable in this comparison appears to be lapse of time, there is a question whether this comparison between short and long term is truly like with like.The recall of 90 magazine advertisements, consisting of a Brand, a Picture and a Slogan, was tested by presenting one of these components as cue and asking for the other two. The advertisements were tested in groups of ten, each group requiring a sequence of 30 test trials (10 advertisements × 3 cues). Backwards analysis of the sequences of responses—that is, starting with the last trial and comparing it successively with the responses on earlier trials—identified many responses as repetitions of previous errors, replicating many of the findings in Laming, D. On the recall of errors in recallThe online version of this article (10.1007/s00426-020-01408-y) contains supplementary material, which is available to authorized users. Jones  proposedThe critical test of this hypothesis consists of cueing each stimulus by each of its components in turn Jones, , but sepLansdale and Laming  reportedab initio. Instead of asking of each response combination whether it was correct, Laming , a Picture (P) and a Slogan (S), culled from glossy magazines. It was a student project conducted during the academic year 1983/1984, with, of course, the resources available at that time.Anticipating the results, repetition of response combinations on preceding test trials again generates a pattern of data that persuasively suggests the fragmentation hypothesis, without that hypothesis representing any structures in memory. So the question put ceases to be relevant. Instead there is a comparison between the decreasing frequency of repetitions with lag within the one sequence of test trials and the similar decrease of accessibility over much longer delays, 20 min to 4 months, comparing the different product groups of advertisements.The stimuli were 90 advertisements culled from glossy magazines. Each advert consisted of a brand name (B), a picture (P) of the product and a slogan (S). They were divided into nine product groups  with ten advertisements in each group. Each product group was tested in a separate session, lest the mixing of, say, perfumes and food in the same test provided additional information which brand name, picture and slogan went together.The stimuli were presented on slides in a Kodak carousel projector at 15 s intervals. The slides were ordered such that every ninth slide came from the same product group, with the different product groups cycled in a fixed order. The presentation of the stimuli began about 7 pm on a Friday evening. The participants viewed the slides as a group and then proceeded directly to the first test. There followed supper in the laboratory, with two further tests that same evening. The participants returned the following morning  for a further test and, thereafter, different product groups were tested at intervals as set out in Table Each product group was tested with a series of 30 cues on slides, each slide showing one component from one of the stimuli. A picture cue showed the picture from the original advertisement with the brand and slogan blanked out. Brand names and slogans were typed in Times 12 pt, the brand names in capitals, and photographed against a black ground. The slides were ordered such that each stimulus was tested every 10 trials and successive slides always cued different attributes. Participants were given booklets and asked to write on each page, first the cue and then the two attributes paired with it in the stimulus.To explain the nature of the stimuli and the method of testing, participants were shown an example of a stimulus (a girl reaching for a bottle of Martell brandy with the slogan “Look no further”); a practice set of six advertisements for cars; and an explanation of how memory would be tested, with reference to an answer booklet, a display of the brand names, slogans and pictures of the six cars, and slides presenting the three cues for the advertisement for Martell brandy. Participants were then tested on the six car advertisements, using the procedure described above for the main experiment. This preliminary training preceded the presentation of the 90 advertisements for the main experiment.The participants were 30 undergraduate friends of the two students, who carried out this research project as part of their third-year course in psychology at the University of Cambridge Paveley  and onlytest trials, on which the different stimuli were cued in turn, three times each. The combination of cue and two responses on a test trial is an answer, except that it will sometimes be necessary to distinguish answers that are copies of the answer on the immediately preceding trial, answer (lag 0) or, simply, Ans0, from the rest. The individual components of an answer are the cue and (two) responses.‘Brand’, ‘Picture’ and ‘Slogan’ are attributes of the stimuli; a particular instance of an attribute will be called a component or, where appropriate, a response. Each product group was tested with a series of 30 answer . In the case that both responses, but not the cue, match some previous answer, I speak of a yoked pair . Finally, a yoked guess is a pair of responses that match some stimulus other than the correct one . The analyses that follow repeatedly compare these 10 different categories of recall.The analysis begins by examining the repetition of previous recalls. A BPS match , the analysis works backwards from trial n-1 to 11 and then through the stimulus set, looking for the best match to the cue and two responses. A previous answer or stimulus that matches all three attributes is always deemed a more probable source than a match of only two. Given two matches of three (or two), the most recent  is preferred over the more remote. So, the analysis looks first for a match to all three attributes. This may be the stimulus addressed at trial n, or a previous recall of that stimulus or it may be some other previous answer, of necessity containing an error. Answers that copy the answer on the immediately preceding trial (Ans0—an answer that might be still ‘in mind’ at the time) are distinguished from other repetitions of complete answers. An important question is whether such repetitions are merely apparent, due to chance, or whether they indicate a true recall from memory.For each test trial n, not this particular match, but any match, depends on the number of previous answers that could be matched by a suitable choice of responses. Irrespective of whether an answer is actually recalled, and provided only there is no complete recall of the stimulus, the analysis counts the number x of different previous answers containing the cue presented on trial n. That number varies from trial to trial. There is also some number of combinations of two responses  that might have been output at trial n. The probability of matching a previous answer (any previous answer) by chance is therefore x/99. The occurrence of such a match is a Bernoulli variable with variance (1 − x/99)(x/99). The sum of such variables over the totality of trials is a generalised binomial, with mean equal to the sum of the probabilities and variance to the sum of the individual variances. This is compared with the number of answers actually recalled. The calculation is explained in great detail in Lansdale and Laming  or the two attributes excluding the cue (a yoked pair).yoked guess. It was discovered in Laming  = 6.238 with 1 d.f., p = 0.013. This is to be expected given the lapse of time between presentation of the stimuli and test.For every sub-category except four the significance is beyond dispute and most of those repetitions must have been true recalls from memory. The four exceptions are recalls of BS pairs, either to one of the attributes as cue or as a yoked pair to P as cue and also BP pairs retrieved as a yoked guess from the stimulus. The evidence relating to yoked guesses is, however, weak; aggregating the data for all three categories of cue, BP and PS pairs are common, both as cued pairs and as yoked pairs, but Brand and Slogan do not cohere well; that is, the picture plays a pivotal role in the memory of these advertisements. Participants readily attach a brand or a slogan to a picture, but do not equally link brand and slogan together by themselves. In Lansdale and Laming  it was cMany repetitions are repetitions of previous repetitions. Figure n + 1 is also one of the responses on the immediately preceding trial (n), repetition of that preceding trial (Ans0) is highly probable (av. 0.835), except in the case that the preceding trial is Null . Second, the average proportion of repetitions for answers (lag > 0) is 0.244, but increases to 0.653  and, at the third test only, a2 is the accessibility of the first test. The model assumes the data to be homogenous when the frequencies are aggregated over nine different sets of stimuli, tested after very different lapses of time and with very different levels of correct recalls. The parameter estimates are: âs = 0.420 for the stimulus, â1 = 0.754 for the preceding trial and â2 = 0.345. The parameter â1 is greater than â2 because it refers to a more recent trial (lag 9 instead of lag 19) and âs is smaller, because of the lapse of time between presentation of the stimuli and test. The black squares in Fig. The open circles in Fig. To sum up: Repeated errors are often sourced from previous repetitions. The relation between source and repetition is of no apparent significance except for repetitions of the immediately preceding trial and for repeated answers. The same process applies to correct recalls, where it generates a martingale; the expected unconditional proportion of correct recalls does not change, but individual  sequences diverge.l is the source for each of these kinds of error. Recalls of previous answers and cued pairs display conventional recency, decreasing from 0.5 for the immediately preceding answer to zero at a lag of 29. This aligns the present experiment with free recall ; thereafter their probabilities decrease much as do those for answers. This replicates a similar result from Laming .The estimated probabilities for yoked pairs have been increased nine-fold for the following reason: A yoked pair can be sourced from any previous answer that does not include the present cue . An answer, on the other hand, can be sourced only from a previous trial on which the present cue was produced as a response. There are nine times as many trials that might be the source of a yoked pair as of an answer, but only the same number of opportunities for recall. Increasing the estimated probabilities of yoked pairs redresses this disparity. With this adjustment, yoked pairs show inverse recency up to lag 8 , while the 0.65 is chosen to take the curve close to the greater part of the proportions of answer repetitions.The inverse recency exhibited by yoked pairs requires explanation and poses the question how yoked pairs and erroneous answers are retrieved from memory in the first place. To summarise the argument in Laming : The negl does not contain a match to the trial cue. An answer retrieved spontaneously from that trial would tell the participant that that particular answer is wrong . Entering such a retrieval at the head of the mnemonic record would suppress a potential yoked guess (because from the head of the record the answer would be retrieved complete) and the positive recency of answers in Fig. Suppose the trial at Lag The preceding analysis found that many recalls are repetitions, in whole or in part, of previous recalls. It follows that those previous recalls, most of them, must have been recorded in memory. Some of those previous recalls consisted simply of two unrelated guesses to which the participants in Lansdale and Laming  accordedInstead, the analysis below traces each recall to its ultimate source, stimulus as well as answer, via a chain of intermediate recalls cp. Fig. . Some ofExtracting the data from those eleven participants who attended every testing session, Fig. The broken yellow curve (overlying the abscissa) is a continuation of the hyperbola in Fig. The proportions of yoked guesses all lie above the curve, but this is because nearly all those yoked guesses are no more than apparent, arising from the chance coincidence of two separate individual guesses that happen to match one of the stimuli. When yoked guesses are aggregated together Table , they arThe broken red curve in Fig. mentclass2pt{minim‘Holidays’ and ‘Food and Drink’ show a much greater proportion of completely correct recalls than do the other product groups. To say that student participants are more interested in these products does no more than describe what is observed. A more substantial reason is suggested in the discussion.Complete answers, cued pairs and yoked pairs are reproduced at highly significant frequencies. The only exception is BS pairs, either as cued or yoked pairs.When one component of an answer chances to be the cue on the next trial, the probability of repeating that answer, complete, is high (0.835), except when the former answer is Null, that is, the confluence of two independent guesses.Likewise, when the trial cue points to a previous complete recall of an answer (lag > 0), the probability of repetition is much increased, so that the probability of repetition of complete answers increases with successive repetitions, like completely correct recalls.The probability of repeating a specific trial decreases with lag in the same manner as free recalls, except that yoked pairs show a negative recency up to lag 8.The first analysis replicated many of the findings in Laming Complete Every event  to which the participant attends is separately recorded in memory, creating an ordered record of those events that have engaged the participant’s attention.The compilation of the record is automatic; while attention to a stimulus is at the participant’s disposal, the consequent entry into memory is not.The retrieval of a candidate response from memory is spontaneous; a retrieval becomes an overt response if it is compatible with the cue.All these results were reported by Laming . There iOn the basis of this model the next important question concerns the functional decrease in accessibility with lapse of time.t} either.The black dashed curve in Fig. Opportunities to study retention over 4 months are not common, but experiments testing retention up to 15 min are easy to arrange. Ricker, Vergauwe, and Cowan  have pubRecently Sadeh, Ozubko, Winocur, & Moscovitch  have arg“Demonstrating the existence of time-based decay in short-term memory and pinpointing its rate is especially hard because our cognitive system has at least two mechanisms at its disposal to fight against forgetting: attentional refreshing and articulatory rehearsal  accessed the original stimuli and thereby reflect the effect of delay. The trend of ‘total recalls’ can be modelled as a reciprocal Eq. , like thThe most important deviation from that trend is the marked increase in complete BPS recalls after 1 h (relative to 30 min—supper was served in between these two test sessions) and, even more, after 14.6 h, overnight. The improvement after 1 h is reminiscent of Shepard’s  study ofThe second improvement overnight might suggest the effect of ‘sleeping on it’  has proved a fragile phenomenon, sometimes difficult to replicate , but those different sets (product groups of advertisements) do not appear comparable. Shepard  showed hVery recently Joensen, Gaskell & Horner  have posa, b, c and d are the proportions of entries in each cell in Table a + b + c + d = 1.Joensen et al.’s initial unit of analysis was a 2 × 2 table Table  below re“If complex events fragment as a function of forgetting, such that some aspects of the memory trace are forgotten more quickly than others…, then we would expect to see a decrease in dependency over time.” .However, there is another, simpler and more informative, way to answer the question posed by Joensen et al. Assemble the responses to all three cues pointing to a given engram in a 3 × 3 matrix as in Table same engram. This is not so here, nor in Lansdale & Laming . Second, even after correcting for guessing, one must expect combinations of responses that do not fit any of the patterns in Fig. & Laming , and it It seems intuitive that the projection of the engram of a triple associate onto recall should be one of the five patterns in Fig. But this is not at all necessary. Analysis of the recalls of the advertisements showed that many were retrievals of previous recalls Fig.  and thatEvery event  to which the participant attends is separately recorded in memory, creating an ordered record of those events that have engaged the participant’s attention.This Discussion began with a simple model of what one might call the mechanics of memory:The compilation of the record is automatic; while attention to a stimulus is at the participant’s disposal, the consequent entry into memory is not.This is suggested here by the analysis of repeated errors. The total number of trials on which some previous error was repeated is 1495. Delete from the total number of test trials (5880) those on which recall was completely correct, and delete also the first test cycle through the stimuli, because an error cannot be repeated until after it has been made. This leaves 2272 trials of which 65.8% included a repetition of an error of some kind. We cannot, of course, know about those previous responses that were not repeated, but repetition of previous errors in recall is common.The retrieval of a candidate response from memory is spontaneous; a retrieval becomes an overt response if it is compatible with the cue; that is, a cue functions only in retrospect to select an appropriate response after it has been retrieved.This may seem counter-intuitive. I draw this distinction: Fixing attention on particular stimulus material  may require a great deal of conscious effort or  may not. But attention then guarantees entry into memory; entry into memory is a pragmatic definition of attention. It enables all sorts of everyday events to be recorded without any specific intention to retain. Some of the response combinations repeated in Fig. Yoked pairs in Table In free recall, after a first flush of recalls accessed by continuing the process of rehearsal Laming, , 2008, rThe analysis of repeated errors affords a more primitive insight into the mechanics of memory than other presently existing procedures. The serial position curve of free recall Murdock, . RepetitThe relation between accessibility and lapse of time, however, presents an unsolved problem. The analysis of repeated errors provides data Fig.  on the dThere have been very many studies of retention over short periods of time and a proportionate number of models, so much so that it has become common to speak of ‘short-term memory’ or ‘working memory’ as though these topics had no connection with retention over the longer term. But there is, to my knowledge, no experimental evidence to show that there are two distinct processes. The disconnect proceeds from the ready availability of participants for studies over a short term compared with the difficulty of testing memory over much longer intervals , but extrapolation of Eq. 2 to short delays would give an enhanced recall, greatly enhanced over that represented by Eq. Supplementary file1 (DOCX 19 kb)Supplementary file2 (XLS 42 kb)Below is the link to the electronic supplementary material.


In this work, a sensor in microstrip technology and a methodology for measuring the real part and the imaginary part of the complex uniaxial permittivity of solid anisotropic samples are presented. The sensor is based on a pair of parallel lines coupled resonators and a cleft arranged in the coupling region which allows to hold the samples under test (SUTs). The proposed methodology relates the change in the even/odd resonance frequency with the real part of the permittivity in the vertical/horizontal direction, and the change in the Q factor of the even/odd mode with the imaginary part of the permittivity in the vertical/horizontal direction. The methodology was successfully verified with the characterization, at 2.43 GHz of anisotropic samples of printed PLA, Diclad 880, and RO4350B using the knowns materials: RT5870, PTFE and RO4003. The simplest anisotropy is that of materials with two different permittivity values: known as uniaxial anisotropy. This kind of materials have a permittivity in the horizontal direction Several works have been reported in the literature for the anisotropic characterization of SUTs. Characterization methods can be classified as resonant methods and non-resonant methods. The resonant methods allow to obtain the characterization of SUTs in discrete frequency points while the non-resonant methods allow to know the dielectric properties of the material in a wide range of frequencies.14. CPW lines are used to determine the complex uniaxial permittivity11  that correlates measurements with simulations of the experiment as realistic as possible, the latter demands tuning processes, computational resources, and processing time.Among the resonant methods are those based on coupled microstrip resonators12 and Chen et al.16 proposed methods for uniaxial anisotropic characterization based on the cavity perturbation theory using cylindrical cavity resonators. In Dankov12, 16 a cylindrical cavity resonator with the mode 12 and Chen et al.16 require four measurements of S parameters, two being for the measurement with a standard sample and two for the SUT, intervening in the cavity as in Chen et al.16 or moving the sample to different cavities as in Dankov12. Furthermore, they have limitations at low frequencies due to the dimensions of the resonant cavity. However, they have the advantage of being able to determine the real part as the imaginary part of the permittivity using only experimental results. Additionally, these methods offer high precision due to the strong concentration of electromagnetic fields within the cavity.Alternatively, DankovIn this work, a sensor, and a methodology for measuring complex uniaxial permittivity in solid samples is presented. The sensor is based on a pair of parallel line coupled resonators and a cleft arranged in the coupling region to hold the SUTs. The proposed sensor makes it possible to determine the anisotropic complex permittivity through the modes of the even and odd propagation modes. Using the even mode, it is possible to determine the permittivity of a SUT in the vertical direction, while using the odd mode it is possible to determine the permittivity in the horizontal direction of the SUT. The sensor and the proposed methodology allow the characterization of the real and imaginary part of the uniaxial permittivity, it does not require space mapping, which avoids the use of simulations in the permittivity extraction process and only needs a single measurement for the SUT and a measurement with a known standard sample. The proposed methodology was successfully verified with the characterization, at 2.43 GHz of anisotropic samples of printed PLA, Diclad 880, and RO4350B using the known isotropic material; PTFE and the knowns anisotropic materials; RT5870 and RO4003.The proposed sensor is shown in Fig. mentclass2pt{minim16 and adapted in our work for the electric field configurations at the odd and even resonance frequency of the proposed sensor.The resonant cavity disturbance method consists of introducing a small sample of material into a cavity with the intention of modifying the fields inside the cavity. For a dielectric SUT introduced in the cleft of the proposed sensor, the displacement in the resonance frequency with the  by Eqs.  and 4)33\documen17. Among the main considerations that are made is that both the electromagnetic field configuration and the stored energy do not change with the introduction of the sample into the cleft. Under this statement, it is possible to consider the parameters Ai and Bi independent of the permittivity of the sample. The parameters Ai and Bi can be determined analytically, although this task is too complicated. Experimentally determining the parameters Ai and Bi can be carried out using Eqs. (Equations  and 4)  4) are wing Eqs.  and (4) The complex relative permittivity measurement methodology of a SUT is shown in Fig. first step: consists of measuring the sensor's S parameters for the following cases: (a) without sample, (b) with a known sample, and (c) with an unknown sample or SUT.second step: consists of the extraction of the resonance frequencies and the Q factor for the even and odd modes. For this, the resonance frequencies are determined as the peak values of the transmission parameter S21 [dB]. The even mode occurs at the lowest frequency relative to the odd mode, which is the resonance that occurs at the highest frequency. The Q factor was determined using the -3 dB bandwidth for the two resonant modes.third step: consists of determining the proportionality constants ing Eqs.  and 4),,third stfourth step: consists of determining the complex uniaxial permittivity of the SUT using the proportionality constants It is worth noting that with the proposed methodology it is possible to obtain The proposed sensor was implemented on a 3D printed substrate, using the PLA material with a deposit density of 50% through the honeycomb pattern. Thin films (0.127 mm dielectric thickness) of Cuclad 217 PCB material with Measurements of the S parameters were performed with a VNA (Keysight FieldFox N9918A) under laboratory conditions at constant temperature. The sensor without sample has a measured even mode resonance of 9 for the real part of the permittivity tensor. While the imaginary part of the tensor was established equal to those reported in previous works20.In this work, we have used three different knowns materials to determine the proportionality constants  of Eqs.  and 4);;\documenmentclass2pt{minim21.The method was used to characterize anisotropic samples of printed PLA with 100% deposit density, Diclad 880, and RO4350B. Table 9 and 12 GHz18. Subsequently, we had used the known istropic sample PTFE for characterize the material Diclad 880. We had 9.Also, we have used the sensor to characterize RO4350B material by means the known RO4003 material. Obtaining: 9, in this new work the space-mapping algorithm is not required to determine the permittivity. The proposed methodology relates the change in the even/odd resonance frequency with the real part of the permittivity in the vertical/horizontal direction, and the change in the Q factor of the even/odd mode with the imaginary part of the permittivity in the vertical/horizontal direction. The characterization of different common anisotropic PCB dielectrics was carried out; Diclad 880, and RO4350B. As well as PLA 3D printed material.This work has presented a new sensor in microstrip technology that allows the characterization of the dielectric properties of materials with an anisotropic approach using a completely experimental measurement method. The sensor is based on a pair of coupled parallel line resonators and a cleft positioned in the coupling region to house the SUTs. This cleft allows to limit both the volume of the sample and the location of the sample in the sensor. Therefore, the field mode lines that penetrate the sample are purely horizontal when the odd mode occurs, and vertical with the even mode. This configuration allows the implementation of cavity perturbation techniques for the characterization of a uniaxial anisotropic SUT. Therefore, in contrast to Morales et al.9 at 2.4 GHz where only the real part of the permittivity was measured obtaining 18 it was reported at 12 GHz that 9 that Regarding the Diclad 880 material, the results reported here at 2.43 GHz are close to those measured in Morales et al.22 at 12 GHz. However, when this material is printed in 3D, anisotropy is induced in the printed material, even in the samples printed with a deposit density of 100% as measured in Morales et al.21 at 2.4 GHz, obtaining 14 it was measured at 40 GHz that 14.For its part with the PLA material, it is important to mention that this thermoplastic is isotropic before being printed as measured in Dankov21. For the part of the ground plane and the power lines and resonators, the Cuclad 217 material with a thickness of 0.127 mm was used. So, the outer layers were pressed against the printed PLA to form the sensor shown in Fig. The sensor was implemented on a 3D printed substrate using PLA material and the Flashforge Finder 3D printer with precision in the z-axis direction of 2.5 µm and a precision in the x–y plane of 11 µm. The thickness of the printed substrate was 1. 316 mm using 50% deposit density by means of honeycomb mesh, with The sensor consists of an input and an output feed network of width entclass1pt{minimaDiclad 880, RT 5870, RO4350B, RO4003 and PTFE samples were cut using the CNC laser cutting machine. For their part, the printed PLA samples were printed with 100% deposit density using the printer.The entire measurement process was carried out under controlled laboratory conditions, at constant temperature (26 °C ± 0.27), pressure (101 kPa) and relative humidity (53.95 ± 0.31). For the measurement of the S parameters, the Keysight FieldFox N9918A vector network analyzer was used, performing a complete manual calibration of two ports  before the measurements using an IFBW of 100 Hz and a resolution in frequency of 218 kHz. To avoid contamination of the samples the operator wore latex gloves during handling and subsequent placement of the samples on the sensor. Each sample was measured as shown in Fig.


Musterweiterbildungsverordnung, MWBO) in 2018, the area of each field in internal medicine was redefined and a restructuring of the training period for specialists in internal medicine and rheumatology took place [With the implementation of the revision of the model training regulations for German physicians  as well as the specific contents of the specialist training in internal medicine and rheumatology.Landesärztekammern) to allow for a longer period of specialized training in outpatient rheumatologic care.The basic training period in “internal medicine” requires acquisition of at least two specialist competences which do not belong to the specializing field. This training consists of 24 months and is complemented by 6 months of training in both an emergency department and an intensive care unit. The specialized training period in internal medicine and rheumatology also extends over 36 months, of which at least 24 months are completed in inpatient rheumatologic care as defined by the MWBO [Deutsche Gesellschaft für Rheumatologie, DGRh) on behalf of the board of the DGRh with regard to core competences in specialized training in internal medicine and rheumatology. This model curriculum focuses on advanced training competences which should be acquired within the 36 months of specialized training in internal medicine and rheumatology and does not include competences relevant to the general part of internal medicine training (basic training).Based on the MWBO of 2018, a model curriculum was developed by the Commission for Education and Training of the German Society of Rheumatology  and “action competences” (experience and skills) for the specialty of internal medicine and rheumatology [The aim of the model curriculum is to establish a guideline for trainers and trainees in rheumatology, in which the training competencies of the 36-month training period in the specialty of internal medicine and rheumatology based on the MWBO 2018 are provided in a structured and synchronized manner [The defined examination and treatment procedures listed in the MWBO 2018 serve as the basis for this model curriculum [The competences to be provided and acquired were divided into 3 years of training. These competences are minimum requirements, which should be adapted to the respective training institution, so that corresponding activities or knowledge can be learned or performed at an earlier  point in time. Of course, a more in-depth teaching of competences beyond the present model curriculum is possible and desirable and can be included accordingly in the individual specialized training plan of the training institution. The structure of the specialized training competences as demonstrated here was developed by the Commission of Education and Training and consented by the board of the DGRh and is intended to enable the acquisition of competences to be coordinated over time. In addition, variable training content is also included, which is not assigned to a training section and can be acquired according to the level of knowledge in the first to third year of training.The acquisition of competences follows the structure of the curriculum with regard to learning of leading symptoms; examination; laboratory, radiology, rheumatologic diagnostics; physical therapy; and therapeutic measures. In addition, interventions  are dedicated to the second and third year of training (for details, see Table Variable contents, which are not assigned to any further training section, are osteology, training programs, and issues of radiation safety (see Table The model curriculum reflects the minimum requirements of the MWBO. In this context, it is not to be regarded as an optimal and binding training option for every rheumatology training center in Germany, but rather provides the framework for successful training as a specialist in internal medicine and rheumatology. Adaptation of the curriculum to the respective situation of the specialized training location is possible or may be necessary at any time. This includes changes in the chronologic sequence of the competence transfer, a more in-depth training in individual aspects, and addition of further training content.For a continuous development of the curriculum, the Commission for Education and Training asks particularly for feedback from the trainers and trainees regarding the content, topics, and structure of the curriculum. Thus, the curriculum is to be seen as a “work in progress,” which is why comments or suggestions for improvement to the commission are explicitly desired.In summary, the model curriculum is intended to ensure standardized and structured training and continuing education for specialists in internal medicine and rheumatology.The model curriculum enables the standardized teaching of core competences as part of specialist training in internal medicine and rheumatology.The core competences to be acquired and the variably assignable training contents are provided in three training sections over 36 months.An adaptation of the curriculum to the requirements of the respective institutions of specialized training is reasonable or may be necessary.


The main purpose of this study is to elaborate anticorrosive coatings for the welded steel 316L, since this later is widely used in industrial field. Hence, within this work we have studied the electrochemical behaviour of different zones of the welded steel 316 in 1 M HCl media. The macrography study of the welded steel has revealed the different areas with a good contrast. We have stated three different zones, namely; melted zone (MZ), heat affected zone (HAZ) and base metal zone (BM). Impedance studies on welded steel 316L were conducted in 1 M HCl solution, coating of Epoxy/Alumina composite was applied on different zones, in order to reveal the anti-corrosion efficiency in each zone. Scanning electron microscopy (SEM) analysis was undertaken in order to check how far the used coating in such aggressive media protects the studied zones and these findings were assessed by water contact angle measurements. The choice of this coating is based on the cost and the safety. We concluded that the Epoxy/Alumina composite has a good protecting effect regarding welded steel in aggressive media. For low carbon steel, the inhibitory effect of inorganic glass composed of  in 1 M HCl shows that the optical structural analysis provides a good protection for the surface1. The experimental results show that when the forging pressure increases, the hardness of the welding interface will increase when the tensile strength decreases9. The electrochemical and microstructural behaviours of "A106—Gr.B" and 316L welded pipes with nickel based alloys were studied. In welded joints, the microstructure of the heat affected zone on the root weld leads to strong grain refinement and polygonal ferrite and pearlite formation by welding heat cycle change10.316L welded steel is very useful in industry, infrastructure transportation and container transportation. The welded steel protection is usually fulfilled through its corrosion inhibition whose efficiency is based on many options and parameters, these parameters are related to the environmental perspective and reasonable cost. In the same framework, many studies have taken place11.Also, effect of the microstructure on contact angle (CA) and corrosion of ductile Iron–Graphite composite "ferrite, pearlite and graphite" was studied. It was proven that pearlite is more susceptible to corrosion than (ferrite and graphite). A higher portion of pearlite in the microstructure can be detrimental to corrosion resistance of the materialIn this section, we prepared base metals to identify the microstructure before welding. After that, we tried to highlight the influence of thermal cycle changes on the microstructure and the mechanical properties of welded steel joints with similar filler metals. We prepared welding samples by cutting a pair of ingots with a dimension of 2 cm mentclass2pt{minim2SO4 and 95% H3PO4. Afterward, we characterize the microstructure using an optical microscope, see Fig. 3C and 90% ferrite α). For the present sample, the rate of carbon is of 0.8 wt % before the welding, which is in a good consistence with the Fe–C “binary diagram”, Fig. To eliminate the surfaces roughness, the steel ingots were polished by 300, 500, 800 and 1000 grain sizes abrasive papers. This step was followed by the electrolytic polishing, we prepared an acid solution based on 5% HThis process based on generating the heat by an electric arc-struck between the samples and the electrode, a simultaneously melt occurs between the electrode and metal (500 to 800 °C).The intensity for the flat steel welding is:η stands for the yield.The welding energy is the displacement of heat source per length unit of the weld:k is a correction coefficient connected to the geometry of the joint to be welded, Fig. ≈ 90° (k = 0.67). In the current study, the used welded energy is of 20,183.58 The equivalent energy is:mentclass2pt{minimThe Fig. To study the microstructure, the optical microscope is a basic method. For the preparation of the steel 316L, it must to avoid any structural modification due to the hardening and heating of the metal.From the base metal, Fig. In the heat affected zone, Fig. 13.The hardness of the steel 316L defines the resistance of a surface of the sample to the penetration of a harder body using a tip or ball of a durometer. There are many hardness tests to estimate or compare the forte or robustness of materials15:For this, we can use the Vickers hardness principle to measure the resistance of the different samples; according to the following relationThen 17. The elastic limit depends on the inverse of the square root of the “d” grain size associated to the Hall Petch expression:For the welded sample, we find that the hardness decreases from MZ to BM, see Fig. Thickness measurements or gravimetric method.Mechanical resistance measurements .Chemical analysis of the corroding medium, in particular by electrochemical methods of solution analysis, such as polarography and electrochemical methodsThere are numerous methods to study the corrosion, most of them use different physicochemical properties of the concerned samples. It is often important to make a qualitative assessment of the corrosion type; this requires simple visual observation. Depending on the type and the conditions of the involved corrosion. The quantitative corrosion assessment can use different methods. Let us quote:Within our study we are particularly interested to the electrochemical methods which allows us following the corrosion behaviour and coating protection effect of the three studied zones of the welded steel 316L; namely melted zone (MZ), heat affected zone (HAZ) and base metal zone (BM).The welded steel sample as working electrode;A platinum electrode as counter electrode;A saturated calomel electrode (SCE) as reference electrode.Electrochemical experiments are carried out in a thermostated, double-walled pyrex cell, coupled with a conventional assembly with three electrodes:2 is exposed to the aggressive solution, the rest is covered with resin. The electrochemical measurements are carried out with an assembly comprising a potentiostat Tacussel, Radiometer PGP 201 type, piloted by the software Voltamaster1. The intensity-potential curves or polarization curve of the metal /solution interface are obtained in potentiodynamic mode; the potential applied to the sample varies continuously from − 750 to + 750 mV vs SCE, with a scanning speed of 30 mV/min. The intensity of the current is measured between the working electrode and the counter electrode.Each of the studied zone of the welded steel is regarded as a working electrode. The latter is in the form of a disc where only an active part of 0.8 cmAccording to the polarization curves which are exhibited in Fig. 1:The results showed the decrease in Table 19. Nyquist plots of steel specimens in 1 M HCl solution in the absence and presence of coating with the optimum concentrations of alumina related to each area are shown in Fig. 21. It is clear from Fig. 23:Electrochemical impedance spectroscopy measurements were carried out in order to study the kinetics of the electrode process and the surface properties of the studied system. This method is widely used to investigate the corrosion inhibition processIn the Epoxy/Alumina coating, the increase in the concentration of alumina induces the increase in the diameter of the loops as shown in the Nyquist diagrams see Fig. , which sThe inhibition efficiency (EI%) obtained from the electrochemical impedance spectroscopy results also increases with the increase in the concentration of alumina, see Table The values obtained are consistent with those calculated using potentiodynamic polarization measurements.31.The equivalent circuit (EEC) is illustrated in Fig. In order to obtain further findings on the properties of welded steel with and without the optimal concentration of alumina in the Epoxy/Alumina coating in 1 M HCl medium, we conducted a morphological study using SEM. Figure Compared with SEM micrographs of other areas, the SEM image captured for the melted area is exposed to corrosion, shows that the surface is very etched and rough. This observation is probably the result of corrosion product formation. However, we can clearly observe that the corrosion on the entire inspection surface is not uniform.In order to examine the coated zones, analyzes of the morphology coupled with EDX spectra were performed on coatings of different zones of surfaces, see Figs. As depicted in Fig. The EDX analysis evaluates the SEM observations and indicates signals attributed to Fe and a small fraction of Cl from the solution was also detected, this means that the applied coating composition is not perfectly protecting the melted zone surface. However, by comparison with the image obtained without coating we can conclude that the surface of melted zone is almost free from corrosion in the presence of coating. This is due to the formation of a physical barrier on the surface of the melted zone. These observations show that Epoxy/2wt% Alumina coating prevents corrosion of melted zone by limiting access of the electrolyte to the surface.According to SEM images of heat affected zone in the presence of the coating as illustrated in Fig. EDX analysis of the electrode surface revealed peaks with small signals Cl suggesting that the surface is protected by the coating but due to the existence of small pores Cl of the aggressive solution could reach to the studied surface.The SEM micrograph of the coating of the base metal zone is exhibited in Fig. By comparison of the results obtained in the three studied areas , we find that the rate of dissolution varies according to the following direction:The inhibition efficiency obtained in the three studied media after 1 h of immersion also follows the same order, which is in good agreement with the results obtained through polarization and impedance. This is completely consistent with the observation results of uncoated and coated SEM images.As a recapitulative, the coatings are studied through surface topography and electrochemical techniques. The Nyquist diagrams of coatings with different weight percentages of alumina content show that the Rct value increases, thus increasing inhibition efficiency. The potentiodynamic curves show that the coating is actually a mixed type. Surface analysis by scanning electron microscope also proved the results obtained by electrochemical experiments.The wettability of the uncoated and coated surfaces was investigated via measurement of the contact angle by placing a water droplet in contact with the surface using a micrometer syringe. To measure the contact angle, a camera was used to scan the droplet profile, furthermore, to avoid the effect of weight, the drop size of the distilled water was about 3 μL.In order to check that the coating has protective effect on the studied surfaces, we measured the contact angle on the attacked surfaces, which were immersed in 1 M HCl solution without and with coatings.32. The image of droplet  and the following relation:For more precision, the angle θ was also directly measured through recorded image with high-resolution CCD camera of the liquid droplet profile sited on the samples using screen protactor version 3.2 software of Iconico Inc., New York, NY, USA.According to the curve depicted in Fig. However, for the metal base area coated with Epoxy resin/0.5wt% Alumina, the contact angle increases sharply to 60°.In the case of the heat affected zone coating, the contact angle is 45°, and the lowest value is attributed to the contact angle is on the coating melting zone (is of 26°). This may be due to the strengthening effect of the alumina content on the epoxy matrix. In fact, the surface of the steel strip was studied in 1 M HCl solution. Compared with the uncoated surface, the contact angle of the coating increased significantly. This is probably due to the good adhesion of the Epoxy/Alumina coating to the surface.c = 2γL) due to the van der Waals attractive intermolecular forces; dispersive (London), polar forces , or hydrogen bonds33 can be stronger than the force of adhesion attraction between the liquid molecules and the atoms in the solid (Wc = 2γL > WSL) and hence the liquid will minimize contact with the solid surface and form a compact liquid droplet. Hence, the wetting of the surface is unfavorable.The contact angle is the balance between adhesive and cohesive energies. The cohesive surface energy of liquid  and the cohesion energy of liquid (Wc = 2γL).This equation shows that the contact angle represents the balance competition between the adhesion energy , and consequently favoring the apparition of the hydrophobicity. This result is important because the coating becomes hydrophobic by loading it with alumina.The current work focuses on the microstructure coupling study of three areas of welded steel through several electrochemical and chemical methods to study the protective effect of Epoxy/Alumina coating on welded steel corrosion in 1 M HCl environment. The experimental results clearly show that the applied coating has excellent corrosion resistance and the concentration of embedded alumina associated with each area is accurate. The polarization curve shows that the coating acts as a mixed inhibitor while reducing the anodic and cathodic processes. In addition, SEM characterization shows that the Epoxy/Alumina coating prevents corrosion in three areas through a very protective film that hinders the formation of corrosion products. The protective film is also characterized by EDX, indicating that the coating is combined with the surface of the welded steel strip, resulting in hydrophobic behaviour.


Additive and multiplicative regression models of habituation were compared regarding the fit to looking times from a habituation experiment with infants aged between 3 and 11 months. In contrast to earlier studies, the current study considered multiple probability distributions, namely Weibull, gamma, lognormal and normal distribution. In the habituation experiment the type of contrast between the habituation and the test trial was varied , crossed with the number of habituation trials  and crossed with three age cohorts . The initial mean LT to dark stimuli (around 3.7 s) was considerably shorter than the mean LT to green and gray stimuli (around 5 s). Infants showed the strongest dishabituation to changes from dark to bright (luminance contrast) and weak-to-no dishabituation to a 90-degrees rotation of the gray stimuli (orientation contrast). The dishabituation was stronger after five and seven habituation trials, but the result was not statistically robust. The gamma distribution showed the best fit in terms of log-likelihood and mean absolute error and the best predictive performance. Furthermore, the gamma distribution showed small correlations between parameters relative to other models. The normal additive model showed an inferior fit and medium correlations between the parameters. In particular, the positive correlation between the initial looking time (LT) and the habituation rate was likely responsible for a different interpretation relative to the multiplicative models of the main effect of age on the habituation rate. Otherwise, the additive and multiplicative models provided similar statistical conclusions. The performance of the model versions without pooling and with partial pooling across participants  were compared. The latter type of models showed worse data fit but more precise predictions and reduced correlations between the parameters. The performance of model variants with auto-regressive time structures were explored but showed considerably worse fit. The performance of quadratic models that allowed non-monotonic changes in LTs were investigated as well. However, when fitted with LT data, these models did not produce non-monotonic change in LTs. The study underscores the utility of partial-pooling models in terms of providing more accurate predictions. Further, it agrees with previous research in that a multiplicative LT model is preferable. Nevertheless, the current results suggest that the impact of the choice of an additive model on the statistical inference is less dramatic then previously assumed. The duration of the trial is either fixed or infant-controlled. After a repeated presentation of the habituation stimulus a new stimulus (test stimulus) is presented either after a fixed number of trials or once infant’s looking times (LTs) satisfy certain criterion . The idea behind such an experimental design is to make the habituation state of each infant similar so that the LTs in the subsequent test trials reflect properties of the test stimulus/condition rather than the differences in infants’ initial habituation state.As evidenced by reviews , infant As surveyed by “Despite the obvious utility and importance of studying visual habituation per se, the vast proportion of its use comes as a tool for familiarizing infants with stimuli prior to a test for discrimination or recognition. A better understanding of infant visual habituation will make it a more precise tool for this use, but it is also likely to contribute greatly to our understanding of the nature of early cognitive function and to the neural processes that give rise to those functions. It is our hope that, within the context of this special issue, investigators will see the importance of habituation and devote more attention to it as a phenomenon, rather than as a technique. Clear advances toward this goal await us, particularly through the use of studies of individual differences, and connectionist and mathematical modeling.”The habituation studies concerned with mathematical modeling  mostly fThe abstract measurement theory  can be vAs evidenced by the common application of ANOVA to the analysis of LTs, their additivity is commonly assumed. At the same time, this assumption appears implausible:Duration in these types of measurements is a nonnegative quantity with a nonarbitrary zero point, and it can as much be considered to be on a ratio scale as on an interval scale. Interpreting LTs proportionally to each other makes intuitively sense: an infant who is fast in processing a stimulus may display 10%  shorter LTs than others, and a difficult event may protract looking by 40% rather than by a fixed amount of time . Thus, it is possible, or even plausible, that the factors influencing the duration of looking measured from a specific zero point are not additive but multiplicative in nature.” , p. 522 EN in the current report. This distribution assumes multiplicative LTs but its truncated normal residual is similar to the statistical tools that assume additivity and normal distribution. The inclusion of multiple multiplicative models makes it possible to distinguish the importance of the shape of the probability distribution relative to the importance of the assumption of multiplicativity/additivity. Fifth, three different types of the model’s time structure were investigated. All three models assumed that a sequence of habituation trials was followed by a sequence of test trials. A trend model included the trial index as the predictor: zi,t = αi + βit + γi |t > di|, where habituation state of the participant i on trial t, di is the number of habituation trials shown to the participant i and |∘ | is Iverson bracket which is 1 if its argument is true and 0 otherwise. αi, βi and γi . Then, zi,t is simply the expected LT of infant i on trial t. αi is the initial LT, βi describes the decrease in LT per trial and γi is the additive change in LT on a test trial. With multiplicative models, the interpretation of these parameters is different. In all multiplicative cases the LT can be written as yi,t = exp εi,t, where εi,t(σi) is the distribution-specific residual. In the current report we present the multiplicative parameters as multiplicative percent increase/decrease, i.e. 100 · (exp(z0 + zδ) − 1), where z0 is some base level and zδ is the multiplicative change.The first goal of the current study was to evaluate to what degree the inferences from the additive and from the multiplicative statistical models differ. Secondly, we compared models in terms of data fit and in terms of their predictive accuracy. In a third step, the performance of models including partial pooling  was invezi,t = αi + βi (t − δi)2 + γi |t > di|. While the LT of the trend model is a monotonous function of trial/time, with the quadratic model, the maximum LT occurs at t = δi and the LT increases prior to that time point and decreases afterwards  which constrains the additivity and makes the interpretation of such parameters difficult. Hence a shifted lognormal distribution was omitted from the current investigation.For each of the 47 experiments, partial-pooling regression model . In The With respect to the experiment design, the aim was to test the candidate habituation models across a wide range of conditions in which these models, and habituation models in general, may find application. Three types of contrast between the habituation and the test stimulus were investigated while three age cohorts  were considered. In addition, four levels of the number of habituation trials were investigated. The factors were fully crossed.test stimulus. The visual stimulus was a 3 × 3 grid of rectangles, which were varied in luminance, color, and orientation. The choice of this 3 × 3 grid of rectangles as stimulus aimed to make the findings useful to research on infants’ attention. Similar stimuli are commonly used to investigate visual search in adults . Written consent was obtained from the care taker prior to each experiment session. For 336 of the experiment sessions, the care takers agreed with data publication. The raw eye-tracking data along with the code used to run the experiment and the code to analyse the data is available from The stimulus was a 3 × 3 grid of rectangles with the size of 8.8 degrees of visual angle. Each rectangle was 2.2 × 1.3 degrees. To avoid the perception of the array as a single object, the rectangles were randomly displaced by a Gaussian noise (0.22 degrees standard deviation) in horizontal and in vertical direction. The luminance and color values assigned to the stimuli are shown in During the entire presentation, the monitor background was black. Experimental sessions that investigated the luminance contrast showed dark vertical rectangles in habituation trials and bright vertical rectangles in test trials. Experimental sessions that investigated the color contrast showed green vertical rectangles in the habituation trials and red vertical rectangles in the test trials. Experimental sessions that investigated the orientation contrast showed gray vertical rectangles in the habituation trials and gray horizontal rectangles in the test trials.At the start of each trial the stimulus was shown and a sound was played by the monitor (3 s length) in order to orient the infant’s gaze toward the screen. A termination check started after the gaze of the infant remained for 200 ms within a square area of 30 degrees centered at the stimulus. The trial terminated and the stimulus disappeared, once the gaze of the infant left the designated area for more than 1 s. The choice of a 1 s threshold was recommended by The presentation was run on an Asus MG279 display which subtended an area of 59.6 × 33.9 degrees. The stimuli were presented in the lower center part of the display (7 degrees from screen center) which had been determined to provide the best color homogeneity. A rectangular frame of width 7 degrees covered with black cloth covered the monitor edges. A lamp was placed behind the screen which produced an ambient light with a day-light bulb.The presentation was controlled with Python 2.7.11 and Psychopy 1.85.2. Recording of point-of-gaze data was performed with SMI REDn Scientific at 60 Hz run with iViewX 4.4.0 software in the Smart binocular mode.LTs from experiment sessions in which infants viewed less than three test trials were excluded from the analyses which reduced the number of experiment sessions from 359 to 301 (16.1% exclusion rate). The final sample numbers by condition are shown in z is the parameter of interest and σ is the nuisance parameter. y) was sampled from the distribution on the right. EN distribution was given by Five probability distributions were investigated 2 + γi |t > di|. This model formulation departs from the model presented by δ is common to all infants. This change was necessary as an attempt to introduce an infant-specific parameter δi resulted in the failure of the statistical software to converge across all model versions. Apart from δ, the meaning of variables is the same as with the trend model.  The autoregressive model was given by ui,t = ri,t−1 + βi + γi |t − 1 = di| for t>1 and ui,1 = αi, where ri,t−1 = yi,t−1 for normal distribution and ri,t−1 = log yi,t−1 otherwise.Three classes of models were investigated that differed in how they accounted for the temporal structure: the trend model was given by The previous paragraphs described the no-pooling model. Sections from “Partial pooling: main effects” to “Parameter correlation” report results from the following partial-pooling model:bi ∈ {luminance,color,orientation} indicates the type of stimulus contrast shown to participant i, ci ∈ {4,7,10} indicates the age cohort of participant i and di ∈ {1,3,5,7} is the number of habituation trials shown to participant i. The partial-pooling model’s formula for yi,t is identical to that of the no-pooling model.where Finally, “The Effect of the Number of Habituation Trials on the Dishabituation Parameter of the Trend Model” reports results from the model that is identical to the partial-pooling model except thatThe parameter estimation was performed with PySTAN 2.19  using itF-tests from an omnibus ANOVA that was applied to the parameters obtained by fitting a no-pooling model of each distribution to the LTs of each participant. ANOVA included only the factors with theoretically plausible effects, which are listed in the table. For example, it was assumed that the number of habituation trials did not affect the initial habituation state, since the condition assignment was random. All models across all parameters showed non-significant interactions. With the exception of the autoregressive gamma model, the offset (α) significantly differed between the stimulus categories (S). With the exception of the autoregressive and the trend gamma model and the normal trend model, the offset (α) significantly differed between the age cohorts (A). The main effects of factors S and A on the slope parameter (β) were not significant. As the sole exception, the Weibull autoregressive model showed a significant main effect of age cohort on the slope parameter. The dishabituation (γ) did not significantly differ between age cohorts (A) and between the groups with different number of habituation trials . The lognormal, gamma and Weibull trend model and the lognormal autoregressive model showed a significant main effect of stimulus category (S) on dishabituation (γ).In the next step, the partial-pooling models with population-level parameters accounting for the main effects from The estimates of the main effects obtained with the other model types are provided in the supplement. The main effects obtained with the no-pooling trend models were overall similar to those of the partial-pooling trend models. As an exception, the two above-noted distribution-specific discrepancies were not observed with no-pooling models. As another exception, the dishabituation after the seventh habituation trial was similar to that after one and three habituation trials. In contrast, with the partial-pooling models, the dishabituation was elevated after five and seven habituation trials.Next, the main effects of the partial-pooling trend model and the no-pooling autoregressive model were compared. The estimates of the offset parameter were similar. Considerable differences in main effects were observed with the slope and the dishabituation parameter, both in terms of rank order and in terms of overall magnitude. Notably, the Weibull and the gamma autoregressive model suggested that dishabituation is largest after just one habituation trial. The lognormal autoregressive model was the only exception that showed main-effects estimates somewhat similar to its trend-model counter-part.The estimates of main effects of age cohort and stimulus type on the dishabituation parameter were similar for the quadratic and the trend version of the partial-pooling models and the estimates of the main effect of the number of habituation trials on the dishabituation and the estimates of the main effects on the offset were roughly similar. The main effects on the slope parameter of the quadratic models showed the reverse image of those of the trend models.The data likelihood was measured with the median parameter estimates from the no-pooling models in “No Pooling: ANOVA” and from the partial-pooling models in “Partial Pooling: Main Effects”. The results are shown in To express the magnitude of the model error in quantity which is easier to interpret, thousand samples were generated from each model and for each sample the absolute error relative to the observed LT was computed. The mean absolute error was computed by averaging across participants and trials. The distribution of these errors for each model is shown in the To evaluate the predictive performance of the candidate models, the LT on the fifth trial was omitted (censored) during the process of parameter estimation. Median parameter estimates were then used to evaluate the likelihood of the LT on the fifth trial. The results are shown in ±0.11 at r = 0 and decreases to ±0.06 at r = 0.6. In the case of no-pooling trend models, the offset and the slope parameters and the slope and the dishabituation parameters were negatively correlated. This means that infants with long initial LTs showed a faster decrease in LTs and infants with a faster decrease showed a stronger dishabituation. This pattern was also observed with the normal and the lognormal autoregressive no-pooling model and to a lesser degree with the normal partial-pooling trend model. In contrast, the multiplicative distributions with partial-pooling as well as the ones with the trend structure showed very weak correlations between these two variable pairs. Instead, the latter showed weak to moderate negative correlations between the offset and the dishabituation parameter. This means that infants with short initial LTs showed a stronger dishabituation. Overall, the partial-pooling trend model with the gamma distribution showed the lowest degree of correlation between all parameter pairs, including the pairs with the nuisance parameter.As in γB5 + γB7 − γB1 − γB3 + γC5 + γC7 − γC1 − γC3)/4. The dishabituation during a late presentation was 21.2%  higher than during an early presentation.A visual inspection of the group averages of no-pooling models indicated that the way how the number of habituation trials affected the dishabituation, varied between the stimulus categories. To investigate this interaction in detail we added the corresponding interaction variables to the model with the main effects and we removed the effect of age cohort on the dishabituation to improve the convergence but also to simplify the interpretation of the interaction. The choice of the distribution did not alter the results and hence only results from the lognormal model are presented. overfitting  + γi |t − 1>di| + ηi,t−1 = βi + γi |t − 1 = di| + ηi,t − ηi,t−1. Since the residuals of the trend model are normal, their difference is normal as well. Similar correspondence between the trend and the autoregressive model can be demonstrated with lognormal distribution by considering the multiplicative contrast log yi,t − log yi,t−1. With Weibull and gamma distribution it’s also possible to separate the parameters from the residual , the differences in the absolute error due to the choice of the distribution were small, both in absolute terms (differences of less than 0.2 s), and relative to the variability in the mean absolute error between infants for a fixed distribution . Thus, one may argue that even though some distributions are more preferable in terms of predictive performance, these differences are not practically significant. Such conclusion nevertheless does not mean that the choice of distribution does not matter as the answer to the investigated research question may depend on the choice of the distribution, which is also the argument raised by y = z + σ·η where η is standard normal distribution. The lognormal and Weibull model can be written as log y = z + σ·η where η is standard normal in the former case and where η is exponentially distributed  in the latter case. Gamma distribution can be written as log y = z + η(σ) where η(σ) is the power-law distribution. Thus, the shape of the gamma residual including its mean and variance depends non-linearly on the nuisance parameter. If the mean nuisance parameter differs between the infant groups that define the main effects and the interactions, this would affect the shape of the main effects. We suspect this was the reason why the gamma trend model showed a different main-effect pattern on the offset parameter compared to the other distributions.Did the model choice affect the conclusions in the current study, i.e. conclusions about the presence and pattern of main effects and interactions? As already discussed, the Weibull and the gamma autoregressive model showed considerable differences in the pattern and significance of its main effects and its interactions relative to the remaining models. However, the log-likelihood and absolute error showed that these models provided a poor description of infants’ LTs. If one focuses on the class of trend models, which showed the best fit, the analyses of main effects and interactions provided similar results with only few discrepancies that were noted in the results section. These concern the offset parameter obtained with the gamma distribution and the slope parameter obtained with the normal distribution. In our opinion, the first case has to do with the already mentioned fact that with the gamma distribution the residual can’t be separated from the nuisance parameter. In particular, the normal and EN model can be written as To discuss the second discrepancy, recall that with the normal trend model, the rank order of the slope estimates of the age cohorts was inversely linearly related to the rank order of the offset estimates of the age cohorts. As shown in Similar to the magnitude of the differences between distributions, the distinction between an additive and a multiplicative model was not the most salient aspect affecting the model performance. Nevertheless, when it comes to log-likelihood of partial-pooling models, the normal additive model showed the worst performance followed by the EN model. The EN trend model can be seen as a model with a multiplicative trend but additive normal residual. Apparently both, the choice of the shape of the residual and of an additive or a multiplicative trend plays a role. Unfortunately, the no-pooling version of the EN model failed to converge which underscores the difficulty with designing hybrid probabilistic models that would combine aspects of additive and multiplicative models.r = 0.8 decreased to r = − 0.17 when the LTs were log-transformed. The authors concluded that this “outcome is consistent with the assumptions that LT distributions within studies are log-normal and the factors influencing LT differences across studies tend to be multiplicative.” Intuitively, a distribution with uncorrelated parameters provides a simpler description of the data-generating process compared to a distribution that requires an additional correlation parameter to describe the inter-dependence. Correlated parameters furthermore complicate the interpretation of the parameter values. We encountered this problem in the previous section when discussing the correlation between the offset and the slope parameter of the normal trend model. Apart from this correlation we observed a medium positive correlation between the offset and the standard deviation parameter of the normal distribution which mirrors the positive correlation found with the raw LTs by rα,σ obtained with the lognormal trend model. A negative but somewhat stronger correlation was observed in the current study.The assessment of the correlations listed in and test trials. Hence this association is possibly just another manifestation of the mechanism responsible for the association between the slope and the offset. In such a case one would also expect an association between the dishabituation and the standard deviation parameter, which was not the case. A positive association between offset and dishabituation is also missing which suggests that there were two separate groups of infants, one showing a correlation between offset and slope and another group showing a correlation between slope and dishabituation. A principal component analysis supplemented with a cluster analysis would be the appropriate tool to investigate this suggestion, but, to maintain the focus, these analyses were left to future research.Another inferential pitfall is posed by the positive association between the slope and the dishabituation magnitude observed with the normal model but also with the majority of the listed no-pooling models. The association can be explained by the stronger novelty preference of the habituated infants . Though rσ,z = 0.31. The orthogonality results for gamma distribution can be found in ψ′ is the Trigamma function. For small values of σ the correlation converges to zero and for large values it converges to one. The median value  obtained with the partial-pooling gamma trend model was σ = 2.1 which corresponds to rσ,z = 0.89. In sum, the parametrization of the gamma distribution and the parametrization of the Weibull distribution used in the current study do not assume orthogonality. The weak correlations listed in As stated in this section, the parameter orthogonality provides researcher with a simpler model which in turn facilitates interpretation of parameters. In addition, β provides the slope estimate of change due to habituation or habituation rate and γ provides an estimate of the change in LT on the test trial relative to the control condition which continued to show an additional habituation trial. This is roughly similar to the change in LT on the test trial relative to the last habituation trial, which is a quantity commonly reported in habituation studies.As indicated by the overlapping percentile intervals in In the current study older infants showed longer initial LTs which is in contrast with a decrease in mean LTs found by the majority of the habituation studies found . The stuHow age affects habituation rate depended on whether additive or multiplicative decrease was considered. Recall that in the current study longer initial LTs  were accompanied by a faster habituation and we speculated that this association was responsible for the inversion of the main effect of age on the slope relative to the main effect of age on the offset. It is worth noting that such associations across age groups also occurred in other studies .To briefly discuss the effect of the different types of habituation stimulus note that the green rectangle showed longer median initial LTs than the grey rectangle which in turn showed longer initial LTs than the dark rectangle. Also note that the rectangles were presented on a black background so that green stimulus showed a stronger color contrast than the gray stimulus and both showed a stronger luminance contrast than the dark stimulus. It is difficult to classify this finding as the literature on color and luminance preferences provides mixed findings  and  degrees of visual angle which was within the rectangular acceptance area which classified the intervals of looking at the stimulus. Thus, these two saliency sources from the eye tracker contributed toward the LTs. It should be possible to identify the looks towards the two patches with a reasonable accuracy from the available eye tracking data. The effect of the attention catcher can be investigated in a similar manner. However, the latter stimulus was acoustic and it was played only for a brief moment. Hence, it seems unlikely that this affects the looking behavior beyond a brief arousal , which wThe presented parameter estimates depend on the choice of parametrization of the respective distribution. A different result may be obtained with a different parametrization and hence, care must be taken when making general statements about the performance of some particular distribution. In particular, the literature on gamma and Weibull distribution  offers aAs explained in “Implications of Measurement Theory for the Analysis of Looking Times” and “Goals”, the goal of the current study was to compare the additive and the multiplicative models and the distributions were chosen with this goal in mind. To maintain the focus, some of the extensions discussed by The superior data fit and the superior predictive fit, as well as the low parameter correlation speak in favour of the multiplicative trend models and the gamma trend model in particular. To defend the application of additive models, and more generally, the application of statistical tools that assume linearity and additivity, one may point out that the difference in the model fit in terms of absolute errors was negligible and that there were only few discrepancies between the conclusions of the additive and the multiplicative models. Our recommendation for analyses of LTs obtained with the habituation design is to apply the linear statistical methods both to the raw LTs and to the log-transformed LTs. The contrasts commonly reported in the literature coincide with the parameters of the normal and lognormal trend model respectively. While the gamma distribution showed a better fit, the difference to the lognormal distribution was small. Furthermore, the lognormal model allows simple computation which makes it preferable as a default method. If the analyses with the raw LTs and with the log-transformed LTs provide identical results, it should be sufficient to include one set of analyses in the report, while the additional analyses can be included in a supplement. If the analyses disagree, results of both analyses should be presented and discussed. In particular, the negative correlation between the initial/total LT and the habituation rate observed with the additive but not with the multiplicative model may lead to spurious conclusions. The parallel analyses provide the reader with a fair presentation, but the parallel analyses also help researchers who are interested in the formal models of habituation by highlighting the cases in which the additive and the multiplicative models disagree. Our recommendation departs from that of As many investigators before us e.g. , we recoFinally, we hope that modeling studies will move from demonstrations of a model’s capability to mimic selected aspects of habituation to systematic explorations of the model space. We hope that the current study demonstrates the usefulness of the latter strategy.10.7717/peerj.11771/supp-1Supplemental Information 1Click here for additional data file.


These findings may open up a new path to design the high efficiency all-optical modulator because the electrons can also be driven optically.The manipulation of surface plasmon polaritons plays a pivotal role in plasmonic science and technology, however, the modulation efficiency of the traditional method suffers from the weak light-matter interaction. Herein, we propose a new method to overcome this obstacle by directly controlling the couple of photon and electron. In this paper, a hybrid graphene-dielectric- interdigital electrode structure is numerically and experimentally investigated. The plasmon is excited due to the confined carrier which is regulated by the potential wells. The frequency of plasmon can be tuned over a range of ~ 33 cm The traditional optical modulator is mainly based on electro-optic crystal, semiconductor, microring resonator, Mach–Zehnder interferometer (MZI) and photonic crystal9. For example, the group of Kevin F. MacDonald demonstrated an all-optical modulator in which the propagating surface plasmon polaritons (SPPs) was controlled by the pump light via interacting with the aluminum interface10. The group of S. Sederberg proposed an ultrafast all-optical switching in a silicon-based plasmonic nanoring resonator. The transmitted signal is controlled by the photo-generated free carriers which changes the complex refractive index of the nanoring resonator11. The group of Yanjun Bao presented a graphene device to modulate the propagation of SPPs, the source/drain electrode of this device was made of a reflective antenna pair structure whose optical resonance was tuned by the applied voltage12. However, most of them modulate the light through controlling the optical properties of the medium, and then the modulation performances depend on the characteristics of medium greatly. Thus, the modulation efficiency is relatively low suffered from the weak light-matter interaction.The optical modulator can control the polarization, frequency, amplitude and phase of light, which plays a vital role in the high-speed communication systems17. Various plasmonic optical components, including lenses, reflectors, and waveguides, have been reported, demonstrating the potential capabilities of plasmonics to shrink the photonic circuits below the diffraction limit22. However, the modulation efficiency of the traditional method suffers from the weak light-matter interaction. Fortunately, the movement of electrons can affect the behaviors of SPPs effectively, a method that can directly control the characteristics (such as the movement and density) of electrons is desired to be proposed to improve the modulation efficiency. In addition, it is difficult to modulate the concentration of electron in metal while it is feasible in some semiconductor and two-dimensional materials26. Graphene is a promising material in photonic and optoelectronic applications due to its superiority of high carrier mobility, broadband optical response and facile electrical tunability31. It is reported that highly-doped graphene can support SPPs with stronger mode confinement and lower propagation losses compared to the noble metal. Benefiting from these unique electronic characteristics, graphene has become a viable foundation for developing highly integrated plasmonic devices and has a potential application in photodetector, modulator, polarizer and biosensor34.SPPs are modes of electromagnetic waves propagating along a metal surface by the interaction of light waves and surface charges. In this mode, the light wave is localized at the interface between metal and dielectric, and there is a strong coupling between the light field and the free electrons on the metal surface, which offers a unique way to concentrate optical fields down to nanometer-sized regions−1 and the obtained maximum extinction ratio is 8% by changing the confined area and the density of carrier. . This method may pave a novel way for the high efficiency all-optical modulator because the electrons can also be driven optically. Compared with the traditional plasmon modulator, the performance of proposed modulator is independent of medium, and the couple of photon and electron is directly controlled. It will have a promising application in optical communication, integrated sensor and photonic circuits36.In this letter, we propose a graphene plasmon modulator consisting of a hybrid graphene-dielectric-interdigital electrode structure. The movement of carrier in graphene can be directly regulated in the potential wells formed by the interdigital electrode, and then the SPPs can be excited. The frequency of plasmon can be tuned over a range of ~ 33 cm37. The energy of SPPs excited by the polarized infrared (IR) light will be absorbed in the graphene layer, which may introduce a resonant dip in the transmission and can be collected by the detector. By means of applying different voltage on the interdigital electrode, the frequency of plasmon can be controlled through changing the confined area and the density of carrier.Figure ω of the graphene nano-ribbons can be expressed as follows38:0 are the reduced Planck constant, the charge of an electron and the permittivity of vacuum respectively, and Ef represents the Fermi energy. It can be obtained from Eqs. (ω varies with the width d and carrier density n (d−1/2 and n1/4). The voltage applied on the interdigital electrode can introduce a potential well to control the movement of carrier and only the carrier perpendicular to the interdigital electrode is modulated. It is like a nano-ribbons if the carrier concentrates on the center of graphene and no carrier locates on the boundary. In this condition, the confined area is similar to the width of nano-ribbons41. Thus, the Eqs. . The SEM images of the sample in the center and bondary of interdigital electrode are shown in Fig. The processes of fabricating the proposed structure mainly contains following three steps: (1) Traditional photolithography and metal lift-off techniques are used to fabricate the interdigital electrodes on the silicon substrate. The linewidth, period and thickness of interdigital electrodes are 5 μm, 12 μm and 80 nm respectively. (2) A PMMA layer (with a thickness of 100 nm) is then spin on the top of interdigital electrodes. 3) A monolayer graphene is transferred on the PMMA layer by means of wet-transfer techniques A monola2 polarizer and the light is focused on the center of interdigital electrode by a lens. The SPPs can be excited only when the incident light is polarized perpendicular to the interdigital electrode. Its energy will be absorbed in the graphene layer and introduces a resonant dip in the transmission spectrum  as the voltage increases from 3 to 9 V. It is caused by the increase of carrier density and the minimization of confined area at the same time. The transmission spectrum is smooth when the voltage is 0 V because the plasmon can not be excited in this condition. The small fluctuation appeared in the spectra is caused by the instrument and the influence on the experiment can be neglected as the amplitude of resonant dip is larger than fluctuation greatly. The amplitude of the resonant dip depends greatly on the number of carrier which could resonate with the incident light. The resonant dip is maximum at a relative low voltage which is because the carrier is confined in a narrower area when the voltage increases and thus some carrier on the boundary can not interact with the incident light. The transmission spectra of the sample with a linewidth of 5 μm and period of 14 μm are shown in Fig. We performed polarization-dependent transmission experiments on the fabricated sample using Fourier transform infrared spectroscopy (FTIR) in the mid-infrared region . The polarization of the light is controlled by a MgF−1 respectively, which demonstrates that a narrower confined area will lead to the blue shift of the frequency. The transmission spectrum versus the width at different Fermi level is also shown in Fig. To verify the influence of confined area and increased carrier density on the resonance frequency, the transmission spectrum of graphene nano-ribbon with different width and carrier density is simulated. Figure In conclusion, we propose a new type of graphene plasmon modulator by directly controlling the couple of photon and electron. The modulator is demonstrated by a hybrid graphene-dielectric-interdigital electrode structure. The confinement of the carrier can be dynamically controlled by the potential well established from interdigital electrode and the plasmon can be excited. The frequency of plasmon can also be tuned by changing the confined area and the density of carrier. The experimental results match well with the theoretical predictions and the simulations. Additionally, our proposed modulator opens up a new direction for high efficiency all-optical modulators.43.The simulation is performed using the commercial finite element method (FEM), trial version of software “COMSOL Multiphysics 5.5″. The module of electrostatic is used to obtain the surface charge distribution of the structure, and the module of radio frequency is used to verify the relationship between resonance frequency and changes in carrier. The surface conductivity model and the transitional boundary condition are used in the model of graphene, and the details are discussed in the referencesThe interdigital electrode is fabricated using the photolithography and metal lift-off techniques on a silicon substrate with a size of 5 × 8 × 0.52 mm. The number of the electrode is 200, and the adhesion layer of chrome is 30 nm. The thickness of the gold electrode is 100 nm. The PMMA is span on the fabricated electrode with a thickness about 100 nm. The graphene layer is grown by chemical vapor deposition (CVD) on a copper foil and then transferred using PMMA assisted wet-transfer techniques. Before the transfer process, a PMMA layer is spin-coated on graphene on the copper foil, and the copper foil is then etched away in a ammonium persulfate solution bath for about six hours. The PMMA-graphene film floating on the etchant is moved to distilled water several times to rinse the etchant residue and then scooped by the sample patterned with interdigital electrode. Finally, the fabricated sample is dried on the heating stage for half an hour with a temperature of 120 °C.2 polarizer and the light is focused on the center of interdigital electrode by a lens with a size about 500 × 500 μm.The measurement about the transmission is using Fourier transform infrared spectroscopy (FTIR) in the mid-infrared region . The polarization of the light is controlled by a MgFThis article does not present research with ethical considerations.