The regular detection of weld seams in large-scale special equipment is crucial for improving safety and efficiency, and this can be achieved effectively through the use of weld seam tracking and detection robots. In this study, a wall-climbing robot with integrated seam tracking and detection was designed, and the wall climbing function was realized via a permanent magnet array and a Mecanum wheel. The function of weld seam tracking and detection was realized using a DeepLabv3+ semantic segmentation model. Several optimizations were implemented to enhance the deployment of the DeepLabv3+ semantic segmentation model on embedded devices. Mobilenetv2 was used to replace the feature extraction network of the original model, and the convolutional block attention module attention mechanism was introduced into the encoder module. All traditional 3×3 convolutions were substituted with depthwise separable dilated convolutions. Subsequently, the welding path was fitted using the least squares method based on the segmentation results. The experimental results showed that the volume of the improved model was reduced by 92.9%, only being 21.8 Mb. The average precision reached 98.5%, surpassing the original model by 1.4%. The reasoning speed was accelerated to 21 frames/s, satisfying the real-time requirements of industrial detection. The detection robot successfully realizes the autonomous identification and tracking of weld seams. This study remarkably contributes to the development of automatic and intelligent weld seam detection technologies. With the rapid development of industrial technology, large-scale welding devices, such as pressure vessels and conduits, have been widely used in the energy industry. However, these devices are susceptible to weld seam damages or cracks, which, if left undetected, can escalate into serious safety hazards . Manual Welding seam tracking and detection robots can complete the task of welding seam detection of bridges, pipelines and storage tanks in minutes ,4,5, andLarge-scale welding devices often require high-altitude detection, posing technical challenges for weld seam tracking and detection robots, particularly in terms of wall-climbing functionality. Extensive research has been conducted in this area, focusing on magnetic wall-climbing robots ,11,12 anWeld seam tracking and detection robots must achieve a stable mobile platform in complex environments and possess accurate and efficient capabilities for weld seam feature and path extraction. Optical sensors and image processing algorithms are commonly utilized for this purpose . A visuaAlthough the above methods partially capture the characteristics of weld seams, the complex environment surrounding weld seams, including surface rust and corrosion, can adversely affect the accuracy and speed of traditional algorithms. With the development of deep learning, neural networks have found widespread application in object detection ,23,24. ADespite the progress made in the aforementioned studies toward achieving weld seam tracking and detection, certain issues persist. The algorithm’s recognition accuracy remains seriously affected by the complex environment of weld seam detection robots. Although the above research primarily focuses on seam tracking and detection functionality, several challenges remain, particularly regarding the complex environment’s influence on algorithmic recognition accuracy. Given that algorithms are executed on the robot’s hardware equipment, path planning algorithms should prioritize minimizing computational cost. Consequently, this study aims to address these concerns by (1) establishing comprehensive weld seam datasets through data augmentation and (2) enhancing the DeepLabv3+ semantic segmentation model to realize weld seam tracking and detection with low computational costs, minimal time delays, and high accuracy.In this study, a weld seam detection and tracking robot was developed, as shown in According to the measurement and functional requirements, a wall-climbing detection robot for seam identification and tracking is designed. The detection robot consists of four McNamham wheels, four DC motors, an adsorption module, a raspberry pie and a robot body frame. A camera is installed at the front of the robot to collect weld images in real time, an adsorption module is installed at the bottom for the robot to climb the wall, and a raspberry pie is installed at the top for the deployment and implementation of the neural network algorithm at the embedded end. Four motors are installed around the robot frame to control the four wheels of the car body, respectively, so as to control the movement speed and direction.A wheeled movement mode was chosen to ensure the safety of the wall-climbing robot during movement on the wall and prevent slipping or falling hazards. This mode offered flexibility and strong obstacle crossing capabilities. The robot can move in different directions and steer at various angles by adjusting the wheel speeds on both sides, allowing it to adapt to different weld seam surfaces.For safe crawling on vertical or angled wall surfaces, the wall-climbing robot required a stable adsorption force, necessitating the design and selection of an appropriate adsorption device. Existing wall-climbing robots employ three main adsorption methods: negative-pressure adsorption, magnet adsorption, and bionic adsorption. In this study, the permanent magnet adsorption method was adopted due to its simpler structural design and more reliable adsorption force compared to those of the other two methods.The adsorption magnet used in this study was an industrial-grade permanent magnet, specifically a rubidium magnet made of rubidium iron boron, NdFeB. The performance parameters of the magnet are shown in In the process of weld seam detection and tracking, the detection robot operates in two states: the normal climbing state and obstacle-crossing state. Obstacle crossing ability is an important performance index of the robot because it needs to cross weld seams during operation. The height of the weld seam is approximately 3–4 mm. A magnetic array structure was designed in this study to enhance the robot’s ability to cross obstacles and maintain a self-adaptive adsorption force while turning. The structure was equipped with different numbers of adsorption magnets in front of the car body, behind the car body, and on the belly of the car body. m represents the number of magnetic blocks in each wavelength; m is, the closer z are the components of the relative position in the direction of In practical applications, achieving continuous changes in the magnetizing direction of permanent magnets is not feasible. This study employed discrete permanent magnets spliced together in an approximately sinusoidal magnetizing situation. Under this configuration, the magnetic induction intensity ,The performance parameters of the weld seam-tracking robot are displayed in (1)Achieving stable operation on the steel plate wall surfaces using the Mecanum wheel in combination with the permanent magnet array;(2)Identifying and extracting weld seams through the weld seam recognition system;(3)Tracking weld seams by fitting the welding path.The weld seam recognition and tracking system of the seam-tracking and detection robot consisted of multiple components, including seam recognition, path fitting, motion control, and data transmission. As shown in The weld seam detection algorithm used in this study was the DeepLabv3+ semantic segmentation network model based on deep learning. The weld seams needed to be segmented from the background image through region segmentation to annotate the weld seam image datasets and meet the requirements of the semantic segmentation network model. A self-built dataset consisting of 776 weld seam images was used, which were obtained from three different datasets, as shown in Both offline and online data augmentation strategies are used in this study. Offline data augmentation strategies are carried out before network training, and online data augmentation strategies are carried out during data set reading after network training.In deep learning, the task of semantic segmentation is to extract and segment the semantic information of the target image. When training samples, network models are prone to overfitting when the data set size is extremely small. Therefore, an offline data augmentation strategy was performed in this study using the copy paste  method. The dataset was divided into a 7:3 proportion to obtain the original image dataset. Subsequently, the dataset was annotated by segmenting the weld seam from the background image using region segmentation. In this study, the Labelme image annotation tool was employed to annotate the weld seam images and obtain labeled sample data for the dataset, as shown in The DeepLab semantic segmentation network based on cavity convolution was proposed to address issues, such as the sharp decline in image resolution and the loss of original information caused by continuous pooling or downsampling operations in full convolutional segmentation networks. As the latest version of the DeepLab series, the DeepLabv3+ semantic segmentation network  has exhiThe fundamental principle behind the DeepLabv3+ semantic segmentation network model is to extract and fuse image features in the Encode phase, followed by feature map analysis in the Decode phase. The DeepLabv3+ network’s performance advantage lies in the ASPP module, which combines cavity convolution with feature pyramid pooling to extract and fuse multiscale image feature information.In this study, the DeepLabv3+ model was improved from two aspects. On the one hand, an attention mechanism was introduced to improve the information extraction ability of low-resolution feature maps. On the other hand, the network model was optimized to reduce its complexity, resulting in the improved network structure shown in The CBAM is a modular hybrid attention mechanism that was first proposed by Woo et al. . It calcThe channel and spatial attention modules of CBAM are responsible for filtering the extracted features, ensuring the retention of important information during the encoding stage to enhance segmentation. The channel attention mechanism focuses on learning channel-specific information that greatly influences the network, and the spatial attention mechanism captures position relationship information to improve the network’s learning ability. The network can effectively learn the characteristics of weld seam images and suppress redundant information by incorporating CBAM into the encoding module of the DeepLabv3+ model, thereby facilitating the extraction of edge features of weld seams.Since semantic segmentation needs to deal with the classification of each pixel, it requires more comprehensive feature extraction and representation learning of the input image. This requires the use of more convolution operations to extract features in the image and to abstract and represent those features layer by layer in order to classify them at each pixel. In addition, semantic segmentation typically requires processing smaller input images, so the network typically requires deeper convolutional layers to extract sufficient high-level semantic features. The goal of lightweight network design is to reduce model parameters and complexity while maintaining accuracy. The DeepLabv3+ semantic segmentation network used in this study obviously improved detection accuracy, but it had a model weight of 308 M, making it unsuitable for deployment on the hardware platform of the wall-climbing robot. In this study, the backbone network and convolution module of the network model were lightweighted.(1)Structural design of the backbone networkThe original DeepLabv3+ model employed Resnet  networks(2)Design of the convolution moduleAfter Moblienetv2 replaced the original deep backbone network, the model was successfully lightened. However, its size still did not meet the requirements of the hardware platform for embedded devices. On the basis of the improved backbone network, cavity depthwise separable convolution was introduced. All the traditional 3 × 3 convolutions were replaced with cavity depthwise separable convolutions, effectively reducing the number of parameters and computations.K. The calculation process of the standard convolution kernel, The cavity depthwise separable convolution involves separating the channel and spatial dimensions in the feature map using separable convolutions. Compared to the traditional convolution kernel, hole convolution can greatly reduce the number of network parameters. This is because the hole convolution uses zero padding arranged in intervals to replace the traditional continuous convolution operation, thus avoiding a lot of parameter calculation and storage. Because the convolution operation of hole convolution can be realized via interval filling, sparse convolution can be used to speed up the training and reasoning process of the network. This can greatly improve the computing efficiency and reduce the consumption of computing resources. Depthwise separable convolution consists of two parts: depthwise convolution and pointwise convolution. The input feature map size is set to The calculation process of the depthwise separable convolution kernel, The ratio of On the basis of the above formulas, the depthwise separable convolutions require fewer computations. The receptive field of the convolution kernel can be enlarged at the same computational cost by controlling the expansion rate, allowing for the extraction of multiscale contextual information as much as possible.After the weld seam was segmented and detected by the semantic segmentation network model, the foreground segmentation image of the weld seam was obtained. However, this image alone cannot provide sufficient information for weld seam tracking and tracing by the wall-climbing robot. Hence, further processing of the welding zone image is required. The Sobel operator edge detection algorithm is relatively simple and has high detection efficiency, which is a combination of Gaussian smoothing and differential operation. The principle of the Sobel operator edge detection algorithm is to use the discrete difference operator to calculate the gray approximation of the image brightness function. Although it is more efficient than the Canny edge detection operator in practical application, its accuracy is not as good as that of Canny detection. Weld detection requires high accuracy. In this study, the edge information of the weld seam was extracted using the Canny operator. The Canny algorithm performed denoising and smoothing of the weld seam image using an appropriate Gaussian function based on rows and columns as follows,Next, the gradient amplitude, Using the above formula, the Canny edge detection operator can be used to detect the edges of the weld seam image, thereby enriching the edge detail information of the weld seam.After obtaining the weld edge information from edge detection, the least squares method is used to regress the weld edge curve and obtain the final weld center line. This centerline is then used for path planning by the wall-climbing robot.A is the coefficient matrix; The objective function for least square cubic polynomial fitting can be expressed asTherefore, the cubic polynomial obtained through least squares can be expressed asThe experimental scene in this study involved a metal welded wall surface with a diameter of 4000 mm, a height of 2800 mm, and a thickness of 10 mm, as shown in lr) was set to 1 × 10−2, the weight loss ratio (weight_decay) was set to 1 × 10−4, the batch size (Batchsize) was set to 16, and the momentum gradient descent (momentum) was set to 0.9. In total, 500 training iterations were performed in the experiment.In this study, the model was optimized using the stochastic gradient descent method  as the optimizer. The dichotomic cross-entropy loss function (CE_Loss) served as the loss function for model training. The initial learning rate (The input image size for model training was set to 380 × 380 × 3. During training, the model weights were saved every 100 iterations, and the model was verified after each training iteration. The number of early_stop rounds was set to 100. The loss curve is displayed in As shown in Three groups of comparative experiments were conducted to verify the performance advantages of the improved algorithm in weld seam detection. The improved DeepLabv3+ algorithm in this study was compared with the mainstream segmentation detection models a U-Net  and PspnThe two other semantic segmentation network models compared in On the basis of the above data analysis, the improved model in this study significantly reduced the computational requirements and greatly improved the calculation and reasoning speed while maintaining high accuracy. It exhibited clear advantages compared to the current mainstream semantic segmentation models in terms of weld seam detection speed.Various complex scenes containing weld seams, such as inside pipelines, were selected as the experimental subjects to evaluate the performance of the welding path fitting algorithm in the weld seam tracking and detection model of this study. The original drawings of weld seams and their foreground segmentation results are displayed in However, the foreground segmentation image did not clearly show the edge details of the weld seam. The weld seam foreground segmentation image was subjected to edge detection using the Canny operator to obtain clearer edge details for weld seam tracking. The detection results are displayed in Once the contour map of the weld seam edge was obtained through edge detection, the centerlines of the weld seams were fitted to provide position information for weld seam tracking by a wall-climbing robot. In this study, the centerlines of weld seam edge contours were subjected to fitting using the least squares regression method, utilizing a quadratic polynomial for fitting. The fitting results are displayed in The path fitting process shown in Four groups of experimental improvement schemes were designed to explore the influence of the improved model in this study on the performance of DeepLabv3+. The model training parameters for all four schemes were consistent. The influence of these schemes on model performance is shown in According to The results of the ablation experiments proved that the process of the improved model in this study was reasonable. It met the requirements for seam tracking and detection while meeting the real-time requirements of embedded devices.In this study, datasets were enriched using the copy and paste data augmentation strategy. This approach improved the segmentation accuracy of the model and augmented its generalization ability and robustness but also reduced the risk of overfitting during model training. A group of comparative experiments was designed to verify the effectiveness of data augmentation. Two scenarios were compared: training the model using the original image dataset without data augmentation and training the model using the augmented datasets; the results are shown in The improved network in this study was trained using both the data set with data augmentation and the data set without data augmentation. This study focused on designing a weld seam-tracking robot that combines wall climbing capabilities with path planning using artificial intelligence technology. A welding seam-tracking detection robot was developed in this study, which consists of a permanent magnet array adsorption module, McNamun wheel and detection module. Through the uniquely designed permanent magnet adsorption module, the adsorption center of the car body can be adjusted adaptively when crossing obstacles, and the functions of climbing walls and crossing obstacles at high altitudes can be realized. This study also proposes an algorithm for seam identification and path planning based on artificial intelligence technology. Data augmentation techniques were employed to expand the dataset, enabling the trained weld segmentation model to handle a wider range of detection scenarios. The size of the Deeplabv3+ segmentation model was reduced by 92.9% after lightweight improvements, making it more suitable for embedding in hardware devices. In addition, the improved model achieved a 1.4% increase in accuracy compared to that of the original model. The application of least squares polynomials for fitting the weld segmentation results demonstrated excellent performance in accurately fitting various complex welds. The total reasoning time, from image segmentation to path fitting, was 71 ms per image, meeting the operational requirements of the weld seam tracking and detection robot. The development of this robot system has enabled intelligent detection capabilities. In future work, a broader range of weld seam types will be explored, and the application scope of the robot system will be expanded.


To examine the increasing use of health economic studies and practical implications of evaluating their quality utilizing the Quality of Health Economic Studies (QHES) instrument.We first reviewed secondary references to examine ways in which health economic analyses are used in different health care settings, the manner in which these data are appraised and evaluated, and their relevance and value in decision making. The QHES, a new instrument designed to support fast, accurate initial assessments of study quality, was then introduced and validated. A case study was performed using the QHES to score the quality of 30 cost-effectiveness studies in gastroesophageal reflux disease (GERD) published since 1985. Areas where additional research could guide efforts to identify and enhance the use of higher-quality cost-effectiveness studies were suggested.Results from the published validation study of the QHES demonstrated the validity of this new instrument. The resulting QHES scores in the case study of GERD papers ranged from 43 to 91 with a mean of 63.6 (SD=14.7). Approximately 27% of the studies rated had scores less than 50, and 27% had scores above or equal to 75. All 30 studies made conclusions and recommendations and justified them based on their study results. Most studies used appropriate cost and health outcome measures. Very few studies stated the perspective of their analysis and reasons for its selection. The majority of the studies did not perform incremental analysis.An examination of the QHES validation study and the case study in GERD suggests that there is a rationale and potential utility to use a quality scoring system for cost-effectiveness studies. The QHES may play an important role in discriminating higher-quality cost-effectiveness information to enhance decision making. The QHES can also serve as a guideline for conducting and reporting future cost-effectiveness studies, as an aid in the editorial process, and for stratification in systematic reviews. Complex decisions regarding resource allocation rarely rely solely on economic considerations but do increasingly use health economic analyses. To the extent that such analyses are used, the QHES may help ensure that higher-quality analyses receive more analytic attention and greater weight in the decision-making process.


Tui Na (Chinese massage) is a relatively simple, inexpensive, and non-invasive intervention, and has been used to treat stroke patients for many years in China. Tui Na acts on specific parts of the body which are called meridians and acupoints to achieve the role of treating diseases. Yet the underlying neural mechanism associated with Tui Na is not clear due to the lack of detection methods.Functional near-infrared spectroscopy (fNIRS) was used to explore the changes of sensorimotor cortical neural activity in patients with upper limb motor dysfunction of stroke and healthy control groups during Tui Na Hegu Point.Ten patients with unilateral upper limb motor dysfunction after stroke and eight healthy subjects received Tui Na. fNIRS was used to record the hemodynamic data in the sensorimotor cortex and the changes in blood flow were calculated based on oxygenated hemoglobin (Oxy-Hb), the task session involved repetitive Tui Na on Hegu acupoint, using a block design . The changes in neural activity in sensorimotor cortex could be inferred according to the principle of neurovascular coupling, and the number of activated channels in the bilateral hemisphere was used to calculate the lateralization index.P < 0.05). Wilcoxon tests showed a significant difference between lateralization index values for the affected arm in stroke patients and lateralization index values for the dominant upper limb in healthy controls (P < 0.05), and no significant difference between lateralization index values for the less affected arm in stroke patients and that in healthy controls (P = 0.36).1. For hemodynamic response induced by Hegu acupoint Tui Na, a dominant increase in the contralesional primary sensorimotor cortex during Hegu point Tui Na of the less affected arm in stroke patients was observed, as well as that in healthy controls, while this contralateral pattern was absent during Hegu point Tui Na of the affected arm in stroke patients. 2. Concerning the lateralization index in stroke patients, a significant difference was observed between lateralization index values for the affected arm and the less affected arm (The combination of Tui Na and fNIRS has the potential to reflect the functional status of sensorimotor neural circuits. The changes of neuroactivity in the sensorimotor cortex when Tui Na Hegu acupoint indicate that there is a certain correlation between acupoints in traditional Chinese medicine and neural circuits. Stroke is a serious threat to the safety and quality of life in the world, and the rate of disability after stroke is relatively high. Most patients have motor dysfunction, especially upper limb (UL) motor dysfunction . UL moveTui Na (Chinese massage) is a therapy that uses different manipulations to act on specific parts of the body to achieve the purpose of prevention and treatment of diseases. Skilled and appropriate manipulations can positively affect the nervous, circulatory, motor, and other systems of the body . Tui Na Studies have shown that Tui Na can improve post-stroke motor dysfunction through sensory ascending stimulation , 10, butIn this research, fNIRS was used to reflect the changes of neuroactivity in the sensorimotor cortex during Tui Na Hegu  acupoint in patients with UL motor dysfunction after stroke, and to explore the correlation between acupoints in traditional Chinese medicine and neural circuits. The Hegu point is commonly used in Tui Na therapy, located between the hand’s first and second metacarpal bones, with a relatively large corresponding position in the cerebral cortex, and was easily observed by fNIRS. Therefore, the Hegu point was chosen as a representative point for the study.A total of 18 subjects were recruited, including 10 patients with ischemic stroke and 8 healthy controls without neurological or mental illness. All the stroke patients were unilateral, ischemic, and first-onset, and all were right-handed. The clinical information of stroke patients is shown in Table During the experiment, the subjects were asked to lie on the bed and avoid unnecessary physical activities, such as blinking, frowning, and speaking. Participants were required to wear fNIRS headcap which covered the bilateral frontal and parietal regions. The headcap was adjusted to mount the optodes tightly onto the head of participants to make sure the high quality of fNIRS signal acquisition. fNIRS recording started when the signal was stable. The task session involved repetitive Tui Na on Hegu acupoint, using a block design  Fig. a. The onfNIRS equipment  was used to record the hemodynamic data. A total of 21 NIRS optrodes  formed 32 observation channels [The fNIRS data was preprocessed and analyzed using NIRS – KIT  and NIRSP < 0.05. The number of activated channels in the contralateral and ipsilateral hemisphere was used to calculate the LI, LI =  /  [For the correction of motion artifacts, the Temporal Derivative Distribution Repair (TDDR) algorithm was applied to the raw hemodynamic data . Then, alateral) .For demographic data, a group comparison of sex was carried out with a chi-square test, of age a two-tailed Wilcoxon test. For fNIRS data, comparisons between LI of stroke patients and controls were carried out with a two-tailed Wilcoxon test. Comparison between LI of affected arm Tui Na and less affected arm Tui Na among stroke patients was carried out with a one-tailed Wilcoxon test.p<0.05.To reflect the differences more intuitively between groups and between conditions (Tui Na of affected / less affected arm), the preprocessed hemodynamic data of SM1 was z-score normalized and then averaged across groups and participants. The mean value of oxy-Hb changes during the 2-s period just before trial onset was subtracted from the trial average for baseline correction. Statistical significance was set at As shown in Table Figure P < 0.05). As Fig. P < 0.05), and no significant difference between LI values for the less affected arm in stroke patients and that in healthy controls (P =0.36).Concerning the LI values in stroke patients, a significant difference was observed between LI values for the affected arm and the less affected arm P < 0.0. As Fig.The results of this study indicate that patients with UL motor dysfunction after stroke do have the injury of sensorimotor neural circuits, and the combination of Tui Na and fNIRS has the potential to reflect the dysfunction of sensorimotor neural circuits. The changes in neural activity in the sensorimotor cortex during Hegu acupoint Tui Na indicate that there is a certain correlation between acupoints in traditional Chinese medicine and neural circuits.The pattern of brain activation of the affected limb after stroke was mainly bilateral in the early stage, and gradually transferred to the ipsilesional cortex with the progress of rehabilitation . TherefoThe analysis of the effect of Tui Na on neural circuits is of great significance in the clinic. The neural circuits are the basis of the coordination of sensory, motor, and balance functions, and it is also the structure and functional unit of nerve remodeling and rehabilitation. The repair of these neural circuits after injury requires the stimulation of a variety of senses, and then reconstructing the neural network connection , 29. SimThe limitations of this study are that the sample size is relatively small, Which may affect the accuracy of the study results. This study focuses on whether a single Tui Na massage at one point can cause changes in the sensorimotor cortex. And such a short and single session of Tui Na maybe not be enough to induce clinical improvement in dysfunction. In the future, we will use a session of a massage program and other physical therapy as a controlled study to operate at multiple time points, and to evaluate the UL dysfunction before and after therapy.The combination of Tui Na and fNIRS has the potential to reflect the functional status of sensorimotor neural circuits. The changes of neuroactivity in the sensorimotor cortex when Tui Na Hegu acupoint indicate that there is a certain correlation between acupoints in traditional Chinese medicine and neural circuits.


Wood, being a natural hygroscopic material, the interaction between wood and moisture plays a crucial role in wood processing and utilization. Moisture affects the physical and mechanical properties of wood, and is also one of the main external factors that cause wood deformation and cracking. Drying shrinkage is a common phenomenon during the processing and utilization of wood induced by moisture loss. Drying stress is the main cause of wood deformation and cracking. The shrinkage differential between tangential and radial direction and moisture content gradient of wood are two reasons induced the generation of drying stresses. In this review, the existing states of moisture in wood and the interaction between water molecules and wood components were systematically summarized. The current research progress and deficiencies in three aspects including the factors resulted in deformation and cracking in wood caused by moisture loss, the correlation between wood mechanical properties and moisture, as well as the development of deformation and cracking in wood under moisture loss were discussed. This review aims to facilitate further research on the deformation and cracking of wood under moisture loss by providing valuable insights and assistance, ultimately reducing the occurrence of wood deformation and cracking. And thus, it will enhance the overall utilization of wood resources, making wood better serve human life. Wood, as one of natural macromolecular material directly derived from nature, has the characteristics of low production cost, low energy consumption, non-toxicity, and non-pollution. Compared with steel, cement, plastic, wood is also a renewable, degradable, and recyclable green material . As showDrying shrinkage of wood is one of the most representative reflection of the interaction between wood and moisture . As showDrying stresses are the internal stresses in the process of wood drying, and acting as a mutual restriction within the internal tissues of the wood. It is closely related to internal factors such as the wood component, material properties, and moisture content, as well as external environmental factors such as drying temperature and relative humidity ,13,14,15Apart from drying stresses, the mechanical properties of the wood also affects the deformation and cracking of wood and are also closely related to moisture content . GeneralIn this review, the existing states of moisture in wood and the interaction between water molecules and wood components were systematically summarized. The current research progress and deficiencies in three aspects including the factors resulted in deformation and cracking in wood caused by moisture loss, the correlation between wood mechanical properties and moisture, as well as the development of deformation and cracking in wood under moisture loss were discussed. This review aims to facilitate further research on the deformation and cracking of wood under moisture loss by providing valuable insights and assistance, ultimately reducing the occurrence of wood deformation and cracking and enhancing the overall utilization of wood resources.Water in wood can exist in three main forms: free water, bound water, and water vapor . Free waThe presence of moisture in wood and interaction of water molecules with cellulose, hemicellulose and lignin, as shown in Moreover, water molecules have an impact on the glass transition temperature (Tg) of wood through interacting with lignin. Water molecules tend to bind with lignin, lowering the Tg, making the wood more pliable. When wood dries out, these water molecules are removed, leading to an increase in Tg and in the stiffness of the wood. This is also why wood’s mechanical properties change with varying humidity. Moreover, this relationship between water content and Tg plays a crucial role in various wood processing and use scenarios such as drying, thermal modification, and mechanical deformation.Wood, as a hygroscopic material, meaning it attracts and holds water molecules from the surrounding environment, and this process is termed as adsorption. In contrast, when the environmental conditions change, or when wood is heated, the water molecules move from the wood back into the environment, which is known as desorption. During the initial phase of timber drying, which involves the transformation from a log to a stable board, predominant effects include shrinkage and collapse. The stable board’s response to changing moisture content conditions when in service may involve shrinkage or expansion. Either scenario could potentially lead to distortions such as peaking and cupping. Here, the deformation and cracking is only discussed during moisture loss of wood.Drying shrinkage is a common phenomenon during desorption, which is a distinctive trait that closely related to the moisture content below the fiber saturation point. The drying defects in wood during the drying process is primarily attributed to drying stress. If we exclude the influence of inherent growth stress in wood, drying stress mainly arises from the shrinkage anisotropy and moisture content gradients. The two factors serve as the primary drivers of wood deformation and cracking.Cryptomeria japonica) wood. The results showed that microfibril angles were the primary factor affecting tangential shrinkage, while factors such as basic density, annual ring width, and latewood percentage mainly influenced radial shrinkage [The differential shrinkage between the tangential and radial directions during the drying process is one factor contributing to wood deformation and cracking. As shown in hrinkage .Betula platyphylla) wood under shrinkage anisotropy stress using cross-section discs. Results revealed that the tangential shrinkage ratio was 1.12 to 1.54 times greater than that of radial shrinkage. Differences in shrinkage characteristics were observed between heartwood and sapwood, and the differential shrinkage ratio between the tangential and radial directions increased with decreasing moisture content [Pinus massoniana) wood using digital image correlation with VIC-3D system, which reported a tangential shrinkage ratio of 5.5% and a radial shrinkage ratio of 3.5% [Additionally, there are variations in anisotropic shrinkage stress along the pith-to-bark direction. Fu et al. investigated the shrinkage characteristics of white birch  cross-section disc is shown as follows: there is moisture content gradients both in longitudinal and tangential directions in the cross-section discs. The influence of longitudinal moisture content gradient on disc cracking behavior varied with thickness, with a more pronounced effect observed in discs thicker than 30 mm, while no evident effect was observed in discs thinner than 15 mm [Moisture content gradient stress is another factor contributing to wood deformation and cracking, is commonly observed during wood drying process. As shown in an 15 mm ,38.Different from wood cross-section discs, the movement and evaporation rate between wood surface and interior during lumber drying are differential, and thus resulting in moisture content gradients between the core and surface layers. The drying stresses generated by moisture content gradients are the primary cause of drying cracks in lumber. There has yielded relatively mature theories on the research of drying stresses during lumber drying, which can be summarized as follows: during the drying of lumber, the moisture content of the surface layer is lower that of the core layer, reaching a moisture content below the fiber saturation point and initiating shrinkage. At this stage, the moisture content in the core layer remains above the fiber saturation point, and the shrinkage of the surface layer is restrained by the core layer, leading to tensile stress in the surface layer and compressive stress in the core layer. As drying continues, the moisture content in the core layer decreases below the fiber saturation point, it also undergoes shrinkage. However, due to the plastic deformation that occurred in the surface layer under previous tensile stress, the normal shrinkage of the core layer is counteracted, resulting in tensile stress in the core layer and compressive stress in the surface layer .Pinus radiata) wood. This model was validated through CT scanning experiments, demonstrating its accurate prediction of moisture content distribution across the thickness, width, and growth ring direction of the lumber [Pinus radiata) lumber during high-temperature drying, and used various experimental methods to investigate the moisture content gradient during the wood drying process [Cryptomeria japonica) lumber. This was attributed to the greater moisture content gradient between the heartwood and sapwood regions in larger cross-sectional dimensions of the lumber [Experimental testing and simulation prediction are the main approaches used in studying moisture content gradients. Experimental testing methods include the slicing method , CT scane lumber ,49. Haqu process . Moreovee lumber .The occurrence of wood deformation and cracking requires the drying stress to exceed the ultimate tensile strength in wood tangential direction. While the drying stress remains constant, the mechanical properties of wood play a decisive role in determining the occurrence of deformation and cracking. The elastic modulus, strength and other mechanical properties of wood exhibit a close relationship between wood moisture content. Therefore, the interplay between wood mechanical properties and moisture content has an important impact on the occurrence of wood deformation and cracking.Research on the relationship between wood mechanical properties and moisture content primarily focuses on the longitudinal direction, with relatively less emphasis on the transverse direction. It is generally believed that above the fiber saturation point, moisture content has little influence on wood mechanical properties. However, below the fiber saturation point, as moisture content decreases, the elastic modulus, strength, and other mechanical properties tend to increase. The transverse tensile strength of wood (perpendicular to the grain direction) is much smaller than the longitudinal tensile strength . The cracking of wood during drying occurs when the drying stress exceeds the ultimate tensile strength of wood tangential direction. Therefore, the transverse tensile strength of wood determines its deformation and cracking of wood during moisture loss.Fagus sylvatica). They performed uniaxial tensile tests on samples with varying moisture content levels ranging from 7.8% to 16.9%. The results of the study revealed that both the tensile modulus of elasticity and tensile strength decreased as the moisture content of the European beech samples increased. Specifically, the mechanical properties experienced a decrease of approximately 2–3% for every 1% increase in moisture content [Cryptomeria japonica) wood in different moisture content conditions. They examined the wood’s properties in three principal axes under four moisture content levels: 10.3%, 12.2%, 14.6%, and 16.7%. Their findings were consistent with the previous study by Ozyhar et al. Specifically, the tensile modulus of elasticity in the tangential direction decreased from 8.1 GPa at 10.3% moisture content to 4.5 GPa at 16.7% moisture content [The study conducted by Ozyhar et al. focused on investigating the relationship between transverse mechanical properties and moisture content in European beech ( content . The stu content . In addi content .Populus sp.) and Chinese fir (Cunninghamia lanceolata) [Populus sp.) decreased by 20.3%, and that of Chinese fir (Cunninghamia lanceolata) decreased by 34.8%. In another study by Yue et al., they suggested that the transverse tensile strength and tensile modulus of elasticity of Chinese fir (Cunninghamia lanceolata) exhibited a linear decrease with increasing moisture content within the range of 7% to 20% [The study conducted by Zhan et al. examined the influence of moisture content on the transverse tensile strength of two different wood species: Poplar (ceolata) . They fo% to 20% .Cryptomeria japonica). They introduced a simplified model of wood fibers, enabling a theoretical representation of the connection between longitudinal elastic modulus and moisture content. They suggested that the impact of moisture content on the elastic modulus is attributed to the presence of a transition zone between the crystalline and amorphous regions of cellulose microfibrils. This transition zone undergoes fluctuations within this transition zone as moisture content changing, thereby influencing the mechanical properties of wood cell walls [The specific relationship between macroscopic properties of wood and moisture content is largely determined by the microstructure of wood. However, there is currently a limited amount of research available on the connection between the mechanical properties of wood cell walls and moisture content. Yamamoto et al. conducted a study on the relationship between cell wall components and the longitudinal elastic modulus in Japanese cedar  at a range of moisture content levels. The results suggested that both the elastic and viscosity constants of the wood decreased with increasing moisture content. They further proposed that increased moisture rendered the wood cell walls softer and thicker. This induced greater susceptibility to disruption in the hydrogen bonds among microfibrils, culminating in a decrement in the mechanical properties of wood [Yu et al. applied nanoindentation technology to investigate the relationship between the longitudinal mechanical properties of latewood cell walls in Masson pine sapwood and their moisture content. The results highlighted a linear relationship between the elastic modulus, hardness, and compressive yield stress of the wood cell walls, and the moisture content within the examined range. Specifically, it was observed that as the moisture content rose from 4.5% to 13.1%, there was a corresponding decrease in the elastic modulus of the wood cell walls from 20.4 GPa to 16.9 GPa. Moreover, the impact of the moisture content on the hardness was found to exceed its effect on the elastic modulus . As show of wood .Cryptomeria japonica) square timber. Their findings indicated that the ratio of heartwood and radial shrinkage primarily influence surface cracking. Specifically, the length of the cracks displayed a direct proportionality to the radial shrinkage. Moreover, internal cracking near the pith was found to be relatively severe, largely due to the impact of radial shrinkage [In the field of wood macroscopic cracking, Wahl et al. employed a method utilizing laser reflection intensity to examine surface microcracks in wood. The reflective intensity of the wood surface was used as a measure to characterize the state of the cracking . Utilizihrinkage ,65. Phonhrinkage . Larsen hrinkage .Gmelin larch) at a temperature of 60 °C, thereby facilitating the capture and tracking of the inception and expansion of microscopic cracks on the wood surface. Sakagami investigated the timing and location of microcrack formation using laser confocal microscope by placing Japanese cedar (Cryptomeria japonica) in an environmental control box at 50 °C with a Relative Humidity of 5% [Compared to macroscopic cracks, micro-cracks present greater observational challenges due to their scale during formation and expansion. Fan et al. successfully designed a microscopic image acquisition system by ingeniously integrating a microscope with a custom-made drying oven . This inty of 5% . The resty of 5% . This apQuercus rubra) and Long-fruited Oak . Results showed that wood with a high density and low porosity was more susceptible to cracking, and thick-walled cells were more prone to cracking than thin walled. Multiple initial failure points were discovered in both types of wood, a phenomenon tied to their intricate anatomical structures [Cryptomeria japonica) and the microcracks was employed by an enhanced confocal laser scanning electron microscope. The findings revealed that microcracks started to form near the fiber saturation point (28.9%), and cracks attained their maximum value as moisture content reached 9.9%, and then gradually closed with further moisture depletion. The cracks were first observed between the tracheid and the ray parenchyma cells in latewood. As the moisture content decreased, the crack propagated along the ray parenchyma cell towards both ends, and the crack tip ended at the boundary of the next growth ring [Pinus massoniana) tracheids during drying. Results showed that cracks initially manifested in the intercellular layer between the ray tissue and the tracheid, as well as between the ray cells [In a study focusing on cracking at the cellular level in wood, Wang et al. conducted an examination of the microscopic cracking patterns in two types of wood during the drying process: Red Oak (ructures . Saka etructures . The corwth ring ,74. As say cells .Drying stress, primarily induced by the anisotropy of drying shrinkage and the moisture content gradient during wood processing, is the main contributor to wood deformation and cracking under moisture loss. The drying stress is principally associated with the inherent drying shrinkage properties of the wood, the thickness of the board, and surrounding temperature and humidity conditions. The disparity between tangential and radial drying shrinkage of wood is determined by the inherent characteristics of wood. This disparity is an inevitable part of the drying process, especially in wood cross-section discs drying, which have to handle the impacts of this in processing and in applications. However, the moisture content gradient during the drying process can be modulated by controlling the surrounding temperature and humidity conditions. Mitigating the moisture content gradient in wood throughout the drying process serves as an effective strategy to minimize wood deformation and cracking. Currently, numerous studies focus on the differences of tangential and radial shrinkage and the moisture gradient during wood drying, but a quantitative depiction of the relationship between drying stresses and wood cracking. Consequently, future research must emphasize the accurate detection of drying stresses within the process of wood drying, in conjunction with quantifying the correlation between drying stress and wood deformation and cracking. Except for the drying process, MC change can also deform boards, leading to cupping and other deformation in service. In addition, there are some treatment method such as microwave technology, is a useful way to relief of growth and drying stresses in rapid drying of hardwoods ,76.Identifying the relationship between the transverse mechanical properties of wood and its moisture content is key to understanding the drying cracking during the moisture discharge process. Therefore, future studies should explore variations in tangential tensile strength in different moisture conditions and within specific areas of the wood, such as earlywood and latewood, or heartwood and sapwood. The macroscopic mechanical properties of wood are largely determined by its microscopic structure. This is primarily observed in the dynamic relationship between the degree of cellulose crystallinity in the wood and moisture, i.e., the crystalline and amorphous regions of the cellulose microfibrils are changed with variation moisture content. Current studies have extensively researched the relationship between the mechanical properties of wood cell walls and moisture, yet studies evaluating the impact of the main chemical components of wood on its mechanical properties remain scarce. Emphasizing the effect of moisture content changes on wood mechanical properties at the cell wall level and molecular level will be a pivotal aspect of future research. This focus is critical for elucidating the mechanisms of wood deformation and cracking in response to moisture loss.The transverse tensile strength of wood is crucial in determining its deformation and cracking behavior under moisture loss. Research into the mechanical properties of wood in transverse direction, particularly the tangential tensile strength, has been comparatively limited. Identifying the relationship between the transverse mechanical properties of wood and its moisture content is key to understanding the drying cracking during the moisture loss. Therefore, future studies should explore variations in tangential tensile strength in different moisture conditions and within specific areas of the wood, such as earlywood and latewood.


Bimaxillary orthognathic surgery is widely used for the correction of dentoskeletal deformities. Surgery sequencing (maxilla or mandible first) remains debated, and guidelines and consensus are lacking. This scoping review summarizes the state of the art and compares the advantages and disadvantages of both approaches. The review was conducted following PRISMA-ScR guidelines. Three electronic databases  were searched using the PICO protocol and key words in orthognathic surgical sequencing. Four reviewers screened the records independently, and disagreement was resolved by consensus. A total of 23 records met the inclusion criteria. The advantages and disadvantages of the two approaches were compared and assessed for accuracy of reporting. Within the limitations of the present study, available evidence for the intrinsic advantages and the accuracy of the mandible-first sequence supports the choice of this approach in most cases. Nevertheless, each clinical case needs to be evaluated individually, as no dogmatic recommendations can be given for sequencing in bimaxillary orthognathic surgery. Since the introduction of internal rigid fixation, it has become the surgeon’s choice to decide which jaw to operate first in bimaxillary surgery for correcting malocclusion and improving facial appearance simultaneously ,2. In thWith the introduction of titanium plates and screws, however, operating the mandible first has become a valid alternative, as it can be rigidly fixed and used as a stable reference point to reposition the maxilla. Surgeons can now easily stabilize both jaws effectively regardless of the sequence. Although the mandible-first sequence has attracted increasing interest among orthognathic surgeons, it is not known whether the mandible-first sequence is an alternative to the maxilla-first sequence out of convention or due to its real advantages.To achieve optimal outcomes, surgical protocols should be closely followed to minimize the risk of complications and improve long-term results. Deciding which sequence to choose on a case-by-case basis in bimaxillary surgery is fundamental for improving the reliability of such a technically complex surgery and for achieving predictable outcomes ,4,5.-Provide a summary of the available literature on sequencing in bimaxillary surgery;-Compare the advantages and the disadvantages of both sequences;-Provide clear indications for both sequences;-Suggest a systematic study approach to those who intend to review the recent literature on this topic.Currently, very few studies summarize or compare the advantages and disadvantages of the two sequences. An extensive review of the topic is beyond the scope of the present article. The aim was to:This scoping review was conducted according to PRISMA Extension for Scoping Reviews (PRISMA-Scr) guidelines . This stA total of 82 abstracts were retrieved from the three databases (75) and through in-text citations (7). After removal of duplicates, the remaining 42 abstracts were analyzed for relevance: consensus by all four reviewers was reached for 16; 6 were excluded, and 20 were listed as uncertain. The uncertain ones were further discussed: 7 were included in the study, and 13 were excluded. The final pool for this scoping review consisted of 23 records , which wA shift in study topics was noted over the years. While initially, there was interest in the advantages and the disadvantages of the mandible-first sequence with regard to surgical planning and surgical execution, the more recent studies investigated surgical accuracy and patient-specific implants (PSI) with both sequences. Most studies underscored the advantages of the mandible-first sequence, while few discussed the advantages of the maxilla-first sequence.The risk of bias assessment showed an overall high quality of the studies, particularly for blinding and objectiveness of the measurements and completeness of data . There wSequencing in bimaxillary orthognathic surgery has attracted intense debate, especially since the introduction of internal rigid fixation, which raised questions about the most appropriate sequence of osteotomies for correcting dentofacial deformities and achieving stable clinical results . InteresThis scoping review identified several key-points to consider before adopting the traditional or the inverted sequencing. What is beyond any doubt is that the decision about which jaw to operate on first must be taken at the time of surgical planning . The entFor example, the maxilla-first sequence is indicated in the clockwise rotation of the jaws, when a single-piece Le Fort I osteotomy is performed or when internal rigid fixation is unfeasible. This sequencing is also preferred in small maxillo-mandibular advancements or when maxillary impaction is required, which allows for the design of an intermediate splint that is thin enough to facilitate intraoperative rigid Maxillo-Mandibular Fixation (MMF) .Choosing the mandible for the first osteotomy seems to be beneficial in the following scenarios. As stated by Posnick et. al., the mandible-first sequence is required when an accurate and reliable preoperative bite registration is not possible  and whenOperating the mandible first is also advantageous in multi-segmental maxillary osteotomies in which maxillary fragments are oriented according to the mandibular arch; this provides an occlusal guide for achieving accurate and deep intercuspation, without the need for a palatal splint . Perez eAlthough the mandible-first sequence seems to be a reliable technique, it has several noticeable drawbacks. When a bad split of the mandible cannot be properly managed and the condyle cannot be passively placed in the fossae, the operation may need to be interrupted. Additionally, when a large maxillo-mandibular advancement with clockwise rotation is planned, the intermediate splint in a mandible-first sequence could create a large anterior open bite and make rigid MMF difficult to achieve; in such cases, a maxilla-first sequence is advised. An additional consideration is the extent to which the choice of a surgical sequence could influence the treatment accuracy. Some authors stated that the two sequences are equally accurate, as both adhere to virtual surgical planning with comparable precision ,19,21. ISalmen et al. reported that the conventional sequence produced better esthetic outcomes due to the better accuracy of the vertical position of the upper incisors. In contrast, the mandible-first sequence was more accurate for the Pogonion vertical position . Shah etThe development of Patient-Specific Implants (PSIs) with customized cutting guides and plates could represent a further improvement regarding this aspect. According to Badiali et al., PSIs produce clinically accurate results with both sequences . TherefoA final concern relates to the amount of mandibular autorotation required for the creation of the intermediate splint. It is postulated that the greater the amount of mouth opening, the greater the degree of inaccuracy. Recent studies, however, refute this postulate, as no correlation was found between mandibular autorotation and the inaccuracy of the final result .In conclusion, based on the indications and the contraindications for sequencing, the mandible-first sequence appears to be the better choice in most bimaxillary surgery procedures. The surgeon’s personal experience and expertise play a central role in the choice of the surgical sequence, in which each case is evaluated individually, without dogmatic recommendations on which jaw should be operated first.The present review has several limitations, including its vast and largely conceptual topic and the relatively small sample size. Prospective case-control studies are needed to establish the scientific soundness of the concepts underpinning orthognathic sequencing.


Since late 2020, SARS-CoV-2 variants have regularly emerged with competitive and phenotypic differences from previously circulating strains, sometimes with the potential to escape from immunity produced by prior exposure and infection. The Early Detection group is one of the constituent groups of the US National Institutes of Health National Institute of Allergy and Infectious Diseases SARS-CoV-2 Assessment of Viral Evolution program. The group uses bioinformatic methods to monitor the emergence, spread, and potential phenotypic properties of emerging and circulating strains to identify the most relevant variants for experimental groups within the program to phenotypically characterize. Since April 2021, the group has prioritized variants monthly. Prioritization successes include rapidly identifying most major variants of SARS-CoV-2 and providing experimental groups within the National Institutes of Health program easy access to regularly updated information on the recent evolution and epidemiology of SARS-CoV-2 that can be used to guide phenotypic investigations.  As part of the US National Institutes of Health (NIH) National Institute of Allergy and Infectious Diseases (NIAID) SARS-CoV-2 Assessment of Viral Evolution (SAVE) effort to combat the SARS-CoV-2 pandemic, the NIH NIAID SAVE Early Detection Group regularly prioritizes SARS-CoV-2 variants. The main goal of prioritization is to identify relevant lineages for phenotypic testing by experimental groups within the NIH SAVE network by integrating up-to-date epidemiologic, structural, and genetic information. Practically, this process involves regular contact with the experimental groups in weekly meetings and continued consideration of the types of experimental work the groups conduct, which includes characterization for replicative fitness, pathogenicity, and antigenic escape.The SAVE Early Detection Group does not attempt to recapitulate the efforts of numerous public health organizations worldwide to designate variants of concern and variants of interest . Four types of rank can be assigned .Ranks are first transformed to numeric ranks . LineageLineages that come to the group’s attention in between prioritizations can be added outside of the normal monthly timeline. They are added to a rank determined directly by discussion between the subgroups.Ranking methods are presented in general terms because ranking is often performed by hand rather than algorithmically. Manual ranking is performed because of the need to weigh numerous factors, including which types of variation are most interesting to characterize at any particular time.The 9 Teamshttps://cov.lanl.gov) (https://www.gisaid.org). Because spike protein variants are often found in multiple Pango lineages  team, led by author B.K., developed tools for early detection of spike variants (https://coronavirus3d.org). For the final variant and subvariant ranking, additional criteria are included: simultaneous growth in >2 distinct geographic locations, mutations in different regions of the spike , their potential effect on protein structure (by modeling), and the reemergence of individual mutations in novel combinations.The University of California Riverside School of Medicine team, led by author A.G., uses relative growth in the prevalence of specific substitutions and deletions/insertions, which are mapped onto Pango lineages or used to define new ones, identifying the fastest growing variants and mutation combinations within these lineages. Although the main focus has been on spike mutations, nonspike mutations are also tracked. These criteria are automated and available from a regularly updated website  binding, or if the position is located within the NTD supersite or the furin cleavage site  and by considering structural reasoning. This information is jointly considered when determining the importance of each mutation. The emphasis is primarily on substitutions in RBD and the mechanism around ACE2 binding and secondarily on NTD and proximity to the furin cleavage site. These substitutions are given higher priority if they are clearly transmitting faster and if they are in a different Barnes class from substitutions previously seen in the same lineages but are given lower priority if they have already been characterized.The Broad Institute team, led by author J.L., believes, like the University of California-Riverside School of Medicine team, that the accelerated growth of a lineage relative to its peers, across multiple geographic regions, is the single most important marker of lineages of potential concern. The team has developed 2 related approaches for identifying such lineages. The first approach fits a binomial logistic regression to the proportion of each lineage over time in every state. The team then systematically compares the growth rate of every lineage in each state, relative to all other lineages, and identifies lineages that are consistently increasing in multiple states . The identification of contact sites is performed to upweight substitutions at relevant antibody binding sites with recent changes in frequency. Several tools enable tracking of variants of concern and mutations of interest at global, regional, and country levels on a weekly basis by using data from the previous 3 months. An open-build using data from GenBank is available  for each antibody are computed for each specific mutation within its contact footprint, by using FoldX  were sporadically identified , Mu (in July 2021), and Omicron as an emergency update (between the November and December 2021 prioritizations). Indeed, the usefulness of the rankings has increased over time; Omicron lineages BA.2 and BA.5 have diversified into a wide range of sublineages, which have been epidemiologically successful (showing growth in numerous locations) and often show considerable immune escape, making them key lineages to track for vaccine effectiveness purposes  have emerged while another lineage has dominated global circulation. During the period of Alpha and Delta circulation, focus was placed on subvariants of those lineages containing a small number of additional substitutions. Although this focus was in part to enable experimental work to enhance scientific understanding of SARS-CoV-2 phenotypic variation, we suspected that the next dominant strain might have been produced by refinement of the current dominant strain, through addition of further fitness-enhancing substitutions. Our suspicion was based on 2 reasons: first, fitness-enhancing substitutions are likely to appear first in the dominant strain because of its greater circulation; and second, the rapid expansion of Alpha and then Delta demonstrated fitness advantages over the previously circulating strain. Substitutions arising in other strains would need to first overcome this fitness deficit and would be outcompeted by a sublineage of the dominant strain containing the same substitution, disregarding potential epistatic effects.In reality, emergence of Delta and Omicron has shown that the next dominant strain is not always produced by incremental refinement of the current dominant strain. Whether SARS-CoV-2 will continue to evolve in this fashion is unclear, particularly given the success of numerous more incremental subvariants of Omicron BA.2 and BA.5, which more closely follow the pattern we were preparing for during circulation of Alpha and Delta. Regardless of which of those patterns governs SARS-CoV-2 evolution in the long term, continued surveillance is needed to identify variation within the currently dominant lineage and to detect highly divergent sequences, which may be particularly likely to originate from countries in which a smaller proportion of cases are sequenced, which may harbor substantial unsampled variation; in Delta and Omicron, the emergent lineage was first identified in a country that performed minimal sequencing (Omicron in Botswana) or minimal sequencing relative to circulation (Delta in India).The prioritizations made by the 9 laboratories that form the NIH Early Detection team have been a valuable resource for helping experimental groups keep up to date with the rapid evolution of SARS-CoV-2. The NIH Early Detection team will continue to refine the methods used by individual subgroups to prioritize variants and the way in which this information is presented to experimental collaborators.US National Institutes of Health SARS-CoV-2 assessment of Viral Evolution Early Detection prioritization summary.US National Institutes of Health National Institute of Allergy and Infectious Diseases SARS-CoV-2 assessment of Viral Evolution Early Detection consortium prioritization of variant rankings for November 2022–February 2023.Additional information for US National Institutes of Health prioritization of SARS-CoV-2 variants.


As in many mammalian behaviors, sexual behavior exhibits structure. Each modular components of the structure, that are linked together over time, occur in probabilistic manner. Endocrine milieu, in particular sex hormones, define the probability to synchronize the behavior with the production of gametes. Developmental experience and environmental cues affect the hormonal milieu of the brain. This is especially true in female mammals, in which ova mature with certain intervals along with ovarian secretion of sex hormones. Estrogens secreted by mature ovarian follicles support both affiliative and executive components of female sexual behavior. In the absence of the ovarian steroids, females avoid males when possible, or antagonize and reject males when put together. Female sexual behavior is intimately linked with the estrous cycle in many species such that females are only receptive for a brief period at the estrus stage surrounding ovulation. Thus, in the rat, females strongly influence the outcome of mating encounter with a male. Affiliative or solicitatory behavior shown by females in estrus leads to the female adapting the lordosis posture, which is characterized by hindleg postural rigidity and lordotic dorsiflexion of the spine, in response to touch-pressure somatosensory stimuli on the skin of the flanks, rump-tail base, perineum region given by male partner. The posture facilitates intromission and consequently fertilization. Although dependence on estrogens is the most important feature of female rat sexual behavior, cervical probing combined with palpation of the hindquarter skin acts as a supranormal stimulus to elicit lordosis. Thus, lordosis behavior is a hub of multi-tiered, chronologically arranged set of behaviors and estrogen appear to alter excitability of neural network for lordosis. The lordosis reflex, dorsiflexion of the vertebral column Fig. , is an eAn earlier study by Barfield and Chen  showed sIn contrast to the tardive response to VMH stimulation, electrical stimulation of the midbrain central gray (CG) caused a prompt and transient facilitation of lordosis . The CG + currents 63]. The The POA contains a separate pool of neurons that promote proceptivity in addition to those that inhibit the receptivity. In particular, the excitability of POA neurons with axons to the VTA diminishes following estrogen in a sexually dimorphic pattern, in parallel to the capability of this steroid to induce the receptivity , 17.The VTA is one of the major terminal fields of estrogen-concentrating POA neurons . ElectriThe inhibition of proceptivity and receptivity obtained by electrical stimulation of focus of ibotenic acid lesion in the POA is due to the activation of fibers of passage which survived the excitotoxin challenge. In the lesioned animals, further transection to remove the POA afferents nullified the focal stimulation effect. The transaction was similar as the dorsal deafferentation of the POA by  which faThe inhibitory effect of the septum on the lordosis reflex has been recognized , 74. TheWhile anestrous female rats consistently avoid males, females in estrous approach and provoke males to initiate mounting. The series of affiliative or solicitatory behavior in females includes peculiar pattern of increased locomotor activity often called hopping and darting in front of the males. Increased locomotor activity in female rats in estrus embodies enhanced sexual motivation –81. EstrThe medial POA has been positively identified as a site for estrogen-induced activation of wheel running  while thThe opposite effects of estrogen on the medial and lateral POA neurons are reminiscent of our other observations. Estrogen decreased antidromic activation thresholds in axons in the CG with origins in the VMH , but inc+,K+-transporting adenosine triphosphatase in the medial basal hypothalamus while it suppressed the activity in the POA [+ channels [2+ mobilization, and arachidonic acid metabolism [Estrogen-induced changes in the axonal excitability occur in long time-courses, which implicate the involvement of receptor-mediated, genomic activation . Both th the POA . The eff the POA . This en the POA . In rat channels . Estrogetabolism . With whtabolism .Sexual behavior is a multitiered set of components which occur sequentially under the influence of sex hormones, particularly estrogen in female rodents. This characteristic has been thoroughly utilized in studies to identify and analyze neural mechanism for the behavior. Thus, separate neuronal circuitries, inter alia, those that promote or suppress each of proceptive and receptive component of sexual behavior have been shown. This multiplicity contributed to confusions in the interpretation of the results of studies which employed focal brain stimulation or lesion. For example, systemic administration of subthreshold dose of estrogen was needed to obtain enhanced lordosis from local implants of estrogen crystals in the VMH  or elect


Arabidopsis thaliana root commensals showed that these exometabolites possess a root niche-specific function in establishing root competence and inducing anticipated changes in root surroundings. Both biosynthetic operons are abundant in roots in natural habitats, indicating that these exometabolites co-functioning is an adaptive feature that helps Pseudomonad dominate the root microbiota.The majority of the root microbiota formation derives from soil-dwelling microorganisms. The limited extent of thorough investigation leads to a dearth of knowledge concerning the intricate mechanisms of microbe-microbe interaction implicated in the establishment of root microbiota. Therefore, the taxonomic signatures in bacterial inhibition profiles were determined by in vitro testing of 39,204 binary interbacterial interactions. However, findings from genetic and metabolomic studies elucidated that co-functioning of the antimicrobial 2,4-d iacetylphloroglucinol (DAPG) and the iron chelator pyoverdine as exometabolites has significantly contributed to the potent inhibitory activities of the highly antagonistic Pseudomonas brassicacearum R401. Microbiota restoration with a core of  Ralstonia solanacearum (Rs) is attributed to its ability to sequester inorganic iron through the use of siderophores, which limits the availability of this essential nutrient to other microorganisms . Root microbiota formation was shown to be supported by the antibiotics DAPG and pyoverdine (the high-affinity iron chelator), both of which were found by Getzke and co-workers as exometabolites underlying the actions of the highly hostile Pseudomonas brassicacearum R401.Root microbiota, the community of bacteria underneath plant roots, is characterised by low taxonomic diversity and dominant taxonomic classes . The dominant manifestation of inhibitory activities was observed by bacterial strains of three distinct genera: Pseudomonas, Streptomyces, and Bacillus.They examined the pervasiveness of interbacterial competition initiated by secreted metabolites by analysing 39,204 binary interbacterial interactions, comprising 198 producers and 198 target isolates. All tested bacterial classes exhibited antagonistic interactions, suggesting that the formation of exometabolites is ubiquitous around the At-Sphere culture database of commensals  to the biosynthesis of pyoverdine and Rs inhibition in R401  were incapable of producing pyoverdine. Getzke et al.  exhibited severely rebated inhibitory activity against Rs in comparison to the single mutants, justifying the concurrent influence of two metabolites. DAPG and pyoverdine jointly accounted for > 70% of the inhibitory activity of R401, but the presence of an inhibition residual halo pointing to another exometabolite has yet to be defined. The influence of DAPG and pyoverdine on the structure of root microbiota and Rs growth was studied by reconstitution experiments , justified by deficient root samples Rs relative abundances. Relative isolate abundances were inspected to determine physiological relevance in planta, and this study determined that the disruption of the associated BGCs in R401 only benefited DAPG- and/or pyoverdine-sensitive isolates. This particular observation has prompted the need to examine the impact on both community-level effects and individual isolates. The average decrease in inhibitory activity was observed across all R401 mutants. As a result, pairwise in vitro interaction experiments can correlate with the impact of two exometabolites produced by a single isolate on a taxonomically diverse SynCom's key ecological indices.A genetic screen was used to find out what was going on with the residual inhibitory effect of R401 e et al.  postulatPseudomonas strains in natural soils was assessed to check their capability of producing DAPG and pyoverdine. The genomes of multiple commensal culture collections isolated from the roots or leaves of A. thaliana or the roots of the legume Lotus japonicus unleashed that root-derived Pseudomonas isolates had a greater abundance of DAPG and pyoverdine BGCs. The findings presented in this study corroborate the conclusions drawn from our obtained outcomes of specific gnotobiotic A. thaliana and core commensal communities and indicate a more comprehensive root-specific function of the two exometabolites in natural environments above the crucifer model. In summary, the integration of high-throughput binary interaction studies with genome mining for BGC collections of root microbiota can be used to detect strains that exhibit broad-spectrum antagonistic activities and are potentially potent root colonizers. This could have implications for future interventions using rational biologicals to intervene in the root microbiome in order to impart positive features on the host, such as indirect pathogen defence and better mineral nutrition.The relative abundance of R401 in SynCom samples from root and soil compartments determined the influence of R401-mediated bacterial assembly modulation and diversity on the competitiveness of R401. The findings indicated that DAPG and pyoverdine serve as root competence determinants of R401, particularly in competing with other SynCom members within the root compartment. Furthermore, the frequency of plant-associated


Mature teratoma is a benign neoplasm, mostly composed of well-differentiated derivations of almost two or three germ cell layers, while immature teratoma is a malignant neoplasm composed of immature neural and embryonic tissue. Immature teratoma in the context of ovarian endometrioma has not been reported yet.A 34-year-old woman with primary infertility is reported in this study who suffered from immature teratoma associated with ovarian endometrioma. After several rounds of fertility treatment, the patient was referred for severe abdominal pain and underwent emergency surgery for the rupture of ovarian endometrioma. To preserve the ovary, the cyst was not resected in areas attached to the ovary. Some months later, the patient noticed a progressive abdominal enlargement. The sonographic evaluation revealed multiple solid-cystic lobulated masses on the abdominal wall and throughout the pelvic cavity. The histologic diagnosis was consistent with immature teratoma. The patient was treated with high-dose neoadjuvant chemotherapy and fertility-sparing surgery (FSS). The histologic evaluation of the extracted masses revealed teratoma maturation.This study reveals the importance of complete removal of endometrioma and highlights the role of neoadjuvant chemotherapy in fertility-sparing surgery and potentiating teratoma maturation. Endometriomas are benign and common ovarian cysts that are found in 15–42% of females suffering from endometriosis , LH (11.1 mIU/ml), HE4 (63.2 ng/ml), and AMH (5.13 ng ml), and elevated CA-125 (371.1 U/ml) and ROMA-index (14.6%). The patient underwent hysterosalpingography to detect the cause of infertility, which was normal with no blockage in the fallopian tube and uterus. The patient received several courses of letrozole that were not effective in the treatment of infertility.This case was presented in March 2022 in Firouzgar Hospital of Iran University of Medical Sciences. A 34-year-old female nurse, with a history of dyspareunia and dysmenorrhea and a diagnosis of primary infertility, was referred to a gynecologist for the treatment of her symptoms. The patient had normal FSH (6.3 mm) with volume of 400 ml in the midline position of the pelvic, raising the probability of ovarian torsion. The amount of free fluid around the cyst was about 85 ml. The patient underwent an emergent operation for the rupture of ovarian endometrioma which spread throughout the abdominal cavity. The surgery was done by a general gynecologist. In order to preserve the ovary for future ovulation and pregnancy, the surgeon did not resect the cyst in areas firmly attached to the ovary. After the left ovarian cystectomy, an abdominal drain was placed and the patient was discharged afterward. The histologic examination of the tissue specimen from the cyst wall was consistent with the diagnosis of endometrioma.Almost five months later, the patient was referred to the emergency department of a teaching hospital with severe abdominal pain. The sonographic evaluation revealed a very large cystic lesion (74*95*108 mm) with an echogenic center of 25 mm, without internal blood flow. Furthermore, moderate ovarian attachment to the uterus and bilateral uterosacral ligament thickening were noticed. The patient received high-dose of medication for ovulation induction  for 12 days. From the first days of medication, the patient felt the presence of a progressively growing palpable cyst in the exact site of the previous abdominal drain. However, the doctor assured her that they are endometriosis nodules in the abdominal wall and are nothing to be concerned about. She only performed follow-up vaginal sonographic evaluations which showed the adequate size and number of follicles in both ovaries. Therefore, the ovarian puncture was performed as planned. However, no abdominal sonographic evaluation was performed to investigate the abdominal wall nodules.Almost two months later, the patient was referred to an obstetrician and gynecologist for an infertility problem. Before ovulation induction, a sonographic evaluation was done, which showed an endometrioma in the left ovary . The patient underwent a biopsy. Histologic evaluation of the biopsy sample showed immature neuroglial tissue and neuroepithelial rosettes in the context of cellular stroma, consistent with the diagnosis of immature teratoma  regimen. The chemotherapy of the patient was associated with numerous complications including chemotherapy-induced neuropathies and several infections leading to hospitalization. Three months after chemotherapy, the patient was elected for surgical debulking of tumors of the abdominal wall and pelvic cavity by a gynecologist and a surgical oncologist. Due to the wide adhesion of the tumor to the abdominal wall, a substantial part of the abdominal wall was resected. The debulking of multiple huge abdominopelvic tumors of about 10*20 teratoma . Two dayAfter the operation, the patient had some difficulties doing her routine activities such as walking, which required several occupational therapy sessions. During the three months of follow-up, the patient required two further surgeries for the repair of the implanted meshes in the abdominal wall. No sign of recurrence was observed until the last follow-up.Malignant germ cell tumors are rare and mostly involve females in their reproductive years. Surgery is the first and most important option in the treatment of malignant germ cell tumors. Fertility-sparing surgery that allows preserving one ovary and the uterus has shown long-term safety for young women seeking future pregnancy and is also effective in preventing early menopause. However, recent evidence suggests avoiding FSS in cases with an increased risk of peritoneal adhesions .Immature ovarian teratoma is a rare germ cell tumor with challenging diagnosis and treatment . Its conWhile the role of extensive surgery is acknowledged for the treatment of ovarian germ cell tumors, there is no consensus on the timing of chemotherapy . AdjuvanAltogether, the present report reveals that complete removal of endometrioma overweighs preserving fertility because mismanagement of endometrioma could be associated with subsequent devastating outcomes. In addition, the present case highlights the role of neoadjuvant chemotherapy in the management of ovarian immature teratoma, by increasing the feasibility of fertility-sparing surgery and the possibility of teratoma maturation.


Over the past 70 years, significant progress has been made in understanding the molecular and cellular mechanisms of inflammation and tissue regeneration. This has become most evident in the last 20 years when revolutionary techniques in biology have exponentially increased the number of publications in the field. Following tissue damage caused by infection, mechanical or toxic injury, or autoimmune diseases, the healing process involves a series of highly regulated molecular and cellular processes that lead to the restoration of tissue homeostasis. If any step in the regeneration process is dysfunctional, chronic inflammation, tissue fibrosis or tumor formation can develop .There are three overlapping steps in wound healing: (1) coagulation and inflammation, then 2) the proliferation and formation of new tissue, and 3) finally the tissue remodeling [ the prol finally The role of immune cells, in particular macrophages, in the inflammatory process has long been known, but it has recently been discovered that these immune cells also play an important role in the second and third stages of tissue regeneration ,9,10,11.Several interesting findings and overviews were shortly mentioned to illustrate molecular and cellular actors involved in inflammation and tissue regeneration.Rangarajan and co-workers (2022) reviewed the effects of different pro-resolving mediators on atherosclerosis . AtherosDurand and co-authors (2022) investigated the osteogenic effects of two different biomaterials (metakaolin and polymethylmethacrylate) in the Masquelet-induced membrane in a rat model animal . They shSpinal cord injury often causes paralysi and currently no therapy is available. Following injury, nerve and glial cells die as a result of inflammation. In addition, activation of microglial cells and infiltration of macrophages and lymphocyte cells can be observed in the injured tissue. Wu and colleagues (2022) showed that the bile acid tauroursodeoxycholic acid (TUDCA) was able to inhibit inflammation and promote the temporary recovery of motor function in rats . UnfortuToll-like receptor 8 (TLR8), localizes in the endosome, is able to bind to single-stranded RNAs of viral and bacterial origin. In human monocytes and macrophages, pro-inflammatory cytokines and type I interferons are secreted in response to the binding. Nilsen and colleagues 2022) investigated this mechanism [22 invest2O3 NPs) are one of the most frequently produced particles in the world. Dekali and colleagues (2022) reviewed the current knowledge on the effects of Al2O3 NPs on animal health [2O3 NPs have been shown to significantly increase the risk of inflammation, pulmonary fibrosis, reduced lung function, and increased risk of lung cancer in the lung parenchyma of various animals. In contrast, in vitro studies on the effects of Al2O3 NPs on lung cells have been rather controversial.Alumina nanoparticles  analyzed the long-term effects of 4′-nitrophenyl isopropyl methyl phosphonate (NIMP), a sarin surrogate [ analyzedThe development of inflammatory and tissue regeneration disorders is largely due to an imbalance between reactive oxygen species (ROS) and endogenous antioxidants. Perez and colleagues (2022) reviewed the relationship between the effects of antioxidants on neuronal remyelination and muscle regeneration . In summHart and Nakamura (2022) reviewed the most important cell therapy methods for the regeneration of damaged musculoskeletal tissue . The celFailure of tissue regeneration can have serious clinical consequences, such as tumor formation because proteins and cells involved in signaling mechanisms that are important for healing are also involved in cancer metastasis. In their review, Lopez and colleagues 2022) compared the relationship between wound healing and metastasis [022 compaIn our laboratory, we have investigated a method to identify mRNA transcripts in cryosections of undecalcified rat bone. In collaboration with the Institute of Plant Sciences of Paris-Saclay (IPS2), in situ hybridization and hybridization chain reaction (in situ-HCR) was adaptedto better understand gene expression in in situ bone tissue . Our objAs the phenotype of in vivo macrophages is still poorly understood, we used the above techniques to identify in vivo macrophages in regenerating bone . There iUnderstanding the mechanisms of inflammation and tissue regeneration is of great scientific and clinical importance. However, the molecular and cellular mechanisms through which they exert their effects are still largely unknown. The study of these processes is essential for the development of therapeutic strategies aimed at tissue repair. We hope that readers of this special issue of Biomedicines will enjoy reading the excellent papers of many of the leading scientists in the field. We hope also that future generations of researchers will be inspired by the topics published in this special issue to further improve our knowledges in this field.