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Studies have demonstrated the importance of the gut microbiota during pregnancy, and there is emerging literature on the postpartum maternal gut microbiota. The primary objective of this paper was to synthesize the literature on the postpartum gut microbiome composition and diversity measured in stool samples from healthy mothers of predominantly term infants. The secondary objectives were (1) to identify biological and environmental factors that influence postpartum maternal gut microbiota and (2) to assess health conditions and clinical intermediate measures associated with postpartum gut microbiota changes in all mothers. Electronic searches were conducted November 9, 2020 and updated July 25, 2021 without publication time limits on PubMed, Embase, CINHAL, Scopus, Cochrane Library, BioArchives, and OpenGrey.eu. Primary research on maternal gut microbiota in the postpartum (up to one year after childbirth) were eligible. Postpartum gut microbiota comparisons to pregnancy or non-pregnancy gut microbiota were of interest, therefore, studies examining these in addition to the postpartum were included. Studies were excluded if they were only conducted in animals, infants, pregnancy, or microbiome of other body locations (e.g., vaginal). Data extraction of microbial composition and diversity were completed and synthesized narratively. Studies were assessed for risk of bias. A total of 2512 articles were screened after deduplication and 27 were included in this review. Of the 27 included studies, 22 addressed the primary objective. Firmicutes was the predominant phylum in the early (

The overset grid method for simulation of unsteady flow with moving bodies faces several issues, including low assembly efficiency for a large number of bodies, difficult parallel implementation, and the requirement of manual intervention. To address these issues, in this paper, we develop an efficient, automatic, and robust parallel dynamic overset-unstructured-grid assembly method. It is achieved by parallelizing its two main steps: hole cutting, and identification of interpolation stencils. The hole cutting is simply implemented in parallel by identifying the active zone of each grid with a criterion of the global minimum wall distance. The global minimum wall distance is efficiently calculated on each process with the oriented-bounding-box-based [Formula: see text]-dimensional ([Formula: see text]-D) trees of the wall surface grids. For identification of the interpolation stencil, we use the results of the first step, optimally define the interpolation boundary nodes, and determine their candidate donor partitions in each process. This efficiently minimizes the number of query nodes and their donor cell candidates. The donor cell search is efficiently performed in parallel in each candidate donor partition by using the oriented-bounding-box-based [Formula: see text]-D tree of the field volume grid. Several cases are adopted to test the efficiency and capability of the proposed parallel dynamic overset-unstructured-grid assembly approach.

Objective. The objective is to evaluate the clinical efficacy of cross electro-nape-acupuncture (CENA) in the treatment of pseudobulbar palsy in patients with tracheotomy intubation for severe cerebral haemorrhage and to provide an innovative acupuncture method for the treatment of such patients. Methods. A total of 126 patients from six trial centres who met the inclusion criteria were randomly divided into three groups according to the random number table method in the ratio of 1 : 1 : 1, with 42 patients in each group, and the three groups were divided into CENA group, electro-acupuncture group, and acupuncture group. Each group’s acupuncture treatment lasted for 30 minutes, and the needles were removed at the end of the treatment. Acupuncture was performed once a week on Sunday only and twice a day from Monday to Saturday, a total of 4 weeks of treatment. The SWT, FDA, ChSWAL-QOL, and TCRGS scores of the three groups of patients before and after treatment were compared to evaluate the effect of CENA on remodelling the function of swallowing reflex and cough reflex and promoting the recovery of dysarthria and swallowing quality of life in pseudobulbar palsy in patients with tracheotomy intubation for severe cerebral haemorrhage. Results. After treatment, the WST and TCRGS grade scores decreased and the FDA and ChSWAL-QOL scores increased significantly in all three groups compared with the pretreatment scores and were statistically significant. There was a significant difference between the three groups for these four indicators after treatment; the comparison between groups showed significant differences in the CENA group compared to the electro-acupuncture and acupuncture groups. The efficiency of the CENA group was significantly better than that of the electro-acupuncture and acupuncture groups. Conclusion. Compared with the acupuncture and electro-acupuncture groups, the CENA could better promote the remodelling of swallowing function and cough reflex function, promote the recovery of dysarthria, and better improve the quality of life of patients with pseudobulbar palsy from tracheotomy intubation in severe cerebral haemorrhage.

Weathering occurs when glass interacts with the atmosphere. Ancient glass is susceptible to the influence of the burial environment. In the process of glass weathering, its composition ratio will be changed due to a large number of internal elements and environmental elements exchange. In this paper, Fisher's exact test and frequency analysis are used to test the glass pattern, type, color, and surface weathering respectively, and the conclusion is that there are significant differences between glass type and surface weathering, while there are no significant differences between pattern, color, and surface weathering. Then, the CART decision tree algorithm was used to classify the glass into weathered and unweathered, and a binary tree was established with 14 chemical components as characteristics. The average chemical composition of all the sampling points in the sibling nodes of the node where the weathering point is located was used as the predictive value of the chemical composition before the weathering point. Finally, the correlation analysis of the chemical constituents of high potassium glass and lead barium glass was carried out by hierarchical clustering method. In a high-potassium glass, silica is one category, and other chemical components are another category. In a lead-barium glass, silica and lead oxide are one category, and other chemical components are another category. Therefore, it can be considered that the chemical composition relationship of lead-barium glass is more complex.

This paper focuses on the composition analysis and type identification of ancient glass objects. This paper establishes a judgment model based on the surface characteristics of cultural relics samples, and analyzes the classification laws of high-potassium glass and lead-barium glass; then, the samples of the same category are classified into subclasses according to K-Means method, Gaussian mixture method (GMM) and Mini-Batch K-Means method, and according to each evaluation method, the K-Means method is chosen comprehensively to establish The K-Means method was used to establish a clustering model for glass samples, and the results of subclass classification under each category were obtained. Based on the composition and surface characteristics of the samples, descriptive statistics, scatter plots, S-W test and Pearson correlation coefficient were used to analyze the correlations of chemical compositions among samples of different categories; then, based on the subclass classification made in Problem 2, the differences of the correlations among samples of different categories of artifacts were analyzed using the methods of correlation analysis and difference analysis based on different ranges of data sets.

The Silk Road was an important channel for trade and commerce between East and West in ancient times, and an important link for cultural exchange between East and West, playing an important role in the development of ancient civilization and history. Glass was one of the important goods carried on the Silk Road in ancient times. In this paper, focus on the problem of component analysis and type identification of ancient glass products. This paper extracted the important factors of the data by PCA principal component analysis, reduced the 14-dimensional data to two dimensions, then built a data point distribution map by visualization, and established a linear classification model based on SVM support vector machine. After that, the model is used to identify the type of samples based on the underlying data. The sensitivity indices of each factor were solved by using Sobol method for the sensitivity analysis of the results.

The break events of the western North Pacific summer monsoon vary significantly in duration, ranging from a few days to more than 2 weeks. In this study, we classify the monsoon break events into short-lived (≤8 days) and long-lived (>8 days) events, which account for 78% and 22% of the total events during 1979–2020, respectively. The results show that convection suppression is stronger and broader for long-lived events than for short-lived events. In addition, the temporal distributions of the two break categories are distinct: short-lived events present a roughly even distribution from late July to late September, while long-lived events are highly concentrated, with a striking frequency peak around early September. The mechanisms responsible for break events are investigated. Results indicate that both break categories are co-contributed by 10–25- and 30–60-day oscillations. Short-lived events result from a phase lock of the two oscillations, which explain 54% and 35% of the convection suppression, respectively. By contrast, long-lived events are initiated by both oscillations but maintained only by 30–60-day oscillations. In addition, 30–60-day oscillations reach the peak intensity after the monsoon onset due to seasonal background changes, which is critical for forming the frequency peak of long-lived events around early September. Furthermore, it is found that long-lived events tend to occur in the developing phase of positive SST anomalies in the tropical central Pacific, when 30–60-day oscillations are abnormally enhanced over the western North Pacific. Significance Statement The monsoon break usually refers to significant rainfall reduction during the monsoon season, which can induce abnormal weather, such as heatwaves and droughts, resulting in huge economic losses. To date, however, there are only a few studies on the break of the western North Pacific summer monsoon (WNPSM), in sharp contrast to the well-known Indian monsoon break. We note that break events of the WNPSM vary widely in duration. This study aims to reveal the remarkable difference between short- and long-lived events, including intensity, spatial extent, occurrence time, and physical mechanisms. These results will help us better understand the diversity of the break phenomenon and may serve as a scientific basis for improving the subseasonal prediction of the WNPSM.

Camouflaged object detection (COD) is important as it has various potential applications. Unlike salient object detection (SOD), which tries to identify visually salient objects, COD tries to detect objects that are visually very similar to the surrounding background. We observe that recent COD methods try to fuse features from different levels using some context aggregation strategies originally developed for SOD. Such an approach, however, may not be appropriate for COD as these existing context aggregation strategies are good at detecting distinctive objects while weakening the features from less discriminative objects. To address this problem, we propose in this article to exploit frequency learning to suppress the confusing high-frequency texture information, to help separate camouflaged objects from their surrounding background, and a frequency-based method, called FBNet, for camouflaged object detection. Specifically, we design a frequency-aware context aggregation (FACA) module to suppress high-frequency information and aggregate multi-scale features from a frequency perspective, an adaptive frequency attention (AFA) module to enhance the features of the learned important frequency components, and a gradient-weighted loss function to guide the proposed method to pay more attention to contour details. Experimental results show that our model outperforms relevant state-of-the-art methods.

Electric double layer (EDL) gating can induce large capacitance densities (∼1−10 μF/cm^2) in two-dimensional (2D) semiconductors; however, several properties of the electrolyte limit performance. One property is the electrochemical activity which limits the gate voltage (VG) that can be applied and therefore the maximum extent to which carriers can be modulated. A second property is electrolyte thickness, which sets the response speed of the EDL gate, and therefore the timescale over which the channel can be doped. Typical thicknesses are on the order of microns, but thinner electrolytes (nanometers) are needed for very-large-scale-integration (VLSI) both in terms of physical thickness and the speed that accompanies scaling. In this study, finite element modeling of an EDL-gated field-effect transistor (FET) is used to self-consistently couple ion transport in the electrolyte to carrier transport in the semiconductor, in which density of states, and therefore, quantum capacitance is included. The model reveals that 50 to 65% of the applied potential drops across the semiconductor, leaving 35 to 50% to drop across the two EDLs. Accounting for the potential drop in the channel suggests that higher carrier densities can be achieved at larger applied VG without concern for inducing electrochemical reactions. This insight is tested experimentally via Hall measurements of graphene FETs for which VG is extended from ±3 to ±6 V. Doubling the gate voltage increases the sheet carrier density by an additional 2.3×10^13 cm^−2 for electrons and 1.4×10^13 cm^−2 for holes without inducing electrochemistry. To address the need for thickness scaling, the thickness of the solid polymer electrolyte, polyethylene oxide (PEO):CsClO_4, is decreased from 1 μm to 10 nm and used to EDL- gate graphene FETs. Sheet carrier density measurements on graphene Hall bars prove that the carrier densities remain constant throughout the measured thickness range (10 nm−1 μm). The results indicate promise for overcoming the physical and electrical limitations to VLSI while taking advantage of the ultrahigh carrier densities induced by EDL gating.

This study aimed to establish a collaborative approach to quantify local HIV transmission, which is an issue of great concern to public health.We linked HIV-1 pol gene sequences to demographic information and epidemiological investigations in Hangzhou (a central city in East China). We estimated local acquisition rates from collaboration of molecular network analysis (with a distance-based approach) and epidemiological investigations.Among 1064 newly diagnosed HIV patients, 857 pol sequences were acquired and subsequently analysed. Multiple subtypes were identified, with CRF07_BC (42.5%) and CRF01_AE (39.2%) predominating, followed by 13 other subtypes and 26 unique recombinant forms (URFs). By integrating the molecular network analysis and epidemiological investigations, we estimated that the proportion of local infection was 63.2%. Multivariable analyses revealed that individuals in clusters were more likely to be local residents, 50 years old or older, farmers, and to have a higher first CD4 count level (P0.05). Proportions of local acquisitions over 70% were observed in local residents (79.9%, 242/303), individuals 50 years old or older (73.6%, 181/246) and farmers (75.6%, 99/131).Molecular network analysis can augment traditional HIV epidemic surveillance. This study establishes a paradigm for quantifying local HIV transmission for generalization in other areas.

This study aimed to examine the association of bullying victimization with anxiety and depressive symptoms among Chinese adolescents and explored the role of coping styles in the foregoing associations.Data were drawn from the 2019 School-based Chinses Adolescents Health Survey (n = 19,809). Information about bullying victimization, coping styles, anxiety symptoms, and depressive symptoms were measured. Linear mixed-effects models were performed.After adjusting for covariates, verbal victimization (β = 1.94 for anxiety symptoms; β = 4.62 for depressive symptoms), relational victimization (β = 3.40 for anxiety symptoms; β = 8.37 for depressive symptoms), physical victimization (β = 2.63 for anxiety symptoms; β = 6.07 for depressive symptoms) and cyber victimization (β = 4.68 for anxiety symptoms; β = 10.72 for depressive symptoms) were associated with anxiety and depressive symptoms. Moreover, the severity of anxiety and depressive symptoms tended to increase with the number of victimization types. The interaction effects between bullying victimization and coping style on anxiety and depressive symptoms were significant. Further stratified analyses by coping styles indicated that the association of relational and cyber victimization on anxiety and depressive symptoms were significantly stronger in adolescents with negative coping style than in those with positive coping style.Causal inference is limited due to the cross-sectional design.Bullying victimization is associated with anxiety and depressive symptoms, and coping styles may play a moderate role in these associations. Interventions to promote mental health could focus on developing positive coping styles, particularly among adolescents with bullying victimization.

Facing the problem of increased production of deep tight gas reservoirs, this study takes the Dibei gas reservoir in Tarim Basin as an example, carries out geomechanical research, and reveals the rock mechanical properties, in situ stress, and fracture characteristics of the tight reservoir. From the perspective of the in situ stress field and the effectiveness of fractures, the study reveals their impacts on reservoir quality, wellbore stability, and fracturing networks. The results show that the in situ stress and the effectiveness of fracture mechanics under its control have obvious control over the production capacity in the Dibei gas reservoir. The positions and intervals with low in situ stress, high fracture density, and fracture effectiveness are often favorable parts. A directional well has the dual advantages of overcoming reservoir heterogeneity and safety and stability. Understanding the geomechanical characteristics can quantitatively optimize the best wellbore trajectory, reduce the difficulty of fracturing from the source of well location deployment, improve the efficiency of hydraulic fracturing, and then realize the stimulation of gas reservoirs. In addition, the favorable borehole trajectory considers both the sweet spot penetration and borehole wall stability, which will reduce the difficulty of fracturing and is conducive to the efficient stimulation of tight gas reservoirs. Geomechanics research has built an integrated bridge between geology and engineering, which plays a significant role in increasing gas production.

Mirrors are everywhere in our daily lives. Existing computer vision systems do not consider mirrors, and hence may get confused by the reflected content inside a mirror, resulting in a severe performance degradation. However, separating the real content outside a mirror from the reflected content inside it is non-trivial. The key challenge is that mirrors typically reflect contents similar to their surroundings, making it very difficult to differentiate the two. In this article, we present a novel method to segment mirrors from a single RGB image. To the best of our knowledge, this is the first work to address the mirror segmentation problem with a computational approach. We make the following contributions: First, we propose a novel network, called MirrorNet+, for mirror segmentation, by modeling both contextual contrasts and semantic associations. Second, we construct the first large-scale mirror segmentation dataset, which consists of 4,018 pairs of images containing mirrors and their corresponding manually annotated mirror masks, covering a variety of daily-life scenes. Third, we conduct extensive experiments to evaluate the proposed method and show that it outperforms the related state-of-the-art detection and segmentation methods. Fourth, we further validate the effectiveness and generalization capability of the proposed semantic awareness contextual contrasted feature learning by applying MirrorNet+ to other vision tasks, i.e., salient object detection and shadow detection. Finally, we provide some applications of mirror segmentation and analyze possible future research directions. Project homepage: https://mhaiyang.github.io/TOMM2022-MirrorNet+/index.html .

Background Rapid and efficient strategies are needed to discover neutralizing antibodies (nAbs) from B cells derived from virus-infected patients. Methods Here, we report a high-throughput single-B-cell cloning method for high-throughput isolation of nAbs targeting diverse epitopes on the SARS-CoV-2-RBD (receptor binding domain) from convalescent COVID-19 patients. This method is simple, fast and highly efficient in generating SARS-CoV-2-neutralizing antibodies from COVID-19 patients’ B cells. Results Using this method, we have developed multiple nAbs against distinct SARS-CoV-2-RBD epitopes. CryoEM and crystallography revealed precisely how they bind RBD. In live virus assay, these nAbs are effective in blocking viral entry to the host cells. Conclusion This simple and efficient method may be useful in developing human therapeutic antibodies for other diseases and next pandemic.

There is a strong aerodynamic interference when launching the missile in the embedded mode. During the separation process, the carrier aircraft safety may be threatened due to large slenderness ratio, low structural stiffness, and aeroelasticity effects of the missile. The present study simulates missile separation in the presence of the aeroelasticity effects based on the computational fluid dynamics (CFD), rigid body dynamics (RBD), and computational structure dynamics (CSD) coupling method. A hybrid dynamic grid method consisting of the mixed overset unstructured grid and deformation grid is utilized. In order to verify the accuracy of the coupled numerical method, store separation from a wing and AGARD 445.6 wing flutter are first simulated as two standard test cases. The verification results imply that the present coupled numerical method is reliable and capable in simulation of the aeroelastic effect in missile separation. The influence of aeroelasticity on the separation trajectory of a missile from the internal bay is systematically studied at different states. Numerical results show that aeroelasticity substantially affects the missile angular displacement, while it has a slight impact on the linear displacement of the center of mass. Mach number and flight altitude are two important flight parameters that characterize the aeroelasticity effect on missile separation from the internal bay.