The Impact of the Risk Perception of COVID-19 PANDEMIC on College Students' Occupational Anxiety: The Moderating Effect of Career Adaptability

In order to understand the changes in college students' risk perception and occupational emotion under major public health events and to explore the influencing factors of college graduates' employment guidance, 578 college students were surveyed by questionnaire to explore the impact of the risk perception of COVID-19 pandemic on college students' occupational anxiety and its internal mechanisms, and to analyze the mediating role of psychological resilience in the impact and the moderating role of career adaptability. The results showed that: (1) there is a significant positive correlation between the risk perception of COVID-19 pandemic and occupational anxiety; there is a significant negative correlation between risk perception and psychological resilience; there is a significant negative correlation between the psychological resilience and occupational anxiety. (2) Psychological resilience plays a mediating role between risk perception and occupational anxiety. (3) Career adaptability plays a negative moderating role between the risk perception of COVID-19 pandemic and occupational anxiety. These results showed that the risk perception of COVID-19 pandemic not only directly aggravates college students' occupational anxiety, but also indirectly affects occupational anxiety through psychological resilience; Career adaptability significantly alleviats the incremental effect of the risk perception of COVID-19 pandemic on college students' occupational anxiety. This paper has positive enlightenment on how to improve the employability of college students and alleviate their employment anxiety during major public health events

Observer-based Leader-following Consensus for Positive Multi-agent Systems Over Time-varying Graphs

This paper addresses the leader-following consensus problem for discrete-time positive multi-agent systems over time-varying graphs. We assume that the followers may have mutually different positive dynamics which can also be different from the leader. Compared with most existing positive consensus works for homogeneous multi-agent systems, the formulated problem is more general and challenging due to the interplay between the positivity requirement and high-order heterogeneous dynamics. To solve the problem, we present an extended version of existing observer-based design for positive multi-agent systems. By virtue of the common quadratic Lyapunov function technique, we show the followers will maintain their state variables in the positive orthant and finally achieve an output consensus specified by the leader. A numerical example is used to verify the efficacy of our algorithms

Endoscopic and Angiographic Diagnosis and Management of a Gastric Arteriovenous Malformation

AbstractIntroductionGastric arteriovenous malformation (AVM) is an uncommon cause of upper gastrointestinal (GI) bleeding.Methods and resultsWe describe a case of gastric AVM which was diagnosed endoscopically and successfully managed by endoclip application and percutaneous transarterial coil embolization.ConclusionsWe propose that these two minimally invasive technologies can be used to manage AVM in the gut: endoscopic therapy to control luminal bleeding and interventional radiology to define the full extent of the malformation and to decrease arterial pressure and flow to the point that hemostasis can occur, without creating symptomatic ischemia

Recent Changes in Atmospheric Polycyclic Aromatic Hydrocarbons (PAHs) and Nitropolycyclic Aromatic Hydrocarbons (NPAHs) in Shenyang, China

Airborne particulates were collected in three size fractions by using Anderson low-volume air samplers in Shenyang, China, in winter and summer in 2007. Compared with data obtained in 2001 at the same sites, the total concentrations of nine polycyclic aromatic hydrocarbons (PAHs) in winter decreased by 67% at one site and decreased by 40% at the other site, while the total concentrations of four nitropolycyclic aromatic hydrocarbons (NPAHs) did not decrease. This suggests that environmental countermeasures begun in 2001 were effective in decreasing the concentration of PAHs. However, in summer, the concentrations of PAHs and NPAHs rose by the factors of 4 and 5, respectively, possibly because of an increase in the number of motor vehicles. © 2011 Taylor and Francis Group, LLC

Graphene/silicon heterojunction for reconfigurable phase-relevant activation function in coherent optical neural networks

Optical neural networks (ONNs) herald a new era in information and communication technologies and have implemented various intelligent applications. In an ONN, the activation function (AF) is a crucial component determining the network performances and on-chip AF devices are still in development. Here, we first demonstrate on-chip reconfigurable AF devices with phase activation fulfilled by dual-functional graphene/silicon (Gra/Si) heterojunctions. With optical modulation and detection in one device, time delays are shorter, energy consumption is lower, reconfigurability is higher and the device footprint is smaller than other on-chip AF strategies. The experimental modulation voltage (power) of our Gra/Si heterojunction achieves as low as 1 V (0.5 mW), superior to many pure silicon counterparts. In the photodetection aspect, a high responsivity of over 200 mA/W is realized. Special nonlinear functions generated are fed into a complex-valued ONN to challenge handwritten letters and image recognition tasks, showing improved accuracy and potential of high-efficient, all-component-integration on-chip ONN. Our results offer new insights for on-chip ONN devices and pave the way to high-performance integrated optoelectronic computing circuits

Glutamic Acid Decarboxylase-Derived Epitopes with Specific Domains Expand CD4+CD25+ Regulatory T Cells

BACKGROUND:CD4(+)CD25(+) regulatory T cell (Treg)-based immunotherapy is considered a promising regimen for controlling the progression of autoimmune diabetes. In this study, we tested the hypothesis that the therapeutic effects of Tregs in response to the antigenic epitope stimulation depend on the structural properties of the epitopes used. METHODOLOGY/PRINCIPAL FINDINGS:Splenic lymphocytes from nonobese diabetic (NOD) mice were stimulated with different glutamic acid decarboxylase (GAD)-derived epitopes for 7-10 days and the frequency and function of Tregs was analyzed. We found that, although all expanded Tregs showed suppressive functions in vitro, only p524 (GAD524-538)-expanded CD4(+)CD25(+) T cells inhibited diabetes development in the co-transfer models, while p509 (GAD509-528)- or p530 (GAD530-543)-expanded CD4(+)CD25(+) T cells had no such effects. Using computer-guided molecular modeling and docking methods, the differences in structural characteristics of these epitopes and the interaction mode (including binding energy and identified domains in the epitopes) between the above-mentioned epitopes and MHC class II I-A(g7) were analyzed. The theoretical results showed that the epitope p524, which induced protective Tregs, possessed negative surface-electrostatic potential and bound two chains of MHC class II I-A(g7), while the epitopes p509 and p530 which had no such ability exhibited positive surface-electrostatic potential and bound one chain of I-A(g7). Furthermore, p524 bound to I-A(g7) more stably than p509 and p530. Of importance, we hypothesized and subsequently confirmed experimentally that the epitope (GAD570-585, p570), which displayed similar characteristics to p524, was a protective epitope by showing that p570-expanded CD4(+)CD25(+) T cells suppressed the onset of diabetes in NOD mice. CONCLUSIONS/SIGNIFICANCE:These data suggest that molecular modeling-based structural analysis of epitopes may be an instrumental tool for prediction of protective epitopes to expand functional Tregs

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Endoscopic Decompression, Detorsion, and Reduction of Sigmoid Volvulus

Background: Colonic volvulus is a loop of bowel twisted around the site of mesenteric attachment leading to bowel obstruction. The sigmoid colon is involved in a majority of these cases. If untreated, sigmoid volvulus leads to bowel ischemia, perforation, sepsis, and potential death. Patients and methods: In this video manuscript, we present two patients with uncomplicated sigmoid volvulus that were successfully managed by emergent endoscopic decompression, detorsion, and reduction (EDDR) and temporary colon decompression tube placement as a bridge therapy to elective and definitive surgical interventions. Detailed endoscopic evaluation and techniques are described. In addition, classic radiological findings such as the “coffee bean” sign on plain radiograph and the “whirl” sign on computed tomography are shown. Results: After successful EDDR with subsequent bowel preparation and medical resuscitation, both patients underwent elective surgical resection of the sigmoid colon with primary anastomosis without post-operative complications. Conclusions: Sigmoid volvulus is a medical emergency and diagnosis requires a high index of suspicion. Emergent EDDR and decompression tube placement should be utilized as a first line treatment for patients with uncomplicated sigmoid volvulus. Keywords: Sigmoid volvulus, Endoscopy, Endoscopic decompression, detorsion and reduction (EDDR), Endoscopic decompression, Endoscopic reduction, Vide

Ilececum: A Comprehensive Review

For gastrointestinal endoscopists, the ileocecum is the finishing line during colonoscopy and it is identified by three endoscopic landmarks: terminal ileum, ileocecal valve, and the appendiceal orifice. Although ileal intubation is recommended during routine screening colonoscopy, it is not required in most cases of screening colonoscopy. Ileal intubation is indicated in certain circumstances such as suspected inflammatory bowel disease and GI bleeding. There is much pathology that can be observed within the ileocecum. Careful and systematic examination should be stressed during GI endoscopic training and practice. In this review, the authors demonstrate its anatomy, endoscopic findings, and pathologies