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71.
Two-dimensional (2D) tri-TMDCs carrier dynamics provide a platform for studying excitons through Ultrafast Pump-Probe Transient Absorption Spectroscopy. Here we studied the ZrTe3 nanosheets (NTs) exciton dynamics by transient absorption (TA) spectrometer. We observed different carrier dynamics in the ZrTe3 NTs sample at different pump powers and with many wavelengths in the transient absorption spectrometer. The shorter life decay constant is associated with electron-phonon relaxation. Similarly, the longer-life decay constant represents the long live process that is associated with charge separation. The interactions between carrier-phonons at nanoscale materials can be changed by phonons quantum confinements. The hot carrier lifetime determined the strength of carrier phonon interactions. The value of fast decay in the conduction band is due to carrier relaxation or the carrier gets trapped due to surface states or localized defects. The value of slow decay is due to the recombination of surface state and localized defects processes. The lifetime declines for long wavelengths as size decreases. Whereas, during short wavelength-independent decay, carrier characteristics have been observed. TA spectroscopy is employed to investigate insight information of the carrier’s dynamical processes such as carrier lifetime, cooling dynamics, carrier diffusion, and carrier excitations. The absorption enhanced along excitons density with the increase of pump power, which caused a greater number of carriers in the excited state than in the ground state. The TA signals consist of trap carriers and (electron-hole) constituents, which can be increased by TA changes that rely on photoexcitation and carrier properties.  相似文献   
72.
As graft survival in pediatric LT is often affected by progressive fibrosis, numerous centers carry out protocol liver biopsies. Follow‐up biopsy protocols differ from center to center, but all biopsies are progressively spaced out, as time from transplant increases. Therefore, there is a need for non‐invasive techniques to evaluate graft fibrosis progression in those children who have no clinical or serological signs of liver damage. Indirect markers, such as the APRI, should be relied on with caution because their sensitivity in predicting fibrosis can be strongly influenced by the etiology of liver disease, severity of fibrosis, and patient age. A valid alternative could be TE, a non‐invasive technique already validated in adults, which estimates the stiffness of the cylindrical volume of liver tissue, 100‐fold the size of a standard needle biopsy sample. The aims of this study were to evaluate the reliability of TE in children after LT and to compare both the TE and the APRI index results with the histological scores of fibrosis on liver biopsies. A total of 36 pediatric LT recipients were studied. All patients underwent both TE and biopsy within a year (median interval ‐0.012 months) at an interval from LT of 0.36 to 19.47 years (median 3.02 years). Fibrosis was assessed on the biopsy specimens at histology and staged according to METAVIR. There was a statistically significant correlation between TE stiffness values and METAVIR scores (P = .005). The diagnostic accuracy of TE for the diagnosis of significant fibrosis (F ≥ 2) was measured as the area under the curve (AUROC = 0.865), and it demonstrated that the method had a good diagnostic performance. APRI was not so accurate in assessing graft fibrosis when compared to METAVIR (AUROC = 0.592). A liver stiffness cutoff value of 5.6 kPa at TE was identified as the best predictor for a significant graft fibrosis (METAVIR F ≥ 2) on liver biopsy, with a 75% sensitivity, a 95.8% specificity, a 90% positive predictive value, and an 88.5% negative predictive value. These data suggest that TE may represent a non‐invasive, reliable tool for the assessment of graft fibrosis in the follow‐up of LT children, alerting the clinicians to the indication for a liver biopsy, with the aim of reducing the number of protocol liver biopsies.  相似文献   
73.
The immunohistochemical distribution of capsaicin/vanilloid (transient receptor potential vanilloid 1, TRPV1) receptors and neuropeptides (CGRP, SP) was studied in the gastrointestinal mucosal biopsies of patients with gastritis, erosions, ulcers, polyps, adenocarcinoma, chronic inflammatory bowel diseases, polyps without and with hyperplasia, dysplasia and adenocarcinoma in colon. The studies were carried out in 127 patients and 30 people with only functional dyspepsia (without any histological alteration). The results were: (1) the positivity of TRPV1 receptor and CGRP was detected, and weak participation of SP was detected in patients with different gastric diseases; (2) the presence of TRPV1, CGRP and SP could be detected in chronic inflammation of bowel disease; (3) SP could not detected in patients with colon polyps, dysplasia and adenocarcinoma; (4) the presence of TRPV1 and CGRP was proved in colon dysplasia and adenocarcinoma. We conclude that (1) the immunohistochemical distribution of TRPV1, CGRP and SP differs in gastrointestinal diseases of the upper and lower tract, and (2) the participation of TRPV1, CGRP and SP differs significantly in these different gastrointestinal diseases.  相似文献   
74.
75.
Understanding the laminar brain structure is of great help in further developing our knowledge of the functions of the brain. However, since most layer segmentation methods are invasive, it is difficult to apply them to the human brain in vivo. To systematically explore the human brain''s laminar structure noninvasively, the K‐means clustering algorithm was used to automatically segment the left hemisphere into two layers, the superficial and deep layers, using a 7 Tesla (T) diffusion magnetic resonance imaging (dMRI)open dataset. The obtained layer thickness was then compared with the layer thickness of the BigBrain reference dataset, which segmented the neocortex into six layers based on the von Economo atlas. The results show a significant correlation not only between our automatically segmented superficial layer thickness and the thickness of layers 1–3 from the reference histological data, but also between our automatically segmented deep layer thickness and the thickness of layers 4–6 from the reference histological data. Second, we constructed the laminar connections between two pairs of unidirectional connected regions, which is consistent with prior research. Finally, we conducted the laminar analysis of the working memory, which was challenging to do in the past, and explained the conclusions of the functional analysis. Our work successfully demonstrates that it is possible to segment the human cortex noninvasively into layers using dMRI data and further explores the mechanisms of the human brain.  相似文献   
76.
The fatigue assessment of tube connections under cyclic pressure is discussed using four kinds of methods from ASME VIII-2 and EN 13445-3. FEA results are compared to the fatigue test, and some conclusions are obtained. Method 1 is the most widely used traditional method and can be used in both welded structures and unwelded structures. This method has simple operation, safety and reliability. Method 2 adopts the effective strain range to assess the fatigue for both the welded and the unwelded structure. This method is with high accuracy, good stability, safety and reliability, but the elastic–plastic analysis is very complicated. Method 3 adopts the equivalent structure stress to assess the fatigue of the welded, it is developed from fracture mechanics, and the procedure is also very complicated. Method 4 is a detailed assessment procedure for the welded and unwelded, and it is the most accurate, stable and reliable among the four methods.  相似文献   
77.
We investigated the immediate and longer-term impact (over 4-6 months) of probable COVID-19 infection on mental health, wellbeing, financial hardship, and social interactions among older people living in England. Data were analysed from 5146 older adults participating in the English Longitudinal Study of Ageing who provided data before the pandemic (2018-19) and at two COVID-19 assessments in 2020 (June-July and November-December). The associations of probable COVID-19 infection (first COVID-19 assessment) with depression, anxiety, poor quality of life (QoL), loneliness, financial hardship, and social contact with family/friends at the first and second COVID-19 assessments were tested using linear/logistic regression and were adjusted for pre-pandemic outcome measures. Participants with probable infection had higher levels of depression and anxiety, poorer QoL, and greater loneliness scores compared with those without probable infection at both the first (ORdepression = 1.62, P-value = 0.005; ORanxiety = 1.59, P-value = 0.049; bpoorQoL = 1.34, P < 0.001; bloneliness = 0.49, P < 0.001) and second (ORdepression = 1.56, P-value = 0.003; ORanxiety = 1.55, P-value = 0.041; bpoorQoL = 1.38, P-value < 0.001; bloneliness = 0.31, P-value = 0.024) COVID-19 assessments. Participants with probable infection also experienced greater financial difficulties than those without infection at the first assessment (OR = 1.50, P-value = 0.011). Probable COVID-19 infection is associated with longer-term deterioration of mental health and wellbeing and short-term increases in financial hardship among older adults. It is important to monitor the mental health of older people affected by COVID-19 and provide additional support to those in need.

The coronavirus disease 2019 (COVID-19) pandemic has affected several aspects of people’s lives, including physical and mental health, employment and financial security, social connections, and access to healthcare (1). Despite a large body of research documenting the adverse psychosocial effects of the pandemic and its containment measures across the population, little is currently known regarding the impact that contracting COVID-19 itself may have on the individual’s mental health, personal finances, and social relationships.Several longitudinal studies have reported increases in depression, anxiety, and general psychological distress in the adult population during the COVID-19 pandemic compared with prepandemic levels (2, 3). People who have contracted COVID-19 might be particularly vulnerable to the psychological impact of the pandemic. Indeed, initial evidence suggests that the experience of COVID-19 symptoms is associated not only with adverse physical consequences, but also with long-term effects on mental health (4, 5). Various mechanisms could underlie the psychological effects of COVID-19 infection, including the potential neurotropic properties of the virus (6, 7); the presence of elevated proinflammatory cytokines (e.g., interleukin-6) in patients with severe COVID-19 symptoms (8), which are implicated in the development of psychiatric disorders such as depression (9); and the exposure to prolonged periods of social isolation and physical inactivity in people affected by COVID-19 (10), which in turn can increase mental distress and feelings of loneliness. Compounded by the widespread psychosocial effects of the pandemic across the population, these factors might further exacerbate the risk of mental health problems among individuals recovering from COVID-19 infection.Data from previous coronavirus epidemics demonstrate the potential psychiatric consequences of the virus in both the acute and postacute phases of the illness (11). Further, studies across different countries have found that individuals reporting COVID-19 symptoms and patients recovering from acute COVID-19 illness exhibit increased levels of anxiety, depression, suicidal ideation, loneliness, and poor quality of life (QoL) compared with healthy people (5, 1219). Studies using data from electronic health records in the United States have also shown that COVID-19 patients with no previous psychiatric history are at increased risk of first-time diagnosis of psychiatric disorders compared with those affected by other health events (e.g., influenza) or healthy controls (20, 21). However, most studies to date are limited by small, nonrepresentative samples and short follow-up periods, and they lack longitudinal data on the participants’ mental health before COVID-19, as well as data on confounding factors. Since individuals with preexisting mental disorders seem particularly susceptible to COVID-19 infection (20, 22), it is unclear the extent to which reverse causality and confounding bias might contribute to the association between COVID-19 infection and psychological distress. In addition, studies involving electronic health records or clinical samples may not capture individuals with moderate COVID-19 symptoms and those with less severe mental health problems who do not present to health services.Longitudinal cohort studies are well suited to study the immediate and longer-term psychosocial consequences of COVID-19 infection in the general population, as they include comprehensive information on mental health before the infection and other confounding factors (e.g., sex, age, socioeconomic position). Results from the United Kingdom suggest that people with probable COVID-19 symptoms experience greater psychological distress up to 7 months following the start of the infection (23). In contrast, an online study in the United States found evidence only for short-term psychological effects that diminish as the symptoms subside (24). Notably, these studies have only focused on general psychological distress; therefore, the impact of COVID-19 infection on specific mental health and wellbeing outcomes (e.g., depression, anxiety, loneliness, and QoL) in the general population is unclear.Numerous studies have also highlighted the financial impact of the pandemic—including job losses, pay cuts, reductions in household income, fluctuations in stock markets and wealth held in risky assets, and widespread financial worries (2527)—as well as its adverse consequences for various domains of social relationships, including social networks, social support, and social interaction (28, 29). However, these studies relate to the whole population rather than to people with COVID-19 infection. Empirical evidence regarding the impact that COVID-19 infection may have on a person’s financial situation and social relationships is limited. For instance, cross-sectional results suggest that adults who have experienced COVID-19 are more likely to report that their social relationships, work, and household finances have been adversely affected by the pandemic, compared with those who have not had COVID-19 (30). However, this analysis did not account for preexisting trends in social connections and economic outcomes, and it was unable to disentangle short-term versus longer-term psychosocial consequences of the infection.Older adults are at increased risk of social isolation and serious illness following COVID-19 infection (31), and they also are particularly vulnerable to the effects of chronic stress on the brain (32). A recent analysis of data from the English Longitudinal Study of Aging (ELSA) also demonstrates that the mental health and wellbeing of the older population deteriorated significantly as the pandemic progressed in 2020, compared with prepandemic levels (33). Given these factors, older people might be disproportionally affected by the psychosocial effects of COVID-19 infection. However, little research on COVID-19 has involved older adults who are also often unable to access online surveys (34). In addition, care-seeking behaviors changed considerably in the early stages of the pandemic, with large numbers of older adults with care needs not actively contacting health services and not seeking help (35). Therefore, older adults’ experiences of COVID-19 might be underrepresented in earlier studies.In the present analysis, we investigated the immediate and longer-term impact (over 4 to 6 months) of probable COVID-19 infection on mental health (i.e., depression and anxiety), wellbeing (i.e., QoL and loneliness), financial hardship, and social interactions in a large, representative sample of older adults from ELSA. In addition, we assessed whether the psychosocial impact of probable COVID-19 infection might vary across different sociodemographic groups. All outcomes were assessed before the pandemic began (i.e., 2018/2019) and on two occasions during the pandemic, which enabled us to test both short-term and longer-term associations. The data were collected online and by telephone interview to ensure coverage of those without internet access.  相似文献   
78.
目的 将神经干细胞(NSCs)移植和神经生长因子(NGF)单独及联合应用于大脑中动脉阻塞(MCAo)模型大鼠,观察NGF和NSCs移植对大鼠缺血性脑卒中神经功能恢复的作用及NGF对自体和移植NSCs的影响.方法 体外分离、培养新生大鼠海马NSCs,BrdU标记.实验动物随机分为A组(MCAo组)、B组(MCAo NGF组)、C组(MCAo NSCs组)及D组(MCAo NGF NSCs组),每组16只,移植后进行神经功能损害评分(NSS),用免疫组化行BrdU、槽蛋白检测,分析结果.结果 移植后的2周、4周神经功能评分显示D组显著好于其他3组(P<0.05),B组与C组显著好于A组(P<0.05).B组的槽蛋白及BrdU阳性细胞数最著多于A组(P<0.05),D组的BrdU阳性细胞数显著多于C组(P<0.05).结论 NSCs移植和NGF单独及联合应用对MCAo大鼠的神经功能恢复均有作用,二者联合具有协同作用.NGF对自体NSCs的激活、增殖有促进作用,对移植NSCs的增殖有促进作用.  相似文献   
79.
In patients with triple-negative breast cancer (TNBC), high tumour mutation burden and aberrant oncogene expression profiles are some of the causes of poor prognosis. Therefore, it is necessary to identify aberrantly expressed oncogenes, since they have the potential to serve as therapeutic targets. Transient receptor potential channel 5 opposite strand (TRPC5OS) has been previously shown to function as a novel tumour inducer. However, the underlying mechanism of TRPC5OS function in TNBC remain to be elucidated. Therefore, in the present study TRPC5OS expression was first measured in tissue samples of patients with TNBC and a panel of breast cancer cell lines (ZR-75-1, MDA-MB-453, SK-BR-3, JIMT-1, BT474 and HCC1937) by using qRT-PCR and Western blotting. Subsequently, the possible effects of TRPC5OS on MDA-MB-231 cells proliferation were determined using Cell Counting Kit-8 and 5-Ethynyl-2′-deoxyuridine assays after Lentiviral transfection of MDA-MB-231. In addition, potential interaction partners of TRPC5OS were explored using liquid chromatography-mass spectrometry (LC-MS)/MS. Gene expression patterns following TRPC5OS overexpression were also detected in MDA-MB-231 cells by using High-throughput sequencing. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis were then used to systematically verify the potential interactions among the TRPC5OS-regulated genes. The potential relationship between TRPC5OS-interacting proteins and gene expression patterns were studied using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) analysis. TRPC5OS expression was found to be significantly higher in TNBC tumour tissues and breast cancer cell lines compared with luminal tumour tissues and ZR-75-1. In addition, the overexpression of TRPC5OS significantly increased cell proliferation. High-throughput sequencing results revealed that 5,256 genes exhibited differential expression following TRPC5OS overexpression, including 3,269 upregulated genes and 1,987 downregulated genes. GO analysis results indicated that the functions of these differentially expressed genes were enriched in the categories of ‘cell division’ and ‘cell proliferation’ regulation. KEGG analysis showed that the TRPC5OS-regulated genes were associated with processes of ‘homologous recombination’ and ‘TNF signalling pathways’. Subsequently, 17 TRPC5OS-interacting proteins were found using LC-MS/MS and STRING analysis. The most important protein among interacting proteins was ENO1 which was associated with glycolysis and regulated proliferation of cancer. In summary, data from the present study suggest that TRPC5OS overexpression can increase TNBC cell proliferation and ENO1 may be a potential target protein mediated by TRPC5OS. Therefore, TRPC5OS may serve as a novel therapeutic target for TNBC.  相似文献   
80.
Deoxynivalenol (DON), the most naturally-occurring trichothecenes, may affect animal and human health by causing vomiting as a hallmark of food poisoning. Deoxynivalenol-3-glucoside (D3G) usually co-occurs with DON as its glucosylated form and is another emerging food safety issue in recent years. However, the toxicity of D3G is not fully understood compared to DON, especially in emetic potency. The goals of this research were to (1) compare emetic effects to D3G by oral and intraperitoneal (IP) routes and relate emetic effects to brain-gut peptides glucose-dependent insulinotropic polypeptide (GIP) and substance P (SP) in mink; (2) determine the roles of calcium-sensing receptor (CaSR) and transient receptor potential (TRP) channel in D3G’s emetic effect. Both oral and IP exposure to D3G elicited marked emetic events. This emetic response corresponded to an elevation of GIP and SP. Blocking the GIP receptor (GIPR) diminished emetic response induction by GIP and D3G. The neurokinin 1 receptor (NK-1R) inhibitor Emend® restrained the induction of emesis by SP and D3G. Importantly, CaSR antagonist NPS-2143 or TRP channel antagonist ruthenium red dose-dependently inhibited both D3G-induced emesis and brain-gut peptides GIP and SP release; cotreatment with both antagonists additively suppressed both emetic and brain-gut peptide responses to D3G. To summarize, our findings demonstrate that activation of CaSR and TRP channels contributes to D3G-induced emesis by mediating brain-gut peptide exocytosis in mink.  相似文献   
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