Search

Objective: To summarize the clinical characteristics and prognosis of febrile infection-related epilepsy syndrome with claustrum lesions (FIRES-C). Method: Clinical data of FIRES-C patients were collected retrospectively. The study reviewed and analyzed their clinical manifestations, treatment strategies, and prognosis. Result: Twenty patients were enrolled, including 13 females and 7 males, with a median onset age of 20.5 years. All patients developed seizures after fever, with a median interval of 5 days. Brain MRI showed symmetric lesions in the claustrum in all patients. The median interval from seizure onset to abnormal MRI signals detection was 12.5 days. All patients had negative results for comprehensive tests of neurotropic viruses and antineuronal autoantibodies. Seventy percent of cases had been previously empirically diagnosed with autoimmune encephalitis or viral encephalitis before. All patients received anti-seizure medicine. Eleven patients (55%) received antiviral therapy. All patients received immunotherapy, including glucocorticoids (100%), intravenous immunoglobulin (IVIg) (65%), plasma exchange (PLEX) (10%), tocilizumab (10%), rituximab (5%), and cyclophosphamide (5%). Sixty percent of patients received long-term immunotherapy (≥ 3 months). The median follow-up was 11.5 months;60% of patients were diagnosed with refractory epilepsy. Conclusion: Bilateral claustrum lesion on MRI is a distinctive neuroimage feature for FIRES, which may serve as an indication for the initial clinical assessments. FIRES-C should be classified as a type of inflammatory encephalopathy characterized by a monophasic nature. Some FIRES-C patients respond to immunotherapy and antiseizure treatments but most experience refractory epilepsy as a long-term outcome. [ABSTRACT FROM AUTHOR]

Groundwater storage (GWS) in confined aquifer systems is often influenced by climate variability and anthropogenic activities, and it is vital to quantify their contributions for the purpose of groundwater management and surface water allocation plans. In this study, we characterize the spatiotemporal evolution of the GWS in confined aquifer systems across Hengshui, North China Plain, and investigate its relationships with changing climate conditions and human activities through the integration of InSAR-derived surface displacements with hydraulic head observations and precipitation data, during 2004–2010 and 2016–2020. Our results indicate that the GWS in confined aquifer systems decreased markedly by 4.59 ± 0.35 km3 with an accelerating trend during the study period. The GWS variations show a strong correlation with precipitation during irrigation periods (March to July), and hence, the climate and anthropogenic-driven GWS variations can be separated from each other with a linear model. We find that the GWS depletion caused by climate variability and anthropogenic activities were −0.31 ± 0.10 km3 and −4.28 ± 0.40 km3, respectively, during the study period. The mean contribution of anthropogenic activities to the GWS variations was −71.9%, implying that the GWS variations in confined aquifer systems were primarily anthropogenic driven. It is also found that the well observations alone poorly characterize the spatiotemporal evolution of the GWS due to their limited spatial density, and the integrated InSAR/well approach appears to be promising for overcoming this challenge. [ABSTRACT FROM AUTHOR]

A supersonic multiphase flow was coupled with a ground simulation supersonic ablation test system to evaluate internal flow-field ablation/erosion performances of three-dimensional four-way braided carbon/carbon (C/C) composites. The results showed that the C/C composite mass and linear ablation rates were 0.0123 g/s and 0.0106 mm/s, respectively, in the supersonic inner flow-field ablation environment wherein kerosene and oxygen were completely burned. The overall material ablation was dominated by mechanical ablation accompanied by some C/CO 2 and C/H 2 O thermal oxidation ablations. With increasing oxygen enrichment, the composite mass and line ablation rates considerably increased to 0.0158 g/s and 0.0161 mm/s, respectively, in the 10%-oxygen-enriched internal flow-field ablation environment. And the composite thermal oxidation ablation was dominated by C/O 2 and supplemented by C/CO 2 and C/H 2 O reactions accompanied by rapid-airflow-induced mechanical erosion. In addition, the condensed-phase particle-induced erosion considerably reduced the C/C composite ablation resistance in the supersonic internal flow-field ablation environment. [ABSTRACT FROM AUTHOR]

Objective: To review the preparation, characteristics and research progress of different PsA animal models. Methods: Computerized searches were conducted in CNKI, PubMed and other databases to classify and discuss the relevant studies on PsA animal models. The search keywords were "PsA and animal model(s), PsA and animal(s), PsA and mouse, PsA and mice, PsA and rat(s), PsA and rabbit(s), PsA and dog(s)" Results: The experimental animals currently used to study PsA are mainly rodents, including mice and rats. According to the different methods of preparing the models, the retrieved animal models were classified into spontaneous or genetic mutation, transgenic and induced animal models. These PsA animal models involve multiple pathogenesis, some experimental animals' lesions appear in a short and comprehensive cycle, some have a high success rate in molding, and some are complex and less reproducibility. This article summarizes the preparation methods, advantages and disadvantages of different models. Conclusions: The animal models of PsA aim to mimic the clinicopathological alterations of PsA patients through gene mutation, transgenesis or targeted proinflammatory factor and to reveal new pathogenic pathways and therapeutic targets by exploring the pathological features and clinical manifestations of the disease. This work will have very far-reaching implications for the in-depth understanding of PsA and the development of new drugs. [ABSTRACT FROM AUTHOR]

Background: Impaired microcirculation in acute coronary syndrome (ACS) patients manifests inadequate recovery and adverse clinical outcome. Here, we analyzed correlations between peripheral microcirculation and heart function in ACS patients. Methods: Opisthenar microvessel area (OMA) were measured with optical coherence tomography angiography (OCTA), cardiac functional indexes (echocardiograph) were assessed 48–72 h after therapeutic interventions. Results: Results showed that OMA normalized with heart rate (OMA‐HR) were significantly greater in ACS patients with percutaneous intervention (ACS‐PCI, n = 25, stenosis >80%) compared to those with pharmacological intervention (ACS‐PI, n = 23, stenosis <50%, p =.02). Ejection fraction (EF) and fractional shortening (FS), which were not different between two groups, showed negative correlations with OMA‐HR in ACS‐PCI (EF: r = −0.512, p =.009; FS: r = −0.594, p =.002). Cardiac output (CO) inversely correlated with OMA‐HR in both groups (r = −0.697, p <.0001; r = −0.527, p =.01). Neutrophil to lymphocyte ratio (NLR) on admission was greater in ACS‐PCI group. NLR, which was negatively associated with EF or FS, was positively associated with OMA‐HR in all patients. The area under the curve (AUC) for OMA‐HR was 0.683 (specificity 0.696 and sensitivity 0.72, p =.02). OMA‐HR at >376.5 μm2 predicts reduced FS and CO (p =.002, p =.005, respectively). Summary OMA‐HR predicts inadequate recovery of the heart in severe ACS patients post‐PCI. [ABSTRACT FROM AUTHOR]

Background: In the current study, seizure semiology and potential predictive factors of seizure outcomes in glutamic acid decarboxylase antibody (GAD Ab)-associated neurological syndrome were investigated. Methods: In this study, 32 Chinese patients with GAD Ab-associated neurological syndrome who presented with seizures at Peking Union Medical College Hospital from January 2017 to October 2022 were reviewed; 30 had a follow-up duration of more than 1 year. Results: Among the 32 patients, 10 presented with epilepsy alone. Concomitant neurological syndromes were observed in 22 patients, including limbic encephalitis (n = 20), stiff-person syndrome (SPS, n = 1), and cerebellar ataxia (n = 1). Bilateral tonic–clonic seizures were observed in 21 patients (65.6%). Focal seizures occurred in 27 patients (84.4%); 17 had focal motor seizures and 18 focal non-motor seizures. Among 30 patients with long-term follow-up, 11 (36.7%) were seizure-free. Acute/subacute onset (p = 0.049) and comorbidity of limbic encephalitis with epilepsy (p = 0.023) led to better seizure outcomes. Patients with persistent epilepsy were more likely to have focal seizure (p = 0.003) and higher frequency of seizure (p = 0.001). Furthermore, these patients tended to have longer intervals from onset to immunomodulatory treatments. Early immunotherapy (within 6 months from onset) was administered in 81.8% of seizure-free patients but only in 42.1% of patients with persistent seizures. However, steroid and immunosuppressant duration did not differ in the two groups. Repeated serum GAD Ab tests during the follow-up showed no association with seizure outcomes. Conclusions: The seizure manifestations are diverse and variable. Approximately one third of patients achieved seizure remission during long-term follow-up. The type and frequency of seizures may influence the seizure outcomes. Early immunotherapy, especially within 6 months, may lead to better seizure outcomes. [ABSTRACT FROM AUTHOR]

Exposure of humans to aflatoxin B1 (AFB1) via ingestion of contaminated agricultural products is a major concern for human health throughout the world because epoxidized AFB1, biotransformed from AFB1 by hepatic CYP3A4, is strongly hepatotoxic and hepatocarcinogenic. Intestinal epithelial cells serve as a physical and physiological barrier against xenobiotics via their intercellular tight junction (TJ) seals and the metabolizing enzyme CYP3A4. However, the effect of AFB1 on the intestinal barrier remains unclear. Here, we investigated the influence of AFB1 on these physical and physiological intestinal barriers by means of an in vitro human intestinal model utilizing doxycycline-inducible CYP3A4-expressing Caco-2 cells, in which CYP3A4 activity is comparable to that in the adult human intestine. Cellular toxicity of AFB1 in induced Caco-2 cells (i.e., cells in which expression of CYP3A4 is induced by doxycycline) was approximately 5 times that of uninduced Caco-2 cells. Exposure to 16 µM AFB1 did not decrease the transepithelial electric resistance (TEER; a measure of TJ barrier integrity) in monolayers of uninduced Caco-2 cells to 95.8 % of that in vehicle-treated cells; in contrast, in induced Caco-2 cells, TEER was reduced to 28.8 %. Exposure to 16 µM AFB1 increased paracellular permeation of 4- and 20-kDa dextrans (paracellular permeation markers) through monolayers of induced Caco-2 cells to 5.4 and 5.2 times that through uninduced Caco-2 cells. These results together show that ingested AFB1 can modulate the intestinal barrier, and that inducible CYP3A4-expressing Caco-2 cells are a promising tool for evaluating the safety of food contaminants in the human intestine. • Aflatoxin B1 decreased tight junction-integrity in CYP3A4-Caco-2 cells. • Aflatoxin B1 enhanced paracellular permeation of macromolecules in CYP3A4-Caco-2 cells. • Intestinal CY3A4 may be a risk factor for disruption of intestinal barrier by aflatoxin B1. • The CYP3A4-Caco-2 cells are a promising in vitro model of the human intestine. [ABSTRACT FROM AUTHOR]

The transplantation of bone marrow-derived mesenchymal stem cells (BMMSCs) alleviates neuropathology and improves cognitive deficits in animal models with Alzheimer's disease. However, the underlying mechanism remains undefined. Based on meta-analysis and comprehensive review, high-profile studies support the theory that transplanted BMMSCs activate autophagy, as evidenced by the expression levels of signal molecules such as Beclin-1, Atg5, LC3-II, and mTOR. Functional autophagy mitigates neuronal apoptosis, which is reflected by the alterations of IAPs, Bcl-2, caspase-3, and so forth. Moreover, the transplantation of BMMSCs can decrease aberrant amyloid-beta peptides as well as tau aggregates, inhibit neuroinflammation, and stimulate synaptogenesis. There is a signal crosstalk between autophagy and apoptosis, which may be regulated to produce synergistic effect on the preconditioning of stem cells. Forasmuch, the therapeutic effect of transplanted BMMSCs can be enhanced by autophagy and/or apoptosis modulators. [ABSTRACT FROM AUTHOR]

As a ubiquitous toxic heavy metal, lead (Pb) exposure is known to be implicated in the onset and development of neurodegenerative diseases which may cause more serious health hazards with age and the accumulation of Pb in the body. Autophagy is the main degradation route for abnormal aggregated proteins and damaged cell organelles. Here, we aimed to study the effects of adolescent Pb exposure on autophagy at different life nodes. In this study, we developed a time-series model of Pb exposure in mice and randomly divided 4-week-old male C57BL/6 mice into six groups (4 C, 13 C, 16 C, 4Pb, 13Pb and 16Pb). Mice in Pb groups was consumed deionized water containing 0.2 % Pb(Ac) 2 for 3 months and then reared to anticipated life nodes, while the control group consumed deionized water. Western blot and Real-time qPCR were used to assess the effects of developmental Pb exposure on individual components of the autophagy machinery and modulation of microtubule-associated protein 1 light chain 3 (LC3) at each age stage. Our results showed that Pb exposure during adolescence reduced the p-mTOR/mTOR ratios with enhanced expression of Beclin-1, Atg12 and Atg7in both the hippocampus (HPC) and prefrontal cortex (PFC) of senescent mice while upregulation of LC3II/LC3I ratios and p62 suggested that autophagy mediates degradation was interrupted. Overall, we confirm that Pb exposure during adolescence promotes autophagic processes in the aged mice brain and that autophagic degradation is hindered, ultimately leading to a failure of autophagic degradation. • Prepubertal lead (Pb) exposure lead to failed autophagy in the aging mice. • Age-varying profiles of autophagic processes were manipulate by Pb exposure. • Pb exposure decreased the p-mTOR/mTOR ratio and upregulated the LC3II/LC3I ratio. [ABSTRACT FROM AUTHOR]

Long-term overexploitation of groundwater has led to significant land subsidence and ground fissures in the Xingtai plain. These geo-hazards have threatened the safety of buildings and infrastructures. It is extremely important to investigate the coupling relationship between land deformation and hydraulic head change for controlling land subsidence and mitigating ground fissures. In this study, we obtained the spatial and temporal evolution of land deformation in the Xingtai plain by using Envisat/ASAR data during 2009~2010 and Sentinel-1A data during 2015~2021. Combining InSAR results, head observations and geological data, we investigated the response of land deformation to head change and estimate the aquifer parameters. First, joint analysis of displacement time series and head changes infers that land subsidence was mainly caused by the inelastic compaction in acquitards. Compared with the subsidence patterns during 2009~2010, both the rate and spatial extent of land subsidence increased obviously during 2015~2021. Second, seasonal fluctuations in hydraulic head resulted in significant seasonal deformation with an amplitude of 10~30 mm and peak time of January~March, of which the spatial–temporal distribution was consistent with that of the rapid subsidence. Third, obvious differences in the deformation rate and seasonal amplitude were observed across the Longyao ground fissures and other three potential fissures during 2015~2021, suggesting that the activity of ground fissures increased compared with that during 2009~2010. Finally, using InSAR results and head observations, we estimated the elastic and inelastic skeletal storativity, with values ranging from 0.9 × 10−3 to 12.4 × 10−3 and 6.2 × 10−3 to 88.0 × 10−3, respectively. The comparison between elastic and inelastic skeletal storativity suggests that ~84.5% of total subsidence was irreversible and permanent. [ABSTRACT FROM AUTHOR]

Background and aims: To compare the value of three commonly used cardiovascular short-term risk scoring models, the GRACE score, TIMI score, and HEART score, in predicting the long-term prognosis of patients with acute myocardial infarction. Methods: The hospitalization data of patients who were hospitalized in West China Hospital of Sichuan University from 2011 to 2013 and diagnosed with acute myocardial infarction (AMI) were collected. The patients were scored by GRACE score, TIMI score, and HEART score. The long-term follow-up of patients was conducted until the end of January 2021. All-cause death and time of death of patients were confirmed by telephone follow-up, electronic medical record query, and household registration information. The predictive ability of different risk scores for long-term prognosis was compared according to the receiver operating characteristic (ROC) area under the curve (AUC), and the ability to distinguish patients with different risk levels was compared according to Kaplan–Meier survival curves. Results: The study ultimately included 2220 patients, with a median follow-up of 8 years and 454 (20.5%) deaths until the end of follow-up. Whether in ST-segment elevation myocardial infarction (STEMI) patients or non-ST-segment elevation myocardial infarction (NSTEMI) patients, the AUC value of the GRACE score (both AUC = 0.734) was significantly higher than the TIMI score (AUC = 0.675, p < 0.01; AUC = 0.665, p < 0.01) and HEART score (AUC = 0.632, p < 0.01; AUC = 0.611, p < 0.01) until the end of follow-up. In terms of risk stratification, the Kaplan–Meier survival curve shows that both THE GRACE score and TIMI score can distinguish AMI patients with different risk levels (p < 0.01), but the risk stratification ability of the HEART score in AMI patients was poor (p > 0.05). Conclusion: The GRACE risk score could represent a more accurate model to assess long-term death of acute myocardial infarction, but further studies are required. [ABSTRACT FROM AUTHOR]

In this study, C/C–SiC and C/C–SiC–ZrC composites were prepared via chemical vapor infiltration and polymer infiltration pyrolysis, and the ablation mechanism under hypersonic oxygen-rich environmental conditions was investigated. The C/C–SiC composites demonstrate an excellent ablation resistance in a hypersonic oxygen-rich environment with a relatively low temperature and speed of approximately 1800 K and 1100 m/s, respectively. It is only in the ablation center area with higher temperatures that a certain degree of thermochemical ablation was observed. The mass and linear ablation rates of C/C–SiC composites (0.027 g/s and 0.117 mm/s, respectively) showed a significant increase in a hypersonic oxygen-rich environment with a temperature and velocity of approximately 2050 K and 2000 m/s, respectively. The high-temperature ablation resistance of ZrC-modified C/C–SiC–ZrC composites improved significantly. However, the ZrC ceramic component had a considerable impact on the ablation resistance of the material. The structural integrity of C/C–20SiC–30ZrC composites was relatively high in hypersonic oxygen-rich environments with a jet temperature and velocity of 2050 K and 2000 m/s, respectively, and mass and linear ablation rates were 0.012 g/s and 0.015 mm/s, respectively. When the ZrC content increased by 40%, the ablation resistance of the composite reduced significantly, whereas the mass and linear ablation rates increased to 0.043 g/s and 0.130 mm/s, respectively. [ABSTRACT FROM AUTHOR]

We study the problem of simultaneous search for multiple targets over a multidimensional unit cube and derive fundamental resolution limits of non-adaptive querying procedures using the 20 questions estimation framework. The performance criterion that we consider is the achievable resolution, which is defined as the maximal $L_\infty $ norm between the location vector and its estimated version where the maximization is over all target location vectors. The fundamental resolution limit is defined as the minimal achievable resolution of any non-adaptive query procedure, where each query has binary yes/no answers. We drive non-asymptotic and second-order asymptotic bounds on the minimal achievable resolution, using tools from finite blocklength information theory. Specifically, in the achievability part, we relate the 20 questions problem to data transmission over a multiple access channel, use the information spectrum method by Han and borrow results from finite blocklength analysis for random access channel coding. In the converse part, we relate the 20 questions problem to data transmission over a point-to-point channel and adapt finite blocklength converse results for channel coding. Our results extend the purely first-order asymptotic analyses of Kaspi et al. (ISIT 2015) for the one-dimensional case: we consider channels beyond the binary symmetric channel and derive non-asymptotic and second-order asymptotic bounds on the performance of optimal non-adaptive query procedures. [ABSTRACT FROM AUTHOR]

• The SLM fabricated TC4 alloy after heat treatment and hot isostatic pressing consisted of α, β and a few VAl 10. • The HIP sample exhibited further refined basket-weave microstructure with uniform stress distribution. • The HIP sample exhibited a high stable value of 688.1 MPa for the fatigue strength at 107 cycles. • Three distinct regions of fatigue crack source, crack expansion zone and transient fracture zone were detected. SLM plays a critical role in in-space intelligent manufacturing and defense industries, while inherent hurdles due to internal defects in the SLM parts restrict practical reliability. Post-processing of heat treatment and hot isostatic pressing was comparatively applied to reveal the microstructure and fatigue performance. In this work, the resulted microstructure was revealed by XRD, SEM and TEM. Also, the stress-life curve of high cycle fatigue performance was obtained. This work provides a direct comparison for two post-processing techniques, contributing to more reliable application for SLM Ti alloy industrialization. [ABSTRACT FROM AUTHOR]

Microcystins (MCs) have a significant influence on aquatic ecosystems, but little is known about their terrestrial fate and impact. Here, we investigated the fate of two MCs (MC-LR and MC-RR) in the soil-earthworm system, with consideration of their congener-specific impact on earthworm health, soil bacteria, and soil metabolome. Although MCs had little acute lethal effect on earthworms, they caused obvious growth inhibition and setae rupture. Relative to MC-RR, MC-LR exhibited higher bioaccumulation and the resulting dermal lesions and deformation of longitudinal muscles. While the incorporation of both MCs into soils stimulated pathogenic bacteria and depressed oxidative stress tolerant bacteria, the response among soil nitrification and glutathione metabolism differed between the two congeners. The dissipation kinetics of MCs obeyed the first-order model. Earthworms stimulated soil N-cycling enzyme activities, increased the abundance of MC-degrading bacteria, and promoted bacterial metabolic functions related to glutathione metabolism, xenobiotics biodegradation, and metabolism of amino acids that comprise MCs, which accelerated the dissipation of MC-LR and MC-RR by 227% and 82%, respectively. These results provide evidence of significant congener differences in the terrestrial fate and impact of MCs, which will enable a better understanding of their role in mediating soil functions and ecosystem services. [Display omitted] • Microcystins have a congener-specific fate and impact in soil-earthworm systems. • Environmental levels of MCs are unlikely to have acute lethal effects on E. fetida. • Response in soil nitrification and GSH metabolism differs between the two MCs. • E. fetida promotes the microbial degradation of MCs in soil, especially for MC-LR. [ABSTRACT FROM AUTHOR]

Background: Tanshinone IIA (TSA), a major lipophilic component extracted from the roots of Salvia miltiorrhiza Bunge, has been widely used in China for its various biological activities. However, its effect on ovarian reserve in aged mice was not studied elsewhere. Objectives: This study aimed to explore the effect of TSA on the ovarian reserve of aged mice as well as young mice. Forty weeks old mice (N = 40) were considered as aged group compared to 4 weeks old mice (N = 40), and these groups were subdivided into four subgroups (N = 10) to receive different doses of TSA (0, 10, 20, and 40 μg/g/day). Methods: The effect of TSA was evaluated by counting follicular number by histological examination. Basal serum levels of FSH, LH, E2, and anti‐Mullerian hormone (AMH) were measured by ELISA. Moreover, the expression levels of antioxidant genes (CAT, Nrf2, GPX1), gap junction (Cx37), ERK1/2, and Smad5 family gene were examined at both mRNA (qPCR) and protein levels (western blot). Results: Follicular number, level of AMH and E2, and the expression of CAT, Nrf2, and GPX1 genes increased significantly (p < 0.05) in aged mice administrated with medium (20 μg/g/day) and high (40 μg/g/day) doses of TSA, whereas FSH and LH levels were significantly low compared to low dose (10 μg/g/day) and control (0 μg/g/day) aged subgroups. However, we did not observe any effect of all doses of TSA on young mice. Conclusions: Administration of TSA with medium and high doses up‐regulates the expression of antioxidative genes, reduces the oxidative injury, increases levels of AMH, and E2 levels that are relatively comparable to those in young mice, and consequently results in a healthy oocyte development. [ABSTRACT FROM AUTHOR]

Lymphoma is a serious malignant tumor that contains more than 70 different types and seriously endangers the body's lymphatic system. The lymphatic system is the regulatory center of the immune system and is important in the immune response to foreign antigens and tumors. Studies showed that multiple genetic variants are associated with lymphoma but determining the pathogenic mechanisms remains a challenge. In the present study, we first applied the Gene Ontology (GO) and KEGG pathway enrichment analyses of lymphoma-associated and lymphoma-nonassociated genes. Next, the Boruta and max-relevance and min-redundancy feature selection methods were performed to filter and rank features. Then, features preselected and ranked using the incremental feature selection method were applied for the decision tree model to identify the best GO terms and KEGG pathways and extract classification rules. Results indicate that our predicted features, such as B-cell activation, negative regulation of protein processing, negative regulation of mast cell cytokine production, and natural killer cell-mediated cytotoxicity, are associated with the biological process of lymphoma, consistent with those of recent publications. This study provides a new perspective for future research on the molecular mechanisms of lymphoma. [ABSTRACT FROM AUTHOR]

A small-scale plasma ablation facility was employed to test the four-directional carbon/carbon (4D C/C) composites under high enthalpy multi-phase jet condition for ablation/erosion performance evaluation with the ablation flow field studied via computational fluid dynamics (CFD). The various ablation rates, ablation behavior and microstructure of the C/C specimens were investigated. The overall mass ablation rate was 0.05715 g·s−1 with 0.05550 mm·s−1and 0.01794 mm·s−1 axial linear ablation rate of inner and outer walls. In the radial direction, the linear ablation rates were 0.07794 and 0.00517 mm·s−1 for the inner and external diameter respectively. Ablation changes the inner wall of the annular specimen into an inverted horn shape, while the edge near the jet becomes rounded corners after the plasma procedure. The interface between the axial carbon rod and the matrix has visible ring fractures. Alumina particles are lodged in cracks and holes as a result of multiphase flow scouring. The regression rate of the composites can be considerably accelerated by particle erosion and the existence of inherent defects. The specimen ablation of top surface and inner wall is attributed to the coupling of the heterogeneous reaction and multiphase erosion. On the back wall of specimen, the regression is mainly caused by thermochemical ablation. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the effects of 1‐methylcyclopropene (1‐MCP) on ethanol fermentation of Nanguo pears during ripening. Pears were exposed to 1 µl/L 1‐MCP and stored at 20 ± 2°C. Our data indicated that postharvest application of 1‐MCP maintained flesh firmness and reduced ethylene production and respiration rate during storage compared with untreated fruits. 1‐MCP treatment delayed the second glucose peak during fruit ripening. The contents of pyruvate and acetyl‐CoA were generally reduced by 1‐MCP treatment, and at the same time, their peaks were delayed by it during storage compared with controls. The contents of citric acid (CA) and oxaloacetate (OA) were increased by 1‐MCP, whereas the contents of acetaldehyde and ethanol were reduced during the whole storage period compared with controls. Activities of alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC) were reduced by application of 1‐MCP during the early stage of storage, and the appearance of their peak activities was also delayed after treatment with 1‐MCP. These data showed that postharvest application of 1‐MCP could effectively delay the production of the "alcohol taste" of Nanguo pears during ripening. Practical applications: Nanguo pear is one of the most common cultivars that widely grow in northeast China. It is preferred by many consumers for its unique "alcohol taste", which is mainly produced through ethanol fermentation during ripening. Until now, the mechanisms for regulating ethanol fermentation in ripening Nanguo pears are still unclear. Our data indicated that postharvest application of the ethylene action inhibitor 1‐MCP could effectively delay the production of the "alcohol taste" of Nanguo pears during ripening. The data from this study can provide reference data for maintaining the quality of postharvest Nanguo pears. [ABSTRACT FROM AUTHOR]

In remote sensing scene classification (RSSC), features can be extracted with different spatial frequencies where high-frequency features usually represent detailed information and low-frequency features usually represent global structures. However, it is challenging to extract meaningful semantic information for RSSC tasks by just utilizing high- or low-frequency features. The spatial composition of remote sensing images (RSIs) is more complex than that of natural images, and the scales of objects vary significantly. In this article, a multiscale feature fusion covariance network (MF2CNet) with octave convolution (Oct Conv) is proposed, which can extract multifrequency and multiscale features from RSIs. First, the multifrequency feature extraction (MFE) module is used to obtain fine-grained frequency features by Oct Conv. Then, the features of different layers in MF2CNet are fused by the multiscale feature fusion (MF2) module. Finally, instead of using global average pooling (GAP), global covariance pooling (GCP) extracts high-order information from RSIs to capture richer statistics of deep features. In the proposed MF2CNet, the obtained multifrequency and multiscale features can effectively improve the performance of CNNs. Experimental results on four public RSI datasets show that MF2CNet has advantages in RSSC over current state-of-the-art methods. The source codes of this method can be found at https://github.com/liuqingxin-chd/MF2CNet. [ABSTRACT FROM AUTHOR]

The transplantation of bone marrow-derived mesenchymal stem cells (BMMSCs) alleviates neuropathology and improves cognitive deficits in animal models with Alzheimer's disease. However, the underlying mechanism remains undefined. Based on meta-analysis and comprehensive review, high-profile studies support the theory that transplanted BMMSCs activate autophagy, as evidenced by the expression levels of signal molecules such as Beclin-1, Atg5, LC3-II, and mTOR. Functional autophagy mitigates neuronal apoptosis, which is reflected by the alterations of IAPs, Bcl-2, caspase-3, and so forth. Moreover, the transplantation of BMMSCs can decrease aberrant amyloid-beta peptides as well as tau aggregates, inhibit neuroinflammation, and stimulate synaptogenesis. There is a signal crosstalk between autophagy and apoptosis, which may be regulated to produce synergistic effect on the preconditioning of stem cells. Forasmuch, the therapeutic effect of transplanted BMMSCs can be enhanced by autophagy and/or apoptosis modulators. [ABSTRACT FROM AUTHOR]

Quercetin is widely distributed in nature and abundant in the human diet, which exhibits diverse biological activities and potential medical benefits. However, there remains a lack of comprehensive understanding about its cellular targets, impeding its in-depth mechanistic studies and clinical applications. This study aimed to profile protein targets of quercetin at the proteome level. A label-free CETSA-MS proteomics technique was employed for target enrichment and identification. The R package Inflect was used for melting curve fitting and target selection. D3Pocket and LiBiSco tools were used for binding pocket prediction and binding pocket analysis. Western blotting, molecular docking, site-directed mutagenesis and pull-down assays were used for target verification and validation. We curated a library of direct binding targets of quercetin in cells. This library comprises 37 proteins that show increased thermal stability upon quercetin binding and 33 proteins that display decreased thermal stability. Through Western blotting, molecular docking, site-directed mutagenesis and pull-down assays, we validated CBR1 and GSK3A from the stabilized protein group and MAPK1 from the destabilized group as direct binding targets of quercetin. Moreover, we characterized the shared chemical properties of the binding pockets of quercetin with targets. Our findings deepen our understanding of the proteins pivotal to the bioactivity of quercetin and lay the groundwork for further exploration into its mechanisms of action and potential clinical applications. [Display omitted] • Identification of quercetin's cellular protein targets using CETSA-MS. • Creation of a curated library with 37 stabilized and 33 destabilized proteins. • Identification of CBR1, GSK3A, and MAPK1 as direct quercetin binding targets. • Revelation of shared chemical properties in quercetin-target binding pockets. [ABSTRACT FROM AUTHOR]

The transmembrane α‐helices of membrane proteins are in general highly hydrophobic, and they enter the lipid bilayer through a lateral gate in the Sec61 translocon. However, some transmembrane α‐helices are less hydrophobic and form membrane channels or substrate‐binding pockets. Insertion of these amphipathic transmembrane α‐helices into the membrane requires the specific membrane‐embedded insertase called the endoplasmic reticulum membrane complex (EMC), which is a multi‐subunit chaperone distinct from the GET insertase complex. Four recent cryo‐electron microscopy studies on the eukaryotic EMC have revealed their remarkable architectural conservation from yeast to humans; a general consensus on the substrate transmembrane helix‐binding pocket; and the evolutionary link to the prokaryotic insertases of the tail‐anchored membrane proteins. These structures provide a solid framework for future mechanistic investigation. [ABSTRACT FROM AUTHOR]

DNA modifications, represented by 5‐methylcytosine (5mC), 5‐hydroxymethylcytosine (5hmC), 5‐formylcytosine (5fC), and 5‐carboxylcytosine (5caC), play important roles in epigenetic regulation of biological processes. The specific recognition of DNA modifications by the transcriptional protein machinery is thought to be a potential mechanism for epigenetic‐driven gene regulation, and many modified DNA‐specific binding proteins have been uncovered. However, the panoramic view of the roles of DNA modification readers at the proteome level remains largely unclear. Here, a recently developed concatenated tandem array of consensus transcription factor (TF) response elements (catTFREs) approach is employed to profile the binding activity of TFs at DNA modifications. Modified DNA‐binding activity is quantified for 1039 TFs, representing 70% of the TFs in the human genome. Additionally, the modified DNA‐binding activity of 600 TFs is monitored during the mouse brain development from the embryo to the adult stages. Readers of these DNA modifications are predicted, and the hierarchical networks between the transcriptional protein machinery and modified DNA are described. It is further demonstrated that ZNF24 and ZSCAN21 are potential readers of 5fC‐modified DNA. This study provides a landscape of TF–DNA modification interactions that can be used to elucidate the epigenetic‐related transcriptional regulation mechanisms under physiological conditions. [ABSTRACT FROM AUTHOR]

• C/C-SiC composite material thermal performance and ablation characteristicsis investigated under two heat flux conditions, 3593.54 kW·m−2 and 5644.86 kW·m−2, followed by calibration and CFD results. • The material ablation rates and back temperature curve are obtained. • The post-test ablation surface is divided into three ablation regions for analysis, compared with virgin material, as well as cross section of specimen. A small-scale plasma ablation facility was employed to test the C/C-SiC composite material for investigating the thermal performance and ablation characteristics under two heat flux conditions, 3593.54 kW·m−2 and 5644.86 kW·m−2. The morphology of post-test specimens was analyzed with the ablation rates calculated. The average mass ablation rates of two group specimens were 0.01735 and 0.10620 g·s−1 respectively with average linear ablation rate of 0.00680 and 0.09407 mm·s−1. Specimen surface could be divided into three regions with typical layered structure characteristics. For the stagnation point ablation test, the structural deformation in the ablation surface area featured in vertical layering and lateral regionality, forming an ablation pit near the stagnation point. In the center region, sublimation occured primarily, accompanied by a serious jet scouring of the molten liquid phase, as well as a small amount of oxidation reaction; Jet erosion with thermal sublimation was the main factor for the mass loss in the transitional region; Thermochemical reactions were mainly carried out in the marginal region. The SiO 2 generated from the thermochemical reaction of the material filled the interspace well and prevented the thermochemical reaction from penetrating deeper through the crack. The protective layer in the molten state with high viscosity reduced the damage of the high-speed jet impact material. [ABSTRACT FROM AUTHOR]

An acoustic prism for asymmetric transmissions is proposed, designed, and fabricated by an anisotropic metamaterial composed of an array of controllable C‐shaped meta‐atoms. Due to the anisotropic configuration of the meta‐atom, the effective refractive index of the prism can be continuously tuned by rotating the meta‐atom. It is demonstrated that the transmitted wave direction of an incident acoustic wave from one direction can be controlled in real time, as the rotation angle of meta‐atom changes gradually. Meanwhile, the incident acoustic wave from the opposite direction will be blocked all the time. Furthermore, a wide range of transmitted angles can be obtained by reshaping the prism, which can work in a broadband (4400–5200 Hz). The results are verified through theoretical predictions, numerical simulations, and experimental measurements. The method can be extended to realize other kinds of tunable asymmetric transmissions of waves via anisotropic metamaterials with controllable meta‐atoms. [ABSTRACT FROM AUTHOR]

Acute coronary syndrome (ACS) is a serious cardiovascular disease. The ACS risk prediction model is of great significance during the hospitalisation of ACS patients. However, traditional machine learning methods are not effective in predicting risk events in the ACS treatment process because of sample imbalance and noise. In this letter, the multilayer perceptron (MLP) and ensemble method are combined and then ensemble‐MLPs are proposed, which has made two innovations: 1) increase the diversity of the base MLP classifier at the data level, structure level, and parameter level and 2) improve the ensemble performance by proposing a new ensemble method using f1‐score weighted average. Experiments have shown that the proposed method outperforms conventional ensemble MLP method and other traditional machine learning methods on the task of predicting risk events in the ACS treatment process. [ABSTRACT FROM AUTHOR]

We reported a chiral oxamide‐phosphine ligand (COAP−Ph)‐Pd‐catalyzed asymmetric [3+2] cycloaddition reaction between vinyl cyclopropane compounds derived from 1,3‐indanedione and 2‐vinylcyclopropane‐1,1‐dicarboxylates with cyclic sulfonyl 1‐azadienes. The corresponding reactions provided a series of enantiomerically active spiro cyclopentane‐indandione and cyclopentane structures bearing three consecutive stereogenic centers in good yields with good diastereo‐ and enantioselectivity. The COAP−Pd complex serves not only to promote generation of chiral π‐allyl‐palladium intermediates and induce the asymmetry of the reaction, but also depress the background reaction. [ABSTRACT FROM AUTHOR]

In recent years, the Internet of Things (IoT) has been extensively investigated as an enabling technology to support massive devices or sensors. With increasing demands of seamless connectivity of IoT, space information networks (SINs) are adopted to provide reliable communications for IoT devices at any time and anywhere. However, the conventional SIN suffers from different malicious attacks (e.g., jamming attack, eavesdropping attack) due to its highly exposed satellite-ground links with fixed spot beams. Those attacks may cause severe security problems to SINs. To overcome these drawbacks, in this article, a secure architecture is proposed as a promising strategy to improve the security of SINs, where relays are deployed together with hopped beams to relieve the jamming attack of the uplink and combat the eavesdropping attack of the downlink. In the proposed new structure, by utilizing spatial diversity, inter-satellite beam hopping is developed to build jamming-free uplink channels, while relay selection is carried out to form eavesdropping-free downlink channels. Meanwhile, relay deployment optimization is studied to maximize the system efficiency, and data aggregation is adopted to encrypt the data packets of IoT devices at relays. As a result, the security of SINs can be strongly improved in the existence of jamming and eavesdropping threats. Furthermore, future works for the secure SIN are also discussed. [ABSTRACT FROM AUTHOR]

• The GT-C glycosyltransferases are membrane-associated enzyme complexes that use dolichol-linked donor substrates. • Eukaryotic OST complexes mediate protein N -glycosylation. • The yeast Pmt1–Pmt2 complex catalyzes protein O -mannosylation. • The yeast Alg6 is involved in the synthesis of oligosaccharide donor substrates for OST. • The glycosyltransferases EmbA-C and AftD are involved in mycobacterial cell-wall synthesis. The structural folds of glycosyltransferases are categorized into three superfamilies: GT-A, GT-B, and GT-C. Few structures of GT-C fold existed in the Protein Data Bank prior to the recent advent of high-resolution cryo-EM, because the glycosyltransferases are large membrane proteins that are difficult to crystallize. The use of cryo-EM has resulted in the structures of several key GT-C glycosyltransferases. Here we summarize the latest structural features of and mechanistic insights into these membrane enzyme complexes. [ABSTRACT FROM AUTHOR]

The time-modulated array (TMA)-based space-division multiple access (SDMA) approach is studied and verified, including the performance analysis and experimental verification. It utilizes the multibeam characteristic of TMA to implement the SDMA. For the uplink, the main power of signals with different incident angles would be redistributed to different harmonic components after time modulation. In this case, it plays a key role in this system to determine the harmonic order, which is selected to detect the received signal. A novel harmonic selection method for the uplink TMA-based SDMA systems is proposed by maximizing the received signal power. Furthermore, a closed-form expression of the spectral efficiency is deduced to verify the advantage of the simple harmonic selection scheme. Numerical results show that the TMA-based SDMA system can significantly improve the spectral efficiency compared with traditional single radio frequency (RF) chain systems. Meanwhile, it does not increase the number of RF chains. An L-band eight-element TMA is fabricated and tested to validate the feasibility of the TMA-based SDMA method. [ABSTRACT FROM AUTHOR]

Four individual lactic acid bacteria strains (LABs), including Lactobacillus plantarum, Lactobacillus reuteri, Lactobacillus rhamnosus, and Pediococcus pentosaceus, were used for the fermentation of Kuqa apple juice (KAJ). This work investigated the effects of four individual LABs on physical and chemical and antioxidant properties of fermented KAJ. In addition, this study combined sensory evaluation to select one or two suitable strains for fermenting KAJ. The results showed that P. pentosaceus had the fastest speed for fermentation. The maximum SOD activity of L. plantarum reached 284.33 U/ml. The TPC of L. reuteri had a high value of 94.00 mg/L. The DPPH‐free radical scavenging activity of L. plantarum eventually reached 97.90%, while the sensory evaluation of P. pentosaceus was the best with a 94% of GM value, followed by L. plantarum. Moreover, the major organic acid in fermented KAJ was malic acid. In summary, different strains have different effects on the characteristics of fermented KAJ, but in general, P. pentosaceus and L. plantarum are the most capable for fermenting KAJ. Novelty impact statement: The work provided the first research about malolactic fermentation for apples in Kuqa County, Xinjiang Province, China, which provided a new type of preservation technology for Kuqa apples and solved the problem of local apple with short storage period but high production. In addition, this work obtained the two most suitable strains for fermentation of Kuqa apple juice. In summary, this result provided a theoretical basis for the fermentation of Kuqa apple juice and enhanced economic benefits for the Kuqa apple industry. [ABSTRACT FROM AUTHOR]

The dopamine (DA) system has long been involved in social hierarchies; however, the specific mechanisms have not been elucidated. The lateral septum (LS) is a limbic brain structure that regulates various emotional, motivational, and social behaviors. DA receptors are abundantly expressed in the LS, modulating its functions. In this study, we evaluated the functions of DA receptors within different subregions of the LS in social dominance using a confrontation tube test in male mice. The results showed that mice living in social groups formed linear dominance hierarchies after a few days of cohousing, and the subordinates showed increased anxiety. Fos expressions was elevated in the entire LS after a confrontation tube test in the subordinates. However, DA neurons were more activated in the dominates within the ventral tegmental area and the dorsal raphe nucleus. Quantitative real-time polymerase chain reaction results showed that D2 receptor (D2R) within the intermediate region of the LS (LSi) were elevated in the subordinate. In the following pharmacological studies, we found simultaneous D2R activation in the dominants and D2R inhibition in the subordinates switched the original dominant–subordinate relationship. The aforementioned results suggested that D2R within the LSi plays an important role in social dominance in male mice. These findings improve our understanding of the neural mechanisms underlying the social hierarchy, which is closely related to our social life and happiness. [Display omitted] • Male mice established a linear social rank after a few days of cohousing. • Enhanced neural activity in the LS were observed in the subordinates. • DA neurons in the VTA and DR were more activated in the dominates. • D2R in the intermediate region of the LS were elevated in the subordinates. • Pharmacological modulation of D2R in the LS switched the dominant–subordinate relationship. [ABSTRACT FROM AUTHOR]

The authors have proposed a dual‐band reconfigurable Fabry–Pérot (F‐P) cavity antenna with high gain and meanwhile small radar cross‐sections (RCSs) in wideband. Different from the traditional F‐P antennas, they used a dynamic metasurface reflective plane (DMRP) as the lower superstrate to realise reconfigurable functions and a digital coding metasurface as the upper superstrate to achieve wideband RCS reduction. To investigate the dual‐band reconfigurability, a wideband rectangular waveguide is used to feed the F‐P antenna. By varying the bias voltage applied to varactors embedded in the elements of DMRP, the reflection phase of DMRP is changed and the two operating frequencies can be tuned electronically. To realise RCS reduction, they adopted a meticulous arrangement of the coding elements on partially reflecting surface. The designed metasurface‐assisted F‐P antenna has good radiation performance with high gain, high aperture efficiency, and high radiation efficiency. In the experiments, a prototype was fabricated via printed circuit board technology, and measured results agree well with numerical simulations. The measured peak gain reaches 17.52 dBi and the maximum aperture efficiency is 56.97%. The two reconfigurable bandwidths cover 5.10–5.40 and 6.60–6.93 GHz, respectively; and 7 dB RCS reduction is achieved from 9.40 to 13.7 GHz for arbitrary polarisation [ABSTRACT FROM AUTHOR]

Rosanortriterpenes A–B (RTA and RTB), two nortriterpenoids, are characteristic constituents in the fruits of Rosa laevigata var. leiocapus. However, pharmacological studies on these compounds are still scarce. In the present study, we aim to investigate the anti-inflammatory mechanisms associated with the effects of RTA–B in RAW264.7 macrophages and LO2 cells by detecting cell viabilities, nitric oxide (NO) production, tumour necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) production. Simultaneously, the anti-inflammatory action mechanisms of these two compounds were illustrated through western blot assay. Besides, the antihepatic fibrosis activities of these compounds have also been explored. The results demonstrated that RTA and RTB inhibited the production of NO, TNF-α, and IL-6 and suppressed liver fibrosis. RTA and RTB treatment also greatly inhibited the activation of NF-kappaB (NF-κB) pathway. Our study confirmed the promising anti-inflammatory and anti-liver fibrosis actions of RTA–B, suggesting that they might be developed as alternative and promising drugs for the treatment of hepatic inflammatory and fibrotic diseases. [ABSTRACT FROM AUTHOR]

The essential role of cyclic guanosine monophosphate (cGMP) signaling in regulating the oocyte meiotic cell cycle has been established. However, control of the level of cGMP in ovarian follicles is unclear. The cGMP-hydrolyzing phosphodiesterases (PDEs) are important in regulating the cellular cGMP level. We used zebrafish as a model to study the role of a cGMP-hydrolyzing phosphodiesterase-9a (PDE9a) in meiotic maturation of oocytes. Three PDE9a coding genes (PDE9aa, PDE9ab, and PDE9ac) were identified in zebrafish. Both pde9aa and pde9ac are expressed in most adult tissues including the ovary, but pde9ab is only expressed in the ovary, kidney, pituitary, and brain. All three pde9as mRNA exhibited different expression profiles during folliculogenesis. All of them are highly expressed in the oocyte but not in the follicular cell. The expression of both pde9aa and pde9ab , but not pde9ac , in ovarian follicles increases during oocyte maturation either in natural ovulatory cycle or induced by administration of hCG in vivo. We overexpressed pde9aa by injection of capped pde9aa mRNA into the oocytes. The cGMP level was decreased, and oocyte maturation was stimulated. When the activity of PDE9a was blocked by a specific inhibitor, Bay736691, the oocyte maturation was also stimulated. The stimulatory effect could be blocked by a gap junction blocker. However, the spontaneous oocyte maturation of denuded oocytes was not largely affected after treatment with Bay736691. All of the mature oocytes obtained by either treatment of Bay736691 or injection of pde9aa mRNA, could be fertilized in vitro. These results demonstrate the dual roles of PDE9a in oocyte maturation. The basal level of PDE9a is responsible for maintaining the meiotic arrest, and the increased level of PDE9a induced by LH signaling is helpful for stimulating meiotic maturation by hydrolyzing cGMP in oocytes. • Three PDE9a coding genes (PDE9aa, PDE9ab and PDE9ac) were identified in zebrafish. • All PDE9a mRNA are highly expressed in the oocyte of zebrafish. • The expression of both pde9aa and pde9ab is increased in oocyte during oocyte maturation. • PDE9a has dual roles in regulating the meiotic maturation of zebrafish oocytes. [ABSTRACT FROM AUTHOR]

This study investigates the ablation resistance of C/C–SiC composites using the ground simulation internal flow‐field supersonic oxygen‐rich ablation test technology. The microstructure evolution and ablation mechanism of the composites in a supersonic oxygen‐rich environment were explored by examining the macroscopic and microscopic ablation morphologies of the composites before and after the test. The results demonstrate that C/C–SiC composites exhibit excellent ablation resistance, with mass and linear ablation rates of .46 × 10−2 g/s and .42 × 10−2 mm/s, respectively, after 120 s of ablation in a low gas temperature and high oxygen‐rich ablation thermal environment. As the gas temperature increases, the mass and linear ablation rates of C/C–SiC composites gradually increase, even though the oxygen enrichment within the gas components decreases. When the gas temperature reaches 2178–2491 K, the mass and linear ablation rates increase to 1.31 × 10−2 g/s and .84 × 10−2 mm/s, respectively. Furthermore, at high temperatures above 2650 K, the mass and linear ablation rates of the composites exhibit a geometric multiple increase, reaching 4.73 × 10−2 g/s and 1.89 × 10−2 mm/s, respectively. These findings indicate that the ablation resistance of C/C–SiC composites in the supersonic oxygen‐rich ablation environment is more sensitive to gas temperature than oxygen enrichment. The main factors contributing to the increased ablation rate of C/C–SiC composites in the supersonic oxygen‐rich ablation process include the formation of a glass SiO2 oxide film, transition to molten SiO2, erosion of molten SiO2, and high‐temperature sublimation of the SiC matrix. [ABSTRACT FROM AUTHOR]

The fungal plasma membrane H+-ATPase (Pma1) pumps protons out of the cell to maintain the transmembrane electrochemical gradient and membrane potential. As an essential P-type ATPase uniquely found in fungi and plants, Pma1 is an attractive antifungal drug target. Two recent Cryo-EM studies on Pma1 have revealed its hexameric architecture, autoinhibitory and activation mechanisms, and proton transport mechanism. These structures provide new perspectives for the development of antifungal drugs targeting Pma1. In this article, we review the history of Pma1 structure determination, the latest structural insights into Pma1, and drug discoveries targeting Pma1. [ABSTRACT FROM AUTHOR]

In this article, we investigate a class of modified Boussinesq equations, for which we provide first an alternate proof of local well-posedness in the space (Hs ∩ L∞) x (Hs ∩ L∞)(ℝ) (s ≥ 0) to the one obtained by Constantin and Molinet [7]. Secondly, we show that the associated flow map is not smooth when considered from Hs x Hs(ℝ) into Hs(ℝ) for s < 0, thus providing a threshold for the regularity needed to perform a Picard iteration for these equations. [ABSTRACT FROM AUTHOR]

In machine-type communications (MTC), contention-based random access is employed to support a number of MTC devices with a limited number of resource blocks (RBs). Since multiple active devices may transmit signals in the same RB or channel, the collision caused by the presence of multiple signals is inevitable and the detection of collision becomes important. Furthermore, if the arrival time and the number of multiple signals can be estimated, successive interference cancellation (SIC) can be employed in time domain to improve the throughput. In this paper, we focus on the estimation of round-trip delays (RTD) of multiple signals in non-orthogonal random access (NORA) based on the maximum likelihood (ML) criterion. Since the computational complexity of the ML approach is high, we propose a low-complexity approach based on variational inference, which is widely used in machine learning. We also show that the number of signals can be reliably estimated from the estimated RTDs. [ABSTRACT FROM AUTHOR]

MOF‐5‐derived porous carbon (MDPC) materials, MDPC‐600 and MDPC‐1000, were prepared by pyrolysis at 600 °C in nitrogen atmosphere prior to acid treatment and at 1000 °C in nitrogen atmosphere, respectively. The samples were characterized by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), X–MaxN energy spectrum, and transmission electron microscopy (TEM). The test results of MDPC‐1000 and MDPC‐600 show that both are microporous amorphous carbon with the 2.7 nm diameter pore size, indicating that the micropore of MOF‐5 is well preserved during pyrolysis. MDPC‐1000 and MDPC‐600 have specific surface areas of 1570.9 m2/g and 1029.5 m2/g, respectively. MDPC‐1000 and MDPC‐600 were loaded with Fe ions to prepare Fe(III)/MDPC composite materials, which were used as catalysts for phenol hydroxylation. The results show that Fe(III)/MDPC‐1000 has higher catalytic effect than Fe(III)/MDPC‐600. During one hour phenol hydroxylation at 80 °C with 3 wt.% Fe concentration and a mass ratio of catalyst to phenol of 0.053, Fe(III)/MDPC‐1000 provides maximum phenol conversion, dihydroxybenzene yield, and dihydroxybenzene selectivity of 61.4%, 54.3%, and 88.4%, respectively. [ABSTRACT FROM AUTHOR]

We propose a tunable acoustic metamaterial based on anisotropic elements. By changing the incident angle or rotating the unit cell, the refractive index can be tuned continuously. Such an acoustic metamaterial element can be used to design and fabricate tunable gradient-index lenses, such as fundamental functional lenses, convergent lens, divergent lens, and deflection lens. These functions can be switched in real time without changing the physical structure. A prototype of the acoustic lens is fabricated by using three-dimensional printing technology, and the regulatory mechanism is implemented to testify its versatility. Our finding opens an avenue for designing tunable acoustic metamaterials and is expected to have wide applications in acoustic devices. [ABSTRACT FROM AUTHOR]

The metal-organic framework MOF-5 was synthesized by self-assembling of Zn(NO3)2·7H2O and H2BDC using DMF as solvent by the direct precipitation method and loaded with Fe2+ by the equivalent loading method at room temperature to prepare Fe(II)/MOF-5 catalyst and the microstructure, phases, and pore size of which was characterized by IR, XRD, SEM, TEM, and BET. It was found that Fe(II)/MOF-5 had high specific surface and porosity like MOF-5 and uniform pore distribution, and the pore size is 1.2 nm. In order to study the catalytic activity and reaction conditions of Fe(II)/MOF-5, it was used to catalyze the hydroxylation reaction of phenol with hydrogen peroxide. The results showed that the dihydroxybenzene yield of 53.2% and the catechol selectivity of 98.6% were obtained at the Fe2+ content of 3 wt.%, the mass ratio of Fe(II)/MOF-5 to phenol of 0.053, the reaction temperature of 80°C, and the reaction time of 2 h. [ABSTRACT FROM AUTHOR]

A self-designed oxygen-kerosene ablation system was employed to research the ablation properties of silicone rubber-based insulation material under different oxygen-rich conditions, that is, 0%, 5.00%, 7.71%, 17.01%, and 18.50%. The morphology of posttest specimens was analyzed via a scanning electron microscope (SEM), and the ablation rates were calculated. Experimental results showed that when the particle concentration was a fixed value, the mass and the linear ablation rates increased first and then decreased with the rise of oxygen content; the maximum values were 0.572 g/s and 0.933 mm/s, respectively. Under high oxygen-rich conditions, the formation of silicone rubber restricted the further increase of the ablation rates, filling more gaps of the reaction layer with liquid silicone rubber. Meanwhile, the thickness of the liquid glass layer attached to the surface was increased, which acted as a buffer against the impacts and erosion of particles and retarded the consumption and recession of materials. Excess oxygen spread to the edge of the ablation pit and reacted. Finally, these led to the increase in diameter of the ablation pit and the decrease of two types of ablation rates. [ABSTRACT FROM AUTHOR]

Echinacea purpurea polysaccharide (EPP) was obtained by modern separation technology and sulfated EPP (sEPP) was prepared by sulfation modification. The immunological effects of EPP and sEPP were compared on chicken bone marrow-derived dendritic cells (chBM-DCs). The results showed that the surface marker expression of CD11c and CD80 was increased after chBM-DCs were cultured with three dosage of sEPP, especially in sEPP M group. Three dosage of sEPP, EPP L and LPS could significantly enhance the effects of chBM-DCs on the proliferation of allogenic mixed lymphocytes. After chBM-DCs treatment with EPP or sEPP in vitro, the levels of IL-2 of sEPP H and EPP M groups were significantly higher than those of LPS group (P < 0.05). All sEPP and EPP groups could enhance the level of IFN-γ and down-regulated the level of IL-4 and IL-10. Results indicated that both sEPP and EPP had immunoregulatory effects on chBM-DCs, sEPP possessed better immunoregulatory effects as compared with EPP. [ABSTRACT FROM AUTHOR]

The phenotypic changes of tubular epithelial cell are hallmark features of renal diseases caused by abnormal uric acid levels. We hereby intend to investigate whether PI3K/p‐Akt signaling plays a role in uric‐acid induced epithelial−mesenchymal transition process. The normal rat kidney cell line (NRK‐52E) was used as a proximal tubular cell model in this study. NRK‐52E cells were exposed to different concentrations of uric acid, or PI3K inhibitor LY294002, or both, respectively. The effects of uric acid on cell morphology were examined by phase contrast microscopy, while molecular alternations were assessed by western blot analysis and immunofluorescence staining. We found that uric acid induced visible morphological alterations in NRK‐52E cells accompanied by increased expression of α‐smooth muscle actin and reduced expression of E‐cadherin. Moreover, phosphorylation of Akt protein was obviously increased, whereas Akt level remained stable. Furthermore, the above effects were abolished when PI3K/p‐Akt pathway was blocked by the PI3K inhibitor. These findings demonstrated that high uric acid could induce phenotypic transition of cultured renal tubular cells, which was probably via activating PI3K/p‐Akt signaling pathway. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the accuracy of 18F-FDG-PET/CT for the detection of recurrent and/or metastatic diseases in differentiated thyroid cancer (DTC) patients with thyroglobulin elevation and negative iodine scintigraphy. Whether PET/CT with TSH stimulation (sPET/CT) had better diagnostic performance than PET/CT without TSH stimulation (nsPET/CT) in this scenario was also evaluated. Methods: PubMed and Embase databases were searched for eligible studies from January 2001 to December 2018. Only studies with clearly stated reference standard (histopathology confirmation and/or clinical/imaging follow-up) were included. Publication bias was assessed by Deeks funnel plot. The pooled sensitivity, specificity, diagnostic odds ratio (DOR) and the area under the summary receiver-operating characteristics curve (AUC) for PET/CT was determined by random-effect analysis, respectively. sPET/CT and nsPET/CT were compared pairwise for all diagnostic estimate indexes using Z-test. Results: We included 17 studies with 1195 patients in this meta-analysis. The pooled sensitivity, specificity, DOR and AUC for PET/CT on patient-based data were 0.86 (95% CI: 0.79–0.91), 0.84 (95% CI: 0.72–0.91), 31.00 (95% CI: 12.00–80.00) and 0.91 (95% CI: 0.88–0.93), respectively. There was high heterogeneity (I² = 80% for sensitivity, I² = 82% for specificity) and possible publication bias (P = 0.01). Z test did not detect statistically significant difference between sPET/CT and nsPET/CT for all the diagnostic estimate indexes (all P> 0.05). Conclusions: On patient-based analysis, 18F-FDG-PET/CT has high diagnostic accuracy for the detection of recurrent and/or metastatic diseases in DTC patients with thyroglobulin elevation and negative iodine scintigraphy, but existing studies were limited by high heterogeneity and possible publication bias. The diagnostic performance of sPET/CT may be not superior to nsPET/CT. [ABSTRACT FROM AUTHOR]