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Nutrient enrichment impacts grassland plant diversity such as species richness, functional trait composition and diversity, but whether and how these changes affect ecosystem stability in the face of increasing climate extremes remains largely unknown.We quantified the direct and diversity‐mediated effects of nutrient addition (by nitrogen, phosphorus, and potassium) on the stability of above‐ground biomass production in 10 long‐term grassland experimental sites. We measured five facets of stability as the temporal invariability, resistance during and recovery after extreme dry and wet growing seasons.Leaf traits (leaf carbon, nitrogen, phosphorus, potassium, and specific leaf area) were measured under ambient and nutrient addition conditions in the field and were used to construct the leaf economic spectrum (LES). We calculated functional trait composition and diversity of LES and of single leaf traits. We quantified the contribution of intraspecific trait shifts and species replacement to change in functional trait composition as responses to nutrient addition and its implications for ecosystem stability.Nutrient addition decreased functional trait diversity and drove grassland communities to the faster end of the LES primarily through intraspecific trait shifts, suggesting that intraspecific trait shifts should be included for accurately predicting ecosystem stability. Moreover, the change in functional trait diversity of the LES in turn influenced different facets of stability. That said, these diversity‐mediated effects were overall weak and/or overwhelmed by the direct effects of nutrient addition on stability. As a result, nutrient addition did not strongly impact any of the stability facets. These results were generally consistent using individual leaf traits but the dominant pathways differed. Importantly, major influencing pathways differed using average trait values extracted from global trait databases (e.g. TRY).Synthesis. Investigating changes in multiple facets of plant diversity and their impacts on multidimensional stability under global changes such as nutrient enrichment can improve our understanding of the processes and mechanisms maintaining ecosystem stability. [ABSTRACT FROM AUTHOR]

Background: Chronic heart failure (CHF) has always posed a significant threat to human survival and health. The efficacy of thiamine supplementation in CHF patients remains uncertain. Hypothesis: Receiving supplementary thiamine may not confer benefits to patients with CHF. Methods: A comprehensive search was conducted across the Cochrane Library, PubMed, EMBASE, ClinicalTrials.gov, and Web of Science databases up until May 2023 to identify articles investigating the effects of thiamine supplementation in CHF patients. Predefined criteria were utilized for selecting data on study characteristics and results. Results: Seven randomized, double‐blind, controlled trials (five parallel trials and two crossover trials) involving a total of 274 patients were enrolled. The results of the meta‐analysis pooling these studies did not reveal any significant effect of thiamine treatment compared with placebo on left ventricular ejection fraction (WMD = 1.653%, 95% CI: −1.098 to 4.405, p = 0.239, I2 = 61.8%), left ventricular end‐diastolic volume (WMD = −6.831 mL, 95% CI: −26.367 to 12.704, p = 0.493, I2 = 0.0%), 6‐min walking test (WMD = 16.526 m, 95% CI: −36.582 to 69.634, p = 0.542, I2 = 66.3%), N‐terminal pro‐B type natriuretic peptide (WMD = 258.150 pg/mL, 95% CI: −236.406 to 752.707, p = 0.306, I2 = 21.6%), or New York Heart Association class (WMD = −0.223, 95% CI: −0.781 to 0.335, p = 0.434, I2 = 87.1%). However, it effectively improved the status of thiamine deficiency (TD). Conclusions: Our meta‐analysis indicates that thiamine supplementation does not have a direct therapeutic effect on CHF, except for correcting TD. [ABSTRACT FROM AUTHOR]

Background: Vessels encapsulating tumor cluster (VETC) is a critical prognostic factor and therapeutic predictor of hepatocellular carcinoma (HCC). However, noninvasive evaluation of VETC remains challenging. Purpose: To develop and validate a deep learning radiomic (DLR) model of dynamic contrast‐enhanced MRI (DCE‐MRI) for the preoperative discrimination of VETC and prognosis of HCC. Study type: Retrospective. Population: A total of 221 patients with histologically confirmed HCC and stratified this cohort into training set (n = 154) and time‐independent validation set (n = 67). Field Strength/Sequence: A 1.5 T and 3.0 T; DCE imaging with T1‐weighted three‐dimensional fast spoiled gradient echo. Assessment: Histological specimens were used to evaluate VETC status. VETC+ cases had a visible pattern (≥5% tumor area), while cases without any pattern were VETC−. The regions of intratumor and peritumor were segmented manually in the arterial, portal‐venous and delayed phase (AP, PP, and DP, respectively) of DCE‐MRI and reproducibility of segmentation was evaluated. Deep neural network and machine learning (ML) classifiers (logistic regression, decision tree, random forest, SVM, KNN, and Bayes) were used to develop nine DLR, 54 ML and clinical–radiological (CR) models based on AP, PP, and DP of DCE‐MRI for evaluating VETC status and association with recurrence. Statistical Tests: The Fleiss kappa, intraclass correlation coefficient, receiver operating characteristic curve, area under the curve (AUC), Delong test and Kaplan–Meier survival analysis. P value <0.05 was considered as statistical significance. Results: Pathological VETC+ were confirmed in 68 patients (training set: 46, validation set: 22). In the validation set, DLR model based on peritumor PP (peri‐PP) phase had the best performance (AUC: 0.844) in comparison to CR (AUC: 0.591) and ML (AUC: 0.672) models. Significant differences in recurrence rates between peri‐PP DLR model‐predicted VETC+ and VETC− status were found. Data Conclusions: The DLR model provides a noninvasive method to discriminate VETC status and prognosis of HCC patients preoperatively. Evidence Level: 4. Technical Efficacy: Stage 2. [ABSTRACT FROM AUTHOR]

Objective: To probe the clinical effect of stem cell transplantation in combination with 308‐nm excimer laser therapy for vitiligo and to analyze its value in clinical application. Methods: A total of 56 patients with stable non‐segmental vitiligo in different parts who were not cured by other therapies visiting our hospital from March 2019 to December 2021 were enrolled as study subjects. They were treated by stem cell transplantation combined with 308‐nm excimer laser therapy. The treatment efficacy was observed and analyzed. Results: Among the 56 patients, 38 (67.85%) and 49 (87.5%) patients were cured at 6 and 12 months after treatment, respectively. Conclusion: Stem cell transplantation combined with 308‐nm excimer laser therapy for vitiligo achieves significant efficacy, with the cure rate far superior to that of other therapies for vitiligo. The therapy is worthy of popularization in the clinic. [ABSTRACT FROM AUTHOR]

Dominance often indicates one or a few species being best suited for resource capture and retention in a given environment. Press perturbations that change availability of limiting resources can restructure competitive hierarchies, allowing new species to capture or retain resources and leaving once dominant species fated to decline. However, dominant species may maintain high abundances even when their new environments no longer favour them due to stochastic processes associated with their high abundance, impeding deterministic processes that would otherwise diminish them.Here, we quantify the persistence of dominance by tracking the rate of decline in dominant species at 90 globally distributed grassland sites under experimentally elevated soil nutrient supply and reduced vertebrate consumer pressure.We found that chronic experimental nutrient addition and vertebrate exclusion caused certain subsets of species to lose dominance more quickly than in control plots. In control plots, perennial species and species with high initial cover maintained dominance for longer than annual species and those with low initial cover respectively. In fertilized plots, species with high initial cover maintained dominance at similar rates to control plots, while those with lower initial cover lost dominance even faster than similar species in controls. High initial cover increased the estimated time to dominance loss more strongly in plots with vertebrate exclosures than in controls. Vertebrate exclosures caused a slight decrease in the persistence of dominance for perennials, while fertilization brought perennials' rate of dominance loss in line with those of annuals. Annual species lost dominance at similar rates regardless of treatments.Synthesis. Collectively, these results point to a strong role of a species' historical abundance in maintaining dominance following environmental perturbations. Because dominant species play an outsized role in driving ecosystem processes, their ability to remain dominant—regardless of environmental conditions—is critical to anticipating expected rates of change in the structure and function of grasslands. Species that maintain dominance while no longer competitively favoured following press perturbations due to their historical abundances may result in community compositions that do not maximize resource capture, a key process of system responses to global change. [ABSTRACT FROM AUTHOR]

Monitoring variations in the virus genome to understand the SARS‐CoV‐2 evolution and spread of the virus is extremely important. Seven early SARS‐CoV‐2 isolates in China were cultured in vitro and were analyzed for their viral infectivity through viral growth assay, tissue culture infectious dose (TCID50) assay, spike protein quantification, and next generation sequencing analysis, and the resultant mutations in spike protein were used to generate the corresponding pseudoviruses for analysis of immune escape from vaccination and postinfection immunity. The results revealed that in vitro cultured SARS‐CoV‐2 virus had much higher mutation frequency (up to ~20 times) than that in infected patients, suggesting that SARS‐CoV‐2 diversify under favorable conditions. Monitoring viral mutations is not only helpful for better understanding of virus evolution and virulence change, but also the key to prevent virus transmission and disease progression. Compared with the D614G reference strain, a pseudovirus strain of SARS‐CoV‐2 was constructed with a high mutation rate site on the spike protein. We found some novel spike mutations during in vitro culture, such as E868Q, conferred further immune escape ability. [ABSTRACT FROM AUTHOR]

Practical implementation of alkali metal batteries currently still faces formidable challenges because of the dendrite growth upon continuous charge/discharge processes and the associated unstable solid–electrolyte interphase. Herein, it is reported that dendrites can be fundamentally mitigated in lithium and sodium metal batteries by regulating the Li+ and Na+ flux using a glass fiber (GF) separator impregnated with polytetrafluoroethylene nanospheres (PTFE‐NSs), which results in homogeneous deposition of Li and Na during charging. The COMSOL Multiphysics simulations reveal that the introduction of negatively charged PTFE‐NSs into the GF separator enhances the local electric field near the anode, thereby boosting the transfer of cations. It is demonstrated that Li//Li and Na//Na symmetric cells utilising a PTFE‐GF separator show outstanding cycle stability of 1245 and 2750 h, respectively, at 0.5 mA cm−2. Moreover, the Li//LiFePO4 and Na//Na3V2(PO4)2F3 full cells exhibit remarkably improved capacity retention when cycled at 1 C, in the presence of a PTFE‐GF separator. The nuclear magnetic resonance spectroscopy studies suggest that the impregnation of PTFE‐NSs into GF helps "liberate" more Li+ and Na+ and changes the coordination interaction between ions and solvents, contributing to the enhanced electrochemical performance. [ABSTRACT FROM AUTHOR]

Human activities are altering ecological communities around the globe. Understanding the implications of these changes requires that we consider the composition of those communities. However, composition can be summarized by many metrics which in turn are influenced by different ecological processes. For example, incidence‐based metrics strongly reflect species gains or losses, while abundance‐based metrics are minimally affected by changes in the abundance of small or uncommon species. Furthermore, metrics might be correlated with different predictors. We used a globally distributed experiment to examine variation in species composition within 60 grasslands on six continents. Each site had an identical experimental and sampling design: 24 plots × 4 years. We expressed compositional variation within each site—not across sites—using abundance‐ and incidence‐based metrics of the magnitude of dissimilarity (Bray–Curtis and Sorensen, respectively), abundance‐ and incidence‐based measures of the relative importance of replacement (balanced variation and species turnover, respectively), and species richness at two scales (per plot‐year [alpha] and per site [gamma]). Average compositional variation among all plot‐years at a site was high and similar to spatial variation among plots in the pretreatment year, but lower among years in untreated plots. For both types of metrics, most variation was due to replacement rather than nestedness. Differences among sites in overall within‐site compositional variation were related to several predictors. Environmental heterogeneity (expressed as the CV of total aboveground plant biomass in unfertilized plots of the site) was an important predictor for most metrics. Biomass production was a predictor of species turnover and of alpha diversity but not of other metrics. Continentality (measured as annual temperature range) was a strong predictor of Sorensen dissimilarity. Metrics of compositional variation are moderately correlated: knowing the magnitude of dissimilarity at a site provides little insight into whether the variation is driven by replacement processes. Overall, our understanding of compositional variation at a site is enhanced by considering multiple metrics simultaneously. Monitoring programs that explicitly incorporate these implications, both when designing sampling strategies and analyzing data, will have a stronger ability to understand the compositional variation of systems and to quantify the impacts of human activities. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the applicability of multidimensional convolutional neural networks (CNNs) together with multiphase contrast‐enhanced CT images on automated detection of diverse focal liver lesions (FLLs). Methods: We trained detection models based on 2.5D and 3D CNN frameworks using 567 patients with 3892 FLLs and validated on a relatively large independent cohort of 1436 patients with 4723 lesions. The detection performance across different phases (arterial, portal venous [PV], and combined phases) was assessed for the 2.5D model. The lesions were divided into two groups with a cutoff size of 20 mm, and further subdivided into four subgroups of <10, 10–20, 20–50, and ≥50 mm, to verify the detection rates for lesions of different sizes for the 2.5D and 3D models. McNemar's test was used to compare the detection sensitivities among different methods. In addition, sensitivity with 95% confidence intervals and free‐response receiver operating characteristics (FROC) curves were plotted for visualization of the detectability. Results: In the 2.5D model, the detection rate of PV phase outperformed arterial phase, and a combination of the two phases further improved the performance over a single phase. The detection sensitivities in the arterial, PV, and combined phases were 0.737 versus 0.802 versus 0.832 for all lesions. The 3D model was superior to the 2.5D model for detecting benign lesions (0.896 vs. 0.807, p < 0.001), malignant lesions (0.940 vs. 0.918, p = 0.013), and all lesions (0.902 vs. 0.832, p < 0.001) regardless of size division. Particularly, the 3D model showed higher sensitivity than the 2.5D model in detecting lesions smaller than 20 mm (0.868 vs. 0.759, p < 0.001). For lesions larger than 20 mm, both the 3D and the 2.5D models achieved excellent detection performance. Conclusions: The proposed CNN detection model was demonstrated to adaptively learn the feature representations of diverse FLLs and generalize well to a large‐scale validation dataset. The use of multiphase significantly improved the detectability of FLLs compared to single phase. 3D CNN framework showed an enhanced capability over the 2.5D in the detection of FLLs, particularly small lesions. The promising performance shows that the proposed CNN detection system could be a powerful clinical tool for the early detection of hepatic tumors. [ABSTRACT FROM AUTHOR]

Increasing evidence indicates that angiogenesis plays a pivotal role in tumor progression. Formin‐like 2 (FMNL2) is well‐known for promoting metastasis; however, the molecular mechanisms by which FMNL2 promotes angiogenesis in colorectal cancer (CRC) remain unclear. Here, we found that FMNL2 promotes angiogenesis and metastasis of CRC in vitro and in vivo. The GDB/FH3 domain of FMNL2 directly interacts with epidermal growth factor‐like protein 6 (EGFL6). Formin‐like 2 promotes EGFL6 paracrine signaling by exosomes to regulate angiogenesis in CRC. Cytoskeleton associated protein 4 (CKAP4) is a downstream target of EGFL6 and is involved in CRC angiogenesis. Epidermal growth factor‐like protein 6 binds to the N‐terminus of CKAP4 to promote the migration of HUVECs by activating the ERK/MMP pathway. These findings suggest that FMNL2 promotes the migration of HUVECs and enhances angiogenesis and tumorigenesis in CRC by regulating the EGFL6/CKAP4/ERK axis. Therefore, the EGFL6/CKAP4/ERK axis could be a candidate therapeutic target for CRC treatment. [ABSTRACT FROM AUTHOR]

Developing highly efficient and stable photocatalysts for the CO2 reduction reaction (CO2RR) remains a great challenge. We designed a Z‐Scheme photocatalyst with N−Cu1−S single‐atom electron bridge (denoted as Cu‐SAEB), which was used to mediate the CO2RR. The production of CO and O2 over Cu‐SAEB is as high as 236.0 and 120.1 μmol g−1 h−1 in the absence of sacrificial agents, respectively, outperforming most previously reported photocatalysts. Notably, the as‐designed Cu‐SAEB is highly stable throughout 30 reaction cycles, totaling 300 h, owing to the strengthened contact interface of Cu‐SAEB, and mediated by the N−Cu1−S atomic structure. Experimental and theoretical calculations indicated that the SAEB greatly promoted the Z‐scheme interfacial charge‐transport process, thus leading to great enhancement of the photocatalytic CO2RR of Cu‐SAEB. This work represents a promising platform for the development of highly efficient and stable photocatalysts that have potential in CO2 conversion applications. [ABSTRACT FROM AUTHOR]

Declines in grassland diversity in response to nutrient addition are a general consequence of global change. This decline in species richness may be driven by multiple underlying processes operating at different time‐scales. Nutrient addition can reduce diversity by enhancing the rate of local extinction via competitive exclusion, or by reducing the rate of colonization by constraining the pool of species able to colonize under new conditions. Partitioning net change into extinction and colonization rates will better delineate the long‐term effect of global change in grasslands.We synthesized changes in richness in response to experimental fertilization with nitrogen, phosphorus and potassium with micronutrients across 30 grasslands. We quantified changes in local richness, colonization, and extinction over 8–10 years of nutrient addition, and compared these rates against control conditions to isolate the effect of nutrient addition from background dynamics.Total richness at steady state in the control plots was the sum of equal, relatively high rates of local colonization and extinction. On aggregate, 30%–35% of initial species were lost and the same proportion of new species were gained at least once over a decade. Absolute turnover increased with site‐level richness but was proportionately greater at lower‐richness sites relative to starting richness. Loss of total richness with nutrient addition, especially N in combination with P or K, was driven by enhanced rates of extinction with a smaller contribution from reduced colonization. Enhanced extinction and reduced colonization were disproportionately among native species, perennials, and forbs. Reduced colonization plateaued after the first few (<5) years after nutrient addition, while enhanced extinction continued throughout the first decade.Synthesis. Our results indicate a high rate of colonizations and extinctions underlying the richness of ambient communities and that nutrient enhancement drives overall declines in diversity primarily by exclusion of previously established species. Moreover, enhanced extinction continues over long time‐scales, suggesting continuous, long‐term community responses and a need for long‐term study to fully realize the extinction impact of increased nutrients on grassland composition. [ABSTRACT FROM AUTHOR]

Reassortment can introduce one or more gene segments of influenza A viruses (IAVs) into another, resulting in novel subtypes. Since 2013, a new outbreak of human highly pathogenic avian influenza has emerged in the Yangtze River Delta (YRD) and South‐Central regions of China. In this study, using Anhui province as an example, we discuss the possible impact of H7N9 IAVs on future influenza epidemics through a series of gene reassortment events. Sixty‐one human H7N9 isolates were obtained from five outbreaks in Anhui province from 2013 to 2019. Bioinformatics analyses revealed that all of them were characterized by low pathogenicity and high human or mammalian tropism and had introduced novel avian influenza A virus (AIV) subtypes such as H7N2, H7N6, H9N9, H5N6, H6N6, and H10N6 through gene reassortment. In reassortment events, Anhui isolates may donate one or more segments of HA, NA, and the six internal protein‐coding genes for the novel subtype AIVs. Our study revealed that H7N9, H9N2, and H5N1 can serve as stable and persistent gene pools for AIVs in the YRD and South‐Central regions of China. Novel AIV subtypes might be generated continuously by reassortment. These AIVs may have obtained human‐type receptor‐binding abilities from their donors and prefer binding to them, which can cause human epidemics through accidental spillover infections. Facing the continual threat of emerging avian influenza, constant monitoring of AIVs should be conducted closely for agricultural and public health. [ABSTRACT FROM AUTHOR]

Global change drivers, such as anthropogenic nutrient inputs, are increasing globally. Nutrient deposition simultaneously alters plant biodiversity, species composition and ecosystem processes like aboveground biomass production. These changes are underpinned by species extinction, colonisation and shifting relative abundance. Here, we use the Price equation to quantify and link the contributions of species that are lost, gained or that persist to change in aboveground biomass in 59 experimental grassland sites. Under ambient (control) conditions, compositional and biomass turnover was high, and losses (i.e. local extinctions) were balanced by gains (i.e. colonisation). Under fertilisation, the decline in species richness resulted from increased species loss and decreases in species gained. Biomass increase under fertilisation resulted mostly from species that persist and to a lesser extent from species gained. Drivers of ecological change can interact relatively independently with diversity, composition and ecosystem processes and functions such as aboveground biomass due to the individual contributions of species lost, gained or persisting. [ABSTRACT FROM AUTHOR]

A profound understanding on the corrosion kinetics and mechanisms is crucial to help improve the corrosion resistance of alloys. Corrosion of aluminum alloys is very complex due to the interplay among a bunch of electrochemical reactions, and the influences of diversified precipitates. In this work, a new multi‐phase field method is constructed to quantitatively analyze the corrosion kinetics of aluminum alloys, and a semi‐implicit algorithm is developed to solve the numerical divergence resulted by the terms of reactions in concentration equations. Then, this new method is successfully used to simulate the pitting processes in the cases of a uniform matrix, a polycrystalline matrix, and a non‐uniform matrix with secondary phase for aluminum alloys. More generally, the framework of this multi‐phase field model can potentially be used to study the corrosion of other alloy systems, and microstructure evolution of a broad range of electrochemistry processes. [ABSTRACT FROM AUTHOR]

Drawing on social information processing theory, the current study investigates the relationship between top management team (TMT) responsible leadership and employee organizational citizenship behavior for the environment (OCBE) from a vertical perspective, and whether green human resource management (GHRM) and employee environmental felt‐responsibility can play a sequential mediating role between them. Totally, 102 middle‐level managers and 527 employees in 102 Chinese teams voluntarily participated in our study. Drawing on above data, our study verifies that TMT responsible leadership was positively associated with both GHRM and employee environmental felt‐responsibility. In addition, GHRM mediated the positive effects of TMT responsible leadership and employee environmental felt‐responsibility. Also, GHRM can further promote employee OCBE through employee environmental felt‐responsibility. Overall, the positive relationship between TMT responsible leadership and employee OCBE was sequentially mediated by GHRM and employee environmental felt‐responsibility. Therefore, the current study shows the way to achieve corporate environmental sustainability strategy. [ABSTRACT FROM AUTHOR]

Objectives: Artificial intelligence (AI) has been proved to be a highly efficient tool for COVID‐19 diagnosis, but the large data size and heavy label force required for algorithm development and the poor generalizability of AI algorithms, to some extent, limit the application of AI technology in clinical practice. The aim of this study is to develop an AI algorithm with high robustness using limited chest CT data for COVID‐19 discrimination. Methods: A three dimensional algorithm that combined multi‐instance learning with the LSTM architecture (3DMTM) was developed for differentiating COVID‐19 from community acquired pneumonia (CAP) while logistic regression (LR), k‐nearest neighbor (KNN), support vector machine (SVM), and a three dimensional convolutional neural network set for comparison. Totally, 515 patients with or without COVID‐19 between December 2019 and March 2020 from five different hospitals were recruited and divided into relatively large (150 COVID‐19 and 183 CAP cases) and relatively small datasets (17 COVID‐19 and 35 CAP cases) for either training or validation and another independent dataset (37 COVID‐19 and 93 CAP cases) for external test. Area under the receiver operating characteristic curve (AUC), sensitivity, specificity, precision, accuracy, F1 score, and G‐mean were utilized for performance evaluation. Results: In the external test cohort, the relatively large data‐based 3DMTM‐LD achieved an AUC of 0.956 (95% confidence interval, 95% CI, 0.929∼0.982) with 86.2% and 98.0% for its sensitivity and specificity. 3DMTM‐SD got an AUC of 0.937 (95% CI, 0.909∼0.965), while the AUC of 3DCM‐SD decreased dramatically to 0.714 (95% CI, 0.649∼0.780) with training data reduction. KNN‐MMSD, LR‐MMSD, SVM‐MMSD, and 3DCM‐MMSD benefited significantly from the inclusion of clinical information while models trained with relatively large dataset got slight performance improvement in COVID‐19 discrimination. 3DMTM, trained with either CT or multi‐modal data, presented comparably excellent performance in COVID‐19 discrimination. Conclusions: The 3DMTM algorithm presented excellent robustness for COVID‐19 discrimination with limited CT data. 3DMTM based on CT data performed comparably in COVID‐19 discrimination with that trained with multi‐modal information. Clinical information could improve the performance of KNN, LR, SVM, and 3DCM in COVID‐19 discrimination, especially in the scenario with limited data for training. [ABSTRACT FROM AUTHOR]

Nutrients and herbivores are well‐known drivers of grassland diversity and stability in local communities. However, whether they interact to impact the stability of aboveground biomass and whether these effects depend on spatial scales remain unknown. It is also unclear whether nutrients and herbivores impact stability via different facets of plant diversity including species richness, evenness, and changes in community composition through time and space. We used a replicated experiment adding nutrients and excluding herbivores for 5 years in 34 global grasslands to explore these questions. We found that both nutrient addition and herbivore exclusion alone reduced stability at the larger spatial scale (aggregated local communities; gamma stability), but through different pathways. Nutrient addition reduced gamma stability primarily by increasing changes in local community composition over time, which was mainly driven by species replacement. Herbivore exclusion reduced gamma stability primarily by decreasing asynchronous dynamics among local communities (spatial asynchrony). Their interaction weakly increased gamma stability by increasing spatial asynchrony. Our findings indicate that disentangling the processes operating at different spatial scales may improve conservation and management aiming at maintaining the ability of ecosystems to reliably provide functions and services for humanity. [ABSTRACT FROM AUTHOR]

Nutrient enrichment can simultaneously increase and destabilise plant biomass production, with co‐limitation by multiple nutrients potentially intensifying these effects. Here, we test how factorial additions of nitrogen (N), phosphorus (P) and potassium with essential nutrients (K+) affect the stability (mean/standard deviation) of aboveground biomass in 34 grasslands over 7 years. Destabilisation with fertilisation was prevalent but was driven by single nutrients, not synergistic nutrient interactions. On average, N‐based treatments increased mean biomass production by 21–51% but increased its standard deviation by 40–68% and so consistently reduced stability. Adding P increased interannual variability and reduced stability without altering mean biomass, while K+ had no general effects. Declines in stability were largest in the most nutrient‐limited grasslands, or where nutrients reduced species richness or intensified species synchrony. We show that nutrients can differentially impact the stability of biomass production, with N and P in particular disproportionately increasing its interannual variability. [ABSTRACT FROM AUTHOR]

Pixelated two‐dimensional (2‐D) optical wireless communication systems, with intensity‐modulation and direct‐detection (IM/DD), are capable to transmit data at high data rates by modulating the data into image intensities at the transmitter. Frequency division modulation (FDM) and space‐domain modulation (SDM) are two common modulation schemes in a 2‐D pixelated system. Generally, FDM is preferred because FDM benefits from the capability of controlling the spectrum of transmitting signals so that the output signal could be shaped according to the characteristics of a particular optical channel. However, the computational complexity of FDM is relatively high and complex computation is needed at both the transmitter and the receiver. In this work, a fast orthogonal frequency‐division multiplexing (FOFDM) modulation which employs 2‐D inverse discrete cosine transform (IDCT2) instead of 2‐D inverse Fourier transform (IFFT2) is presented. As the image intensities must be real and positive, two schemes are hereby introduced to generate unipolar image intensities. The proposed FOFDM is simulated and discussed in terms of key characterisations including the signal spectrum, spectral efficiency, peak to average power ratio (PAPR), bit error ratio (BER) and computational complexity. Compared with traditional spatial orthogonal frequency‐division multiplexing (OFDM) based on IFFT2, the proposed FOFDM has similar BER performance, twice the spatial efficiency for the same constellation size, lower computational complexity and a much simpler structure in the transmitter. [ABSTRACT FROM AUTHOR]

Land abandonment has been increasing in recent decades in Europe, usually accompanied by biodiversity decline. Whether livestock grazing and mowing can safeguard biodiversity across spatial scales in the long term is unclear.Using a 48‐year experiment in a salt marsh, we compared land abandonment (without grazing and mowing) and seven management regimes including cattle grazing, early season mowing, late season mowing, both early and late season mowing, and grazing plus each of the mowing regimes on plant diversity at the local and larger scales (i.e. aggregated local communities). Also, we compared their effects on community composition (both in identities and abundances) in time and space.Under land abandonment, plant diversity declined in the local communities and this decline became more apparent at the larger scale, particularly for graminoids and halophytes. All management regimes, except for late season mowing, maintained plant diversity at these scales.Local plant communities under all treatments underwent different successional trajectories, in the end, diverged from their initial state except for that under grazing (a cyclic succession). Year‐to‐year changes in local community composition remained at a similar level over time under land abandonment and grazing plus early season mowing while it changed under other treatments. Vegetation homogenized at the larger scale over time under land abandonment while vegetation remained heterogeneous under all management regimes.Synthesis. Our experiment suggests that late season mowing may not be sustainable to conserve plant diversity in salt marshes. Other management regimes can maintain plant diversity across spatial scales and vegetation heterogeneity at the larger scale in the long term, but local community composition may change over time. [ABSTRACT FROM AUTHOR]

Purpose: Liver tumor segmentation is a crucial prerequisite for computer‐aided diagnosis of liver tumors. In the clinical diagnosis of liver tumors, radiologists usually examine multiphase CT images as these images provide abundant and complementary information of tumors. However, most known automatic segmentation methods extract tumor features from CT images merely of a single phase, in which valuable multiphase information is ignored. Therefore, it is highly demanded to develop a method effectively incorporating multiphase information for automatic and accurate liver tumor segmentation. Methods: In this paper, we propose a phase attention residual network (PA‐ResSeg) to model multiphase features for accurate liver tumor segmentation. A phase attention (PA) is newly proposed to additionally exploit the images of arterial (ART) phase to facilitate the segmentation of portal venous (PV) phase. The PA block consists of an intraphase attention (intra‐PA) module and an interphase attention (inter‐PA) module to capture channel‐wise self‐dependencies and cross‐phase interdependencies, respectively. Thus, it enables the network to learn more representative multiphase features by refining the PV features according to the channel dependencies and recalibrating the ART features based on the learned interdependencies between phases. We propose a PA‐based multiscale fusion (MSF) architecture to embed the PA blocks in the network at multiple levels along the encoding path to fuse multiscale features from multiphase images. Moreover, a 3D boundary‐enhanced loss (BE‐loss) is proposed for training to make the network more sensitive to boundaries. Results: To evaluate the performance of our proposed PA‐ResSeg, we conducted experiments on a multiphase CT dataset of focal liver lesions (MPCT‐FLLs). Experimental results show the effectiveness of the proposed method by achieving a dice per case (DPC) of 0.7787, a dice global (DG) of 0.8682, a volumetric overlap error (VOE) of 0.3328, and a relative volume difference (RVD) of 0.0443 on the MPCT‐FLLs. Furthermore, to validate the effectiveness and robustness of PA‐ResSeg, we conducted extra experiments on another multiphase liver tumor dataset and obtained a DPC of 0.8290, a DG of 0.9132, a VOE of 0.2637, and a RVD of 0.0163. The proposed method shows its robustness and generalization capability in different datasets and different backbones. Conclusions: The study demonstrates that our method can effectively model information from multiphase CT images to segment liver tumors and outperforms other state‐of‐the‐art methods. The PA‐based MSF method can learn more representative multiphase features at multiple scales and thereby improve the segmentation performance. Besides, the proposed 3D BE‐loss is conducive to tumor boundary segmentation by enforcing the network focus on boundary regions and marginal slices. Experimental results evaluated by quantitative metrics demonstrate the superiority of our PA‐ResSeg over the best‐known methods. [ABSTRACT FROM AUTHOR]

The porous carbon nanosphere with multiple heteroatom doping derived from silicon oxycarbonitride (SiOCN) with an interconnected carbon and silica domains is reported as a robust host of the sulfur cathode for lithium–sulfur batteries. The synthesis of the porous carbon nanosphere (SiOCN‐H) is straightforward etching spherical SiOCN prepared through pyrolysis of a Schiff‐base‐SiO2 precursor. The pore structure of SiOCN‐H can be easily adjusted by altering the amount of tetraethyl orthosilicate added in the aldimine condensation reaction of 3‐aminopropyl‐triethoxysilane with glutaraldehyde. The optimized sample of SiOCN‐H‐1 possesses a larger pore volume of 1.433 cm3 g−1 and contains multiple heteroatoms of Si, O, and N with a total amount of about 21 wt%. The sulfur cathode based on SiOCN‐H‐1 exhibits decent cycling performance, retaining 77.2% of the initial capacity at 0.2C after 100 cycles. At 0.5C, the S/SiOCN‐H‐1 cathode still maintains remarkable cycling stability, delivering a reversible discharge capacity of 540 mAh g−1 after 400 cycles with a low decay of 0.076% per cycle. The porous spherical structure and the chemical bonding capability of doped heteroatoms in SiOCN‐H‐1 primarily contribute to the high performances of the S/SiOCN‐H‐1 cathode by alleviating the dissolution and shuttle effect of polysulfides. [ABSTRACT FROM AUTHOR]

Sub‐heading: Compound hemizygous variants in SERPINA7 gene. Background: Thyroxine‐binding globulin (TBG) is encoded by SERPINA7 (OMIM. 314200) which is located on Xq22.3. SERPINA7 variants caused TBG deficiency which does not require treatment, but the decreased thyroxine may be misdiagnosed as hypothyroidism. We discovered some variants of TBG caused by alterations that differ from previously reported. Materials and Methods: In this study, we enrolled 32 subjects from 10 families and sequenced the SERPINA7 genes of TBG‐deficient subjects. Then, variants were analyzed to assess their effect on TBG expression and secretion. Bioinformatics database, protein structure, and dynamics simulation were used to evaluate the deleterious effects. Finally, we identified 2 novel and 4 known variants, and found 26 of 30 subjects carried the p.L303F. The DynaMut predictions indicated the variants (p.E91K, p.I92T, p.R294C, and p.L303F) exhibited decreased stability. Conclusion: Analyses revealed the p.L303F change the protein stability and flexibility, and it had an impact on the function of TBG, but when coexisted with other variants it might change the conformational structure of the protein and aggravate the damage to the protein. We speculated that the existence of a higher number of variants resulted in lower TBG secretion. [ABSTRACT FROM AUTHOR]

Fluorescence guided photodynamic therapy (FL‐PDT) offers the great opportunity for realizing personalized medicine in the treatment of cancer. Aggregation‐induced emission luminogens (AIEgens) with efficient emission and reactive oxygen species (ROS) generation even in the aggregated state are the ideal FL‐PDT photosensitizers to overcome the quenched fluorescence and ROS that traditional photosensitizers faced in PDT. Moreover, considering the higher levels of H2O2 in cancer cells than in normal cells and the fact that lipid droplet (LD) accumulation correlates to the enhanced survival rate of cancer cells in hypoxic conditions, it will be very interesting and rewarding to develop a LD‐targeted, H2O2 activatable AIE‐active photosensitizer for FL‐PDT. Thereafter, a LD‐targeted fluorescent probe TPECNPB is fabricated for H2O2‐activatable fluorescence guided PDT of cancer cells. AIE‐active TPECNPB exhibits the unique features of large Stokes shift (175 nm), superior photostability, and excellent selectivity toward H2O2. TPECNPB is able to selectively accumulate in LD and is activated by endogenous H2O2 for light‐up bioimaging in live MCF‐7 cells. In addition, H2O2‐activatable singlet oxygen generation and PDT of cancer cells has also been successfully implemented with TPECNPB. These prominent parameters would make TPECNPB a powerful toolbox for H2O2‐activatable and LD‐targetable fluorescence guided PDT of cancer cells. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is an important index of soil drought, and it directly controls the energy balance and water cycle of the land surface. As an indicator and amplifier of global warming, the Tibetan Plateau (TP) is becoming warmer and wetter. Because of its particular geographical environment, large‐scale measurements of SM on the TP can only be achieved by satellite remote sensing. The resolution of current SM product of the Soil Moisture Active Passive (SMAP) satellite is 36 km, which is insufficient for many practical applications. In this study, the Moderate Resolution Imaging Spectroradiometer (MODIS) and Digital Elevation Model (DEM) are applied to increase the resolution of SM down to 1 km using the Random Forest (RF) algorithm. The preliminary results of the proposed algorithm are evaluated by station observations and other reanalysis products. The downscaled results are more consistent with the in situ observations, the Land Data Assimilation System (CLDAS) from China Meteorological Administration (CMA), and the Global Land Data Assimilation System (GLDAS) from National Aeronautics and Space Administration (NASA) than the original SMAP product. The downscaling algorithm is most effective for grasslands. It is demonstrated that high‐resolution SM products can be generated by fusing various features using machine‐learning algorithms. Key Points: A machine‐learning algorithm is proposed to increase the resolution of soil moisture products of remote sensing on the Tibetan PlateauTopographical features are applied to estimate soil moisture in complex terrains, so that the accuracy of estimation could be improvedRandom forest algorithm is applied to combine various features, and the results are expected to well fit the real situation [ABSTRACT FROM AUTHOR]

The long‐term influence of persistent small herbivores on successional plant community configuration is rarely studied. We used a herbivore exclusion experiment along the successional gradient in a salt‐marsh system, to investigate the effects of hares and geese, and hares alone, on plant diversity at five successional stages (the earliest, two early, the intermediate and the late successional stages) in the short and long term, i.e. 7 and 22 years, respectively.Plant diversity declined over time at all successional stages except for the earliest one. Small herbivores slowed down species decline, but only at one early successional stage.Small herbivores slowed down species decline via decreasing dominance of preferred grass Festuca rubra in the short term, and less preferred Elytrigia atherica in the long term. The effects of hares and geese were more pronounced than hares alone, indicating an important additive role of geese, especially in the long term.Synthesis. Small herbivores can have a strong and long‐lasting impact on plant diversity, but it highly depends on the abundance of small herbivores, which in turn depends on the quality and abundance of forage plants. A diverse herbivore community may have more positive effects on regulating plant communities. [ABSTRACT FROM AUTHOR]

Abstract: Amorphous Si2BC3N nanopowders (NPs) were heated at 1000‐1700°C temperatures for 30 minutes in 1 atm N2. The changes in phases, chemical bonds, and microstructures were investigated by XRD, XPS, NMR, TEM, and first‐principles calculation. Increases in heating temperatures lead to the nucleation and growth of SiC and BN(C) grains, along with partial transformation of SiC4 units from amorphous to β/α‐SiC, and collapse of B–C–N bonds. SiC nucleates prior to BN(C) at 1 atm, while it goes in the opposite order at high pressures (≥1 GPa). High pressures also shift the initial temperatures of crystallization of amorphous Si2BC3N NPs from 1400°C (1 atm) to 1150°C (5 GPa). [ABSTRACT FROM AUTHOR]

Abstract: Amorphous boron‐rich SiBCN were prepared by high‐energy ball‐milling of the mixtures of Si, graphite, h‐BN, and inorganic boron, which acted as extra boron source. The solid‐state amorphization, thermal stability, and crystallization of the boron‐rich SiBCN were studied in detail. It was suggested that mechanical alloying can drive solid‐state amorphization but also can be an initiation step for the nucleation of nanocrystals. The amorphous networks of Si‐C, C‐B, C‐C, C‐N, B‐N, and C‐B‐N bonds are detected by XPS; however, solid‐state NMR further confirms the formation of a new chemical environment around B atoms, BC3. The increases in boron content improve the thermal stability of SiBCN ceramics but weaken their oxidation resistance. Nano‐SiC crystallizes first while BN(C) forms subsequently. Boron promoting SiC crystallization may result from the reduced hindering effects of B‐N‐C nanodomains that retard SiC crystallization. [ABSTRACT FROM AUTHOR]

Hydroxyapatite nanoparticles (HAP-NPs) have been extensively developed as drug carriers, bone implants, coating materials, etc. in the human body. However, research focusing on the potential side effects of HAP-NPs on the mitochondria-associated energy metabolism in liver cells is lacking. In this study, HAP-NPs with a long diameter of 80 nm and a short diameter of 20 nm were evaluated for their ability to induce mitochondrial energy metabolism dysfunction in vitro and in vivo. In the in vitro system, the buffalo rat hepatocyte (BRL) cell line was directly exposed to the HAP-NPs. The results of these experiments showed that the HAP-NPs induced inhibition of mitochondrial dehydrogenase activity, which was accompanied by a decrease in the mitochondrial membrane potential (MMP). In addition, HAP-NPs elevated the hepatic levels of reactive oxygen species (ROS) and malondialdehyde (MDA) and decreased the levels of GSH and SOD. These data indicated that HAP-NPs induced a lowered rate of electron transfer in the mitochondrial respiratory chain, accompanied by a decrease in the activity of the mitochondrial respiratory chain complexes I, II and III. Furthermore, HAP-NPs induced a decline in the enzymatic expression in the Krebs cycle. We also investigated the role of Kupffer cells (KCs, rat-derived) in the effects induced by the HAP-NPs. The supernatant from the HAP-NP-treated KCs was used to stimulate the BRL cells. We observed that the HAP-NPs had the ability to induce KC activation. The activation of KCs then led to the release of tumor necrosis factor-α (TNF-α), nitric oxide (NO) and reactive oxygen species (ROS), and induced the inhibition of mitochondrial respiratory chain complexes I, II and III in the BRL cells. In the in vivo study, the TEM examination revealed mitochondrial swelling and vacuolar degeneration in the HAP-NP-treated hepatocytes. In addition, the amount of succinate (Suc), an intermediate in the mitochondrial Krebs cycle, also declined in the 1H NMR spectroscopic measurements. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are a class of new-found RNA molecules that have a special covalent loop structure without a 5′ cap and 3′ tail. Researchers have found that circRNAs may be generated by intron-pairing-driven or lariat-driven circularization. They are cleared up by way of extracellular vesicles. They have some advantages such as stability, conservation, and tissue specificity. By serving as sponges of microRNAs, interacting with long non-coding RNAs, mRNA, or proteins, circRNAs regulate gene expression at transcriptional and post-transcriptional levels and contribute to carcinogenesis. In recent years, circRNAs have been found to be correlated with many cancers including hepatocellular carcinoma, one of the most common cancers with high mortality. This article will first introduce the biogenesis, properties, and functions of circRNAs. Then we focus on the molecular mechanisms underlying some circRNAs, including hsa_circ_0001649, hsa_circ_0005075, and cerebellar degeneration-related protein 1 antisense, on hepatocellular carcinoma metastasis. [ABSTRACT FROM AUTHOR]

To investigate the multi-infection patterns and type competition for human papillomavirus (HPV) in Chinese clinic attending women and evaluate the association between the infection status and cancer risk. Three hundred and thirty-two HPV-DNA-positive samples were genotyped for 21 HPVs and tested for 13 types of HPV neutralizing antibody using pseudoviron-based assay. Odds ratios (ORs) were calculated to evaluate the coinfection patterns for both DNA and neutralizing antibody (NAb), and the associations of HSIL+ with HPV DNA and NAb. Of the 332 HPV-DNA-positive subjects, 279 (84.0%) were detected as NAb positive. Multi-positive results were identified in 23.2% (77/332) HPV DNA tests and 60.2% (168/279) HPV NAb assays. The NAb titers for the multiple-positive samples (geometric mean 214) were significantly higher than the single-positive samples (geometric mean 114) ( P < 0.01). HPV16-HPV52 was identified as a type-competition pair for both HPV DNA (OR = 0.09; 95%CI = 0.02-0.42) and NAb (OR = 0.27; 95%CI = 0.11-0.69) data. Compared to other types, HPV16 DNA was associated significantly with high risk of HSIL+ (OR = 2.57; 95%CI = 1.23-5.38). HPV16-HPV52 was identified as a potential type-competition pair, which might result in the type modulation with the implementation of the approved bi- or quadri-valent vaccines. J. Med. Virol. 88:1989-1998, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The crystallization behavior of amorphous Si2BC3N monoliths by heating at 1000°C-1400°C and 5 GPa was investigated with the special attention to the nucleation mechanisms of β-SiC and BN(C) phases. Nanoscale puckered structures arising in particle bridging areas were found and its evolution behavior well reflected the nucleation process of nanocrystallites. The temperature-dependent crystallization of amorphous Si2BC3N monoliths at 5 GPa passes through four stages: The material remains amorphous below 1100°C. It undergoes partial phase segregation (1100°C-1200°C), followed by initiation of nucleation (1200°C-1250°C), and then nucleation and growth of β-SiC and turbostratic BN(C) crystallites (>1250°C). The first principles calculation indicates the nucleation precedence of BN(C) phase over β-SiC. BN(C) nucleates preferentially at bridges between ceramic particles causing SiC to concentrate in particle interiors thus forming capsule-like structures. [ABSTRACT FROM AUTHOR]

ABSTRACT As hydroxyapatite nanoparticles (HA NPs) are increasingly used in biomedical and biotechnological fields, risk assessment of HA NPs has attracted extensive attention. Nevertheless, little is known about the potential adverse effects of HA NPs on normal hepatocytes and the liver. In the present study, we conducted an in vitro study in which 80-nm HA NPs were incubated with normal Buffalo rat liver (BRL) cells. By analyzing the changes in cell viability, apoptosis/necrosis and the mitogen-activated protein kinase (MAPK) signaling pathway, we investigated the cytotoxicity and potential mechanism of HA NPs in hepatocytes. Furthermore, we used the serum hematology and histopathology examinations to explore the in vivo effects of HA NPs on the structure and function of the liver. Our results showed that exposure to HA NPs at a concentration above 200 µg ml−1 decreased cell viability, increased levels of lactate dehydrogenase (LDH) leakage, induced apoptosis and necrosis, and triggered the MAPK signaling pathway in BRL cells in a dose-dependent manner. Moreover, our in vivo study indicated that HA NPs increased the white blood cell count (WBC) and the levels of tumor necrosis factor-α (TNF-α), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the serum, caused inflammatory cell infiltration at the portal area in the liver, and induced hepatic oxidative stress with elevated levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA). These data demonstrate that at certain concentrations, 80-nm HA NPs cause hepatotoxicity and liver injury. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Highly C-axis oriented ZnO thin film was manufactured by radio-frequency magnetron sputtering technique on Si (111) substrate. The main objective was to study the influence of rapid thermal annealing (RTA) temperature on the structure and interfacial characteristic of ZnO thin films. X-ray diffraction results showed that the ZnO thin films annealed at 600 °C by RTA technique had a perfect C-axis preferred orientation compared to the other ZnO thin films, and the full width at half maximum of ZnO (002) rocking curve measurements indicted that the RTA-annealed ZnO thin films possessed better crystal structure. Atom force microscopy displayed that the grain size of RTA-annealed ZnO thin films was fine and uniform compared with the as-deposited ZnO thin films, although the grains grew in RTA process and the root meant square roughness was smaller than that of as-deposited films. High-resolution transmission electron microscopy showed that there was an obvious amorphous layer between ZnO thin films and Si substrate, but the RTA-annealed ZnO thin films exhibited larger and denser columnar structure and a preferred orientation with highly c axis perpendicular to the amorphous layer. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of esters via reductive coupling of N-tosylhydrazones with carboxylic acids under metal-free conditions has been developed. Various functional groups were found to be tolerable under the reaction conditions to afford low to good yields. [ABSTRACT FROM AUTHOR]

A diagram is presented which presents the chemical structure of the catalysts of phosphine domino reactions of sulfonylhydrazone and alkynyl ketones and the construction of pyrazoloquinazoline derivatives.