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【Objective】 Frequent droughts have significantly impacted agricultural productivity and ecological health of the Loess Plateau. This study investigates the characteristics and driving factors of dry-wet evolution in the region. 【Method】 The analysis was based on meteorological data, including temperature, precipitation, relative humidity, sunshine hours, and wind speed, measured from 1961 to 2020 at 71 weather stations across the Loess Plateau. The changes in wet and dry spells and their underlying determinants were analyzed using standardized precipitation evapotranspiration index (SPEI), Mann Kendall test, and run length theory. 【Result】 Temporally, temperature showed a significant increase, while wind speed, relative humidity and sunshine hours showed significant decreases from 1961 to 2020. In contrast, precipitation showed a weak decrease, while ET0 (reference crop evapotranspiration) exhibited a first increase followed by a decrease during this period. Spatially, the Northwest saw increased precipitation and decreased ET0. Conversely, the Northeast experienced declines in both precipitation and ET0. From 1999 onward, the SPEI showed an initial decrease followed by an increase. The Southeast experienced high drought frequency but with shorter durations and lower severity, extreme drought events in which were rare. In contrast, the Northwest had fewer but more severe and prolonged droughts. Rising temperatures, increasing precipitation and decreasing ET0 were the primary drivers of dry-wet alterations. ET0 had a stronger influence on dryness and wetness patterns than precipitation. The correlation between the mid-latitude westerly belt, sunspot activity, and SPEI was weak, indicating limited influence of large-scale atmospheric and solar factors. 【Conclusion】 The Loess Plateau showed a warm-drying trend from 1961 to 1999, followed by a warm-wetting trend thereafter. These findings improve our understanding of hydrological changes and help develop mitigating strategies for managing drought and water resources in the region.

【Background and Objective】 Groundwater is a vital resource in the Middle Reaches of the Yellow River basin, crucial for maintaining soil and water ecological functions. However, its depletion due to insufficient supply and excessive consumption has led to groundwater drought. Amidst the increasing demand for groundwater in the region, uncertainties persist regarding its ability to meet ecological and consumption demand. Evaluating groundwater drought is hence imperative to ensure sustainable development of the region. This study aims to assess the spatiotemporal evolution in groundwater drought and its consequence for vegetation growth. 【Method】 This study was based on the GRACE/GRACE-FO data and GLDAS data measured from April 2002 to December 2021 in the Middle Reaches of the Yellow River Basin, from which we analyzed the groundwater storage anomaly and estimated the standardized groundwater drought index (SGDI). The spatiotemporal variation in groundwater drought was calculated using the run theory, the modified Mann-Kendall trend test, and the Spearman correlation analysis. The impact of vegetation on groundwater drought and its determinants was analyzed using detrended NDVI. 【Result】 ① Temporally, terrestrial water storage anomaly, surface water storage anomaly and groundwater storage anomaly in the basin changed at the rates of -0.022 mm/d, 0.005 mm/d, and -0.027 mm/d, respectively. Spatially, terrestrial water storage anomaly and groundwater storage anomaly were distributed unevenly in the basin. ② Temporal variation in groundwater drought in the basin had been in increase, with a total of 65 months occurring drought during the studied period, including six severe droughts and fourteen extreme droughts. Between 2016 and 2021, there were multiple consecutive groundwater droughts, including severe and extreme droughts after 2018. The most extreme drought from 2002 to 2021 was in October 2021. The Theil-Sen slope of SGDI in the basin was -4.10×10-4/d, which passed the MMK trend test, indicating there is a significant increasing trend of groundwater drought in the future. ③ In October 2021, the proportion of drought-affected areas in the basin were 95.81%, in which 64.66% were extreme drought. The Theil-Sen slope of SGDI varied spatially in the range of -0.014 to 0.007 per month. The groundwater drought in the north and east of the basin had increased significantly, with areas reaching 63.02% and drought tendency increasing from the southwest to the northeast. ④ The driving effect of vegetation changes on groundwater drought is not significant. 【Conclusion】 Groundwater drought in the Middle Reaches of the Yellow River Basin has intensified, characterized by an expanded drought areas, increased drought events, and a significant upward trend in drought. Groundwater drought did not result in a significant impact on vegetation. These findings underscore the urgent need to protect groundwater resource and mitigate its adverse impact on ecology and socio-economic development of the region.

Abstract The Amur tiger is currently confronted with challenges of anthropogenic development, leading to its population becoming fragmented into two geographically isolated groups: smaller and larger ones. Small and isolated populations frequently face a greater extinction risk, yet the small tiger population’s genetic status and survival potential have not been assessed. Here, a total of 210 samples of suspected Amur tiger feces were collected from this small population, and the genetic background and population survival potentials were assessed by using 14 microsatellite loci. Our results demonstrated that the mean number of alleles in all loci was 3.7 and expected heterozygosity was 0.6, indicating a comparatively lower level of population genetic diversity compared to previously reported studies on other subspecies. The genetic estimates of effective population size (Ne) and the Ne/N ratio were merely 7.6 and 0.152, respectively, representing lower values in comparison to the Amur tiger population in Sikhote-Alin (the larger group). However, multiple methods have indicated the possibility of genetic divergence within our isolated population under study. Meanwhile, the maximum kinship recorded was 0.441, and the mean inbreeding coefficient stood at 0.0868, both of which are higher than those observed in other endangered species, such as the African lion and the grey wolf. Additionally, we have identified a significant risk of future extinction if the lethal equivalents were to reach 6.26, which is higher than that of other large carnivores. Further, our simulation results indicated that an increase in the number of breeding females would enhance the prospects of this population. In summary, our findings provide a critical theoretical basis for further bailout strategies concerning Amur tigers.

Abstract Hiptage yangshuoensis K.Tan & K.S.Nguyen, a new species of Hiptage collected from a karst cliff close to the Lijiang River, Northeast of Guangxi Zhuang Autonomous Region, China, is described and illustrated based on molecular and morphological data. Hiptage yangshuoensis shares some morphological similarities with the H. multiflora F.N.Wei, but easily distinguished by its long pedicels with articulate at top, one large calyx gland, oblanceolate middle wing and lanceolate lateral wings of samara, and young branch covered rusty sericeous. The new species status is also supported by molecular phylogenetic analyses based on nuclear ribosome internal transcribed spacer (nrITS), which showed distinct systematic distinctiveness from the most morphologically similar species, H. multiflora.

Natural gas dehydration is a critical process in natural gas extraction and transportation, and the membrane separation method is the most suitable technology for gas dehydration. In this paper, based on molecular dynamics theory, we investigate the performance of a metal–organic composite membrane (ZIF-90 membrane) in natural gas dehydration. The paper elucidates the adsorption, diffusion, permeation, and separation mechanisms of water and methane with the ZIF-90 membrane, and clarifies the influence of temperature on gas separation. The results show that (1) the diffusion energy barrier and pore size are the primary factors in achieving the separation of water and methane. The diffusion energy barriers for the two molecules (CH4 and H2O) are ΔE(CH4) = 155.5 meV and ΔE(H2O) = 50.1 meV, respectively. (2) The ZIF-90 is more selective of H2O, which is mainly due to the strong interaction between the H2O molecule and the polar functional groups (such as aldehyde groups) within the ZIF-90. (3) A higher temperature accelerates the gas separation process. The higher the temperature is, the faster the separation process is. (4) The pore radius is identified as the intrinsic mechanism enabling the separation of water and methane in ZIF-90 membranes.

Abstract Flexible electronic sensors are receiving numerous research interests for their potential in electronic skins (e‐skins), wearable human‐machine interfacing, and smart diagnostic healthcare sensing. However, the preparation of multifunctional flexible electronics with high sensitivity, broad sensing range, fast response, efficient healability, and reliable antibacterial capability is still a substantial challenge. Herein, bioinspired by the highly sensitive human skin microstructure (protective epidermis/spinous sensing structure/nerve conduction network), a skin bionic multifunctional electronics is prepared by face‐to‐face assembly of a newly prepared healable, recyclable, and antibacterial polyurethane elastomer matrix with conductive MXene nanosheets‐coated microdome array after ingenious templating method as protective epidermis layer/sensing layer, and an interdigitated electrode as signal transmission layer. The polyurethane elastomer matrix functionalized with triple dynamic bonds (reversible hydrogen bonds, oxime carbamate bonds, and copper (II) ion coordination bonds) is newly prepared, demonstrating excellent healability with highly healing efficiency, robust recyclability, and reliable antibacterial capability, as well as good biocompatibility. Benefiting from the superior mechanical performance of the polyurethane elastomer matrix and the unique skin bionic microstructure of the sensor, the as‐assembled flexible electronics exhibit admirable sensing performances featuring ultrahigh sensitivity (up to 1573.05 kPa−1), broad sensing range (up to 325 kPa), good reproducibility, the fast response time (≈4 ms), and low detection limit (≈0.98 Pa) in diagnostic human healthcare monitoring, excellent healability, and reliable antibacterial performance.

Colon cancer is increasing worldwide and is commonly regarded as hormone independent, yet recent reports have implicated sex hormones in its development. Nevertheless, the role of hormones from the hypothalamus–hypophysis axis in colitis-associated colorectal cancer (CAC) remains uncertain. In this study, we observed a significant reduction in the expression of the oxytocin receptor (OXTR) in colon samples from both patient with colitis and patient with CAC. To investigate further, we generated mice with an intestinal-epithelium-cell-specific knockout of OXTR. These mice exhibited markedly increased susceptibility to dextran-sulfate-sodium-induced colitis and dextran sulfate sodium/azoxymethane-induced CAC compared to wild-type mice. Our findings indicate that OXTR depletion impaired the inner mucus of the colon epithelium. Mechanistically, oxytocin was found to regulate Mucin 2 maturation through β1-3-N-acetylglucosaminyltransferase 7 (B3GNT7)-mediated fucosylation. Interestingly, we observed a positive correlation between B3GNT7 expression and OXTR expression in human colitis and CAC colon samples. Moreover, the simultaneous activations of OXTR and fucosylation by l-fucose significantly alleviated tumor burden. Hence, our study unveils oxytocin’s promising potential as an affordable and effective therapeutic intervention for individuals affected by colitis and CAC.

Neonicotinoid insecticides (NNIs) are widely used in agriculture, horticulture, forestry, and household environment, but their potential impact on human health remains a subject of concern. This study aimed to investigate the relationship between NNIs and their metabolites in urine with serum lipid profiles in adults using data from the National Health and Nutrition Examination Survey (NHANES) 2015–2016. The study included 1192 participants aged over 20 years with urinary NNIs levels, serum lipid parameter levels and potential confounders. Urinary concentrations of NNIs, including imidacloprid, acetamiprid, clothianidin, thiacloprid, N-desmethyl-acetamiprid, and 5-hydroxy-imidacloprid, were quantified. Serum lipids profiles, such as total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (Apo-B), were assessed. Considering the effects of lipid-lowering medications, the censored normal regression model was used to explore the associations between urinary NNIs and TC, TG, HDL-C, LDL-C and Apo-B levels. The results revealed a significant increase of 9.0 mg/dL (95%CI: 2.0, 16.1) in TC levels among participants with detectable N-desmethyl-acetamiprid compared to those with undetectable levels. Stratified analysis indicated that the association between N-desmethyl-acetamiprid and HDL-C levels was more pronounced among participants aged ≥ 46 years compared to those aged between 20 and 45 years with undetectable N-desmethyl-acetamiprid (pinteraction=0.044). Additionally, there were marginal effect modification of BMI on the association between N-desmethyl-acetamiprid and LDL-C (pinteraction=0.097) and Apo-B (pinteraction=0.052) levels. Specifically, participants with BMI ≥ 25 kg/m² and detectable N-desmethyl-acetamiprid tended to have higher LDL-C and Apo-B levels compared to those with BMI

Spreading depolarization (SD) is a massive wave of cellular depolarization that slowly migrates across the brain gray matter. Cortical SD is frequently generated following brain injury, while less is understood about its potential contribution to genetic disorders of hyperexcitability, such as SCN1A-deficient epilepsy, in which febrile seizure often contributes to disease initiation. Here we report that spontaneous SD waves are predominant EEG abnormalities in the Scn1a-deficient mouse (Scn1a+/R1407X) and undergo sustained intensification following a single hyperthermic seizure. Chronic DC-band EEG recording detected spontaneous SDs, seizures, and seizure-SD complexes in Scn1a+/R1407X mice but not WT littermates. The SD events were infrequent, while a single hyperthermia-induced seizure robustly increased SD frequency over 4-fold during the initial postictal week. This prolonged neurological aftermath could be suppressed by memantine administration. Video, electromyogram, and EEG spectral analysis revealed distinct neurobehavioral patterns; individual seizures were associated with increased motor activities, while SDs were generally associated with immobility. We also identified a stereotypic SD prodrome, detectable over a minute before the onset of the DC potential shift, characterized by increased motor activity and bilateral EEG frequency changes. Our study suggests that cortical SD is a pathological manifestation in SCN1A-deficient epileptic encephalopathy.

Age is a core metric in vertebrate management, and the correct estimation of the age of an individual plays a principal role in comprehending animal behavior, identifying genealogical information, and assessing the potential reproductive capacity of populations. Vertebrates have a vertebral column and a distinct head containing a developed brain; they have played an important role in the study of biological evolution. However, biological age estimations constantly exhibit large deviations due to the diversity of vertebrate taxon species, sample types, and determination methods. To systematically and comprehensively understand age estimation methods in different situations, we classify the degree of damage to vertebrates during sample collection, present the sample types and their applications, list commonly applied methods, present methodological recommendations based on the combination of accuracy and implementability, and, finally, predict future methods for vertebrate age assessments, taking into account the current level of research and requirements. Through comprehensive data gathering and compilation, this work serves as an introduction and summary for those who are eager to catch up on related fields and facilitates the rapid and accurate selection of an evaluation method for researchers engaged in related research. This is essential to promote animal conservation and guide the smooth implementation of conservation management plans.

The “Green Belt and Road Initiative” (GBRI) is China’s international cooperation strategy aimed at expanding international collaborations between China, Asia, and Europe through regional trade, policy dialogue, and cultural exchange in order to promote the achievement of sustainable development goals (SDGs). Identifying the development characteristics and deficiencies of Belt and Road countries is critical to investment and policymaking decisions. Here, we incorporated progress evenness across SDGs based on biodiversity measurements to establish a comprehensive assessment system and evaluated the sustainable development status and trajectory of Belt and Road countries from 2017 to 2021. Our results suggest that, although most countries have experienced progress toward SDGs, disregarding evenness among goals tended to result in the overestimation of the current achievements and ignore regional gaps. Economically developed member countries in the Organization for Economic Co-operation and Development (OECD) were more successful in achieving SDGs, but they also faced development bottlenecks owing to uneven development among the 17 goals, with particular shortcomings in goals related to climate actions. However, many countries with relatively poor economies, mostly in Central and Southeast Asia, performed well on eco-environment-related SDGs. Therefore, complementary collaboration among countries may provide a green development pathway to rapidly promote the achievement of SDGs in the Belt and Road region, which emphasizes the urgency and potential for the GBRI. In essence, while uneven development is a tremendous challenge for Belt and Road countries, it presents an opportunity to enhance regional cooperation in support of the GBRI.

Abstract Background Wild Amur tigers are a sparsely populated species, and the conservation of this species is of great concern worldwide, but as an important health risk factor, parasite infection in them is not fully understanding. Results In this study, sixty-two faecal samples were collected to investigate the frequency and infection intensity of Toxocara cati and Toxascaris leonina in wild Amur tigers. The T. cati and T. leonina eggs were preliminary identified by microscopy, and confirmed by molecular techniques. Infection intensity was determined by the modified McMaster technique. Phylogenetic trees demonstrated that T. cati of wild Amur tiger had a closer relationship with which of other wild felines than that of domestic cats. T. leonina of Amur tiger and other felines clustered into one clade, showing a closer relationship than canines. The average frequency of T. cati was 77.42% (48/62), and the frequency in 2016 (100%) were higher than those in 2013 (P = 0.051,

Traffic infrastructure safety is a core topic in traffic construction and development. As the impact of global climate change becomes more and more significant, extreme weather brings more and more safety issues to the normal operation of subway systems. Therefore, it is an urgent issue in the construction of subway systems to fully prepare for extreme weather and improve system resilience under external disturbances. The resilience of a complex system generally refers to its ability to adapt to external disturbances and return to a functional state. As one of several key infrastructure systems in large cities, a subway system needs to be highly resilient to cope with various risks, and it needs to recover quickly under uncertain weather conditions and other external damage events. In order to achieve the goal of conducting a real-time resilience assessment of a subway system, this study adopts the Bayesian network and the traditional failure mode and effect analysis (FMEA) method to realize resilience assessment with multiple performance indicators. Combined with the risk matrix method from FMEA, multiple important indicators of a subway system under the influence of extreme weather are obtained. These important indicators are integrated into the resilience assessment of the subway system within a Bayesian method. In this paper, the feasibility and applicability of the proposed method are verified by taking the Changping Line of the Beijing subway under extreme rainfall weather (>10 mm) as a case.

Congenital heart disease (CHD) poses a significant global health and economic burden—despite advances in treating CHD reducing the mortality risk, globally CHD accounts for approximately 300,000 deaths yearly. Children with CHD experience both acute and chronic cardiac complications, and though treatment options have improved, some remain extremely invasive. A challenge in addressing these morbidity and mortality risks is that little is known regarding the cause of many CHDs and current evidence suggests a multifactorial etiology. Some studies implicate an immune contribution to CHD development; however, the role of the immune system is not well-understood. Defining the role of the immune and inflammatory responses in CHD therefore holds promise in elucidating mechanisms underlying these disorders and improving upon current diagnostic and treatment options. In this review, we address the current knowledge coinciding CHDs with immune and inflammatory associations, emphasizing conditions where this understanding would provide clinical benefit, and challenges in studying these mechanisms.

Children with acquired heart disease face significant health challenges, including a lifetime of strict medical management, multiple cardiac surgeries, and a high mortality risk. Though the presentation of these conditions is diverse, a unifying factor is the role of immune and inflammatory responses in their development and/or progression. For example, infectious agents have been linked to pediatric cardiovascular disease, leading to a large health burden that disproportionately affects low-income areas. Other implicated mechanisms include antibody targeting of cardiac proteins, infection of cardiac cells, and inflammation-mediated damage to cardiac structures. These changes can alter blood flow patterns, change extracellular matrix composition, and induce cardiac remodeling. Therefore, understanding the relationship between the immune system and cardiovascular disease can inform targeted diagnostic and treatment approaches. In this review, we discuss the current understanding of pediatric immune-associated cardiac diseases, challenges in the field, and areas of research with potential for clinical benefit.

It has been well acknowledged that the gut microbiome is important for host health, composition changes in these microbial communities might increase susceptibility to infections and reduce adaptability to environment. Reintroduction, as an effective strategy for wild population recovery and genetic diversity maintenance for endangered populations, usually takes captive populations as rewilding resource. While, little is known about the compositional and functional differences of gut microbiota between captive and wild populations, especially for large carnivores, like Amur tiger. In this study, high throughput sequencing of the 16S ribosomal RNA (rRNA) gene (amplicon sequencing) and metagenomics were used to analyze the composition and function variations of gut microbiota communities between captive and wild Amur tiger populations based on total 35 fecal samples (13 from captive tigers and 22 from wild tigers). Our results showed that captive Amur tigers have higher alpha diversity in gut microbiota, but that the average unweighted UniFrac distance of bacterial taxa among wild Amur tigers was much larger. The function differences involve most aspects of the body functions, especially for metabolism, environmental information processing, cellular processes, and organismal systems. It was indicated that the diet habit and environment difference between captive and wild populations lead to composition differences of gut microbiota and then resulted in significant differences in functions. These contrasts of functional and compositional variations in gut microbiota between wild and captive Amur tigers are essential insights for guiding conservation management and policy decision-making, and call for more attention on the influence of gut microbiota on the ability of captive animals to survive in the wild.

The ecological threshold concept describes how changes in one or more factors at thresholds can result in a large shift in the state of an ecosystem. This concept focuses attention on limiting factors that affect the tolerance of systems or organisms and changes in them. Accumulating empirical evidence for the existence of ecological thresholds has created favorable conditions for practical application to wildlife conservation. Applying the concept has the potential to enhance conservation of two large carnivores, Amur tiger and leopard, and the knowledge gained could guide the construction of a proposed national park. In this review, ecological thresholds that result from considering a paradigm of bottom-up control were evaluated for their potential to contribute to the conservation of Amur tiger and leopard. Our review highlights that large carnivores, as top predators, are potentially affected by ecological thresholds arising from changes in climate (or weather), habitat, vegetation, prey, competitors, and anthropogenic disturbances. What's more, interactions between factors and context dependence need to be considered in threshold research and conservation practice, because they may amplify the response of ecosystems or organisms to changes in specific drivers. Application of the threshold concept leads to a more thorough evaluation of conservation needs, and could be used to guide future Amur tiger and leopard research and conservation in China. Such application may inform the conservation of other large carnivores worldwide. Keywords: Ecological threshold, Bottom-up effect, Amur tiger and leopard, Large carnivores conservation

Objective: Aortic valve disease is commonly found in the elderly population. It is characterized by dysregulated extracellular matrix remodeling followed by extensive microcalcification of the aortic valve and activation of valve interstitial cells. The mechanism behind these events are largely unknown. Studies have reported expression of hypoxia inducible factor-1 alpha (HIF1α) in calcific nodules in aortic valve disease, therefore we investigated the effect of hypoxia on extracellular matrix remodeling in aged aortic valves.Approach and Results: Western blotting revealed elevated expression of HIF1α and the complex of matrix metalloprotease 9 (MMP9) and neutrophil gelatinase-associated lipocalin (NGAL) in aged porcine aortic valves cultured under hypoxic conditions. Consistently, immunofluorescence staining showed co-expression of MMP9 and NGAL in the fibrosa layer of these porcine hypoxic aortic valves. Gelatinase zymography demonstrated that the activity of MMP9-NGAL complex was significantly increased in aortic valves in 13% O2 compared to 20% O2. Importantly, the presence of ectopic elastic fibers in the fibrosa of hypoxic aortic valves, also detected in human diseased aortic valves, suggests altered elastin homeostasis due to hypoxia.Conclusion: This study demonstrates that hypoxia stimulates pathological extracellular matrix remodeling via expression of NGAL and MMP9 by valve interstitial cells.

Zr2P2WO12 powder was successfully prepared by using hydrothermal method, followed by preparation of Zr2P2WO12/Fe-Ni composites close to the density by using vacuum hot pressing sintering method. The performance and characterization of Zr2P2WO12 and Zr2P2WO12/Fe-Ni composites materials were carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermal expansion analyzer. In addition, the hardness of the composites was tested using Vickers hardness instrument and the density of the as-prepared composites was characterized by using drainage method. The results show that the Zr2P2WO12 powder prepared by hydrothermal method is single-phase of high purity. The grain of Zr2P2WO12 powder is regular and the grain size is about 50nm. With the increase of Zr2P2WO12 percentage, the hardness of Zr2P2WO12/Fe-Ni composites increases, while the density and the relative density decrease. The average thermal expansion coefficient of the as-prepared composites decreases from 13.5×10-6/℃ to 8.6×10-6/℃ with the temperature changing between 25℃ and 800℃.

The Maillard reaction involves a series of complex reactions; fluorescent compounds have been considered as vital intermediate products of the reaction. In this article, carbon dots (CDs) based on the Maillard reaction (MR-CDs) were prepared with L-tryptophan and D-glucose, and they had excellent photoluminescence stability. MR-CDs showed stable pH-dependence behavior and exhibited an excellent linear response to pH in the range of 4.0–7.5 and 7.5–13.0, respectively. Under the masking effect of sodium fluoride for Fe(III), MR-CDs showed excellent selectivity and sensitivity for Cr (VI). The linear range of Cr(VI) was 0.2–50 μM and the limit of detection was 20 nM. (S/N ≥ 3). Furthermore, MR-CDs were used to detect Cr(VI) in tap water samples. The recoveries were between 95.8% and 98.94%, and RSDs were less than 3.17%.

This paper is aimed at crowding phenomenon in the subway. As passengers are inclined to choose the route with minimum disutility, we put forward a route choice model which is constructed to achieve minimum objective function of feasibility for the optimal solution. Meanwhile we set passenger volume threshold values according to capacity of facilities. In the case of actual capacity exceeding the threshold, the decision node of constrained route will be selected; computing procedure about searching decision points will be presented. Then we should set rational restrictions at the decision node of the minimum utility function route to prevent too many passengers’ access to platform. Through certification, this series of methods can effectively ensure the safety of the station efficient operation.