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The surface temperature (Ts) and vegetation index (VI) triangle method is one of the most famous and widely applied methods for regional evapotranspiration (ET) estimation. However, no robust validation has been performed yet to evaluate its accuracy on a global scale, making its accuracy unclear when compared with other global ET models. The main reason behind it is that most traditional triangle models depend on the Ts-VI feature space within a certain spatial domain to parameterize their boundary conditions. The domain dependency makes it impossible to derive universal boundaries for continental or global application. Under this background, this study presented a universal triangle method for ET estimation with Moderate Resolution Imaging Spectroradiometer (MODIS) products and routine meteorological observations. The solution for boundary conditions was performed pixel by pixel without the consideration of spatial domain based configuration. Specifically, the dry boundary was solved theoretically based on the surface energy balance equation, and the wet boundary was substituted by wet-bulb temperature estimated from dew point temperature and air temperature. The validation against ground observations collected from 33 flux towers worldwide shows that this universal triangle method achieved evaporative fraction (EF) estimation with the correlation coefficient of 0.65, the mean absolute error of 0.17, the root-mean-square-error of 0.20, and the bias of 0.13. These four metrics of daily ET estimation were 0.83, 0.71 mm/d, 0.90 mm/d, and 0.41 mm/d, respectively. This analysis is the first comprehensive validation of the triangle method on a global scale. The comparison with early work suggests that our universal triangle method on a global scale has reached a comparable accuracy to traditional triangle models at regional scale. However, the universal triangle method has the capacity to monitor ET continuously pixel by pixel without domain dependency. This is just what most traditional triangle methods do not possess.

The two-spotted spider mite, Tetranychus urticae Koch, is one of the most harmful pests in many agroecosystems worldwide. To effectively manage this pest, there is an urgent need to develop novel bio-active acaricides that support integrated pest management strategies targeting T. urticae. In this study, we explored the acaricidal effects of xenocoumacin 1 (Xcn1) on T. urticae and its predator Neoseiulus californicus using the highly purified compound. Xcn1 was extracted and purified from the cell-free supernatant of the Xenorhabdus nematophila CB6 mutant constructed by the easy promoter activated compound identification (easyPACId) method. When the concentration of Xcn1 exceeded 100 μg mL−1, the survival rate of spider mite adults declined to below 40% and the fecundity was decreased by 80% at six days post-application. At concentrations of 25 and 50 μg mL−1, Xcn1 significantly impeded spider mite development by inhibiting the molt. However, neither concentration had any adverse effects on the survival or reproduction of the predatory mite N. californicus. The results from laboratory and semi-field experiments consistently demonstrated the effectiveness of the antimicrobial metabolite Xcn1 in controlling pest mites at both the molecular and physiological levels. Our study offers a promising possibility that combines the compatible biocontrol agents of Xcn1 and predatory mites for integrated pest mite control.

Summary: Background: Dietary restriction (DR), a general term for dieting, has been demonstrated as an effective intervention in reducing the occurrence of cancers. Molecular activities associated with DR are crucial in mediating its anti-cancer effects, yet a comprehensive exploration of the landscape of these activities at the pan-cancer level is still lacking. Methods: We proposed a computational approach for quantifying DR-related molecular activities and delineating the landscape of these activities across 33 cancer types and 30 normal tissues within 27,320 samples. We thoroughly examined the associations between DR-related molecular activities and various factors, including the tumour microenvironment, immunological phenotypes, genomic features, and clinical prognosis. Meanwhile, we identified two DR genes that show potential as prognostic predictors in hepatocellular carcinoma and verified them by immunohistochemical assays in 90 patients. Findings: We found that DR-related molecular activities showed a close association with tumour immunity and hold potential for predicting immunotherapy responses in various cancers. Importantly, a higher level of DR-related molecular activities is associated with improved overall survival and cancer-specific survival. FZD1 and G6PD are two DR genes that serve as biomarkers for predicting the prognosis of patients with hepatocellular carcinoma. Interpretation: This study presents a robust link between DR-related molecular activities and tumour immunity across multiple cancer types. Our research could open the path for further investigation of DR-related molecular processes in cancer treatment. Funding: National Natural Science Foundation of China (Grant No. 82000628) and the Guangdong-Hong Kong-Macao University Joint Laboratory of Interventional Medicine Foundation of Guangdong Province (Grant No. 2023LSYS001).

Rapid urbanization and people's growing spiritual demand make urban spaces face the problem of green space allocation, especially the mismatch between the supply and demand of cultural ecosystem services (CES). The matching degree of supply and demand of CESs is significantly related to the well-being of urban residents. However, few existing studies have compared the supply and demand of CES from the perspective of old and new urban districts. This study constructed a theoretical framework oriented to four functions (aesthetic appreciation, recreation and leisure, educational opportunities, history and culture) based on subjective and objective evaluation and spatial autocorrelation analysis in order to map the supply–demand matching pattern of CES in urban parks at the community scale. The Qinhuai district of Nanjing, where the division between old and new urban districts is relatively obvious, is used as the study area to explore the influence of old and new urban districts on the supply–demand balance. Results showed that: (1) the CES supply in urban parks had high spatial agglomeration characteristics, and the service supply capacity decreased radially centered on large and medium-sized comprehensive parks; (2) the CES demand took on an obvious trend of gradual decrease from the northwest to the southeast, with obvious spatial heterogeneity; (3) mismatches were found between service supply and demand at the community scale, the overall matching degree in new urban districts was better than in old urban districts. These findings can provide a valuable exploration for optimizing urban park configuration and improving service efficiency under the background of stock planning.

Accurate estimation of terrestrial evapotranspiration (ET) is crucial to understand the water cycle and partitioning of turbulent energy fluxes at the land surface. However, large-scale ET estimation is always difficult to achieve due to the complexity of controlling factors and the heterogeneity of landscapes. A recent model, referred to as the surface flux equilibrium (SFE) model, proposes that evaporative fraction (EF, the ratio of ET to available energy at the surface) can be estimated accurately from near-surface specific humidity and air temperature, which makes it applicable to common weather stations and climate reanalysis datasets. However, previous validation only focused on the evaluation of this model at site and basin scale for ET estimation, making the real performance of the SFE model for EF estimation heretofore unknown. There also exists a gap in the comparison between the SFE model and other existing products in the representation of global ET patterns and variation trend. Against this background, a comprehensive validation was performed in this study to evaluate the accuracy of the SFE model for both EF and ET estimation. The validation against 136 flux towers worldwide shows that the ground-based SFE model achieved EF estimation with a root-mean-square-error (RMSE) of 0.22 and 0.16 at daily and monthly scale, respectively. The corresponding RMSE of ET estimation was 0.94 mm/day and 16.37 mm/month. The application of the SFE model on a global scale was achieved by using two reanalysis products (ERA5-Land and GLDAS-CLSM) as inputs respectively. The results indicate that the SFE model did hold potential to reduce the RMSE of these two products for ET estimation, but the cost was the decrease in correlation coefficient (r). The comparison with five existing global ET products (BESS, GLEAM, AVHRR, MOD16, and SSEBop) shows that the SFE model performed on the basis of ERA5-Land product has achieved moderate accuracy among these products. Judged from r, mean absolute error, RMSE, and bias, its accuracy was ranked as fourth, fourth, second, and second, respectively. However, a further evaluation over different land cover types suggests that the ERA-based SFE model has significant superiority over cropland, relative superiority over forest and savannas, and significant inferiority over shrubland and grassland. This analysis is the first global validation of the SFE model for EF estimation as well as its comparison with existing global ET products. The validation analysis proves that this simple model has generally achieved comparable accuracy to existing complex models in the representation of global ET patterns and variation trend.

Accurate estimation of surface evapotranspiration (ET) in the Heihe River Basin using remote sensing data is crucial for understanding water dynamics in arid regions. In this paper, by coupling physical constraints and machine learning for hybrid modeling, we develop a hybrid model based on surface conductance optimization. A hybrid modeling algorithm, two physical process-based ET algorithms (Penman–Monteith-based and Priestley–Taylor-based ET algorithms), and three pure machine learning algorithms (Random Forest, Extreme Gradient Boosting, and K Nearest Neighbors) are comparatively analyzed for estimating the ET. The results showed that, in general, the machine learning model optimized by parameters was able to better predict the surface conductance of the hybrid model. Driver analyses showed that radiation, normalized difference vegetation index (NDVI), and air temperature had high correlations with ET. The hybrid model had a better prediction performance for ET than the other five models, and it improved the R2 of the two physical process-based algorithms to 0.9, reduced the root mean square error (RMSE) to 0.5 mm/day, reduced the BIAS to 0.2 mm/day, and improved the Kling–Gupta efficiency (KGE) to 0.9. The hybrid model outperformed the others across different time scales, displaying lower BIAS, RMSE, and higher KGE. Spatially, its ET patterns aligned with regional vegetation changes, with superior accuracy in annual ET estimation compared to the other models. Comparison with other ET products shows that the estimation results based on the hybrid model have better performance. This approach not only improves the accuracy of ET estimation but also improves the understanding of the physical mechanism of ET estimation by pure machine learning models. This study can provide important support for understanding ET and hydrological processes under different climatic and biotic vegetation in other arid and semi-arid regions.

High spatial resolution maps of evapotranspiration (ET) for precision agricultural irrigation, water resource management are increasingly important in the context of climate change. Here, we conducted extensive unmanned aerial vehicle (UAV) experiments in oasis-desert areas with three 2 km × 1 km regions during two growing seasons. The spatially distributed land surface temperature (LST), albedo and leaf area index (LAI) were retrieved from thermal infrared, multispectral and LiDAR (light detection and ranging) multi-sensor data, and the surface energy balance system (SEBS) model with an optimized surface roughness length for heat transfer was utilized to estimate ET with a super high resolution (SHR) of 0.2 m. The model’s outputs were validated using the measurements from the eddy covariance (EC) with a source area of hundred meters and optical-microwave scintillometer (OMS) with a source area of approximately 2 km × 1 km. They yielded mean root mean square error (RMSE) values of 53 and 45 W/m2 for sensible heat flux (H) and 70 and 65 W/m2 for latent heat flux (LE), respectively. The seasonal characteristics of LE distributions indicated the difference of LE in oasis-desert areas varied with the growing period. These sub-pixel differences in the cropland, wetland, and desert experimental areas were caused mainly by the agricultural activities, the vegetation coverage, and the topographic peaks and valleys, respectively. This study can potentially provide spatially sub-pixel information on agricultural and ecological water management and genuinely bridge the spatio-temporal scale gap between field observations and satellite remote sensing.

Green infrastructure (GI) conservation is essential for maintaining ecosystem services, and has become one of the key questions in landscape ecological research, especially within urban agglomerations. However, the effectiveness of different GI conservation scenarios on land use change and landscape connectivity have rarely been explored in urban environments. Therefore, this study developed a framework that integrates GI conservation into scenario design to simulate the land use patterns and landscape connectivity of the Southern Jiangsu (SJ) urban agglomeration in 2030. Four GI conservation scenarios, which includes business as usual (BAU), source conservation (SCS), corridor conservation (CCS), and integrated source and corridor conservation (ISCCS), were constructed and compared with the year 2020 as the baseline. We found that the areas of forest, grassland and water body were decreased remarkably under the BAU. The SCS mainly mitigated the reduction of forest area, while the CCS mostly contributed to the conservation of water body and grassland. The ISCCS resulted in a slight decrease of forest area but increases in water body and grassland. Moreover, the ISCCS had the best performance in the improvement of landscape connectivity, followed by the CCS and the SCS. Our analysis reveals that the multiple GI conservation scenarios effectively protected the area and landscape connectivity of natural spaces, with different extent of contribution and beneficial objectives. Our study can help urban planners understand how natural spaces will be disturbed over time and provide a reference for natural resources regulation and ecological conservation actions.

Study region: The Yellow River Basin plays a crucial role in China's socio-economic development and ecological security. Study focus: The growing trend of water consumption driven by anthropogenic activities has posed an increasing number of challenges for the sustainable development of the Yellow River basin. Water demand prediction plays a central part in facilitating water conservation by developing water allocation strategies. Hence, the water demand prediction model based on the concept of water resources carrying capacity was built to predict water demand with different future scenarios and provide reference strategies for water allocation. New hydrological insights for the region: With all changing scenarios under consideration, the future demand for water resources will significantly increase compared with the current conditions. The range of water demand by each province along the Yellow River basin is exhibited in this study. Two scenarios with different economic development conditions and cascading water use efficiency are investigated. In addition, solutions for improving water use efficiency and increasing the available quantity of water are put forward to ameliorate water stress. Specifically, water distribution schemes with a medium level of water use efficiency in different economic growth scenarios are proposed based on the available water resources from the Yellow River basin and the South-to-North Water Diversion Project. This work will benefit local planners and decision-makers.

In the past decades, rapid urbanization in China has dramatically transformed natural spaces into construction land, leading to serious degradation and supply–demand imbalance of ecosystem services (ESs). The identification of critical areas and ecological security patterns is crucial for balancing ESs and improving human well-being in rapidly urbanized regions. The purpose of this study was to establish a comprehensive assessment framework of ES supply–demand including provisioning, regulating, supporting, and cultural services, so as to provide theoretical support for the identification and refined management of regional critical areas. Taking a typical waterside area in Shanghai metropolitan area as an example, based on multi-source data and ES quantitative models, we used ecological supply–demand ratio and bivariate local indicators of spatial association to quantify the relationship and matching patterns of ES supply–demand, then explored the identification, protection, and restoration of ecologically critical areas at the regional scale. The results showed that: 1) the ES supply–demand relationship in the study area was quantitatively determined. The ecological supply–demand ratio was as follows: regulating > provisioning > supporting > cultural, in which the supply of supporting and cultural services was less than the demand, and the problem of the supply–demand mismatch is prominent; 2) we have identified 41 supply critical areas that require priority protection, with a total area of 206.79 km2 accounting for 9.65% of the total study area, showing a spatial pattern of more in the northwest and less in the southeast; 3) a total of 11 demand critical areas that need ecological restoration were identified, accounting for 31.43% of the 35 administrative towns in the study area, which are mainly distributed around three urban centers and a high-tech zone. The study is of great significance for the construction of regional ecological security patterns and rational ES allocation, and can provide a scientific framework for the ecological protection and restoration of critical areas around metropolises in developing countries.

Graph summarization techniques are vital in simplifying and extracting enormous quantities of graph data. Traditional static graph structure-based summarization algorithms generally follow a minimum description length (MDL) style, and concentrate on minimizing the graph storage overhead. However, these methods also suffer from incomprehensive summary dimensions and inefficiency problems. In addition, the need for graph summarization techniques often varies among different graph applications, but an ideal summary method should generally retain the important characteristics of the key nodes in the final summary graph. This paper proposes a novel method based on ranking nodes, called HRNS, that follows a hierarchical parallel graph summarization approach. The HRNS first preprocesses the node ranking using a hybrid weighted importance strategy, and introduces the node importance factor into traditional MDL-based summarization algorithms; it then leverages a hierarchical parallel process to accelerate the summary computation. The experimental results obtained using both real and simulated datasets show that HRNS can efficiently extract nodes with high importance, and that the average importance over six datasets ranges from 0.107 to 0.167; thus, HRNS can achieve a significant performance gain on speedups, as the sum error ratios are also lower than the methods traditionally used.

ObjectiveTo investigate the expression level of miR-4739 in gastric cancer (GC), analyze its diagnostic value in GC and the relationship with clinical pathological characteristics, and analyze its impact on the prognosis of patients.MethodsA total of 96 patients with GC who underwent radical gastrectomy in our hospital from March 2017 to June 2021 were selected. GC tissues from all patients were collected, and normal tissues adjacent to cancer were collected as controls. The expression level of miR-4739 in tissues was detected, the relationship between miR-4739 and different pathological features was analyzed, and the diagnostic value of miR-4739 in GC was analyzed. All patients were followed up after the operation, and the survival time of the patients was set as from the day of the first operation to 1 d when the patients died or the follow-up ended.ResultsThe relative expression level of miR-4739 in the GC tissue was (0.39 ± 0.06), lower than that in the paracancerous tissue (1.18 ± 0.19) (P

The L-type amino acid transporter (LAT) family contains four members, LAT1~4, which are important amino acid transporters. They mainly transport specific amino acids through cell membranes, provide nutrients to cells, and are involved in a variety of metabolic pathways. They regulate the mTOR signaling pathway which has been found to be strongly linked to cancer in recent years. However, in the field of prostate cancer (PCa), the LAT family is still in the nascent stage of research, and the importance of LATs in the diagnosis and treatment of prostate cancer is still unknown. Therefore, this article aims to report the role of LATs in prostate cancer and their clinical significance and application. LATs promote the progression of prostate cancer by increasing amino acid uptake, activating the mammalian target of rapamycin (mTOR) pathway and downstream signals, mediating castration-resistance, promoting tumor angiogenesis, and enhancing chemotherapy resistance. The importance of LATs as diagnostic and therapeutic targets for prostate cancer was emphasized and the latest research results were introduced. In addition, we introduced selective LAT1 inhibitors, including JPH203 and OKY034, which showed excellent inhibitory effects on the proliferation of various tumor cells. This is the future direction of amino acid transporter targeting therapy drugs.

Graves ophthalmopathy (GO), a manifestation of Graves’ disease, is an organ-specific autoimmune disease. Intravenous glucocorticoid therapy (ivGCs) is the first-line treatment for moderate-to-severe and active GO. However, ivGCs is only effective in 70%–80% of GO patients. Insensitive patients who choose 12-week ivGCs not only were delayed in treatment but also took the risk of adverse reactions of glucocorticoids. At present, there is still a lack of effective indicators to predict the therapeutic effect of ivGCs. Therefore, the purpose of this study is to find biomarkers that can determine the sensitivity of ivGCs before the formulation of treatment, and to clarify the mechanism of its regulation of ivGCs sensitivity. This study first characterized the miRNA profiles of plasma exosomes by miRNA sequencing to identify miRNAs differentially expressed between GO patients with significant improvement (SI) and non-significant improvement (NSI) after ivGCs treatment. Subsequently, we analyzed the function of the predicted target genes of differential miRNAs. According to the function of the target genes, we screened 10 differentially expressed miRNAs. An expanded cohort verification showed that compared with NSI patients, mir-885-3p was upregulated and mir-4474-3p and mir-615-3p were downregulated in the exosomes of SI patients. Based on statistical difference and miRNA function, mir-885-3p was selected for follow-up study. The in vitro functional analysis of exosomes mir-885-3p showed that exosomes from SI patients (SI-exo) could transfer mir-885-3p to orbital fibroblasts (OFs), upregulate the GRE luciferase reporter gene plasmid activity and the level of glucocorticoid receptor (GR), downregulate the level of inflammatory factors, and improve the glucocorticoid sensitivity of OFs. Moreover, these effects can be inhibited by the corresponding miR inhibitor. In addition, we found that high levels of mir-885-3p could inhibit the AKT/NFκB signaling pathway, upregulate the GRE plasmid activity and GR level, and downregulate the level of inflammatory factors of OFs. Moreover, the improvement of glucocorticoid sensitivity by mir-885-3p transmitted by SI-exo can also be inhibited by the AKT/NFκB agonist. Finally, through the in vivo experiment of the GO mouse model, we further determined the relationship between exosomes’ mir-885-3p sequence, AKT/NFκB signaling pathway, and glucocorticoid sensitivity. As a conclusion, plasma exosomes deliver mir-885-3p and inhibit the AKT/NFκB signaling pathway to improve the glucocorticoid sensitivity of OFs. Exosome mir-885-3p can be used as a biomarker to determine the sensitivity of ivGCs in GO patients.

Heart failure (HF) is a globally prevalent cardiovascular disease, but effective drug targets and diagnostic models are still lacking. This study was designed to investigate effective drug targets and diagnostic models for HF in terms of miRNA targets, hoping to contribute to the understanding and treatment of HF. Using HF miRNA and gene expression profile data from the GEO database, we analyzed differentially expressed miRNAs/gene identification in HF using Limma and predicted miRNA targets by the online TargetScan database. Subsequently, gene set enrichment analysis and annotation were performed using WebGestaltR package. Protein-protein interactions were identified using the STRING database. The proximity of drugs to treat HF was also calculated and predicted for potential target therapeutic drug. In addition, further drug identification was performed by molecular docking. Finally, diagnostic models were constructed based on differential miRNAs. The GEO dataset was used to screen 66 differentially expressed miRNAs, incorporating 56 downregulated miRNAs and 10 upregulated miRNAs. The JAK-STAT signaling pathway, MAPK signaling pathway, p53 signaling pathway, Prolactin signaling pathway, and TGF-beta signaling pathway were enriched, as shown by KEGG enrichment analysis on the target genes. In addition, we found that 83 genes were upregulated and 92 genes were downregulated in HF patients vs. healthy individuals. Based on the inflammation-related score, hypoxia-related score, and energy metabolism-related score, we identified key miRNA-mRNA pairs and constructed an interaction network. Following that, TAP1, which had the highest expression and network connectivity in acute HF with crystal and molecular docking studies, was selected as a key candidate gene in the network. And the compound DB04847 was selected to produce a large number of favorable interactions with TAP1 protein. Finally, we constructed two diagnostic models based on the differential miRNAs hsa-miR-6785-5p and hsa-miR-4443. In conclusion, we identified TAP1, a key candidate gene in the diagnosis and treatment of HF, and determined that compound DB04847 is highly likely to be a potential inhibitor of TAP1. The TAP1 gene was also found to be regulated by hsa-miR-6785-5p and hsa-miR-4443, and a diagnostic model was constructed. This provides a new promising direction to improve the diagnosis, prognosis, and treatment outcome and guide more effective immunotherapy strategies of HF.

With abundant resources in the wetland, the Yellow River Delta provides important habitats for various kinds of rare bird species. However, due to climate change and human water withdrawal activities, no-flow events of the Yellow River occurred frequently since the 1970s, resulting in serious wetland degradation and biodiversity losses. Ecological water supplement has been regarded as one of the most effective measures to cope with these environmental problems. Accordingly, how much water is required for the ecological restoration becomes an essential question to be answered. Since the primary function of the Yellow River Delta Natural Reserve (YRDNR), the typical wetland in the Yellow River Delta, is to provide suitable habitats for various rare birds, the purpose of this paper is to propose a method based on water balance analysis to specify monthly ecological water supplement for the habitats of typical birds in the YRDNR. Specifically, three typical birds were selected as the protection objects, including Grus japonensis, Ciconia boyciana, and Larus saundersi. Monthly water supplement was determined by monthly long-term time series data (2003–2018) of evapotranspiration product derived from remote sensing and meteorological data (precipitation and pan evaporation) acquired from National Meteorological Information Center. The results showed that the annual ecological water supplement for 10 km2 ideal habitats was 666.17×104 m3, 1165.22×104 m3, and 664.48×104 m3 for G. japonensis, C. boyciana, and L. saundersi, respectively. Besides, it was found that annual precipitation generally had a significant negative relation with annual ecological water supplement, which suggested that local precipitation should be considered as a key factor in determining the amount of annual water supplement. The frequency analysis was then implemented to provide reasonable scheme of actual ecological water supplement under different precipitation scenarios. The results indicated that annual ecological water supplement for the whole YRDNR was 1.81×108 m3, 1.94×108 m3, 2.10×108 m3 and 2.25×108 m3 respectively under wet, average, dry and extreme dry conditions. If water storage measurements are implemented to store surplus precipitation under rainy season, the average volume would reduce by nearly 10%.

A large number of trees have been planted in built-up areas to improve the urban environment, but the effects of tree cover on spontaneous understory herbs are not yet well understood. This study surveyed spontaneous herbs in two kinds of habitats (habitats with and without tree cover) in the built-up area of the small city Junlian in Sichuan Province, China. A total of 222 species of spontaneous herbaceous plants in 180 genera of 71 families were recorded, including a vulnerable species and six species endemic to China. Although the overall species richness values were similar in the two kinds of habitat, the average species richness per quadrat of all plants, perennials, plants with the dwarf growth form, and animal-dispersed plants was significantly higher in the habitats with tree cover than in those without tree cover. The overall species association was significantly positive in the habitats with tree cover (VR = 1.51, p < 0.05) and neural (VR = 0.86) in the habitats without tree cover. Among the top 25 frequently recorded species in each kind of habitat, the species association of plants with the same trait combination type differed greatly in the two kinds of habitats. For the species association between annuals, only 13.33% of species pairs were significantly associated in the habitats with tree cover, while 22.22% of the species pairs were significantly negatively associated in the habitats without tree cover. For the species association between plants with tall growth forms, the proportion of significant positive associations in the habitats with tree cover was approximately twice than in the habitats without tree cover. For the species association between plants with the dwarf growth form, the proportion of negative associations in the habitats without tree cover was approximately twice that in the habitats with tree cover. Species with the same dispersal mode generally had a very low proportion of negative interspecific associations or a high proportion of positive interspecific associations in habitats unfavorable to their establishment. Our findings suggest that tree cover can improve the species richness of the spontaneous herbaceous species beneath them and profoundly influence interspecific coexistence relationships in a built-up area.

Diabetes mellitus impairs fracture healing and function of stem cells related to bone regeneration; thus, effective bone tissue engineering therapies can intervene with those dysfunctions. Nanohydroxyapatite/polyamide 66 (n-HA/PA66) scaffold has been used in fracture healing, whereas the low bioactivity limits its further application. Herein, we developed a novel bone morphogenetic protein-2- (BMP-2) and vascular endothelial growth factor- (VEGF) derived peptides-decorated n-HA/PA66 (BVHP66) scaffold for diabetic fracture. The n-HA/PA66 scaffold was functionalized by covalent grafting of BMP-2 and VEGF peptides to construct a dual peptide sustained-release system. The structural characteristics and peptide release profiles of BVHP66 scaffold were tested by scanning electron microscopy, Fourier transform infrared spectroscopy, and fluorescence microscope. Under high glucose (HG) condition, the effect of BVHP66 scaffold on rat bone marrow mesenchymal stem cells’ (rBMSCs) adherent, proliferative, and differentiate capacities and human umbilical vein endothelial cells’ (HUVECs) proliferative and tube formation capacities was assessed. Finally, the BVHP66 scaffold was applied to fracture of diabetic rats, and its effect on osteogenesis and angiogenesis was evaluated. In vitro, the peptide loaded on the BVHP66 scaffold was in a sustained-release mode of 14 days. The BVHP66 scaffold significantly promoted rBMSCs’ and HUVECs’ proliferation and improved osteogenic differentiation of rBMSCs and tube formation of HUVECs in HG environment. In vivo, the BVHP66 scaffold enhanced osteogenesis and angiogenesis, rescuing the poor fracture healing in diabetic rats. Comparing with single peptide modification, the dual peptide-modified scaffold had a synergetic effect on bone regeneration in vivo. Overall, this study reported a novel BVHP66 scaffold with excellent biocompatibility and bioactive property and its application in diabetic fracture.

The variations in the degradation of electrical characteristics resulting from different device structures for trench-gate SiC metal-oxide-semiconductor field effect transistors (MOSFETs) are investigated in this work. Two types of the most advanced commercial trench products, which are the asymmetric trench SiC MOSFET and the double-trench SiC MOSFET, are chosen as the targeted devices. The discrepant degradation trends caused by the repetitive avalanche stress are monitored. For the double-trench device, the conduction characteristic improves while the gate-drain capacitance (Cgd) increases seriously. It is because positive charges are injected into the bottom gate oxide during the avalanche process, which are driven by the high oxide electronic field (Eox) and the high impact ionization rate (I.I.) there. Meanwhile, for the asymmetric trench SiC MOSFET, the I–V curve under the high gate bias condition and the Cgd remain relatively stable, while the trench bottom is well protected by the deep P+ well. However, it’s threshold voltage (Vth) decreases more obviously when compared with that of the double-trench device and the inclined channel suffers from more serious stress than the vertical channel. Positive charges are more easily injected into the inclined channel. The phenomena and the corresponding mechanisms are analyzed and proved by experiments and technology computer-aided design (TCAD) simulations.

Abstract Background College students in China are emerging as one of the most vulnerable groups to contract HIV, because they are in a sexually active age group and also because of their open attitude toward sex and high risk sexual behaviors. This study aimed to explore the prevalence of willingness among college students to utilize HIV testing and counseling (HTC) service and the factors that may affect willingness, including predisposing, enabling and need factors, based on the Andersen’s behavioral model. Methods A cross-sectional study was conducted from October 6, 2016 to December 31, 2016 in Hubei University of Science and Technology in China. After signing informed consent, college students completed a self-designed online questionnaire distributed via https://www.wjx.cn/ voluntarily, anonymously and confidentially. Pearson’s chi-square test and Logistic regression models were chosen to analyze the factors associated with willingness to utilize HTC service. Results Out of 3314 college students in the sample, 2583 (77.9%) expressed their willingness to utilize HTC service. After adjustment, those with low levels of discrimination towards people living with HIV (PLHIV) (OR = 1.41, 95%CI:1.17–1.68), being more knowledgeable about free HTC service centers (OR = 1.44, 95%CI:1.17–1.77), having recognized the necessity to provide HTC service in the local university (OR = 2.20, 95%CI:1.73–2.80), and having a higher HIV risk perception (OR = 1.64, 95%CI:1.37–1.95) were more willing to utilize HTC service, compared with their respective counterparts. Conclusions In order to improve their willingness to utilize HTC service and finally to achieve the goal of zero-AIDS, a comprehensive intervention measure should be taken to publicize HTC service, eliminate stigma and discrimination against PLHIV, recruit and train peer volunteers to serve in the local university, and increase self-perceived risk of HIV infection.

The loss and fragmentation of natural space has placed tremendous pressure on green infrastructure (GI), especially in urban agglomeration areas. It is of great importance to identify key sites of GI, which are used to economically and efficiently restore urban ecological network. However, in the existing research, few scholars have explored the identification and application of GI key sites. Taking the Southern Jiangsu Urban Agglomeration as an example, based on the ecosystem service assessment and landscape connectivity analysis, we identified the multi-class key sites of GI in the study area by MSPA, InVEST model, MCR model, and Linkage mapper. The results showed that: (1) a total of 60 GI sources and 130 GI corridors were extracted. The ecological resources of the study area were densely distributed in the north and south and sparsely in the middle. (2) Three-hundred eighty GI key sites were identified, including 53 water ecological points, 251 ecological fracture points, and 76 ecological pinch points. The GI key sites we identified were large in number and widely distributed, yet were hardly included in the existing ecological protection policies. These key sites should be prioritized in GI planning and differentiated for management strategies, ensuring that limited land resources and public funds can be directed to where restoration is really needed. The present study provides land managers and urban planners with additional tools to better understand how to effectively restore and develop the ecosystems of urban agglomerations in the context of scarce land resources.

The cooling and humidifying effects of urban aggregated green infrastructure can provide essential services for city ecosystems, regulating microclimates or mitigating the urban heat island effect. However, the optimal thresholds of plant community structure parameters for maximizing the associated cooling and humidifying effects remain unclear. In this paper, we use the method of dummy variable regression to measure plant communities in an urban aggregated green infrastructure. By examining the relationships between the cooling and humidifying effects and plant community structure parameters (i.e., canopy density, porosity, and vegetation type), we introduce optimal thresholds for the parameters. We find that canopy density has a significantly positive correlation with both cooling and humidifying effects, while porosity has a positive correlation with cooling and a negative one with humidifying. Different vegetation types have distinct influences on cooling and humidifying effects. When the canopy density is between 0.81 and 0.85 and the porosity is between 0.31 and 0.35, the cooling and humidifying effects of the plant communities reach their peak. Additionally, the greening coverage rate and spatial types of urban aggregated green infrastructure have influences on cooling and humidifying effects. The findings can help us to better understand the relationships between plant community structure parameters and their temperature regulation functioning for urban aggregated green infrastructure. This study provides guidelines and theoretical references for the plant configuration of future urban green spaces.