•A novel approach to flood risk assessment based on random forest (RF).•The approach can be used to estimate the contribution of each risk index.•Proposed approach is shown to be effective by a case ...study.
Floods, natural disasters that occur worldwide, have become more and more frequent in recent decades. Flooding is often unavoidable and unexpected; however, it can be controlled through appropriate measures to minimize losses and damage. Flood hazard risk assessment, a holistic approach that involves numerous evaluation indices in river catchments, is an increasingly effective and sustainable practice, but the complicated, non-linear relationship between evaluation indices and risk levels pose a significant challenge to accurate assessment. An intelligent learning machine called random forest (RF) can run efficiently on large databases and provide estimates regarding the importance of specific variables in the classification. This lends RF a considerable advantage in solving the non-linear problems inherent to risk assessment, as well as estimating the importance degree of each index. As such, in this study, an assessment model based on RF was adopted to evaluate regional flood hazard risk. The proposed flood hazard risk assessment method was implemented in Dongjiang River Basin, China. Eleven risk indices were selected and five thousand samples were created for training and testing. The support vector machine (SVM) was used for risk assessment as a comparison, as well as an analysis of index importance degree. Results show that (1) both the training and testing error rate of RF can be reduced by increasing the sample size and the number of classification trees, (2) the higher and highest-risk zones occupy approximately 19.09% of the total, and are primarily located in Baoan, Longgang, Huiyang, Huidong, the western area of Boluo, and the southern part of Dongguang, and (3) the indices maximum three-day precipitation (M3PD), runoff depth (RD), typhoon frequency (TF), digital elevation model (DEM), and topographic wetness index (TWI) are the top five most important out of the eleven risk indices, occupying 71.11% of the total risk; but normalized difference vegetation index (NDVI), stream power index (SPI), soil texture (ST), distance to the river (DR), slope (SL), and land use pattern (LUP) indices are less consequential, at only 28.89%. This study shows the potential to provide a novel and highly successful approach to flood hazard risk assessment. Evaluation results provide a reference for flood risk management, prevention, and reduction of natural disasters in the study basin.
To optimize the management of non-point source (NPS) pollution in a changing environment, the cellular automata (CA) and Hydrological Simulation Program-Fortran (HSPF) models were used to study the ...response mechanism of NPS pollution loads to land use change and different precipitation scenarios. Taking the Dongjiang River Basin as a case study, the land use situation and its spatial distribution patterns in 2020, 2030 and 2050 were predicted by the logistic regression-based CA model. The trends of the NPS pollution loads under different land use and precipitation scenarios were quantitatively evaluated. The results show that the total accuracy of the land use change simulated by the CA model was 81%. Both the HSPF model and the CA model were highly applicable to this basin. Precipitation is proven to be the main driving force of NPS pollution. From 2020 to 2050, the annual load, average monthly load, maximum and minimum monthly load of the BOD and TP show an upward trend. TN shows a slight downward trend, which is related to the reduction in cultivated land area and the use of nitrogen fertilizer. In view of the future trend of NPS pollution, the basin should continue to control TN pollution and focus on strengthening BOD and TP control to achieve high-quality management of the water environment.
MicroRNA-130b (miR-130b) downregulation has been identified in diabetes, but the role and mechanisms for miR-130b in mediating renal tubulointerstitial fibrosis in diabetic nephropathy (DN) remain ...unknown. We demonstrated that plasma miR-130b downregulation exhibited clinical and biological relevance as it was linked to increased serum creatinine, β2-microglobulin and proteinuria, increased Snail expression and tubulointerstitial fibrosis in renal biopsies of DN patients. MiR-130b inhibitor caused Snail upregulation and enhanced molecular features of epithelial-to-mesenchymal transition (EMT) in high glucose (30 mM) cultured NRK-52E cells. In contrast, miR-130b mimic downregulated Snail expression and increased epithelial hallmarks. Notably, Snail was identified as an miR-130b direct target and inversely correlated with E-CADHERIN expression. Furthermore, the miR-130b-dependent effects were due to Snail suppression that in turn deregulated E-CADHERIN, VIMENTIN, COLLAGEN IV and α-smooth muscle actin (α-SMA), key mediators of EMT. These effects were reproduced in streptozotocin-induced diabetic rats. Thus, we propose a novel role of the miR-130b-SNAIL axis in fostering EMT and progression toward increased tubulointerstitial fibrosis in DN. Detection of plasma miR-130b and its association with SNAIL can be extrapolated to quantifying the severity of renal tubulointerstitial fibrosis. Targeting miR-130b could be evaluated as a potential therapeutic approach for DN.
Land use and land cover change induced by large scale ecological restoration programs has a significant impact on the terrestrial ecosystem carbon cycle, especially on the net primary productivity ...(NPP) in arid and semi-arid regions. This study investigated the change in NPP caused by the large-scale ecological restoration in the Chinese Loess Plateau (LPR) region from 1986 to 2015 based on land cover datasets and NPP calculated using the Carnegie-Ames-Stanford Approach model. The results indicated that the annual total NPP exhibited a significant uptrend (P < 0.01) throughout the whole vegetation restoration region during the last 30 years, with an annual increase of 0.137 Tg C. A significant abrupt change was detected in 2006 for the annual total NPP series. Over half of the restoration region showed an increase in NPP in the past three decades, however, about 30~40% of the vegetation restoration region exhibited NPP loss before 2006, but subsequently NPP loss was found in only approximately 20% of the study region. Overall, the increase in NPP attributed to the vegetation restoration reached 51.14 Tg C in the past three decades, indicating that these large-scale vegetation restoration programs increased the carbon sequestration capacity of terrestrial ecosystems in the Loess Plateau. The findings of this study improve our understanding of the effects of the green campaign on terrestrial ecosystems.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Highlights • EZH2, as an independent prognostic factor, correlates positively with VEGF-A. • EZH2 overexpression confers a shorter overall survival time in NSCLC patients. • EZH2 stimulates ...VEGF-A expression and the aggressiveness of lung cancer cells. • VEGF-A induces AKT phosphorylation without affecting the EZH2 activity. • EZH2 promotes tumor progression via the PI3K/AKT pathway in NSCLC.
•The vascular water exchange MRI (VEXI) is a contrast-agent-free method proposed to assess BBB permeability•Apparent water exchange rate across BBB (AXRBBB) becomes higher specifically in the ...hippocampus, medial orbital frontal cortex, and thalamus in AD•AXRBBB is significantly correlated with cognitive dysfunction
Blood-brain barrier (BBB) impairment is an important pathophysiological process in Alzheimer's disease (AD) and a potential biomarker for early diagnosis of AD. However, most current neuroimaging methods assessing BBB function need the injection of exogenous contrast agents (or tracers), which limits the application of these methods in a large population. In this study, we aim to explore the feasibility of vascular water exchange MRI (VEXI), a diffusion-MRI-based method proposed to assess the BBB permeability to water molecules without using a contrast agent, in the detection of the BBB breakdown in AD. We tested VEXI on a 3T MRI scanner on three groups: AD patients (AD group), mild cognitive impairment (MCI) patients due to AD (MCI group), and the age-matched normal cognition subjects (NC group). Interestingly, we find that the apparent water exchange across the BBB (AXRBBB) measured by VEXI shows higher values in MCI compared with NC, and this higher AXRBBB happens specifically in the hippocampus. This increase in AXRBBB value gets larger and extends to more brain regions (medial orbital frontal cortex and thalamus) from MCI group to the AD group. Furthermore, we find that the AXRBBB values of these three regions is correlated significantly with the impairment of respective cognitive domains independent of age, sex and education. These results suggest VEXI is a promising method to assess the BBB breakdown in AD.
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•Spatiotemporally contiguous precipitation events are tracked through FiT algorithm.•Contiguous precipitation events exhibit different Spatiotemporal characteristics in different ...geographical locations.•Role of atmospheric rivers and tropical cyclones in heavy precipitation are explored.•Heavy events associated with TCs (ARs) mainly occur in southern (central and southern) China.•Heavy events associated with TCs (ARs) normally have higher maximum intensity (longer duration).
Precipitation events exhibit a spatiotemporal continuity since they move across both space and time, however, the joint spatiotemporal characteristics of precipitation events are often neglected, and the role of Atmospheric rivers (ARs) and tropical cyclones (TCs) in the events has not been systematically explored. To solve these problems, this study seeks to detect and characterize the three-dimensional (latitude + longitude + time) structures of spatiotemporally contiguous precipitation events, distinguish the heavy events associated with ARs or TCs, and systematically explore the different roles of these events. We do so by combining Forward-in-Time algorithm, an object-based physical event detecting algorithm, with TMPA precipitation estimates to detect spatiotemporally contiguous precipitation events over China, and an AR detection technique considering a combination of fixed lower limit and Integrated Water Vapor Transport percentile threshold is adopted to identify ARs. The heavy events are defined to analyze the differences of the events associated with TCs and ARs as a function of precipitation total, duration, and intensity. Results show that approximately half or more of precipitation events are shorter than 6-hour, and the precipitation total of each event is strongly correlated with maximum intensity and average intensity across China. The heavy events normally occur in southern, center, northern, and southwestern regions, where have approximately 10 to 40 heavy events at each grid. The fraction of heavy events associated with TCs generally increase for events with larger precipitation totals and for events with higher maximum intensity, until all of events are associated with TCs. The percentages of events associated with ARs as well normally increase as precipitation totals and maximum intensity increase up to around 150 mm and 30 mm/h, respectively. Our findings show that the events associated with TCs or ARs exhibit distinct different characteristics, and suggest that the different spatiotemporal dynamics should be sufficient considered in contiguous events analyses in different regions.
•Probability of slight drought was higher than moderate drought.•Range of single probability of slight drought was 26.15 to 41.06%•Range of joint probability of droughts in moderately was 3.76 to ...31.32%
Documenting the joint probability of meteorological-hydrological, meteorological-agricultural, and hydrological-agricultural drought can be invaluable for understanding drought evolution under climate change in a high-diversity watershed of south China. Through constructing the edge and joint distribution functions of multi drought indices (SPEI, SPI, SSI, and SWI) based on SWAT and copula methods, we explored the evolution of multi droughts under climate change in the East River basin. During 1997–2017 and 2023–2099, we used logistic, generalized pareto, and normal distributions to construct edge distribution functions of SPEI, SPI, SWI, and SSI. For the four indices, the probability of slight drought increased with rcp2.6, 4.5, 6.0, and 8.5, and it was higher than moderate drought. Also, Clayton, Frank, Gumbel, and Gaussian copula functions were used to construct joint distribution functions of SPEI and SSI, SPEI and SWI, SSI and SWI to quantify their interactions. During 1997–2017, the probability of slight drought was 26.15 to 41.06 %, and the return period changed from 3.8 to 2.4 years. The joint probability of meteorological-hydrological, meteorological-agricultural, and hydrological-agricultural drought in slightly was 24.4 to 31.32 %, 14.95 to 22.63 %, and 6.18 to 22.05 %, respectively. During 2023–2099, the joint probability of droughts in moderately was 3.76 to 14.19 %, and the return period was 7 to 26.6 years. Our results provide a quantitative assessment of single and joint probability of meteorological, hydrological and agricultural drought, which could be used to support watershed water resource management.
The impact of 0.1–10 MeV neutron-induced single-event upsets (NSEUs) on terrestrial SER (soft error rate) prediction is analyzed for several broad spectrum neutron sources based on 0.1–200 MeV NSEU ...energetic-dependent cross-sectional data of a 40 nm SRAM. The results show that for test facilities with abundant <10 MeV neutrons, such as ISIS ChipIR, J-PARC BL10, CSNS Back-n, and CSNS BL09, the terrestrial SER is overestimated. The overestimation could reach 78%–287%. By reducing the cutoff energy (Emin) from 10 to 6 MeV, the overestimation can be decreased. However, the overestimation can still reach up to 164% in this case, significantly larger than the results reported by previous studies. By analyzing the contribution of neutrons in different energy bins to NSEUs, the discrepancy is proved to be attributed to the sensitivity of NSEUs to 0.1–1 MeV neutrons, along with the overpopulation of 0.1–1 MeV neutrons for certain test facilities, such as ISIS ChipIR and CSNS BL09. Therefore, it is necessary to take 0.1–1 MeV NSEU sensitivity into account when studying the prediction method using broad spectrum neutron sources.
To identify the defining attributes, antecedents, consequences and empirical referents to form an operational definition of social isolation in people with type 2 diabetes.
The Walker and Avant ...approach.
An electronic search of the literature using China National Knowledge Infrastructure (CNKI), Wanfang database, PubMed, Web of Science, CINAHL, and PsycINFO informed the analysis. The search included both quantitative and qualitative studies related to social isolation in people with type 2 diabetes published in Chinese and English.
Of the 2918 articles identified, 21 ultimately met the inclusion criteria. The analysis identified the defining attributes of social isolation in people with type 2 diabetes as objective and subjective. Antecedents included five aspects: personal characteristics, disease-related physiological factors, and psychological, behavioral, and social factors. Consequences were identified as physiological, psychological, behavioral aspects and quality of life.
The operational definition of social isolation in people with type 2 diabetes is that due to personal characteristics, disease-related physiological factors, and psychological, behavioral, and social factors, people with type 2 diabetes will have limited social networks and social support, reduced social contact and social involvement, and/or negative feelings of disconnection from the outside world, which lead to adverse physiological, psychological, and behavioral outcomes and poor quality of life. Clinicians can further develop tools to measure social isolation in people with type 2 diabetes and analyze the path of the antecedents to social isolation to investigate the interplay between them in order to develop target interventions.
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