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Large-scale disasters can disproportionately impact different population groups, causing prominent disparity and inequality, especially for the vulnerable and marginalized. Here, we investigate the resilience of human mobility under the disturbance of the unprecedented ‘720’ Zhengzhou flood in China in 2021 using records of 1.32 billion mobile phone signaling generated by 4.35 million people. We find that although pluvial floods can trigger mobility reductions, the overall structural dynamics of mobility networks remain relatively stable. We also find that the low levels of mobility resilience in female, adolescent and older adult groups are mainly due to their insufficient capabilities to maintain business-as-usual travel frequency during the flood. Most importantly, we reveal three types of counter-intuitive, yet widely existing, resilience patterns of human mobility (namely, ‘reverse bathtub’, ‘ever-increasing’ and ‘ever-decreasing’ patterns), and demonstrate a universal mechanism of disaster-avoidance response by further corroborating that those abnormal resilience patterns are not associated with people’s gender or age. In view of the common association between travel behaviors and travelers’ socio-demographic characteristics, our findings provide a caveat for scholars when disclosing disparities in human travel behaviors during flood-induced emergencies.

The complex micro-interfacial interaction theories of heavy metal ions such as Pb(II) and Cd(II) adsorption on fine sediment in aqueous solution were not systematically investigated. The aim of this work was to reflect the micro-interfacial adsorption characteristics. Sediment samples were collected from an estuary. The Isothermal and kinetics adsorption experiment were done to acquire the data. Isothermal, kinetics, film diffusion and intraparticle diffusion models were adopted to fit the adsorption experimental data. The results indicated that the Langmuir, Freundlich and Temkin models were suitable for analyzing the isothermal experimental data. The maximum adsorption capacities of Pb(II) and Cd(II) on the sediment were 1.1377 and 0.9821 mg·g−1, respectively. The qm and KL of the Langmuir model, Kf and nF of the Freundlich model, and b and A of the Temkin model all exhibited a power function relationship with the initial adsorbate concentration. The pseudo-second-order model provided a better fit for the experimental kinetics data compared with the fit of the pseudo-first-order and Elovich models. The pseudo-second-order parameters k2 and qe of Pb(II) and qe of Cd(II) both had a power function relationship with adsorption time, additionally, the k2 of Cd(II) had an exponential function relationship with adsorption time. The liquid-film diffusion parameters kfd of Pb(II) and Cd(II) were 0.0569 and 0.1806 min−1, respectively. The intraparticle diffusion parameter kid values of Pb(II) and Cd(II) were 0.0055 mg·g−1·min1/2 and 0.0049 mg·g−1·min1/2, respectively. The physical significance of the model parameters showed that Pb(II) adsorption on sediment was stronger than Cd(II). The results of this study provided a theoretical reference for the micro-interfacial mechanism of heavy metal ion adsorption on sediment.

The factors affecting debris flow runout volume changed considerably in the Wenchuan earthquake area. The main characteristic parameters for calculating the debris flow runout volume, namely, channelized landslide dam volume are first used to establish empirical models. A new empirical statistical model is established by applying a multivariate regression analysis to the runout volumes of dam-break and non-dam-break debris flows. Additionally, FLO-2D is used to simulate the debris flow runout volumes under the non-dam-breaking and dam-breaking scenarios. When the rainfall frequency is P = 1%, the predicted runout volumes in the Huaxi gully are 24.48 × 104 m3 under the non-dam-breaking scenario and 43.41 × 104 m3 under the dam-breaking scenario. The runout volume in the dam-breaking scenario is 6.07 × 104 m3 more than 1.77 times that in the non-dam-breaking scenario. The predicted runout range of the dam-breaking scenario is 1.16 times that of the non-dam-breaking scenario. The predicted alluvial fan areas and average accumulation depths in the dam-breaking scenario are larger than those in the non-dam-breaking scenario. The predicted runout volume of the dam-breaking scenario is 5.58 × 104 m3 which is less than the actual surveyed volume (48.99 × 104 m3). The relative error and accuracy of the numerical simulation results are −11.39 and 88.61% for the dam-breaking scenario. The new runout volume model was developed in catchments with abundant loose materials in the Wenchuan earthquake area and can thus be applied to debris flow gullies in meizoseismal areas with newly fractured regolith and abundant loose material to estimate runout volumes. The results of this study will help authorities select safe sites for future rehabilitation and relocation projects and can also be used as an important basis for debris flow risk management.

This study represents an approach to assess the hydrologic effectiveness of low impact development (LID) practices based on the expected runoff process with different objectives and land utilization. The proposed approach is to simulate runoff hydrograph rather than several indices (e.g., runoff initiation, peak flow, and runoff volume) to avoid the uncertainties under a certain rainfall scenario. A rainfall-runoff model of a residential district in China, constructed based on the stormwater management model (SWMM), is auto-calibrated (validated) based on 12 (25) observed rainfall and runoff events using model-independent parameter estimation (PEST). The priority sites and parameters for LID practices for different objectives are auto-calculated using PEST based on the calibrated model and different expected runoff processes. The expected runoff processes are simulated from the calibrated model with four impervious cover scenarios corresponding to 5-year, 2-h duration design storm. The study illustrates that (i) the proposed approach can auto-optimize runoff manage strategies based on LID practices and land; (ii) the design parameters of LID practices can be auto-calculated and that simulated runoff processes are in near perfect agreement with expected runoff processes; (iii) this approach can auto-optimize any specific parameters of the SWMM and LID practices without changing those determined parameters. Our simple, but quantitative, approach for identifying potential LID sites and design parameters based on land can better inform the hydrologic effectiveness of LID practices for managing runoff.

In this work, fluorinated graphene nanoscrolls (FGN) were synthesized via facile chemical methods under simple and mild conditions. Interestingly, the formation of the featured FGN was significantly solvent sensitive. Experimental results indicated that in the presence of aprotic solvent, for example, N,N dimethylformamide (DMF), the reaction system inclined to form the interesting FGN nanostructures. The structure and morphology of the prepared FGN were detailed characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) etc. The obtained FGN was used as a cathode material for primary lithium ion batteries with superior discharge specific capacity (eg. 979.3 mAhg-1), stable discharge platform and high energy density (eg. 2287.9 Wh kg-1), which fosters it a high density, low cost and durable candidate for cathode material for lithium ion batteries..

Water plays an essential role in social and economic sustainable development, and the relationship between socio-economic development and water resources sustainable utilization has been an important issue in water resources management. We aim to propose a water resources vulnerability assessment index with the dimensions of exposure, sensitivity and adaptability, and establish a water resources system model over the Pearl River Delta network river region based on the Vulnerability Scoping Diagram (VSD) framework and System Dynamics (SD) model. The city of Zhongshan, which is located in the Pearl River Delta is used as a case study. The vulnerability of the water resources in Zhongshan from 2021 to 2050 is simulated in four different scenarios (normal, technical innovation, social economic improvement, and comprehensive development models). The results showed that the vulnerability in all four scenarios span three grades in 30 years, including moderately vulnerable, slightly vulnerable, and not vulnerable. Among them, similar trends were found between scenarios 1 and 3, and between scenarios 2 and 4. Furthermore, the vulnerability level in scenarios 2 and 4 was lower than that in scenarios 1 and 3. The vulnerability of both scenarios 2 and 4 decreased first and then increased, with the average values of 24.64 and 27.63, respectively. Scenario 2 experienced 7 years of not vulnerable (2034 to 2040) and 23 years of slightly vulnerable (2021–2033, 204–2050), scenario 4 experienced 5 years of not vulnerable (2032–2036), 21 years of slightly vulnerable (2021–2031, 2037–2046), and 4 years of moderately vulnerable (2047–2050). Although the vulnerability of scenario 4 was slightly worse than scenario 2, its adaptability to economic and social development, water resources, and water environment was much higher than scenario 2. Considering the extent of socio-economic development and the level of adaptability of the local water resources and water environment, the study concluded that the comprehensive development model is more suitable for cities in the network river area. In this scenario, sustainable water use and management can be made possible through policy regulation that encourages higher water efficiency, sewage reuse rate, and centralized sewage treatment rate.

This study aimed to explore the effects of postnatal low-concentration arsenic exposure on learning, social skills and frontal cortex neurogenesis in rats. Water-based arsenic exposure rat models were established on postnatal days 4–10 (P4-P10). The experimental animals were divided into four groups: the control group, a 15 μg/L As 2 O 3 water group, a 30 μg/L As 2 O 3 water group, and a 45 μg/L As 2 O 3 water group. Cognitive function was examined with the Morris water maze, anxiety-like behavior with the open field test and light-dark box test, and social skills with a social interaction test. The frontal cortices of pups from each experimental group were sectioned at various time points after arsenic exposure. The morphologies and neurogenesis of the neurons in the frontal cortices were observed by hematoxylin-eosin staining, Nissl staining, and doublecortin (DCX) immunostaining. Significant positive correlations between arsenic concentration and deficits in learning and social skills were found, and the arsenic exposure groups showed significant increases in anxiety-like behavior compared with the control group (all Ps ). Abnormal morphologic changes in the external granular layer and external pyramidal layer were positively correlated with the water arsenic concentration in the acute phase of arsenic exposure. However, at five weeks after arsenic exposure, the frontal cortex morphology was restored. Moreover, immunohistochemistry revealed that compared to the control group, the groups that were exposed to arsenic exhibited significantly higher levels of DCX expression in the external granular and external pyramidal layers (all Ps 0.001). Furthermore, the 30 μg/L and 45 μg/L arsenic exposure groups still showed some DCX expression at five weeks after exposure. In conclusion, postnatal low-concentration arsenic exposure impaired learning and social skills and increased anxiety-like behaviors, and abnormal frontal cortex neurogenesis may be the mechanism underlying these effects.

This paper presents an energy management model for electric vehicles (EVs) and thermostatically controlled loads (TCLs) in intelligent energy systems based on the transactive control of aggregators. The management strategy will penetrate through three physical layers of electricity networks: transmission layer, distribution layer, and behind-meter layer. In the proposed framework, the aggregated EVs are modeled as a battery energy storage system (BESS), and the aggregated TCLs are modeled as a virtual energy storage system (VESS) at the behind-meter layer. A deep learning method, namely a hybrid of convolutional neural networks and long short-term memory (CNN-LSTM), is used to forecast the local loads of EVs and TCLs. The aggregators can dispatch these controllable loads directly as demand management to fit the predicted load curve. Peer-to-peer (P2P) trading is realized at the distribution level, and distributed optimization is utilized since the information between each aggregator is opaque. The primal problem is decoupled into subproblems of aggregators. The sub-gradient method is employed to update the multipliers of each decomposed Lagrange function. After the local energy transaction is cleared at the distribution level, wind generators and thermal generators are centrally dispatched at the transmission level based on the conventional optimal power flow model. The proposed hierarchy framework is verified in the IEEE 30-bus system. Simulation results reveal that the scalability issue of single-layer centralized dispatch can be well addressed, and end-users’ information privacy can be protected. The coordinated management of EVs and TCLs also brings in economic and environmental benefits.

This work investigates the adsorption of Cu ions in sediments by conducting batch experiments, including isothermal experiments and adsorption kinetics experiments. Data from isothermal experiments were analyzed using the Langmuir, Freundlich and Temkin models, and the experimental kinetic data were fit using pseudo-first-order, pseudo-second-order, Elovich, liquid film diffusion and intra-particle diffusion models. The Langmuir model resulted in the best fit for the equilibrium data, which indicated that the adsorption capacity of Cu ions on the sediment was 1.0403 mg g −1 with a K L value of 4.2877 L mg −1 . The Freundlich and Temkin models also provided good fits, and the n F and A values were 3.8565 and 66.9964 L mg −1 , respectively, indicating stronger adsorption intensities and adsorption energies between the Cu ions and the sediment. Compared with the pseudo-first-order and Elovich models, the pseudo-second-order model was more appropriate for describing the adsorption kinetics, indicating the chemisorption nature of adsorption. The adsorption kinetic process can be divided into film diffusion, pore diffusion and adsorption reactions. The controlling step for the adsorption kinetics changed with the development of the adsorption process. The entire adsorption process took 180 min. Film diffusion was the controlling step for the first 20 min. During the 20 to 60 min period, the pore diffusion gradually increased and the film diffusion decreased so that both phenomena coexisted. Pore diffusion was the controlling step during the 60–180 min period.

Background: Bilinguals are people that can use two languages for oral communication. Many bilinguals have specific language-associated cortical regions. This study aimed to analyze the cortical positioning features of vocal, semantic, and graphemic task zones in unskilled late Chinese (first)-English (second) (ULCE) bilinguals using the blood-oxygen-level dependent functional magnetic resonance imaging (BOLD-fMRI) technique. Methods: Twelve ULCE bilinguals were assigned Chinese-English (C-E) vocal, semantic, and graphemic tasks; SPM8 software was used to compare and investigate the brain activation maps towards different language tasks and to calculate their corresponding lateralization indexes (LIs). Results: These three language tasks in simple Chinese could activate most traditional language zones, which all exhibited obvious left-deviated activation dominance. A simple English task could also activate most traditional language zones, but only the semantic task appeared to have obvious left-deviated lateralization. However, none of the three tasks displayed any specific language zones between Chinese and English on the group level. Conclusions: Vocal, semantic, and graphemic tasks can all activate multiple brain regions in the language network and reflect their respective cognitive processing characteristics. Bilingual processing in ULCE bilinguals has similar neural mechanisms, but the left-deviated lateralization is not obvious when performing English vocal and graphemic tasks.

Background The mental health and quality of life in children with asthma have attracted widespread attention. This study focused on the evaluation of mental health conditions and their clinical characteristics in Chinese children with asthma. Methods A total of 261 children with asthma aged 6 to 16 years old and 261 age- and gender-matched children from the general population were recruited to participate in this study from Guizhou Provincial People’s Hospital. The parents of all subjects were interviewed using the MINI Kid and were required to finish a clinical characteristics questionnaire. Logistic regression analysis was performed to evaluate risk factors. Results The prevalence of mental health conditions in the asthma group was significantly higher than that in the control group (26.4% vs 14.6%, P ). A total of 10 mental health conditions was identified in the asthma group, the most common of which was ADHD (11.5%; 30/261), followed by oppositional defiant disorder (ODD) (10.7%; 28/261), separation anxiety disorder (6.1%; 16/261), social anxiety disorder (3.8%; 10/261), specific phobias (2.3%; 6/261), agoraphobia without panic (1.5%; 4/261), (mild) manic episodes (1.1%; 3/261), major depressive episodes (MDEs) (0.8%; 2/261), movement (tic) disorder (0.8%; 2/261), and dysthymia (0.4%; 1/261). A total of 6 neuropsychiatric conditions was detected in the control group, including ODD (5.7%; 15/261), ADHD (4.6%; 12/261), social anxiety disorder (3.1%; 8/261), seasonal anxiety disorder (SAD) (2.3%; 6/261), specific phobias (1.1%; 3/261), and agoraphobia without panic (0.4%; 1/261). The prevalence rates of ODD, ADHD, and SAD differed significantly between the two groups (P 3 years (OR = 2.948, 95% CI 1.580–5.502) were independent risk factors for the presence of mental health conditions in asthmatic children. Conclusions Children with asthma have a higher rate of mental health conditions than non-asthmatic children. Standardized diagnosis and treatment may help reduce the risk of neuropsychiatric conditions.

Additional file 1: This file included the “Introduction to the diagnostic sensitivity of the Chinese version of the MINI Kid for different neuropsychiatric diseases” and “The demographics and asthma clinical characteristics questionnaire”.

Urban inundation is a serious challenge that increasingly confronts the residents of many cities, as well as policymakers. Hence, inundation evaluation is becoming increasingly important around the world. This comprehensive assessment involves numerous indices in urban catchments, but the high-dimensional and non-linear relationship between the indices and the risk presents an enormous challenge for accurate evaluation. Therefore, an approach is hereby proposed to qualitatively and quantitatively evaluate inundation risks in urban drainage systems based on a storm water management model, the projection pursuit method, the ordinary kriging method and the K-means clustering method. This approach is tested using a residential district in Guangzhou, China. Seven evaluation indices were selected and twenty rainfall-runoff events were used to calibrate and validate the parameters of the rainfall-runoff model. The inundation risks in the study area drainage system were evaluated under different rainfall scenarios. The following conclusions are reached. (1) The proposed approach, without subjective factors, can identify the main driving factors, i.e., inundation duration, largest water flow and total flood amount in this study area. (2) The inundation risk of each manhole can be qualitatively analyzed and quantitatively calculated. There are 1, 8, 11, 14, 21, and 21 manholes at risk under the return periods of 1-year, 5-years, 10-years, 20-years, 50-years and 100-years, respectively. (3) The areas of levels III, IV and V increase with increasing rainfall return period based on analyzing the inundation risks for a variety of characteristics. (4) The relationships between rainfall intensity and inundation-affected areas are revealed by a logarithmic model. This study proposes a novel and successful approach to assessing risk in urban drainage systems and provides guidance for improving urban drainage systems and inundation preparedness.

Pumped-storage power plant(PSPP) is a special form of power supply. It is expected that the installed capacity of PSPP in China will reach 90GW by 2025. This paper summarizes the development of PSPP in China, and analysis the influencing factors of the configuration of PSPP, introduces the typical operation mode of PSPP and the existing problems in its development, and puts forward relevant policy suggestions for the development of PSPP.

Extreme precipitation occurs frequently because of hydrological variability, resulting in humid cities facing serious waterlogging problems. Previous studies about rainstorms had emphasized on spatial–temporal distribution characteristics, but rarely on rainfall pattern (RP). With a typical humid city in southern China, such as Guangzhou City in Guangdong Province as the research object, hourly precipitation data from January 2009 to October 2014 are collected from five meteorological stations in Guangzhou. The data are counted and classified by fuzzy mode recognition method according to seven typical rainfall patterns (STRP) and the Huff rainfall pattern (Huff RP). Subsequently, the distributive characteristics of urban rainstorm pattern (RSP) are analyzed. The main results obtained are as follows: (1) annual rainstorm days have high positive correlation with rainfall days, and the annual amount of rainstorm contributes to 7.5–50.5% of the annual total rainfall in Guangzhou, (2) large-scale rainfall is highly possible to occur in Guangzhou, (3) most rainstorms in Guangzhou are unimodal, of which the frontal peak is more than 70%, and (4) STRP are appropriate for RSP division in Guangzhou City.