Search

One-dimensional TiO 2 nanostructure has been widely studied in the domain of photoelectrochemical water splitting. Nevertheless, the wide bandgap and fast carriers recombination of TiO 2 restrain its performance. In this study, two-dimensional N-doped γ-graphyne nanosheets were synthesized and employed in the reasonable design of TiO 2 heterostructure, facilitating carrier migration and water oxidation reaction. The photocurrent density of photoanode composed of N-doped γ-graphyne/TiO 2 nanorods reaches 1.48 mA cm−2, 1.72 times that of pristine TiO 2 at a bias of 1.23 V (vs. RHE). Meanwhile, the calculated applied bias photon-to-current efficiency increases from 0.25 % to 0.56 %. The combination of TiO 2 nanorods with layered semiconductive N-doped γ-graphyne contributes to the construction of charge transfer channels, regulating surface states and reaction sites, promoting the hole storage, and reducing the free energy barrier in the velocity determination process. This study sheds light on the design of N-doped γ-graphyne modified catalysts and facilitates their application in photoelectrochemical and photoelectrocatalytic fields. [Display omitted] • N-doped γ-graphyne/TiO 2 nanorod arrays heterojunction was successfully constructed. • The photocurrent density and photoconversion efficiency are obviouly elevated in photoelectrocatalytic water splitting. • The regulation of band engineering, charge transfer channels and reaction kinetics are achieved. • N-doped γ-graphyne nanosheets provide fast transfer channels and active sites for carrier migration and charge reaction. [ABSTRACT FROM AUTHOR]

In recent years, the unprecedented rising urbanization level and proliferation of distributed energy sources (DES) are motivating the transition of smart building from consumer to prosumer. In the context of mitigating upstream emission via reducing reliance on utility grids, the key challenge becomes realizing autonomous and economically optimal energy management within smart buildings. This paper innovatively proposes a Decentralized Autonomous Organization (DAO)-based energy management framework for smart buildings, where the mechanism of day-ahead scheduling DAO considering peer-to-peer (P2P) energy sharing is specifically investigated. Besides, a sequential preference satisfaction mechanism is designed to customize participants' special demands, thereby achieving effective energy matching. Considering potential communication failures between buildings in practical operations, this study develops a communication failure robust distributed algorithm to minimize operational costs and safeguard building's privacy. Extensive numerical studies for highly DES penetrated smart buildings successfully offers an operation cost reduction of 33.7% when considering preference satisfaction and P2P energy sharing in the day-ahead scheduling problem. Simulation results also demonstrates that the algorithm in this work excels in resisting potential communication failure during operation. • A DAO-based energy management framework is proposed for smart buildings. • Peer-to-peer energy sharing is incorporated in the day-ahead scheduling problem. • A preference satisfaction mechanism is modeled to customize participant's demand. • A communication failure robust distributed algorithm is developed. [ABSTRACT FROM AUTHOR]

An adaptive anti-saturation robust finite-time control algorithm (AARFTC) is designed for flexible air-breathing hypersonic vehicle (FAHV) under actuator saturations. Firstly, an adaptive fixed-time anti-saturation compensator (AFAC) is presented to drive system to faster leave the saturated region Compared to traditional anti-saturation compensators, the auxiliary variable of AFAC is able to realize faster and more accurate convergence when saturation disappears, which avoids the influence on convergent characteristics of tracking error. In addition, the novel adaptive law in AFAC can further shorten the duration of saturation and improve the convergent speed of tracking error via adjusting gain in AFAC according to saturation of actuator. Then, dynamic inversion control is combined with AFAC to establish anti-saturation controller for velocity subsystem. Secondly, differentiator-based backstepping control is combined with AFAC for height subsystem. Two recursive fixed settling time differentiators are utilized to approximate derivatives of virtual control signals exactly in fixed time, which avoids the complex computational burden residing in traditional backstepping control and improves convergent accuracy compared to command filtered backstepping control. Meanwhile, AFAC is utilized to suppress the influence of elevator saturation. Ultimately, multiple sets of simulations on FAHV subject to external disturbances, parametric uncertainties and actuator saturations are carried out to show the superiorities of AFAC and AARFTC. • AARFTC is proposed for FAHV to suppress effects of actuator saturations. • AFAC improves response speed and convergence precision of traditional compensators. • Novel adaptive law can shorten saturation duration and improve convergence speed. • Recursive fixed settling time differentiators are used to improve precision. [ABSTRACT FROM AUTHOR]

Novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is pandemic. However, data concerning the epidemiological features, viral shedding, and antibody dynamics between asymptomatic SARS-CoV-2 carriers and COVID-19 patients remain controversial. We enrolled 193 SARS-CoV-2 infected subjects in Ningbo and Zhoushan, Zhejiang, China, from January 21 to March 6, 2020. All subjects were followed up to monitor the dynamics of serum antibody immunoglobulin M (IgM) and IgG against SARS-CoV-2 using colloidal gold-labeled and enzyme-linked immunosorbent assays. Of those, 31 were asymptomatic SARS-CoV-2 carriers, 148 symptomatic COVID-19 patients, and 14 presymptomatic COVID-19 patients. Compared to symptomatic COVID-19 patients, asymptomatic carriers were younger and had higher levels of white blood cell and lymphocyte, lower level of C-reactive protein, and shorter viral shedding duration. Conversion of IgM from positive to negative was shorter in asymptomatic carriers than in COVID-19 patients (7.5 vs. 25.5 days, P = 0.030). The proportion of those persistently seropositive for IgG against SARS-CoV-2 was higher in COVID-19 patients than in asymptomatic carriers (66.1% vs. 33.3%, P = 0.037). Viral load was higher in symptomatic patients than presymptomatic patients (P = 0.003) and asymptomatic carriers (P = 0.004). Viral shedding duration was longer in presymptomatic COVID-19 patients than in asymptomatic carriers (48.0 vs. 24.0 days, P = 0.002). Asymptomatic carriers acquired infection more from intra-familial transmission than did COVID-19 patients (89.0% vs. 61.0%, P = 0.028). In 4 familial clusters of SARS-CoV-2 infection, asymptomatic carriers were mainly children and young adults while severe COVID-19 was mainly found in family members older than 60 years with comorbidities. Asymptomatic carriers might have a higher antiviral immunity to clear SARS-CoV-2 than symptomatic COVID-19 patients and this antiviral immunity should be contributable to innate and adaptive cellular immunity rather than humoral immunity. The severity of COVID-19 is associated with older age and comorbidities in familial clustering cases. [ABSTRACT FROM AUTHOR]

A supercavitating underwater vehicle uses gas or vapor to reduce its skin friction enabling it to travel up to speeds of 200 m/s. However, traveling at extreme speeds can be challenging for control design since sudden disturbances or faults, even for a short time, can lead to large deviations from the reference trajectory. This paper addresses the problem of controlling a supercavitating vehicle which incorporates the actuator constraints and loss of effectiveness of the cavitator. An adaptive control law is designed based on the backstepping control method which includes an adaptive fault-tolerant component. The bounded adaptive update law can estimate the upper bound of the unknown total uncertainties including those induced by actuator faults. The proposed control is shown to guarantee stability in the presence of faults by using Lyapunov theory. [ABSTRACT FROM AUTHOR]

A novel anti-saturation robust control algorithm (NARC) is presented for flexible air-breathing hypersonic vehicle (FAHV) with actuator saturation, including two controllers designed for velocity and height subsystem respectively. Firstly, an anti-saturation finite-time dynamic inversion controller is designed for velocity subsystem, in which an anti-saturation fixed-time compensator (ASFC) is proposed to ensure the stability of saturated system and make it exit saturated region faster. Compared with conventional anti-saturation compensator, the auxiliary variable of ASFC can converge with faster speed and higher precision when actuator is not saturated, which avoids the impact on original system. Secondly, an anti-saturation robust command filtered backstepping controller is designed for height subsystem, combining backstepping control, ASFC and a novel fixed-time filter (FTF). Compared with low pass filter, the FTF proposed can track input signal with faster response speed and higher precision without the need to select a smaller time constant, so as to avoid introducing high-frequency noise. Meanwhile, convergence domain of height subsystem can be reduced as well. Ultimately, simulations on FAHV with actuator constraints, parametric uncertainties and external disturbances are performed using the NARC and conventional anti-saturation controller respectively to demonstrate the superiority of NARC. • NARC is proposed for FAHV to suppress effect of actuator saturation. • NARC includes two controllers designed for velocity and height subsystem. • Auxiliary variable of ASFC can converge with higher accuracy and faster speed. • FTF is presented to acquire higher tracking precision and faster respond speed. [ABSTRACT FROM AUTHOR]

A global smooth sliding mode controller (GSSMC) is proposed for flexible air-breathing hypersonic vehicle (FAHV) under actuator faults and parametric uncertainties, consisting of global fast finite-time integral sliding surface (GFFIS), generalized smooth second-order sliding mode reaching law (GSRL) and smooth fixed-time observer. Firstly, nonlinear control-oriented model of FAHV is processed using input/output feedback linearization with flexible effects and actuator faults modeling as lumped matched disturbances. Secondly, a GFFIS is established to ensure finite-time convergence of states without singularity based on a newly proposed fast finite-time high-order regulator (FFR). The FFR is improved from standard finite-time high-order regulator via dilation rescaling, which can accelerate response speed avoiding complicated parameters selection. Meanwhile, GFFIS can eliminate initial reaching phase to enhance robustness of system due to characteristic of global convergence. Thirdly, a GSRL is presented to ensure finite-time convergence of sliding mode vector and its derivative without chattering based on a generalized smooth second-order sliding mode control algorithm, the stability and finite convergence time of which is analyzed via Lyapunov criteria in detail. Then, a smooth fixed-time observer is applied to estimate lumped disturbances in fixed time and avoid effects of parametric uncertainties. With the three components, GSSMC can drive FAHV subject to actuator faults and parametric uncertainties to follow desired values in finite time with smooth control signals. Ultimately, three sets of simulations are performed to verify the effectiveness of the methods proposed. [ABSTRACT FROM AUTHOR]

An improved robust fixed-time sliding mode controller (RFSMC) is presented for flexible air-breathing hypersonic vehicle (FAHV) with actuator faults, composing of a novel fast fixed-time integral sliding surface (FFIS), a continuous fixed-time super-twisting-like reaching law (CFSTL) and a uniformly convergent observer. Firstly, the nonlinear control-oriented model of FAHV is processed via input/output feedback linearization with flexible effects and actuator faults modeling as matched Lipschitz disturbances. Secondly, a novel non-singular FFIS is established based on a fast fixed-time high-order regulator (FFTR), which is improved with two gains incorporating into standard fixed-time high-order regulator via dilation rescaling. The FFTR proposed can accelerate respond speed of system by tuning values of two gains simply without complicated parameters selection and the stability is proved strictly via Lyapunov criteria. Thirdly, a CFSTL is utilized to ensure high-precision convergence of sliding mode vector and its derivative in fixed time. Afterwards, a uniformly convergent observer is applied to estimate lumped disturbances accurately in fixed time. With the estimated values compensated into controller, RFSMC can enhance fault-tolerant performance and attenuate chattering efficiently. Finally, simulations on FAHV are performed to verify the effectiveness and superiority of the method proposed. • RFSMC can make errors of FAHV under actuator faults converge in fixed time. • RFSMC comprises of FFIS, CFSTL and uniformly convergent observer. • FFIS is established based on fast fixed-time high-order regulator (FFTR). • FFTR can realize fixed-time convergence without complicated parameter selection. [ABSTRACT FROM AUTHOR]

Abstract A novel adaptive higher order super-twisting control algorithm (AHOSTC) is proposed for a flexible air-breathing hypersonic vehicle (FAHV). Firstly, the nonlinear control-oriented model (COM) is processed using input/output feedback linearization method. Therefore, significant flexible effects aroused by slender fuselage and strong coupling between propulsion and aerodynamic of FAHV could be considered during the application of model-based control techniques. Secondly, an adaptive control gain L is incorporated into normal higher order super-twisting algorithm (HOSTA) via dilation rescaling to improve speed of response and attenuate chattering, in the meanwhile, the matched disturbances can be compensated and the finite-time convergence can be achieved. In addition, gain L could be adjusted by the presented novel adaptive law automatically, especially when Lipschitz constants of disturbances are unknown and time-varying. Furthermore, the stability of adaptive law is analyzed via Lyapnuov criteria. Ultimately, compared with normal HOSTA, the proposed AHOSTC is able to enhance robustness and respond speed, while minimizing effects of chattering efficiently. Simulations on longitudinal model of FAHV are carried out to compare AHOSTC with normal HOSTA. The results demonstrate the superiority and effectiveness of AHOSTC under different simulation conditions, external disturbances and parametric uncertainties. Highlights • An adaptive higher order super-twisting control algorithm (AHOSTC) is proposed for FAHV. • AHOSTC can realize higher-precision finite-time convergence with continuous control signal. • AHOSTC can automatically compensate matched disturbances with unknown and time-varying Lipschitz constants. • AHOSTC is able to enhance the robustness and respond speed, while attenuating chattering efficiently. [ABSTRACT FROM AUTHOR]

An active adaptive continuous nonsingular terminal sliding mode algorithm (ACNTSM) is designed for hypersonic boost glide vehicle to achieve higher control accuracy and faster response speed. Firstly, a continuous nonsingular terminal sliding mode controller is presented to make the tracking error and sliding variable converge to zero under the effect of time-varying disturbance in finite time. Compared with traditional terminal sliding mode control using exponential approach law, the ACNTSM algorithm can generate continuous control signal, which effectively reduces chattering. Secondly, a novel active adaptive law is proposed to reduce convergence error, to avoid excessive gain, and to attenuate chattering by adjusting the gain of ACNTSM. The adaptive scheme includes sliding variable and disturbance estimation. The disturbance estimation is obtained by using the integral term of generalized super twisting sliding mode algorithm. The method takes less computational resources and reduces complexity of algorithm. In addition, the gain can automatically increase to shorten convergent time until the sliding mode is reached and then decrease to reduce chattering until the sliding mode is lost. The novel adaptive law ensures the finite-time convergence to a neighborhood of origin for sliding variable without overestimation of gain. Finally, numerical simulations are carried out to demonstrate the effectiveness and superiority of ACNTSM. [ABSTRACT FROM AUTHOR]

Nontyphoidal Salmonella (NTS) gastroenteritis is a widespread global foodborne disease. To identify the epidemiologic characteristics, sources of food contamination, and risk factors of NTS gastroenteritis, epidemiologic data and stool specimens of diarrheal patients were collected from sentinel hospitals in Baoshan, Shanghai, People's Republic of China, between 2010 and 2014. Food products from nearby farmers' markets and animal feces from live poultry markets and livestock farms were sampled to identify the pathogen; a case-control study was conducted to characterize risk factors of NTS gastroenteritis. Of 3,906 diarrheal patients examined, 266 (6.8%) were positive for Salmonella. The positive rates were higher in summer than in the other seasons. Salmonella Typhimurium (36.1%) and Salmonella Enteritidis (30.8%) were the dominant serovars in the patients. Salmonella was detected in 26.2% pork samples, 7.1 to 7.8% poultry meats, and 3.3 to 8.9% poultry feces. Salmonella Typhimurium was the major serovar in contaminated food and animal feces. Multivariate conditional logistic regression analysis indicated that consumption of pork and quickly cooked eggs increased, whereas separating kitchen knives for cooked and raw food decreased the risk of NTS gastroenteritis, independently. We believe that NTS in poultry feces contaminated the meat products in the same markets and then infected humans if these foods were not sufficiently cooked. To prevent NTS gastroenteritis, it is necessary to survey Salmonella in meats and poultry feces, to cook eggs and pork sufficiently, to separate kitchen knives for cooked and raw food, and to prohibit live poultry trade in fresh meat markets. [ABSTRACT FROM AUTHOR]

Drought propagation describes the changes in a drought signal as it moves from one major type of drought to another. It is important to investigate the propagation among meteorological, agricultural and hydrological drought, as well as their major impacting factors, to improve understanding of the drought propagation relationship, monitor agricultural drought and reduce crop losses. This study presents the first exploration of the interplay between multiple droughts among different climate zones and seasons in China. The standardized precipitation evapotranspiration index (SPEI), standardized runoff index (SRI) and self-calibrating Palmer drought severity index (scPDSI) were used to represent meteorological, agricultural and hydrological drought, respectively. The Pearson correlation coefficient was used to analyze the propagation relationships among different droughts and identify the most sensitive season for drought propagation. The Lindeman–Merenda–Gold (LMG) method was used to quantify the relative importance of PRE (precipitation), PET (potential evapotranspiration) and SM (soil moisture) to hydrological and agricultural drought. The propagation from meteorological to agricultural drought was prominent in different seasons at the annual scale over China. In general, the propagation relationship from agricultural to hydrological drought was weaker than that from meteorological to agricultural drought. In Northern China (arid and semi-arid areas), there was a stronger propagation relationship from agricultural to hydrological drought in summer and autumn than in spring. There was also stronger propagation from agricultural to hydrological drought in eastern China than in western China. Different climate regions had different major factors driving hydrological drought because of the different climate characteristics. However, SM was generally the most important driving factor for agricultural drought in all climate regions. Mulching plastic film might be an effective and feasible method to reduce PET from soil evaporation in sub-regions that apply high irrigation levels. These findings may also be applied to strengthen the study of artificial regulation of water resources, which could be an approach to reducing crop losses from drought. • The propagation between different drought types was strongest in summer. • Propagation from meteorological to agricultural drought was strongest in western China. • SM and PET were the main drivers of hydrological drought in arid and semi-arid areas. • SM was more important than PRE and PET in hydrological and agricultural drought. [ABSTRACT FROM AUTHOR]

Antibody-dependent cellular cytotoxicity (ADCC) is essential for reducing the reservoir of latent virus in persons living with HIV-1 (PLWH). This study evaluated the plasma's ADCC activity from treatment-naïve PLWH based on target cells with or without CD4 molecules. We found that the distribution of plasma activities to mediate ADCC is different between 8E5 cells (CD4-) and NL4-3-infected CEM.NKR.CCR5 cells (CD4+). There was no correlation between the IgG-binding ability and ADCC activity. The binding ability of the 8E5 cells (2.2%) to A32 antibody was significantly lower than that of CEM.NKR.CCR5 cells (69.3%). After incubating the 8E5 cells with CD4-mimetic compound, it did not increase the binding ability with the A32 antibody. After incubation with CD4+ T cells, the binding ability of the 8E5 cells for the A32 antibody increased significantly, which implies that the conformation of the Env protein open and expose the CD4-induced epitopes. The effect of the ADCC in plasma directly applied to 8E5 cells was positively correlated with that of the NL4-3-infected CEM.NKR.CCR5 cells. In conclusion, ADCC induction in plasma was general in the treatment-naïve PLWH. The ADCC activity levels differed when target cells with or without CD4 molecules were evaluated; When designing experiments on ADCC, full consideration should be given to this immune phenomenon. [ABSTRACT FROM AUTHOR]

• Most areas (80.1%) of China show increasing trends in the annual NDVI change. • Anti-trends of vegetation dynamic changes are found in most areas of China. • Vegetation dynamics in China are predicted from the perspective of water deficit. • Vegetation in China will have a greening trend under future scenarios till 2100. Vegetation is an important link between water, atmosphere and land, and the growth of vegetation is an important indicator of ecosystem change. Therefore, it is essential to study the dynamic changes of vegetation and predict the vegetation dynamics. Based on the Normalized Difference Vegetation Index (NDVI) and statistical analysis (e.g., trend analysis methods and Hurst exponent), this study investigates the historical dynamic changes of vegetation in China, and the multi-regression model was used to construct a predict model from the perspective of water deficit. The future features were predicted under two representative concentration pathway (RCP4.5 and RCP8.5) scenarios from 12 Coupled Model Inter-comparison Project phase 5 (CMIP5) models. The results showed that 1) most areas (80.1%) of China showed increasing trends in the annual NDVI change during 1982–2015, and the areas showing the degradation trends were mainly found in Northeast China, North Xinjiang and the Qinghai-Tibet Plateau; 2) the prediction model constructed by precipitation and reference crop evapotranspiration (ET 0) can well predict the vegetation dynamics in China; and 3) the future vegetation in China will be better than that in the past, except for some areas (e.g., the northeastern and southeastern parts of China) in spring, and the dynamic changes of vegetation under RCP8.5 scenario will be greater than that under RCP4.5 scenario. Nevertheless, in spring, vegetation degradation cannot be ignored. [ABSTRACT FROM AUTHOR]

Land surface vegetation dynamics are strongly affected by drought. Thus, understanding the responses of vegetation to drought can inform measures to increase biome stability. In this study, the normalized difference vegetation index (NDVI) and the Palmer drought severity index (PDSI) were utilized to investigate the relationship between vegetation activity and drought across different drought regions and ecological community types from 1982 to 2015. Our results showed that the highest correlation between monthly NDVI and PDSI at different timescales (1–36 months) indicated the degree of drought impact on vegetation. There were diverse responses of vegetation to drought according to the drought features and climatic environment. The northern grassland, cropland, and desert ecosystems were strongly impacted by drought. These vegetation ecosystems had a low sensitivity to drought in southern China. Drought had the strongest impact on grassland in summer, which is the high frequency drought season. The most susceptible ecosystem types to drought were those with homogenous vegetation, especially under long-term drought conditions (such as the Inner Mongolia Plateau dominated by grassland). Under global warming, drought with high-temperature characteristics is expected to become more frequent and severe. Such drought could threaten the survival of plateau grassland, arid plain grassland, and rain-fed cropland, as high temperatures accelerate evaporation, leading to water deficit. However, moist forests showed little threat under normal drought. We suggest that future research should focus on vegetation activity in northern and southwestern China, where the vegetation shows the greatest sensitivity to drought. Unlabelled Image • Low vegetation coverage levels were sensitive to drought. • Vegetation was more sensitive to drought in arid areas than in humid areas. • Drought resistance was associated with vegetation diversity and characteristics. • Climatic factors, human activities, and groundwater impacted vegetation response to drought. • Grassland and desert vegetation types were most vulnerable to drought. [ABSTRACT FROM AUTHOR]

• The SWAP model was well calibrated and verified its capability at the regional scale. • Increased precipitation was the determining factor in increasing evapotranspiration, and the adverse effect of temperature increase offset the promotion of yield due to radiation. • The synergistic effect of late-maturing varieties and irrigation adjustment can increase yield and crop water productivity under future climate. Climate change poses great challenges for food security and water use. This study aimed to investigate the response of winter wheat in Northern China to climate change and propose corresponding strategies to maintain yield and crop water productivity (WP c). Climate model projections from the fifth phase of the Climate Model Intercomparison Project (CMIP5) were used to drive the process-based soil–water–atmosphere–plant (SWAP) agro-hydrological model. The SWAP parameters were optimized by the Parameter Estimation program (PEST), which extended the crop model to the regional scale. SWAP was used to simulate responses of crop growth, evapotranspiration (ET), and yield to baseline (2006–2012) climate and two representative concentration pathway (RCP) scenarios (RCP4.5 and RCP8.5) for future climate conditions. The results indicated that PEST had high optimization efficiency and calibrated SWAP performed well (average relative error < 20.87 % and normalized root mean square error < 25.83 %). Compared with baseline, the maximum and minimum temperatures increased significantly (P < 0.05) by 6.47°C and 8.59°C, respectively. The cumulative precipitation during the growing season increased by 303.22–316.12 mm. Warming significantly (P < 0.05) reduced the growth period of winter wheat by 25.3–34.7 days, especially in the emergence–heading stage. Path analysis revealed that significant (P < 0.05) change of precipitation was a determining factor in increasing ET. The adverse effect of temperature increase offset the promotion of yield due to radiation, and ultimately led to a yield reduction of 35.57–41.14 %. The optimization scenario indicated that late-maturing varieties and irrigation adjustment could improve yield (up to 38.21 %) and WP c (up to 44.30 %) under future climate conditions. Implementing irrigation at an early growing stage (joining and heading) was beneficial to increase yield and WP c. We recommend combining late-maturing varieties with irrigation adjustments to maintain yield and WP c under future climate conditions. [ABSTRACT FROM AUTHOR]

The extremely poor prognosis of patients with symptomatic hepatocellular carcinoma (HCC) diagnosed clinically at advanced stages suggests an urgent need for biomarkers that can be used for prospective surveillance and pre-clinical screening for early presence of pre-malignant lesions and tumors. In a retrospective longitudinal phase 3 biomarker study in seven medical centers of China, time-series and 6 months interval-serum samples were collected from chronic hepatitis B virus infected (CHB) patient cohorts at the pre-malignant or pre-clinical stages (average 6 months prior to clinical diagnosis) and CHB patients that did not develop cancer, and circulating miRNAs measured. A set of serum miRNAs including miR-193a-3p, miR-369-5p, miR-672, miR-429 and let-7i* were identified in pre-clinical HCC patients and have the potential to screen for CHB patients at high risk to develop HCC 6-12 months after miRNAs measurement. These circulating miRNAs combined with the conventional screening tools using α-fetoprotein and ultrasound, may have great promise for the prediction and prevention of HCC in high-risk populations. [ABSTRACT FROM AUTHOR]

Abstracts Background Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne, novel bunyavirus-caused emerging infectious disease. It becomes a threat to public health due to its high fatality rate. Objective To clarify the epidemiological characteristics of SFTS and natural host(s) of SFTS-causing virus (SFTSV) in East China. Study design Serum antibody against SFTSV in 496 healthy villagers was examined by ELISA. SFTSV in acute sera of SFTS cases and lung tissues of house and field mouse/rats were identified using quantitative RT-PCR, cell culture, and sequencing. Results A total of 22 laboratory-confirmed SFTS cases were diagnosed between 2012 and 2014, of which 5 (22.7%) reported a history of tick-bites. The seroprevalance of SFTSV antibody was 10.5% in healthy villagers. SFTSV genomic RNAs were identified in 2 of 8 Apodemus agrarius but not in Rattus norvegicus ( n = 40) and Rattus losea ( n = 4). The 3 segments of SFTSV from 11 SFTS cases and 2 A. agrarius were successfully sequenced. Phylogenetic analyses indicated that at least 3 different SFTSV strains (inland-type, Ningbo-native-type, and their reassortant-type) were present in Ningbo. The 3 segments of the 2 SFTSV isolates from A. agrarius shared great sequence homologies to those isolated from the patients living in nearby villages. Conclusion The present study indicated that A. agrarius might be a natural host of SFTSV in East China. [ABSTRACT FROM AUTHOR]

Abstract: Background: NR4A2, an orphan nuclear receptor essential in neuron generation, has been recently linked to inflammatory and metabolic pathways of colorectal carcinoma (CRC). However, the effects of NR4A2 on chemo-resistance and postoperative prognosis of CRC remain unknown. Methods: NR4A2 was transfected into CRC cells to investigate its effects on chemo-resistance to 5-fluorouracil and oxaliplatin and chemotherapeutics-induced apoptosis. We also investigated prostaglandin E2 (PGE2)-induced NR4A2 expression and its effect on chemo-resistance. Tissue microarrays including 51 adenoma, 14 familial adenomatous polyposis with CRC, 17 stage IV CRC with adjacent mucosa and 682 stage I–III CRC specimens were examined immunohistochemically for NR4A2 expression. Median follow-up time for stage I–III CRC patients was 53months. Results: Ectopic expression of NR4A2 increased the chemo-resistance, and attenuated the chemotherapeutics-induced apoptosis. Transient treatment of PGE2 significantly up-regulated NR4A2 expression via protein kinase A pathway and increased the chemo-resistance. NR4A2 expression in epithelials consecutively increased from adenoma, adjacent mucosa to CRC (P trend <0.001). In multivariate Cox regression analyses, high NR4A2 expression in cancer nuclei (immunoreactive score⩾4) significantly predicted a shorter disease-specific survival (DSS) of CRC patients (hazard ratio [HR]=1.88, P =0.024). High NR4A2 expression specifically predicted a shorter DSS of colon cancer patients (dichotomisation, HR=2.55, log-rank test P =0.011), especially for those who received postoperative 5-fluorouracil/leucovorin plus oxaliplatin (FOLFOX) chemotherapy (3-score range, HR=1.86, log-rank test P =0.020). Conclusion: High expression of NR4A2 in CRC cells confers chemo-resistance, attenuates chemotherapeutics-induced apoptosis, and predicts unfavorable prognosis of colon cancer patients, especially for those who received postoperative chemotherapy. NR4A2 may be prognostic and predictive for colon cancer. [Copyright &y& Elsevier]

Abstract: Background: Outbreaks of hand, foot, and mouth disease (HFMD) in central China have caused public health concerns since 2007. It is of particular public health significance to update epidemiology of HFMD in port cities. Objective: To investigate epidemical, etiological and clinical characteristics of HFMD in Ningbo, China, from 2008 to 2011. Study design: From May 2008 to December 2011, a total of 37,404 HFMD cases including 196 severe and 12 fatal cases were investigated. Human enteroviruses from 2360 cases were determined by real-time RT-PCR. The VP1 gene of EV71 from 78 cases and CA16 from 21 cases, the VP4 gene from 28 cases, and full-length genomes of 10 isolates were analyzed. Neutralizing antibodies were evaluated in 258 healthy subjects. Parameters associated with severe HFMD were evaluated. Results: Annual incidence of HFMD was 3066.8/100,000 in the population of ≤5 years. EV71 C4a, CA16 B1, and other enteroviruses accounted for 63.7%, 24.0% and 12.3%, respectively. The genomes of EV71 from fatal and non-fatal cases were nearly identical. The positive rates of neutralizing antibody to EV71 increased from 13.5% to 67.6% in 1- to 5-year healthy groups. The neutralizing antibody to CA16 B1 isolate was negative. EV71, exposure history and certain early manifestations including fever, vomiting, limb exanthema and peripheral neutrophil ratio were significantly associated with HFMD severity. Conclusions: HFMD mainly caused by EV71 C4a and CA16 B1 is seriously epidemic in Ningbo. Future emphasis should be paid on EV71 immuno-prophylaxis and early identification of severe cases upon the etiological and clinical characteristics. [Copyright &y& Elsevier]

[Display omitted] • Analyzed spatiotemporal characteristic of NDVI variation affected by climatic factors. • Predicted future vegetation conditions in China combined with two carbon scenarios. • Insignificant impact of carbon concentration on NDVI trend in vegetation types zone, but large impact in partial areas. • Different influence of carbon concentration on NDVI cycle with each month. • No impact of carbon concentration on NDVI amplitude. Currently, studies analysing the relationship between climatic factors and vegetation may present some problems, including considering insufficient spatiotemporal characteristics, contradictory results and deficiencies in reflecting vegetation changes in the future. To address this, we first analysed the spatiotemporal characteristics of the impact of climatic factors on the normalized difference vegetation index (NDVI) using a multiple regression model constructed from the perspective of water deficit. Second, the two carbon emission scenarios provided by Coupled Model Inter-comparison Project phase 5 (CMIP5) were combined to predict the future vegetation conditions in China. Finally, trend analysis, Sen's slope and cycle analysis methods were employed to explore the trend of the NDVI and its spatiotemporal characteristics in the arid and semiarid regions of China. The results show that the impact of climate change on vegetation possesses distinct spatiotemporal characteristics, and the influences are different depending on the month and location. Vegetation has greened in most arid and semiarid areas of China during historical periods. In the future, NDVI variation will show a fluctuating tendency, and increasing and declining trends for the NDVI will alternately occur monthly. Although both precipitation and temperature will increase in the future, spring vegetation will be threatened by stress in some areas due to severe drought caused by the increase in evaporation, which is caused by increasing temperature. The impact of climatic factors on the amplitude and cycle of vegetation type zones varies monthly. The impact of carbon concentration on the NDVI in vegetation type zones was not significant but was relatively large in some areas. The influence of the carbon concentration on the NDVI cycle is different each month. Carbon concentration basically has no effect on amplitude. [ABSTRACT FROM AUTHOR]

• The influence of steam curing parameters on the sorptivity coefficient of steam-cured concrete is investigated. • Surface treatments of concrete before the heating stage are helpful to reduce the capillary water absorption. • Multivariable regression models can predict sorptivity coefficient of steam-cured concretes by steam curing parameters. Effects of steam curing parameters on the capillary water absorption (CWA) of concrete are investigated, and the models related to steam curing parameters for predicting the sorptivity coefficient of concrete are developed using extensive experimental database. The results show that the CWA and sorptivity coefficient of steam-cured concrete is closely related to the steam curing regimes and the surface condition of concrete. Longer precuring time or lower heating rate can reduce the CWA and sorptivity coefficient of steam-cured concrete. When the treatment time is 8 h, higher and lower treatment temperature can increase the CWA and sorptivity coefficient of concrete. When the treatment temperature is 60 ℃, the CWA and sorptivity coefficient of concrete increase with the treatment time. Highest cooling rate will lead to highest sorptivity coefficient of steam-cured concrete. The CWA and sorptivity coefficient of top surface are higher than that of side surface, and the CWA and sorptivity coefficient of surface concrete are higher than that of the interior concrete. In addition, the surface treatment methods of quadric-plastering and covering film can reduce the CWA and sorptivity coefficient of concrete. Finally, linear regression analysis and multiple nonlinear regression are employed to simulate the sorptivity coefficient of steam-cured concrete. The multivariable regression analysis method gives an explicit formula that achieves a good predictive result. [ABSTRACT FROM AUTHOR]

• Optimal irrigation could be adjusted in variable precipitation years in Guanzhong Plain. • Maize seedling and wheat jointing stages were the sensitive phases to water deficit. • Irrigation at different crop growth stage significantly influenced N leaching and NUE. • Increasing N input led to higher WUE and lower deep percolation water. • Appropriate N rates were 140 and 240 kg N ha-1 for maize and wheat, respectively. Irrigation and nitrogen (N) fertilization play important roles in grain yield. However, amounts supplied in excess of crop demand are responsible for water and N leaching during intensive agricultural production. A three-year winter wheat (Triticum aestivum L.)-summer maize (Zea mays L.) rotation experiment involving varied irrigation and N fertilization treatments was conducted in the Jinghui Canal irrigation area of Guanzhong Plain in China. To develop a more sustainable agroecosystem taking into account crop yields, deep percolation and N leaching, the RZWQM2 model was used to simulate crop production. Various irrigation and N fertilization strategies were simulated to obtain high crop yields and to reduce water and N leaching in different precipitation years, using long-term historical weather data spanning 57 years (1961–2017). The simulated soil water and NO 3 -N content, grain yield, water and nitrogen use efficiencies (with nRMSE values ranging from 5.3–25.1 %), and the simulated crop biomass and N uptake (with RE values ranging from -16.4–18.3 %) were in good agreement with observed data. Simulated LAI values were acceptable (with RMSE ranging from 0.31 to 1.68 and index of agreement, d , ranging from 0.28 to 0.94), with the poorer simulations occurring with water and N stress. Maize seedling stage and wheat jointing stage were the phases most sensitive to water deficit, and optimal irrigation schedules could be adjusted according to variable precipitation and other climate changes. The best irrigation strategies for maize in the Guanzhong Plain were irrigation applied at the seedling stage in wet and normal years, and two irrigations applied at the seedling and jointing stages in dry years. The best irrigation strategies for wheat were two, three, and four irrigations applied in wet, normal, and dry years, respectively. Irrigation at different crop growth stages significantly influenced N leaching and nitrogen use efficiency. Increasing N input led to greater water use efficiency and less deep percolation water. Considering the interactive effects of water and N input on yield, deep percolation, and N leaching, the most appropriate N application rates in all precipitation years were 140 kg N ha-1 for maize and 240 kg N ha-1 for wheat, coupled with the recommended irrigation strategies. Improving water and N management can significantly reduce deep percolation of water and N leaching while maintaining agricultural productivity and environmental sustainability. [ABSTRACT FROM AUTHOR]