Dynamic in situ reconstruction of NiSe_(2) promoted by interfacial Ce_(2)(CO_(3))_(2)O for enhanced water oxidation

Understanding and manipulating the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity.Herein,we present a synthesis of NiSe_(2)-Ce_(2)(CO_(3))_(2)O heterostructure and demonstrate the efficacy of interfacial Ce_(2)(CO_(3))2O in promoting the formation of catalytically active centers to improve oxygen evolution activity.In-situ Raman spectroscopy shows that incorporation of Ce_(2)(CO_(3))2O into NiSe_(2) causes a cathodic shift of the Ni^(2+)→Ni~(3+) transition potential.Operando electrochemical impedance spectroscopy reveals that strong electronic coupling at heterogeneous interface accelerates charge transfer process.Furthermore,density functional theory calculations suggest that actual catalytic active species of NiOOH transformed from NiSe_(2),which is coupled with Ce_(2)(CO_(3))_(2)O,can optimize electronic structure and decrease the free energy barriers toward fast oxygen evolution reaction(OER) kinetics.Consequently,the resultant NiSe_(2)-Ce_(2)(CO_(3))_(2)O electrode exhibits remarkable electrocatalytic performance with low overpotentials(268/304 mV@50/100 mA cm^(-2)) and excellent stability(50 mA cm^(-2) for 120 h) in the alkaline electrolyte.This work emphasizes the significance of modulating the dynamic changes in developing efficient electrocatalyst.

Three- and Four-Dimensional Generalized Pythagorean Numbers

The Pythagorean triples (a, b | c) of planar geometry which satisfy the equation a2+b2=c2 with integers (a, b, c) are generalized to 3D-Pythagorean quadruples (a, b, c | d) of spatial geometry which satisfy the equation a2+b2+c2=d2 with integers (a, b, c, d). Rules for a parametrization of the numbers (a, b, c, d) are derived and a list of all possible nonequivalent cases without common divisors up to d2 is established. The 3D-Pythagorean quadruples are then generalized to 4D-Pythagorean quintuples (a, b, c, d | e) which satisfy the equation a2+b2+c2+d2=e2 and a parametrization is derived. Relations to the 4-square identity are discussed which leads also to the N-dimensional case. The initial 3D- and 4D-Pythagorean numbers are explicitly calculated up to d2, respectively, e2.

Prevalence and intensity of urinary schistosomiasis and soil-transmitted helminths among women of reproductive age in Mwaluphamba,Kwale

Objective:To assess the epidemiology of urinary schistosomiasis and soil-transmitted helminthiasis among women of reproductive age in Mwaluphamba,Kwale County,Kenya.Methods:A community-based cross-sectional study design was employed to randomly sample 422 women of reproductive age(15-<50 years)from four villages in Mwaluphamba location.Stool specimens were collected and examined using the Kato-Katz method,while filtration technique was used to analyze urine specimens.Participants’sociodemographic details were obtained using a standardized questionnaire.Results:Urinary schistosomiasis prevalence was at 4.7%(20/422,95%CI 2.8%-6.9%)while the prevalence of soil-transmitted helminthiasis infection was 4.5%(19/422,95%CI 2.6%-6.7%).The infection intensities of urinary schistosomiasis among the study participants ranged from 1 to 120 eggs/10 mL of urine with median egg count of 18.45 eggs/10 mL.The patients were diagnosed with light infection,of 56.16 egg/gram and 48.48 egg/gram for Trichuris trichiura and hookworms,respectively.Women without latrines had 15.7 times higher risk of having urinary schistosomiasis compared to those with a latrine.Similarly,use of surface water(aOR=1.0,95%CI 0.2-1.4,P=0.010)and crossing the river to go to a place(aOR=1.1,95%CI 0.3-1.6,P=0.009)were statistically significant risk factors for getting urinary schistosomiasis.In bivariable regression analysis,defecating around the water source(OR=4.3,95%CI 1.5-12.9)had a statistically significant association with the prevalence of soil-transmitted helminthiasis(P=0.008).Conclusions:This study has given an insight on the prevalence and intensity of urinary schistosomiasis and soil-transmitted helminthiasis in Mwaluphamba location that form a basis for strengthening the control and elimination programmes for these neglected tropical diseases.

Fixed-time group consensus of second-order multi-agent systems based on event-triggered control

The problem of fixed-time group consensus for second-order multi-agent systems with disturbances is investigated.For cooperative-competitive network,two different control protocols,fixed-time group consensus and fixed-time eventtriggered group consensus,are designed.It is demonstrated that there is no Zeno behavior under the designed eventtriggered control.Meanwhile,it is proved that for an arbitrary initial state of the system,group consensus within the settling time could be obtained under the proposed control protocols by using matrix analysis and graph theory.Finally,a series of numerical examples are propounded to illustrate the performance of the proposed control protocol.

Path integral solutions for n-dimensional stochastic differential equations underα-stable Lévy excitation

In this paper,the path integral solutions for a general n-dimensional stochastic differential equa-tions(SDEs)withα-stable Lévy noise are derived and verified.Firstly,the governing equations for the solutions of n-dimensional SDEs under the excitation ofα-stable Lévy noise are obtained through the characteristic function of stochastic processes.Then,the short-time transition probability density func-tion of the path integral solution is derived based on the Chapman-Kolmogorov-Smoluchowski(CKS)equation and the characteristic function,and its correctness is demonstrated by proving that it satis-fies the governing equation of the solution of the SDE,which is also called the Fokker-Planck-Kolmogorov equation.Besides,illustrative examples are numerically considered for highlighting the feasibility of the proposed path integral method,and the pertinent Monte Carlo solution is also calculated to show its correctness and effectiveness.

无脑电图仪监测下渐进式大鼠脑死亡模型的建立

目的为研究供体脑死亡对供体外周器官的影响,建立一种无脑电图仪监测下渐进式大鼠脑死亡模型。探讨大鼠脑死亡模型制作要点、成功率以及血流动力学参数。方法57只Fisher大鼠行动脉插管、气管插管、诱导建立脑死亡模型,取肾前维持机械呼吸6h。将平均动脉压(MAP)>80mmHg的脑死亡大鼠,取其肾脏原位移植给Lewis大鼠。另外10只Fisher大鼠作为正常对照组供体。结果57只Fisher大鼠中45只(78.9%)在6h的机械性人工呼吸观察中,MAP始终在正常水平,可作为脑死亡供体。10只正常对照组大鼠,MAP虽呈下降趋势,但仍在正常水平。来自脑死亡大鼠的肾脏移植后再灌注时间(22±7)min与来自对照组的(5±3)min相比差异具有显著性(P<0.001)。其余12只大鼠被剔除出研究。结论无脑电图仪监测下,渐进式建立大鼠脑死亡模型,可达到与标准方法建立的脑死亡模型相似的保持正常血压的效果,可用于改善脑死亡供体器官质量和移植物功能。

Pathogenesis of hepatitis B virus infection

Infection with hepatitis B virus (HBV) leads to a wide spectrum of clinical presentations ranging from an asymptomatic carrier state to self-limited acute or fulminant hepatitis to chronic hepatitis with progression to cirrhosis and hepatocellular carcinoma. Infection with HBV is one of the most common viral diseases affecting man. Both viral factors as well as the host immune response have been implicated in the pathogenesis and clinical outcome of HBV infection. In this review, we will discuss the impact of virus-host interactions for the pathogenesis of HBV infection and liver disease. These interactions include the relevance of naturally occurring viral variants for clinical disease, the role of virus-induced apoptosis for HBV-induced liver cell injury and the impact of antiviral immune responses for outcome of infection.

Cooperative and Competitive Multi-Agent Systems:From Optimization to Games

Multi-agent systems can solve scientific issues related to complex systems that are difficult or impossible for a single agent to solve through mutual collaboration and cooperation optimization.In a multi-agent system,agents with a certain degree of autonomy generate complex interactions due to the correlation and coordination,which is manifested as cooperative/competitive behavior.This survey focuses on multi-agent cooperative optimization and cooperative/non-cooperative games.Starting from cooperative optimization,the studies on distributed optimization and federated optimization are summarized.The survey mainly focuses on distributed online optimization and its application in privacy protection,and overviews federated optimization from the perspective of privacy protection me-chanisms.Then,cooperative games and non-cooperative games are introduced to expand the cooperative optimization problems from two aspects of minimizing global costs and minimizing individual costs,respectively.Multi-agent cooperative and non-cooperative behaviors are modeled by games from both static and dynamic aspects,according to whether each player can make decisions based on the information of other players.Finally,future directions for cooperative optimization,cooperative/non-cooperative games,and their applications are discussed.

Surface air temperature changes over the Tibetan Plateau:Historical evaluation and future projection based on CMIP6 models

With its amplification simultaneously emerging in cryospheric regions,especially in the Tibetan Plateau,global warming is undoubtedly occurring.In this study,we utilized 28 global climate models to assess model performance regarding surface air temperature over the Tibetan Plateau from 1961 to 2014,reported spatiotemporal variability in surface air temperature in the future under four scenarios(SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5),and further quantified the timing of warming levels(1.5,2,and 3℃)in the region.The results show that the multimodel ensemble means depicted the spatiotemporal patterns of surface air temperature for the past decades well,although with differences across individual models.The projected surface air temperature,by 2099,would warm by 1.9,3.2,5.2,and 6.3℃relative to the reference period(1981–2010),with increasing rates of 0.11,0.31,0.53,and 0.70℃/decade under the SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5 scenarios for the period 2015–2099,respectively.Compared with the preindustrial periods(1850–1900),the mean annual surface air temperature over the Tibetan Plateau has hit the 1.5℃threshold and will break 2℃in the next decade,but there is still a chance to limit the temperature below 3℃in this century.Our study provides a new understanding of climate warming in high mountain areas and implies the urgent need to achieve carbon neutrality.

Transient demonstration of exciton behaviours in solid state cathodoluminescence under different driving voltage

In the solid state cathodoluminescence （SSCL）, organic materials were excited by hot electrons accelerated in silicon oxide （SiO2） layer under alternating current （AC）. In this paper exciton behaviours were analysed by using transient spectra under different driving voltages. The threshold voltages of SSCL and exciton ionization were obtained from the transient spectra. The recombination radiation occurred when the driving voltage went beyond the threshold voltage of exciton ionization. From the transient spectrum of two kinds of luminescence （exciton emission and recombination radiation）, it was demonstrated that recombination radiation should benefit from the exciton ionization.

Determinants of Farmers’ Perception of Climate Change: A Case Study from the Coastal Region of Bangladesh

Socio-economic conditions of farmers, especially in the coastal region in Bangladesh, have been severely affected because of climate change. This study was focused on analyzing the farmers’ perception of climate change by examining three vital issues: (1) description of the socioeconomic characteristics of farmers;(2) reporting on the perception of farmers experiences with climatic change;and (3) identification of the socio-economic factors associated with farmers’ perception of climate change. The study area encompasses three villages within the coastal region (Sathkhira district) of Bangladesh, a geographic region where climate change literature has highlighted as prone to accelerated degradation. A logit model, along with weighted indexes for ranking and descriptive statistics, was used to analyze the result of 100 farmers surveyed by questionnaire. We found that the majority of the farmers (88%) perceived changes in climatic conditions. Almost all farmers indicated increases in temperature, droughts, floods, cyclones, salinity level and decreasing rainfall over the last 20 years. The logit model explained that out of the nine factors surveyed;education, family size, farm size, family income, farming experiences and training received were significantly related and influential factors to perception of climate change. Therefore, government and non-governmental organizations are recommended to push forward with interventions, especially focusing on identified factors, in order to strengthen the farmers’ capacity to battle against climate change effects.

Monitoring of Temporal and Spatial Changes of Land Use and Land Cover in Metropolitan Regions through Remote Sensing and GIS

The use of remote sensing techniques and subsequent analysis by means of geographical information system (GIS) offers an effective method for monitoring temporal and spatial changes of landscapes. This work studies the urbanization processes and associated threats to natural ecosystems and resources in the metropolitan areas of Berlin and Erlangen-Fürth-Nürnber?Schwabach (EFNS). To compute the land use/cover (LULC) of the study areas, a supervised classification of “maximum likelihood” using Landsat data for the years of 1972, 1985, 1998, 2003, and 2015 is used. Results show that the built-up area is the dominant land use in both regions throughout the study period. This land use has increased at the expense of green and open areas in EFNS and at the expense of agricultural land in Berlin. Likewise, 5% of forest in EFNS is replaced with urban infrastructure. However, the amount of forest in Berlin increased by 3%. While EFNS experienced relatively big changes in its water bodies from 1972 to 1985, changes in water bodies in Berlin were rather slight during the last 40 years. The overall accuracy of our remotely sensed LULC maps was between 88% and 94% in Berlin and between 85.87% and 87.4% for EFNS. The combination of remote sensing and GIS appears to be an indispensable tool for monitoring changes in LULC in urban areas and help improving LU planning to avoid environmental and ecological problems.

Chemical Sensitivity of Luminescent Epitaxial Surface InP Quantum Dots

Surface InP quantum dots grown by gas source molecular beam epitaxy on In0.48Ga0.52P buffer layer lattice matched to GaAs substrate shows a broad-band near-infrared photoluminescence ranging from 750 to 865 nm dependent on their dimensions. A reversible luminescence intensity enhancement has been observed when the quantum dots were exposed to vapours of different chemical solvents with the highest sensitivity for alcohol (methanol and ethanol) vapours. The luminescent behaviour is dependent on the solvent type and concentration. The peak energy and band shape of the luminescence are not affected by the solvent vapour.

Fibrin sealant for esophageal anastomosis:A phase II study

BACKGROUND Esophagectomy is a pivotal curative modality for localized esophageal or esophagogastric junction cancer(EC or EJC).Postoperative anastomotic leakage(AL)remains problematic.The use of fibrin sealant(FS)may improve the strength of esophageal anastomosis and reduce the incidence of AL.AIM To assess the efficacy and safety of applying FS to prevent AL in patients with EC or EJC.METHODS In this single-arm,phase II trial(Clinicaltrial.gov identifier:NCT03529266),we recruited patients aged 18-80 years with resectable EC or EJC clinically staged as T1-4aN0-3M0.An open or minimally invasive McKeown esophagectomy was performed with a circular stapled anastomosis.After performing the anastomosis,2.5 mL of porcine FS was applied circumferentially.The primary endpoint was the proportion of patients with AL within 3 mo.RESULTS From June 4,2018,to December 29,2018,57 patients were enrolled.At the data cutoff date(June 30,2019),three(5.3%)of the 57 patients had developed AL,including two(3.5%)with esophagogastric AL and one(1.8%)with gastric fistula.The incidence of anastomotic stricture and other major postoperative complications was 1.8%and 17.5%,respectively.The median time needed to resume oral feeding after operation was 8 d(Interquartile range:7.0-9.0 d).No adverse events related to FS were recorded.No deaths occurred within 90 d after surgery.CONCLUSION Perioperative sealing with porcine FS appears safe and may prevent AL after esophagectomy in patients with resectable EC or EJC.Further phase III studies are warranted.

Quantifying the parameter dependent basin of the unsafe regime of asymmetric Lévy-noise-induced critical transitions

In real systems,the unpredictable jump changes of the random environment can induce the critical transitions(CTs)between two non-adjacent states,which are more catastrophic.Taking an asymmetric Lévy-noise-induced tri-stable model with desirable,sub-desirable,and undesirable states as a prototype class of real systems,a prediction of the noise-induced CTs from the desirable state directly to the undesirable one is carried out.We first calculate the region that the current state of the given model is absorbed into the undesirable state based on the escape probability,which is named as the absorbed region.Then,a new concept of the parameter dependent basin of the unsafe regime(PDBUR)under the asymmetric Lévy noise is introduced.It is an efficient tool for approximately quantifying the ranges of the parameters,where the noise-induced CTs from the desirable state directly to the undesirable one may occur.More importantly,it may provide theoretical guidance for us to adopt some measures to avert a noise-induced catastrophic CT.

THE OVERLOOKED ECOSYSTEM DRIVING FORCE IN NON-EUTROPHICATED FRESHWATER SYSTEMS:DISSOLVED HUMIC SUBSTANCES-A SHORT REVIEW AND OUTLOOK

This review starts with the description of the quantitative significance of dissolved organic material in general and dissolved humic substances (HS) in particular in various ecosystems. Despite their high quantities, the knowledge about the role of HS is still very low and full of old, but still recycled paradigms. HS are thought to be inert or at least refractory and too large to be taken up by aquatic organisms. Instead, I present evidence that dissolved HS that mainly derives from the terrestrial environment, are taken up and directly and/or indirectly interfere with freshwater organisms and, thus, structure biocenoses. Relatively well known is in the meantime the fuelling function of allochthonous HS, which, upon irradiation, release fatty acids, which serve as substrates for microbial growth. This is an indirect effect of HS. Microbes, in turn, are food for mixotrophic algae and (heterotrophic) zooplankton. Thus, non-eutrophicated freshwaters are net-heterotrophic, meaning that respiration exceeds primary production. Furthermore, model calculations exemplify that only a very small portion of the terrestrial production is sufficient to cause net-heterotrophy in these freshwater bodies. But, recent papers show also that due to different stoichiometries the maximal plankton biomass production with algae or mixotrophs is higher than with bacteria. Very recently, several direct effects of HS have been elucidated. Among them are:induction of chaperons (stress shock proteins), induction and modulation of biotransformation enzymes, modulation (mainly inhibition) of photosynthetic oxygen release of aquatic plants, production of an internal oxidative stress, modulation of the offspring numbers in the nematode Caenorhabditis elegans[WTBZ], feminization of fish and amphibs, interference within the thyroid system, and action as chemical attractant to C. elegans. We are still in the phase of identifying the various physiological, biochemical, and molecular-biological effects. Hence, the ecological and ecophysiological significance of these HS-mediated effects still remain somewhat obscure. Nevertheless, HS appear generally to have an impact on the individual as well as on the community and even ecosystem level comparable to that of, for instance, nutrients.

雌性斑胸草雀发育和成体期发声核团LMAN中神经元数量的高水平维持(英文)

鸟类的发声和发声学习涉及处于脑中不同水平的相互联系的一些发声核团。在很多鸟类中, 仅雄性鸣啭, 例如在斑胸草雀(Taeniogygia guttata) 中, 雌雄个体间存在显著的性差异, 雌性发声系统和发声核团中的神经元数量显著少于雄性。推测这种性差异也可能存在于弓状皮质前部大细胞外侧核(LMAN), 但有关这方面的报道还很少。为探讨雌雄鸣禽脑中神经元数量发育的规律, 我们应用半薄切片对斑胸草雀发育不同阶段的神经元数量和密度的变化进行了数量分析。结果表明, 在全部实验组中, 发育10 d和成体雌性LMAN中神经元的密度和神经元数量均无明显变化, 神经元的数量维持在一个较高水平。在雄鸟中, 我们发现在发育早期神经元的数量有极为显著的减少, 这与已有的报道, 即应用非类固醇技术获得的结果相似。LMAN中神经元数量的减少(57%) 一直持续到成体。因此, 成年雌鸟LMAN中的全部神经元数量是雄鸟的4 倍(P<0 001)。推测雌鸟脑中存在较多的神经元数量可能与其在发育和成体期间需维持适当的神经网络有关, 这种神经构筑对于动物种间识别等功能可能具有特殊意义。

Data-Driven Discovery of Stochastic Differential Equations

Stochastic differential equations(SDEs)are mathematical models that are widely used to describe complex processes or phenomena perturbed by random noise from different sources.The identification of SDEs governing a system is often a challenge because of the inherent strong stochasticity of data and the complexity of the system’s dynamics.The practical utility of existing parametric approaches for identifying SDEs is usually limited by insufficient data resources.This study presents a novel framework for identifying SDEs by leveraging the sparse Bayesian learning(SBL)technique to search for a parsimonious,yet physically necessary representation from the space of candidate basis functions.More importantly,we use the analytical tractability of SBL to develop an efficient way to formulate the linear regression problem for the discovery of SDEs that requires considerably less time-series data.The effectiveness of the proposed framework is demonstrated using real data on stock and oil prices,bearing variation,and wind speed,as well as simulated data on well-known stochastic dynamical systems,including the generalized Wiener process and Langevin equation.This framework aims to assist specialists in extracting stochastic mathematical models from random phenomena in the natural sciences,economics,and engineering fields for analysis,prediction,and decision making.

Influence of gene modified (IL-7, IL-4 and B7) tumor cell vaccines on tumor antigen presentation

We have previously shown that tumor cellsgenetically modified to co-express IL-4 or IL-7 and B7.1have increased immunogenicity and provided vaccinessuperior to single gene transfectants or tumor cells/adjuvant mixture.Tumor antigens can be presented eitherdirectly by tumor cells or be indirectly represented byhost APC(cross-priming).Here we asked whether B7.1and IL-7 or IL-4 improved in an additive fashion one pathway of antigen presentation or complemented each other by improving preferentially different pathways of antigen presentation.

Lessons Learned and Future Challenges for Integrated and Participatory Approaches to Mountain Research——Conclusions from the Mountain Symposium and this Special Issue

The International Symposium ‘Towards Sustainable Livelihoods and Ecosystems in Mountainous Regions＇, held in Chiang Mai from 7-9 March 2006 （hereafter referred to as ‘Mountain Symposium＇）, brought together a wealth of experience from mountain research and development in four continents. Some of its highlights are presented in this Special Issue. If one were to choose a ＇leitmotif that would best capture the present state of knowledge in mountain research, it would be recognizing heterogeneity, complexity, interdependency, and learning how to deal with it. We are in the middle of a learning process and it is important to remember Rod Lefroy＇s statement in the panel discussion of the Mountain Symposium： ＂perfection is the enemy of progress＂ （Lefroy 2006）.