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The paper is to learn the experience in the field of Manned/Unmanned Aerial Vehicle (MUAV) cooperative technology and enlighten the technology development and progress of our country. First of all, it is to collect the typical research projects and tracke experiment dynamic, excavate the development in the field of MUAV cooperative technology route; And then, attention is paid to the related typical application cases to analyze the current technical maturity; Second, from the perspective of technology development, application, analysis is executed from the human-computer interaction control technology, intelligent decisionmaking technology, communication anti-jamming technology, open hardware and software technology to MUAV; Finally, the experience of the U.S. military in the field of MUAV collaborative technology are summarized, and the enlightenment for the development of China in the field is given. [ABSTRACT FROM AUTHOR]

With the continuous progress of information technique, assisted driving technology has become an effective technique to avoid traffic accidents. Due to the complex road conditions and the threat of vehicle information being attacked and tampered with, it is difficult to ensure information security. This paper uses blockchain to ensure the safety of driving information and introduces mobile edge computing technology to monitor vehicle information and road condition information in real time, calculate the appropriate speed, and plan a reasonable driving route for the driver. To solve these problems, this paper proposes a trusted edge resource allocation framework for assisted driving service, which includes two stages: the blockchain generation stage (the first stage) and assisted driving service stage (the second stage). Furthermore, in the first stage, a delay-and-throughput-oriented block generation model for the mobile terminal is designed. In the second stage, a balanced offloading algorithm for assisted driving service based on edge collaboration is proposed to solve the problems of unbalanced load of cluster mobile edge computing (MEC) servers and low resource utilization of the system. And this paper optimizes the throughput of blockchain and delay of the transportation network through deep reinforcement learning (DRL) algorithm. Finally, compared with joint computation and communication resources' allocation (JCCR) and resource allocation method based on binary offloading (RAB), our proposed scheme can optimize the delay by 7.4% and 26.7%, and support various application services of the vehicular networks more effectively. [ABSTRACT FROM AUTHOR]

Clouds are an important parameter of artificial water augmentation, which are of substantial significance to judge the precipitation capacity. Xinjiang is an arid region in Northwest China, where weather stations are sparsely distributed, the types of underlying surface are complex and the climate difference between southern and northern Xinjiang varies greatly. However, the retrieval of the total cloud cover (TCC) from satellite in arid areas is a challenging task. Based on the hourly data of TCC observed by ground observation stations from June 2015 to May 2016, considered the complex underlying surfaces and different weather conditions, the precision, consistency and error between the cloud total amount products of FengYun-2F stationary satellite (FY-2F/CTA) and manually observed TCC are compared and evaluated in Xinjiang region. The findings of this study are as follows: (1) The precision rate (PR) of FY-2F/CTA in Xinjiang region is 74.6 %, which gradually decreases from north to south, demonstrating a high false rate (FR) and a low missing rate (MR); The consistency rate (CR) is 51.5 %, with little difference among three sub-regions of Xinjiang, all showing high weak rate (WR) and low strong rate (SR), which means that the TCC inverted from FY-2 satellite data are generally lower than that observed by ground observation stations, especially in Southern Xinjiang; The Bias is -20 %, and all the error indexes (EIs) including Bias, AE and RMSE increase from central to the north and south of Xinjiang, that means the EIs are the lowest in Tianshan Mountains, and the highest in Southern Xinjiang. The PR and CR of FY-2F/CTA in the vegetation underlying surface are better than those of non-vegetation, that is to say, FY-2F/CTA have the best identification effect on the forest and plowland underlying surfaces, and the worst effect on the snow and ice underlying surface. (2) With the increase of temperature, the PR and CR of FY-2F/CTA increase, while the EIs decrease; Under various temperature conditions, FY-2F/CTA have always been exhibiting high MR, low FR (on the contrary in January), high WR and low SR. From low elevation to high elevation, the PR and CR of FY-2F/CTA decrease, but the PR increases significantly when the altitude is higher than 2000 m. (3) Dust reduces the CR of FY-2F/CTA, increases the SR, but it has little effect on the identification of cloud and non-cloud. (4) Under different cloud cover levels, the PR and EIs of FY-2F/CTA are proportional to the amount of TCC, while the CR is inversely proportional to it, that is, the CR is higher, the PR and EIs are lower under clear sky and partly cloudy conditions, and the CR is lower, the PR and EIs are higher under cloudy and overcast conditions. This study is the first to evaluate the FY-2F/CTA on the scales of complex underlying surface, various temperature and altitude, dust effects and different cloud cover levels in arid areas of Xinjiang. Thus, the results would provide an important reference for satellite retrieval and application of TCC in arid areas. [ABSTRACT FROM AUTHOR]

Background: Predicting which preschool children with recurrent wheezing (RW) will develop school-age asthma (SA) is difficult, highlighting the critical need to clarify the pathogenesis of RW and the mechanistic relationship between RW and SA. Despite shared environmental exposures and genetic determinants, RW and SA are usually studied in isolation. Based on network analysis of nasal and tracheal transcriptomes, we aimed to identify convergent transcriptomic mechanisms in RW and SA. Methods: RNA-sequencing data from nasal and tracheal brushing samples were acquired from the Gene Expression Omnibus. Combined with single-cell transcriptome data, cell deconvolution was used to infer the composition of 18 cellular components within the airway. Consensus weighted gene co-expression network analysis was performed to identify consensus modules closely related to both RW and SA. Shared pathways underlying consensus modules between RW and SA were explored by enrichment analysis. Hub genes between RW and SA were identified using machine learning strategies and validated using external datasets and quantitative reverse transcription-polymerase chain reaction (qRTPCR). Finally, the potential value of hub genes in defining RW subsets was determined using nasal and tracheal transcriptome data. Results: Co-expression network analysis revealed similarities in the transcriptional networks of RW and SA in the upper and lower airways. Cell deconvolution analysis revealed an increase in mast cell fraction but decrease in club cell fraction in both RW and SA airways compared to controls. Consensus network analysis identified two consensus modules highly associated with both RW and SA. Enrichment analysis of the two consensus modules indicated that fatty acid metabolism-related pathways were shared key signals between RW and SA. Furthermore, machine learning strategies identified five hub genes, i.e., CST1, CST2, CST4, POSTN, and NRTK2, with the up-regulated hub genes in RW and SA validated using three independent external datasets and qRT-PCR. The gene signatures of the five hub genes could potentially be used to determine type 2 (T2)-high and T2- low subsets in preschoolers with RW. Conclusions: These findings improve our understanding of the molecular pathogenesis of RW and provide a rationale for future exploration of the mechanistic relationship between RW and SA. [ABSTRACT FROM AUTHOR]

Asthma is the most common chronic condition among children; however, the underlying molecular mechanism remains unclear. Dysregulated immune response and different infiltration states of immune cells are critical for asthma pathogenesis. Here, three childhood asthma gene expression datasets were used to detect key genes, immune cells, and pathways involved in childhood asthma. From these datasets, 33 common differentially expressed genes (DEGs) were identified, which showed enrichment in the T helper 1 (Th1) and T helper 2 (Th2) cell differentiation pathway and the T helper 17 (Th17) cell differentiation pathway. Using the weighted gene co-expression network analysis (WGCNA), CD3D and CD3G were identified as key genes closely correlated with childhood asthma. Upregulation of CD3D and CD3G was further validated in bronchoalveolar lavage cells from childhood asthmatics with control individuals by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The immune cell infiltration analysis indicated that CD3D and CD3G were negatively correlated with increased resting mast cells and eosinophils, and highly correlated with several cell markers of Th1, Th2, and Th17 cells. In addition, we found that CD3D and CD3G were closely related to the Th1 and Th2 cell differentiation pathway and the Th17 cell differentiation pathway. Our results reveal the important roles of two key genes and immune infiltration in the pathogenesis of childhood asthma. Thus, this study provides a new perspective for exploring potential molecular targets for childhood asthma treatment. [ABSTRACT FROM AUTHOR]

Non-methane short-lived climate forcers (SLCFs), including aerosols, ozone, and their precursors, are important climate forcings and primary air pollutants. Stringent SLCF emissions controls to mitigate air pollution have been implemented by various governments, which will substantially impact the future climate. We investigate the changes in future climate extremes and resulting population exposure risks in Asia during 2031-2050 in response to non-methane SLCF emissions reductions using multi-model ensemble (MME) simulations under two scenarios (SSP3-7.0 and SSP3-7.0-lowNTCF) with different air quality control measures from the Aerosol and Chemistry Model Intercomparison Project (AerChemMIP), which is endorsed by Coupled Model Intercomparison Project phase 6 (CMIP6). The MME results show that future reductions in non-methane SLCF emissions lead to an increase of 0.23 W m-2 in global annual mean effective radiative forcing, thereby magnifying the greenhouse gas (GHG)-induced global surface warming by 0.19 K during 2031-2050. The additional warming caused by the non-methane SLCF reductions increases the regional average temperature on the hottest days (TXx) by 0.3 K, the percentage of warm days (TX90p) by 4.8%, the number of tropical nights (TR) by 1.7 days, the warm spell duration (WSDI) by 1.0 days, the number of heavy precipitation days (R10) by 1.3 days, the maximum consecutive 5-day precipitation (RX5day) by 0.8 mm, and the total wet-day precipitation (R95p) by 16.4 mm during 2031-2050. For temperature extremes, the largest regional increases of TXx, TX90p, and WSDI occur in northern India (NIN) and northern China (NC). Relatively large increases in TR are predicted in NC and the Sichuan Basin (SCB), reaching 5.1 days and 4.9 days, respectively. For precipitation extremes, the regional changes are greatest in southern China (SC), particularly southwestern China (SWC), where reductions of non-methane SLCF emissions increases R10 by 3.0 days, RX5day by 2.2 mm, and R95p by 39.5 mm. Moreover, the populations exposed to temperature and precipitation extremes increase most sharply in NIN, reaching (32.2 ± 11.4) × 107 person-days and (6.7 ± 7.8) × 106 person-days during 2031-2050, respectively, followed by NC and SCB. Our results highlight the significant impacts of non-methane SLCF reductions on future climate extremes and related exposure risks in Asia, which are comparable to the impact associated with increased GHG forcing in some regions. [ABSTRACT FROM AUTHOR]

With the development of internet of vehicles, the traditional centralized content caching mode transmits content through the core network, which causes a large delay and cannot meet the demands for delay-sensitive services. To solve these problems, on basis of vehicle caching network, we propose an edge collaborative caching scheme. Road side unit (RSU) and mobile edge computing (MEC) are used to collect vehicle information, predict and cache popular content, thereby provide low-latency content delivery services. However, the storage capacity of a single RSU severely limits the edge caching performance and cannot handle intensive content requests at the same time. Through content sharing, collaborative caching can relieve the storage burden on caching servers. Therefore, we integrate RSU and collaborative caching to build a MEC-assisted vehicle edge collaborative caching (MVECC) scheme, so as to realize the collaborative caching among cloud, edge and vehicle. MVECC uses deep reinforcement learning to predict what needs to be cached on RSU, which enables RSUs to cache more popular content. In addition, MVECC also introduces a mobility-aware caching replacement scheme at the edge network to reduce redundant cache and improving cache efficiency, which allows RSU to dynamically replace the cached content in response to the mobility of vehicles. The simulation results show that the proposed MVECC scheme can improve cache performance in terms of energy cost and content hit rate. [ABSTRACT FROM AUTHOR]

Quantifying the influences of land use/cover (LULC) change on hydrological processes is important for rational utilization of water resources. The objective of this study was to evaluate the impacts of spatiotemporal LULC change on hydrological components in a typical agricultural area located in the North China Plain at both basin and sub-basin scales. LULC change was quantified, and the Soil and Water Assessment Tool was optimized using parameters associated with LULC conditions. We concluded that the urban and forest areas increased by 25.57 and 10.56%, with the cropland area decreased by 36.76%. About half of the surface runoff (SURQ) in the basin was generated from the urban area, with the SURQ increased significantly in the upstream and downstream of the basin where overlapped with urbanized areas. The proportions of evapotranspiration generated by cropland and forest areas increased slightly (0.89 and 0.55%, respectively), especially in sub-basins where the conversion of cropland to forest was obvious. Urban, forest, and cropland were the main types that generated water yield (WYLD). The proportion of WYLD generated on the urban area increased by 9.55% and decreased in other areas, which may be related to the combined effects of urbanization and forest reduction. [ABSTRACT FROM AUTHOR]

With the continuous development of the Internet, the domain name system (DNS) as infrastructure is playing an increasingly important role. However, traditional DNS architecture is centralized, and there are some security problems such as the right concentration and power abuse. This paper combines blockchain technology with DNS technology and proposes a domain name service model based on the permissioned blockchain. At first, this paper designs a top-level domain chain (TLDChain) model to conduct consensus on block transactions and achieve decentralization of domain name service. Then, this paper introduces a data model to upload data. At the same time, to improve the efficiency of the blockchain data query, this paper proposes a data warehouse to speed up the query. Also, it designs the domain name data synchronization algorithm and consistency checking algorithm to achieve synchronization and quick consistency checking of domain name data. At last, this paper introduces the domain name resolution process of this model. Experimental results show that the proposed DNS service model not only realizes the decentralization of domain name resolution but also improves query efficiency. [ABSTRACT FROM AUTHOR]

This paper examines the gendered impacts of the COVID-19 pandemic on the Chinese migrants who had returned to their hometowns for the Spring Festival before the Wuhan lockdown, using data from a recent nationally representative survey. The study finds that women migrants were less likely than men migrants to return to the cities and also less likely to return to paid work after the pandemic outbreak. It also finds that having a preschool-age child had a strong negative effect on women migrants' employment decisions, but it had no effect on men migrants' decisions. These results expand the literature on the economic vulnerabilities of Chinese migrant workers. More importantly,~the findings indicate that the COVID-19 pandemic has caused a setback in the~progress made in pre-pandemic times in advancing Chinese rural women's position in the labor market. HIGHLIGHTS The COVID-19 pandemic had negative employment consequences for Chinese migrant workers. Women migrants were the hardest hit and more likely to withdraw from migration flows and paid work. Women's caregiving roles and employment in face-to-face services are the main causes of their withdrawal. The pandemic has reinforced traditional gender roles and heightened labor market inequalities. [ABSTRACT FROM AUTHOR]

El Niño is a complex system with diverse distribution features and intensities. The regional climate anomalies caused by different types of El Niño event likely lead to various impacts on winter haze pollution in China. Based on long-term site observations of haze days in China from 1961 to 2013, this study explores the effects of Eastern Pacific (EP) and Central Pacific (CP) types of El Niño event on winter haze days (WHD) in China's Jing-Jin-Ji (JJJ) region and the physical mechanisms underlying WHD changes. The results show statistically significant positive and negative correlations, respectively, between WHD in the JJJ region and EP and CP El Niño events. At most sites in the JJJ region, the average WHD are increased in all EP El Niño years, with the maximum change exceeding 2.0 days. Meanwhile the average WHD are decreased at almost all stations over this region in all CP El Niño years, with the largest change being more than -2.0 days. The changes in large-scale circulations indicate obviously positive surface air temperature (SAT) anomalies and negative sea level pressure (SLP) anomalies over North China, and southerly wind anomalies at the mid-low troposphere over eastern China in the winters of EP El Niño years. These anomalies are conducive to increases in WHD in the JJJ region. However, there are significant northerly and northwesterly wind anomalies at the mid-low troposphere over eastern China, and stronger and wider precipitation anomalies in the winters of CP El Niño years, which contribute to decreased WHD over the JJJ region. Changes in local synoptic conditions indicate negative SLP anomalies, positive SAT anomalies, and weakened northerly winds over the JJJ region in the winters of EP El Niño years. The occurrence frequency of circulation types conducive to the accumulation (diffusion) of aerosol pollutants is increased (decreased) by 0.4 % (0.37 %) in those winters. However, the corresponding frequency is decreased (increased) by 0.54 % (0.56 %) in the winters of CP El Niño years. Our study highlights the importance of distinguishing the impacts of two types of El Niño events on winter haze pollution in China's JJJ region. [ABSTRACT FROM AUTHOR]

To mitigate the projected global warming in the 21st century, it is well recognized that society needs to cut CO2 emission and other short-lived warming agents aggressively. However, to stabilize the climate at a warming level closer to the present day, such as the "well below 2 °C" aspiration in the Paris agreement, a net-zero carbon emission by 2050 is still insufficient. The recent IPCC special report calls for a massive scheme to extract CO2 directly from the atmosphere, in addition to the decarbonization, to reach negative net emission at the mid-century mark. Another ambitious proposal is the solar radiation-based geoengineering schemes, including injecting sulfur gas into the stratosphere. Despite being in the public debate for years, these two leading geoengineering schemes have not been carefully examined under a consistent numerical modeling framework. Here we present a comprehensive analysis of climate impacts of these two geoengineering approaches using two recently available large-ensemble (> 10 members) model experiments conducted by a family of state-of-art Earth system models. The CO2 -based mitigation simulation is designed to include both emissions cut and carbon capture. The solar radiation-based mitigation simulation is designed to inject the sulfur gas strategically at specified altitudes and latitudes and run a feedback control algorithm, to avoid common problems previously identified such as the over-cooling of the Tropics and large-scale precipitation shifts. Our analysis focuses on the projected aridity conditions over the Americas in the 21st century, in detailed terms of the mitigation potential, the temporal evolution, the spatial distribution (within North and South America), the relative efficiency, and the physical mechanisms. We show that sulfur injection, in contrast to previous notions of leading to excessive terrestrial drying (in terms of precipitation reduction) while offsetting the global mean greenhouse gas (GHG) warming, will instead mitigate the projected drying tendency under RCP8.5. The surface energy balance change induced by Sulfur injection, in addition to the well-known response in temperature and precipitation, plays a crucial role in determining the overall terrestrial hydroclimate response. However, when normalized by the same amount of avoided global warming, in these simulations, sulfur injection is less effective in limiting the worsening trend of regional land aridity in the Americas, when compared with carbon capture. Temporally, the climate benefit of Sulfur injection will emerge more quickly, even when both schemes are hypothetically started in the same year of 2020. Spatially, both schemes are effective in curbing the drying trend over North America. However, for South America, the Sulfur Injection scheme is particularly more effective for the sub-Amazon region (South Brazil), while the Carbon Capture scheme is more effective for the Amazon region. We conclude that despite the apparent limitations (such as inability to address ocean acidification) and potential side effects (such as changes to the ozone layer), innovative means of Sulfur Injection should continue to be explored as a potential low-cost option in the climate solution toolbox, complementing other mitigation approaches such as emissions cut and carbon capture (Cao et al., 2017). Our results demonstrate the urgent need for multi-model comparison studies and detailed regional assessment in other parts of the world. [ABSTRACT FROM AUTHOR]

By analyzing the force relationship model of wave high speed impact on surfer ankle and ankle complex model, the design of motion complex model under high speed wave impact promotes surfer to give full play to his body function. Improve the performance of surfing events at sea. In this paper, a dynamic analysis model of surfer ankle complex model based on multi-dimensional motion feature decomposition and body structure reconstruction is proposed, and the influence of wave high speed impact on surfer ankle complex model is analyzed. Firstly, the kinematic relationship model of ankle-ankle complex model of surfer is constructed, and the muscle movement space of 7 degrees of freedom of surfer's lower extremity is reconstructed. The mechanical model of surfer ankle and ankle complex model induced by high speed wave shock is analyzed, and the dynamic response model is improved. The simulation results show that the model can accurately reflect the movement characteristics of the ankle-ankle complex model of surfers by using the model to analyze the effect of high-speed wave shock on the activities of surfer ankle-ankle complex model. The optimal arrangement of ankle and ankle joint under the high speed impact of waves can effectively improve the sports effect and performance of surfers. [ABSTRACT FROM AUTHOR]

The Community Atmosphere Model version 6 (CAM6) released in 2018, as part of the Community Earth System Model version 2 (CESM2) modeling framework, is a major upgrade over the previous CAM5 that has been used in numerous global and regional climate studies in the past six years. Since CESM2/CAM6 will participate in the upcoming Coupled Model Intercomparison Project phase 6 (CMIP6) and is likely to be adopted in many future studies, its simulation fidelity needs to be thoroughly examined. Here we evaluate the performance of a developmental version of the Community Atmosphere Model with parameterizations that will be used in CMIP6 (CAM6α) with the default 1° horizontal resolution (0.9° × 1.25°, CAM6α-1°) and a higher resolution simulation (approximately 0.25°, CAM6α-0.25°), against various precipitation observational datasets over Asia. The CAM6α performance is also compared with CAM5 with the default 1° horizontal resolution (CAM5-1°). With the prognostic treatment of precipitation processes (which is missing in CAM5) and the new microphysics module, CAM6 is able to better simulate climatological mean and extreme precipitation over Asia, to better capture the heaviest precipitation events, to reproduce the diurnal cycle of precipitation rates over most of Asia, and to better simulate the probability density distributions of daily precipitation over Tibet, Korea, Japan and Northern China. Higher horizontal resolution in CAM6α improves simulations of mean and extreme precipitation over mountainous Sichuan and Northern China, but the performance degrades over the Maritime continent. Further diagnosis on moisture budget suggests that the physical processes leading to model improvement are different over different regions. Both upgraded physical parameterizations and higher horizontal resolution affect the precipitation response to internal variability of ocean and atmosphere (e.g. Asian monsoon index, ENSO, PDO), but the effects vary across different regions. Higher horizontal resolution degrades the model performance in simulating precipitation variability associated with the East Asian summer monsoon in the middle and lower reaches of the Yangtze River in China. The precipitation variability associated with ENSO gets better with upgraded physical parameterizations and higher horizontal resolution. Higher horizontal resolution, however, induces an opposite response to PDO in CAM6 over Southern China. [ABSTRACT FROM AUTHOR]

Objective: To examine the frequency and clinical features of excessive daytime sleepiness (EDS) and its association with cognitive and behavioural impairments in patients with amyotrophic lateral sclerosis (ALS).Methods: We conducted a cross-sectional investigation to explore the frequency and clinical features of EDS in a group of 121 Chinese patients with ALS compared with 121 age-matched and sex-matched healthy subjects. EDS was diagnosed using the Epworth Sleepiness Scale (ESS). Other characteristics of patients with ALS including sleep quality, REM sleep behaviour disorder (RBD), restless legs syndrome (RLS), cognition, behaviour, depression and anxiety were also evaluated.Results: EDS was significantly more frequent in patients with ALS than in controls (26.4% vs 8.3%; p<0.05). Patients with ALS with EDS scored lower scores on the revised ALS Functional Rating Scale (ALSFRS-R), Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and MMSE and MoCA delayed memory subitems and higher on the Frontal Behavioural Inventory (FBI) than patients with ALS without EDS. ESS scores correlated with global ALSFRS-R, FBI, MMSE and MoCA scores and MMSE and MoCA delayed memory scores. RLS and global ALSFRS-R scores were independently associated with EDS in patients with ALS.Conclusions: We identified a high frequency of EDS symptoms in Chinese patients with ALS, and these patients might have more serious physical, cognitive and frontal behaviour impairment. Patients with ALS might improve quality of life from the timely recognition and optimised management of EDS symptoms. Our results further suggest that ALS is a heterogeneous disease that might exhibit abnormal sleep-wake patterns. [ABSTRACT FROM AUTHOR]

Three-dimensional bicontinuous open (3DBO) nanoporosity has been recognized as an important nanoarchitecture for catalysis, sensing, and energy storage. Dealloying, i.e., selectively removing a component from an alloy, is an efficient way to fabricate nanoporous materials. However, current electrochemical and liquid-metal dealloying methods can only be applied to a limited number of alloys and usually require an etching process with chemical waste. Here, we report a green and universal approach, vapor-phase dealloying, to fabricate nanoporous materials by utilizing the vapor pressure difference between constituent elements in an alloy to selectively remove a component with a high partial vapor pressure for 3DBO nanoporosity. We demonstrate that extensive elements, regardless of chemical activity, can be fabricated as nanoporous materials with tunable pore sizes. Importantly, the evaporated components can be fully recovered. This environmentally friendly dealloying method paves a way to fabricate 3DBO nanoporous materials for a wide range of structural and functional applications. [ABSTRACT FROM AUTHOR]

Tuning surface structures by bottom-up synthesis has been demonstrated as an effective strategy to improve the catalytic performances of nanoparticle catalysts. Nevertheless, the surface modification of three-dimensional nanoporous metals, fabricated by a top-down dealloying approach, has not been achieved despite great efforts devoted to improving the catalytic performance of three-dimensional nanoporous catalysts. Here we report a surfactant-modified dealloying method to tailor the surface structure of nanoporous gold for amplified electrocatalysis toward methanol oxidation and oxygen reduction reactions. With the assistance of surfactants, {111} or {100} faceted internal surfaces of nanoporous gold can be realized in a controllable manner by optimizing dealloying conditions. The surface modified nanoporous gold exhibits significantly enhanced electrocatalytic activities in comparison with conventional nanoporous gold. This study paves the way to develop high-performance three-dimensional nanoporous catalysts with a tunable surface structure by top-down dealloying for efficient chemical and electrochemical reactions. [ABSTRACT FROM AUTHOR]

We examine the roles of fast and slow responses in shaping the total equilibrium response of the East Asian summer monsoon (EASM) to reflecting (sulfate, SO4/ and absorbing (black carbon, BC) aerosol forcings over the industrial era using the Community Earth System Model version 1 (CESM1). Our results show that there is a clear distinction between fast and slow responses of the EASM to aerosol forcings and the slow climate response due to aerosol-induced change in sea surface temperature (SST) plays an important role in the impacts of aerosols on the EASM. The EASM is weakened by a decrease in land-sea surface thermal contrast in the fast response (FR) component to SO4 forcing, whereas the weakening is more intensive due to the changes in tropospheric thermodynamic and dynamic structures in the slow response (SR) component to SO4. The total climate adjustment caused by SO4 is a significant weakening of the EASM and a decrease in precipitation. The BC-induced fast adjustment strengthens the EASM both by increasing the local land-sea surface thermal contrast and shifting the East Asian subtropical jet (EASJ) northwards. The BC-induced slow climate adjustment, however, weakens the EASM through altering the atmospheric temperature and circulation. Consequently, the EASM is slightly enhanced, especially north of 30° N, in the total response (TR) to BC. The spatial patterns of precipitation change over East Asia due to BC are similar in the total response and slow response. This study highlights the importance of ocean response to aerosol forcings in driving the changes of the EASM. [ABSTRACT FROM AUTHOR]

We examine the roles of fast and slow responses in shaping the total equilibrium response of the East Asian summer monsoon (EASM) to reflecting (sulfate, SO4) and absorbing (black carbon, BC) aerosol forcings over the industrial era using the Community Earth System Model version 1. Our results show that there is a clear distinction between fast and slow responses of the EASM to aerosol forcings and the slow climate response due to aerosol-induced change in sea surface temperature plays an important role in the impacts of aerosols on the EASM. The EASM is weakened by a decrease in land-sea surface thermal contrast in the fast response component to SO4 forcing, whereas the weakening is more intensive by the changes in tropospheric thermodynamic and dynamic structures in the slow response component to SO4. The total climate adjustment caused by SO4 is a significant weakening of the EASM and a decrease in precipitation. The BC-induced fast adjustment strengthens the EASM both by increasing the local surface land-sea thermal contrast and shifting the East Asian subtropical jet northwards. BC-induced slow climate adjustment, however, weakens the EASM through altering the atmospheric temperature and circulation. Consequently, the EASM is enhanced north of 30°â€‰N but slightly reduced south of 30°â€‰N in the total response to BC. The spatial patterns of precipitation change over East Asia due to BC are similar in total response and slow response. This study highlights the importance of ocean response to aerosol forcings in driving the changes of the EASM. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the study which aims to identify cerebrovascular events in patients with vertigo or dizziness.

Open-celled aluminum foams with different pore sizes were fabricated. A plasma electrolytic oxidation (PEO) treatment was applied on the aluminum foams to create a layer of ceramic coating. The sound absorption coefficients of the foams were measured by an impedance tube and they were calculated by a transfer function method. The experimental results show that the sound absorption coefficient of the foam increases gradually with the decrease of pore size. Additionally, when the porosity of the foam increases, the sound absorption coefficient also increases. The PEO coating surface is rough and porous, which is beneficial for improvement in sound absorption. After PEO treatment, the maximum sound absorption of the foam is improved to some extent. [ABSTRACT FROM AUTHOR]

Realization of open online control of diverse in-situ sensors is a challenge. This paper proposes a Cyber-Physical Geographical Information Service-enabled method for control of diverse in-situ sensors, based on location-based instant sensing of sensors, which provides closed-loop feedbacks. The method adopts the concepts and technologies of newly developed cyber-physical systems (CPSs) to combine control with sensing, communication, and computation, takes advantage of geographical information service such as services provided by the Tianditu which is a basic geographic information service platform in China and Sensor Web services to establish geo-sensor applications, and builds well-designed human-machine interfaces (HMIs) to support online and open interactions between human beings and physical sensors through cyberspace. The method was tested with experiments carried out in two geographically distributed scientific experimental fields, Baoxie Sensor Web Experimental Field in Wuhan city and Yemaomian Landslide Monitoring Station in Three Gorges, with three typical sensors chosen as representatives using the prototype system Geospatial Sensor Web Common Service Platform. The results show that the proposed method is an open, online, closed-loop means of control. [ABSTRACT FROM AUTHOR]

Poly(lactic co-glycolic acid) (PLGA) is widely used in diverse fields, especially in delivering biologically active proteins and drugs. For these applications, the knowledge of morphology and microstructure of PLGA micro-porous microspheres is of great importance since they strongly influence the drug delivering efficiency. In this study, micro-porous PLGA microspheres loaded by bovine serum albumin are investigated by using a full-field Zernike phase contrast transmission hard X-ray microscope. From three-dimensional reconstructions and segmentations, fundamental microstructural parameters such as size, shape, distribution and volume ratio among pores and proteins inside PLGA microspheres were obtained. These parameters are useful to understand the relationship between the internal microstructure and drug encapsulation, as well as the drug release efficiency of PLGA microspheres. The presented results demonstrate the capability of hard X-ray nano-tomography to characterize porous microspheres loaded with proteins and drugs, and also open a way to analyse, optimize and design new PLGA microspheres for specific applications. [ABSTRACT FROM AUTHOR]

Phase sensitive X-ray imaging methods can provide substantially increased contrast over conventional absorption-based imaging and therefore new and otherwise inaccessible information. The use of gratings as optical elements in hard X-ray phase imaging overcomes some of the problems that have impaired the wider use of phase contrast in X-ray radiography and tomography. So far, to separate the phase information from other contributions detected with a grating interferometer, a phase-stepping approach has been considered, which implies the acquisition of multiple radiographic projections. Here we present an innovative, highly sensitive X-ray tomographic phase-contrast imaging approach based on grating interferometry, which extracts the phase-contrast signal without the need of phase stepping. Compared to the existing phase-stepping approach, the main advantages of this new method dubbed "reverse projection" are not only the significantly reduced delivered dose, without the degradation of the image quality, but also the much higher efficiency. The new technique sets the prerequisites for future fast and low-dose phase-contrast imaging methods, fundamental for imaging biological specimens and in vivo studies. [ABSTRACT FROM AUTHOR]

Differential phase-contrast (DPC) X-ray imaging has been performed in the Talbot–Lau configuration, in which the X-ray source was a combination of an absorption grating and a laboratory X-ray generator. We report here quantitative analysis of partial coherence effects on the X-ray Talbot–Lau interferometer. Based on the visibility of the self-image, the well-known geometry condition is reproduced. It is shown that effects of partial coherence are determined by the opening ratio of the source grating, and that the effects are independent of the Talbot order and the type of the phase grating, a condition quite different from those in a Talbot interferometer. A possible explanation is discussed from the point of view of the effective spatial coherence length. Taking into account the available X-ray flux and experimental fluctuations, we present the optimum opening ratio. Furthermore, we mention that our results can also be successfully used to discuss the properties of a multiline X-ray source. [ABSTRACT FROM AUTHOR]

The influence of polychromaticity of the X-ray source on the performance of an X-ray Talbot interferometer applied for phase-contrast imaging is analyzed through numerical simulations based on the Fresnel diffraction theory. The presented simulation results show that the visibility of the self-image is fairly insensitive to the source polychromaticity and explain why the interferometer could be well combined with polychromatic X-ray sources in recent experiments. Furthermore, the self-image with a high visibility can be obtained under polychromatic illumination even at a high-order fractional Talbot distance. This fact implies that the acquired image quality for phase measurements can be improved, since the primary signal for phase measurement is proportional to the inter-grating distance. Finally, we mention that the results are also valid for Talbot–Lau interferometer and scanning double-grating configuration. [ABSTRACT FROM AUTHOR]

A simple framework that allows a new general diffraction enhanced imaging (DEI) equation to be derived is presented. This latter equation may explain all open problems associated with the equation introduced by Chapman and those not explained by the first DEI equation, such as the noise background due to the small-angle scattering reflected by the analyzer. Combing the DEI equation with computed tomography (CT) theory, we propose a new DEI–CT formula that explains qualitatively the contour contrast caused by extinction of the refraction. Two formulae with a new method to extract the refraction angle are also introduced. Within this new theoretical framework the three components of the gradient of the refractive index can be reconstructed. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Stenting versus medical treatment in patients with symptomatic vertebral artery stenosis: a randomised open-label phase 2 trial," by A. Compter and colleagues in the 2015 issue.

The problem of corporate governance structure is currently one of the crucial issues that restrict further reform of the natural monopoly industries in China. This article defines the objectives of corporate governance in natural monopoly industries, and cites the electric power industry as an example to analyze the characteristics of the governance structure of natural monopoly industries in developed countries such as Great Britain and the United States. It then provides analyses of the types of governance structure in China's natural monopoly industries and their existing problems. The authors propose the future direction and measures regarding reform of the corporate governance structure in the natural monopoly industries in China. [ABSTRACT FROM AUTHOR]

OBJECTIVE To compare the histological characteristics, cell proliferation, apoptosis and biological features in benign prostatic hyperplasia (BPH) in the peripheral (PZ) and transition zone (TZ) of the prostate. PATIENTS AND METHODS Tissue from BPH in TZ and PZ was obtained from 68 patients undergoing transrectal ultrasonography-guided biopsy and used for both morphometric analysis and immunohistochemical studies. The epithelial, stromal and luminal composition of the tissue was determined using a computer-assisted method for quantitative morphometric analysis. Apoptosis was detected as the apoptotic index (AI) using the TdT dUTP nick-end labelling assay. Cell proliferation was determined as the proliferation index (PI) using Ki-67 immunostaining. The expression of epidermal growth factor receptor (EGFR), transforming growth factor β1 (TGFβ1), androgen receptor (AR) and bcl-2 were assessed immunohistochemically. RESULTS There was no difference in the stroma/epithelium ratio between PZ and TZ hyperplastic nodules ( P > 0.05). The mean AI in epithelium was almost identical to the corresponding PI. In stroma, no apoptotic cells were detectable. There was a significantly higher PI and AI in the glandular epithelial cells in PZ hyperplastic than in TZ hyperplastic nodules, but no difference in PI of the stromal cells between PZ and TZ hyperplastic nodules. There was significantly higher expression of TGFβ1 and lower expression of EGFR and bcl-2 in PZ than TZ hyperplastic nodules ( P < 0.05). There was no difference in AR expression between PZ and TZ hyperplastic nodules ( P > 0.05). CONCLUSIONS These results indicate that some hyperplastic nodules in PZ might originate from the PZ, and the formation of these nodules might be modulated in a different way from that in the TZ. [ABSTRACT FROM AUTHOR]

Presents a study that demonstrated the genomic structure of elf-3 and the expression of ELF in the developing mouse brain using a peptide specific antibody against its distinctive amino-terminal end. Information on spectrins; Analysis of the genomic structure and expression in mid-embryonic central nervous system of elf-3; Identification of specific neuronal precursors and neurons that express ELF utilizing antibodies to domains unique to elf isoforms.

A label-free optical probe was developed for Ca2+ detection based on the aggregation-induced emission property of Au(i)-thiolate complexes. Upon incubation with Ca2+, the Au(i)-cysteine complexes rapidly aggregated through Cys-Ca2+ interaction, resulting in a luminescent emission of the complexes. The label-free probe was low cost, simple in design and fast in response [ABSTRACT FROM AUTHOR]