AFSTGCN:Prediction for multivariate time series using an adaptive fused spatial-temporal graph convolutional network

The prediction for Multivariate Time Series(MTS)explores the interrelationships among variables at historical moments,extracts their relevant characteristics,and is widely used in finance,weather,complex industries and other fields.Furthermore,it is important to construct a digital twin system.However,existing methods do not take full advantage of the potential properties of variables,which results in poor predicted accuracy.In this paper,we propose the Adaptive Fused Spatial-Temporal Graph Convolutional Network(AFSTGCN).First,to address the problem of the unknown spatial-temporal structure,we construct the Adaptive Fused Spatial-Temporal Graph(AFSTG)layer.Specifically,we fuse the spatial-temporal graph based on the interrelationship of spatial graphs.Simultaneously,we construct the adaptive adjacency matrix of the spatial-temporal graph using node embedding methods.Subsequently,to overcome the insufficient extraction of disordered correlation features,we construct the Adaptive Fused Spatial-Temporal Graph Convolutional(AFSTGC)module.The module forces the reordering of disordered temporal,spatial and spatial-temporal dependencies into rule-like data.AFSTGCN dynamically and synchronously acquires potential temporal,spatial and spatial-temporal correlations,thereby fully extracting rich hierarchical feature information to enhance the predicted accuracy.Experiments on different types of MTS datasets demonstrate that the model achieves state-of-the-art single-step and multi-step performance compared with eight other deep learning models.

Improving millimeter-wave imaging quality using the vortex phase method

This paper investigates a new vortex wave imaging approach to improve the imaging quality of small metal targets of size less than 1.5 mm.Antennas with different spiral phase plates are designed to efficiently transmit vortex beams with orbital angular momentums(OAMs).By analyzing the OAM spectrum of the target,it was discovered that the predominant reflection contains a particular OAM mode that carries abundant azimuthal information.This can be explained by the OAM selectivity of the target and the guidance of the vortex transmitting beam.A simple reflection vortex imaging system was designed to capture the phase information.Measurement results show that the high image contrast reaches 14.9%,which is twice as high as that of the imaging without OAM.Both of simulations and experiments demonstrate that the vortex phase imaging approach proposed in this paper can effectively improve the imaging quality at 80 GHz.This approach is suitable for other millimeter wave imaging systems and is helpful to improve the resolution in anti-terrorism security checks.

Notch signaling controls chondrocyte hypertrophy via indirect regulation of Sox9

RBPjk-dependent Notch signaling regulates both the onset of chondrocyte hypertrophy and the progression to terminal chondrocyte maturation during endochondral ossification. It has been suggested that Notch signaling can regulate Sox9 transcription, although how this occurs at the molecular level in chondrocytes and whether this transcriptional regulation mediates Notch control of chondrocyte hypertrophy and cartilage development is unknown or controversial. Here we have provided conclusive genetic evidence linking RBPjk-dependent Notch signaling to the regulation of Sox9 expression and chondrocyte hypertrophy by examining tissuespecific Rbpjk mutant（Prx1Cre;Rbpjkf/f）, Rbpjk mutant/Sox9 haploinsufficient（Prx1Cre;Rbpjkf/f;Sox9f/1）,and control embryos for alterations in SOX9 expression and chondrocyte hypertrophy during cartilage development. These studies demonstrate that Notch signaling regulates the onset of chondrocyte maturation in a SOX9-dependent manner, while Notch-mediated regulation of terminal chondrocyte maturation likely functions independently of SOX9. Furthermore, our in vitro molecular analyses of the Sox9 promoter and Notch-mediated regulation of Sox9 gene expression in chondrogenic cells identified the ability of Notch to induce Sox9 expression directly in the acute setting, but suppresses Sox9 transcription with prolonged Notch signaling that requires protein synthesis of secondary effectors.

The theoretical study on intermittency and propagation of geodesic acoustic mode in L-mode discharge near tokamak edge

Through a systematically developed theory,we demonstrate that the motion of Instanton identified in Zhang et al(2017 Phys.Plasmas 24122304)is highly correlated to the intermittent excitation and propagation of geodesic acoustic mode(GAM)that is observed in tokamaks.While many numerical simulations have observed the phenomena,it is the first theory that reveals the physical mechanism behind GAM intermittent excitation and propagation.The preceding work is based on the micro-turbulence associated with toroidal ion temperature gradient mode,and slab-based phenomenological model of zonal flow.When full toroidal effect is introduced into the system,two branches of zonal flow emerge:the torus-modified low frequency zonal flow(TLFZF),and GAM,necessitating a unified exploration of GAM and TLFZF.Indeed,we observe that the transition from the Caviton to Instanton is triggered by a rapid zero-crossing of radial group velocity of drift wave and is found to be strongly correlated with the GAM onset.Many features peculiar to intermittent GAMs,observed in real machines,are thus identified in the numerical experiment.The results will be displayed in figures and in a movie;first for single central rational surface,and then with coupled multiple central rational surfaces.The periodic bursting first shown disappears as being replaced by irregular one,more similar to the intermittent characteristics observed in GAM experiments.

Evaluating the effects of topographical factors on the precipitation simulated by kilometer-scale versus quarter-degree dynamical downscaling models in eastern China

与传统的1/4度(≈25-30 km)动力降尺度模拟相比,公里尺度模拟的降水空间分布与观测结果更为接近.为了研究这一差异原因,本研究以华东地区为例,探究了地形因子在观测和模拟的降水中的作用.为了更好地体现地形因子对降水分布非均匀性的影响,以及不同地形因子作用的尺度差异,本研究采用多尺度地理加权回归模型,对五个主要地形因子与公里尺度和1/4度分辨率模拟的降水的关系进行了评估.基于观测数据的研究结果显示地形起伏度,地形高程和离海岸线距离对华东地区降水分布的非均匀性都有重要影响,其中地形起伏度在研究区大部分站点降水分布中起主导作用;公里尺度模拟结果基本反映了地形起伏度的主导作用;而1/4度模拟结果表现出降水对地形高程的过度依赖.本研究揭示了公里尺度地形分布对中国东部降水的非均匀分布的关键作用,研究结果可以为改进降水模拟提供新的思路.

The investigation of quasi coherent mode on EAST using Doppler reflectometry

An electrostatic Quasi coherent mode has been observed in density fluctuations and perpendicular velocity fluctuations with the frequency range of 3–80 k Hz on the Experimental Advanced Superconducting Tokamak using multi-channel Doppler reflectometry.It appears in the edge localized mode(ELM)-free period after L-H transition or in the inter-ELM period.The mode rotates almost together with the plasma with the poloidal wave number around 0.6cm-1 and its frequency chirps with plasma poloidal velocity.The mode can exist in a large radial coverage(ρ=0.75–0.98),and peaks near the top of pedestal,suggesting that it might be excited in the steep gradient pedestal region,and spread into the core area.

Investigation of phase modulation and propagation-route effect from unmatched large-scale structures for Doppler reflectometry measurement through 2D full-wave modeling

To interpret the common symmetric peaks caused by the large-scale structure in the complex S(f)spectrum from the heterodyne Doppler reflectometry(DR)measurement in EAST,a 2D circular-shaped O-mode full-wave model based on the finite-difference time-domain method is built.The scattering characteristics and the influences on the DR signal from various scales are investigated.When the structure is located around the cutoff layer,a moving radial or poloidal large-scale structure k_(θ)k_(θ),match(k_(θ),match is the theoretic wavenumber of Bragg scattering)could both generate an oscillation phase term called‘phase modulation’,and symmetrical peaks in the complex S(f)spectrum.It was found that the image-rejection ratio A_(−1)/A_(+1)(A_(±1)represents the amplitudes of±1 order modulation peaks)could be a feasible indicator for experiment comparison.In the case when the structure is near the cutoff layer with the same arrangement as the experiment for the edge DR channel,the curve of A_(−1)/A_(+1)versus kθcan be divided into three regions,weak asymmetrical range with k_(θ)/k_(0)0.15(k_(0)is the vacuum wavenumber),harmonics range with 0.15k_(θ)/k_(0)0.4,and Bragg scattering range of 0.4k_(θ)/k_(0)0.7.In the case when the structure is located away from the cutoff layer,the final complex S(f)spectrum is the simple superimposing of modulation and Bragg scattering,and the modulation peaks have an amplitude response nearly proportional to the local density fluctuation,called the‘propagationroute effect’.Under the H-mode experiment arrangement for the core DR,a critical fluctuation amplitude Amp(n_(e,Mod.@route))/Amp(n_(e,Tur.@MSA)∼1.3–4.1(Amp(n_(e,Mod.@route))refers to the pedestal large-scale structure amplitude and Amp(ne,Tur.@MSA)refers to turbulence amplitude at the main scattering area)is needed for the structure in the pedestal to be observed by the core DR measurement.The simulations are well consistent with the experimental results.These effects need to be carefully considered during the DR signal analyses as the injecting beam passes through the plasma region with large-scale structures.

Encapsulated Fe(IV)Molecular Complex for Photoacoustic Imaging

stable neutral Fe(IV)complex(Fe-HDCL),readily accessible on the g scale,was found to possess high water solubility and good stability(<5%degradation over 4 h upon photoirradiation).Fe-HDCL is green and absorbs light effectively in the visible region(500–800 nm)with aλmax at 650 nm(ɛ=7830 M^(−1)cm^(−1)).Fe-HDCL also exhibits photothermal(PT)behavior comparable to single-wall carbon nanotubes in the solid state.In aqueous solution,high PT conversion(η=72.6%)is achieved,and a strong hyperthermia-based inhibition of cell growth is observed upon subjecting Fe-HDCL to near-infrared 730 nm laser photoirradiation.Initial biological studies in vitro and in vivo confirmed that Fe-HDCL is biocompatible,clears readily,and allows the visual detection of blood vessels.Upon subjecting mice to intravenous injection at low doses(e.g.,50μmol·kg^(−1)),Fe-HDCL also permits the photoacoustic(PA)imaging of kidneys and the evaluation of renal fibrosis in mouse models.In addition,Fe-HDCL allows PA-based imaging of brain tissues,presumably reflecting its ability to pass through the blood-brain barrier.We thus propose that Fe-HDCL has a role to play as PT agent and as a photodiagnostic.

Effect of substrate preset temperature on crystal growth and microstructure formation in laser powder deposition of single-crystal superalloy

A successful repair of single-crystal components needs to avoid the stray grain formation and achieves continuous epitaxial growth of columnar dendrites in the repaired zone. In this study, the effect of substrate preset temperature on crystal growth and microstructure formation in laser powder deposition of single-crystal superalloy was studied through an improved mathematical model and corresponding experimental approaches. The results indicated that the variation of substrate preset temperature between-30℃ and ＋210℃ changes the molten pool morphology little, but obviously affects the columnar-to-equiaxed transition conditions. The preheating of substrate facilitates the stray grain formation and enlarges the primary columnar dendrite arm spacing, while the situation for precooling of substrate is opposite. Under the specific processing conditions, the critical condition for continuous epitaxial growth is that the substrate preset temperature Tsub≤ ＋90℃. When the substrate preset temperature Tsubis below ＋90℃, the height ratio of melting depth to total height of the molten pool is larger than that of stray grain, ensuring that stray grains can be completely remelted and the continuous columnar dendrites during the multi-layer laser powder deposition process on（001） surface of single-crystal substrate can be achieved.

An assessment of China-Japan-Korea Free Trade Agreement＇s economic and environmental impacts on China

Recently, China, Japan, and the Republic of Korea （Korea） are conducting a government-commis- sioned feasibility study on the Free Trade Agreement among the three countries （CJKFTA） to form a regional free trade zone in East Asia. Considering that freer trade can cause unexpected impact on domestic environment, there is a need to evaluate the environmental impact of such a trade policy. This move should be made to help negotiators understand and pay more attention to environ- mental issues during CJKFTA negotiations, and to help lobby with the government to carry out appropriate policy instruments for adaptation or mitigation. Following the Chain Reaction Assessment Method that integrates and links the elements of trade, production, and environment, the present research aims to quantitatively assess CJKFTA＇s possible impact on China＇s environment. This is done by estimating the variations of China＇s major conventional pollutants and greenhouse gases （GHGs） emission in two policy scenarios to represent CJKFTA＇s scale and composition effects on China＇s environment. Estimating the variations is based on a static Computable General Equilibrium model, working with Global Trade Analysis Project （GTAP） 7 database and China＇s energy- environment statistics. Based on these assessments, CJKFTA is predicted to lead to notable environmental impact, including increased emissions of agricultural total nitrogen, agricultural total phosphorus, chemical oxygen demand, and GHGs. On the other hand, decreased emissions of industrial SO2 and dust are also expected to happen. Suitable policies need to be made to combat negative effects and amplify positive ones, while aiming at a more sustainable regional freer trade system.

Exponential change of measure for general piecewise deterministic Markov processes

We consider a general piecewise deterministic Markov process(PDMP) X = {X_t}_(t≥0) with a measure-valued generator A, for which the conditional distribution function of the inter-occurrence time is not necessarily absolutely continuous. A general form of the exponential martingales that are associated with X is given by■By considering this exponential martingale to be a likelihood-ratio process, we define a new probability measure and show that the process X is still a general PDMP under the new probability measure. We additionally find the new measure-valued generator and its domain. To illustrate our results, we investigate the continuous-time compound binomial model.

Prevalent fecal contamination in drinking water resources and potential health risks in Swat, Pakistan

Fecal bacteria contaminate water resources and result in associated waterborne diseases.This study assessed drinking water quality and evaluated their potential health risks in Swat, Pakistan. Ground and surface drinking water were randomly collected from upstream to downstream in the River Swat watershed and analyzed for fecal contamination using fecal indicator bacteria（Escherichia coli） and physiochemical parameters（potential of hydrogen, turbidity, temperature, electrical conductivity, total dissolved solid, color, odor and taste）. The physiochemical parameters were within their safe limits except in a few locations, whereas, the fecal contaminations in drinking water resources exceeded the drinking water quality standards of Pakistan Environmental Protection Agency（Pak-EPA）,2008 and World Health Organization（WHO）, 2011. Multivariate and univariate analyses revealed that downstream urbanization trend, minimum distance between water sources and pit latrines/sewerage systems, raw sewage deep well injection and amplified urban,pastures and agricultural runoffs having human and animal excreta were the possible sources of contamination. The questionnaire survey revealed that majority of the local people using 10–20 years old drinking water supply schemes at the rate of 73% well supply,13% hand pump supply, 11% spring supply and 3% river/streams supply, which spreads high prevalence of water borne diseases including hepatitis, intestinal infections and diarrhea, dysentery, cholera, typhoid fever, jaundice and skin diseases in children followed by older and younger adults.

Optimization of heat source side technical scheme of combined heat and water system based on a coal-fired power plant

Recovering the waste heat(WH)of a power plant can conserve energy and reduce emissions.Scholars have proposed utilizing the WH of power plants in a combined heat and water(CHW)system,which is considered an economical,energy-saving,and environment-friendly way to integrate water and heat supply into long-distance transportation in urban areas of northern China.However,to date,a detailed design of the case on the heat source side of the CHW has not been developed.Therefore,in this study,the heat source side of a CHW system was divided into two cases:a single-generator set and a double-generator set,and both cases were optimized.The parameters of a multi-effect desalination(MED)process were examined;the optimal number of evaporation stages during the MED process was 12,and the optimal heat source temperature during the first stage was 700C.Then,by matching the extraction and exhaust steam flows,the WH of the exhaust steam in the heating season was finally utilized.Further,under each case optimal conditions,energy,exergy,and cost were analyzed.The results showed that the exergy efficiency in the heating season for each case was approximately 50%,whereas that in the non-heating season was approximately 3.5%.The economy and water quality of the single-generator case were better than those of the double-generator case.However,the absorption heat pump required in the single-generator case is difficult to realize because it operates under two working conditions.

Regional climate dynamical downscaling over the Tibetan Plateau——From quarter-degree to kilometer-scale

The Tibetan Plateau(TP)possesses the largest cryosphere in the world outside of the Arctic and Antarctic,and is the source of nine major rivers in Asia.The surface environment of the TP has undergone significant changes against the background of global warming.It is projected that the continuation of climate change in the future will result in most of the glaciers and frozen soil disappearing by the end of this century,and freshwater resources will be greatly reduced,on which 22%of the world’s population depends.These environmental changes are of great concern to global society given the influences of the TP on the climate at the global scale.However,great uncertainties exist in global climate simulations over the TP,which affects our ability to properly understand the associated water security crisis.Based on atmospheric dynamics and physical processes,dynamical downscaling can characterize surface conditions more accurately than global simulations,and better simulate and predict regional or local weather and climate situations.With advances in supercomputing,the grid spacing of dynamical downscaling simulations has been continuously increasing,marching the technique into the kilometer-scale era.In this paper,the origin and development of dynamical downscaling in the TP region from the quarter-degree to kilometer scale is firstly introduced,including an assessment of the advantages and disadvantages of dynamical downscaling at the kilometer scale over the TP.Then,the main land surface factors affecting the performance of dynamical downscaling over the TP are described,as well as a brief introduction to a land surface model with specific plateau characteristics.Specifically,it has emerged that perfecting the land surface model and improving the performance of land-atmosphere interaction are the most effective ways to advance the performance of dynamic downscaling in this region.Finally,the challenges and some recommended future research directions are discussed and proposed.

Understanding traditional Chinese medicine via statistical learning of expert-specific Electronic Medical Records

Backgrounds Traditional Chinese medicine(TCM)has been attracting lots of attentions from various disciplines recently.However,TCM is still mysterious because of its unique philosophy and theoretical thinking.Due to the lack of high quality data,understanding TCM thoroughly faces critical challenges.In this study,we introduce the Zhou Archive,a large-scale database of expert-specific Electronic Medical Records containing information about 73,000+ visits to one TCM doctor for over 35 years.Covering the full spectrum of diagnosis-treatment model behind TCM practice,the archive provides an opportunity to understand TCM from the data-driven perspective.Methods:Processing the text data in the archive via a series of data processing steps,we transformed the semistructured EMRs in the archive to a well-structured feature table.Based on the structured feature table obtained,a series of statistical analyses are implemented to learn principles of TCM clinical practice from the archive,including correlation analysis,enrichment analysis,embedding analysis and association pattern discovery.Results:A structured feature table of 14,000+features is generated at the end of the proposed data processing procedure,with a feature codebook,a term dictionary and a term-feature map as byproducts.Statistical analysis of the feature table reveals underlying principles about the diagnosis-treatment model of TCM,helping us better understand the TDM practice from a data-driven perspective.Conclusion:Expert-specific EMRs provide opportunities to understand TCM from the data-driven perspective.Taking advantage of recent progresses on NLP for Chinese,we can process a large number of TCM EMRs efficiently to gain insights via statistical analysis.

Two NIS1-like proteins from apple canker pathogen(Valsa mali)play distinct roles in plant recognition and pathogen virulence

Conserved effectors produced by phytopathogens play critical roles in plant-microbe interactions.NIS1-like proteins represent a newly identified family of effectors distributed in multiple fungal species.However,their biological functions in a majority of pathogenic fungi remain largely elusive and require further investigation.In this study,we characterized two NIS1-like proteins VmNIS1 and VmNIS2 from Valsa mali,the causal agent of apple Valsa canker.Both of these two proteins were predicted to be secreted.Using agroinfiltration,we found that VmNIS1 induced intense cell death,whereas VmNIS2 suppressed INF1 elicitin-triggered cell death in Nicotiana benthamiana.Treatment of N.benthamiana with VmNIS1 recombinant protein produced by Escherichia coli activated a series of immune responses and enhanced plant disease resistance against Phytophthora capsici.In contrast,VmNIS2 suppressed plant immune responses and promoted P.capsici infection when transiently expressed in N.benthamiana.Both VmNIS1 and VmNIS2 were shown to be highly induced at late stage of V.mali infection.By individually knocking out of these two genes in V.mali,however,only VmNIS2 was shown to be required for pathogen virulence as well as tolerance to oxidative stress.Notably,we further showed that C-terminal extension of VmNIS1 was essential for plant recognition and VmNIS2 may escape plant detection via sequence truncation.Our data collectively indicate that VmNIS1 and VmNIS2 play distinct roles in plant recognition and pathogen virulence,which provided new insights into the function of NIS1-like proteins in plant-microbe interactions.

High carrier mobility and strong fluorescence emission: Toward highly sensitive single-crystal organic phototransistors

Organic single crystals(OSCs)offer a unique combination of both individual and collective properties of the employed molecules,but it remains highly challenging to achieve OSCs with both high mobilities and strong fluorescence emissions for their potential applications in multifunctional optoelectronics.Herein,we demonstrate the design and synthesis of two novel triphenylamine-functionalized thienoacenes-based organic semiconductors,4,8-distriphenylamineethynylbenzo[1,2-b:4,5-b′]dithiophene(4,8-DTEBDT)and 2,6-distriphenylamineethynylbenzo[1,2-b:4,5-b′]dithiophene(2,6-DTEBDT),with high-mobility and strong fluorescence emission.The two compounds show the maximum mobilities up to 0.25 and 0.06 cm^(2) V^(-1) s^(-1),the photoluminescence quantum yields(PLQYs)of 51% and 45%,and the small binding energies down to 55.13 and 58.79 meV.The excellent electrical and optical properties ensured the application of 4,8-DTEBDT and 2,6-DTEBDT single crystals in ultrasensitive UV phototransistors,achieving high photoresponsivity of 9.60×105 and 6.43×10^(4) AW^(-1),and detectivity exceeding 5.68×10^(17) and 2.99×10^(16) Jones.