Impact of land use change on water resource allocation in the middle reaches of the Heihe River Basin in northwestern China

In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid re- gions of northwestern China. In order to sustain the expanding cropland, people increased groundwater exploitation in these regions. The purpose of this study was to quantitatively analyze the changes in land use and water resources, and their relationship in the middle reaches of the Heihe River Basin, a typical inland river basin in northwest China. The data of land use change were interpreted using aerial photographs （1965） and Landsat TM images （1986 and 2007）. The data of irrigation water volume in the irrigation districts were spatialized in the middle reaches of the Heihe River Basin. The spatial variation of the groundwater depth was interpolated using the geo- statistical method. The results showed that the cultivated cropland area along oasis fringe increased by 15.38% and 43.60% during the periods 1965-1986 and 1986-2007, respectively. Surface water amount for irrigation had almost doubled from 1956 to 2010. The decrease of grassland area mainly occurred at the alluvial fan in front of the Qilian Mountains, with 36.47% during 1965-1986 and 38.56% during 1986-2007, respectively. The groundwater depth in front of the mountain constantly increased from 1986 to 2007. We found that the overuse of surface water and overexploitation of groundwater had direct consequences on the natural environments. We suggests that the efficiency of surface water resources use among different irrigation distdcts needs to be improved, which will significantly ease the conflicts between increasing water demand for irrigation and a shortage of water resources in the middle reaches of the Heihe River Basin.

Remanufacturing Scheme Design for Used Parts Based on Incomplete Information Reconstruction

The different conditions of use of a component result in a variety of damage levels.Therefore,excluding differences in shape and size,used parts show a high degree of uncertainty regarding failure characteristics,quality conditions,and remaining life,which seriously affects the efficiency of a remanufacturing scheme design.Aiming to address this problem,a remanufacturing scheme design method based on the reconstruction of incomplete information of used parts is proposed.First,the remaining life of the reconstructed model is predicted by finite element analysis,and the demand for the next life cycle is determined.Second,the scanned 3D damage point cloud data are registered with the original point cloud data using the integral iterative method to construct a missing point cloud model to achieve the restoration of geometric information.Then,according to reverse engineering and laser cladding remanufacturing,the tool remanufacturing process path can be generated by the tool contact point path section line method.Finally,the proposed method is adopted for turbine blades to evaluate the effectiveness and feasibility of the proposed scheme.This study proposes a remanufacturing scheme design method based on the incomplete reconstruction of used part information to solve the uncertain and highly personalized problems in remanufacturing.

特力阿扎维林治疗新冠病毒肺炎的疗效和安全性——试验方案

根据2019年12月的报道,新冠病毒肺炎(coronavirus disease 2019, COVID-19)是由一种新型冠状病毒引起的肺炎。到目前为止,还没有发现能够治疗这种病毒的有效药物。本研究是一项在黑龙江省10个研究中心正在进行的多中心双盲随机对照试验(randomized controlled trial, RCT),其目的是研究与安慰剂相比,特力阿扎维林(triazavirin, TZV)治疗COVID-19患者的疗效和安全性。共计划招募240名COVID-19患者参加这项试验。咽拭子病毒核酸检测为阳性的受试者被随机(1∶1)分为两组:使用标准治疗加TZV或标准治疗加安慰剂,进行为期7 d的治疗和为期21 d的随访。主要结局是受试者临床改善的时间。次要结局包括临床改善率、退热时间、肺内炎症明显吸收的平均时间和人数比例、病毒核酸转阴率、病死率以及重症和危重症患者的转化率。整个试验过程将对不良事件,严重不良事件,肝功能、肾功能以及合并用药进行监测和记录。本试验的结果可为临床医生治疗COVID-19提供循证医学的证据和建议。

Effects of coagulation-bath conditions on polyphenylsulfone ultrafiltration membranes

Polyphenylsulfone(PPSU)ultrafiltration membrane with different structures was prepared by nonsolvent-induced phase separation.The effects of coagulation bath conditions(concentration and temperature)on membrane morphology,pure water flux,pore size,porosity,and contact angle were studied and discussed based on ternary-phase diagrams.Results indicated that water had stronger coagulant power than ethanol,and that the morphology of the membrane prepared from the polyphenylsulfone/1-methyl-2-pyrrolidinone/H_(2)O(PPSU/NMP/H_(2)O)system had finger-like structures.Conversely,sponge-like structures were observed for the PPSU/NMP/(NMP-H_(2)O)and PPSU/NMP/(70 NMP-EtOH-H_(2)O)systems.Ethanol also greatly influenced on membrane structures.According to the Scanning electronic microscopy(SEM)image,the composition(mass fraction)of casting solution is 16%PPSU-84%NMP and the coagulation bath consisting of 70%NMP-26%H_(2)O-4%C_(2)H_(5)OH.Meanwhile,the PPSU ultrafiltration membrane with spong-like was prepared under 8℃coagulation bath.The formation of sponge-like structure reduces the pure water flux of ppsu membrane from 488.39 L·m^(-2)·h^(-1)to 36.04 L·m^(-2)·h^(-1).It also reduces the gas permeability,porosity,and pore size of the membrane.The addition of ethanol and NMP into the coagulation bath increases the roughness of the PPSU ultrafiltration membrane and reduces the hydrophilicity of the membrane.

特力阿扎维林治疗新冠病毒肺炎的疗效与安全性——一项随机对照试验

目前,尚无有效疗法可治愈由严重急性呼吸综合征冠状病毒2(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)引起的新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)。为了评估抗病毒药物特力阿扎维林治疗COVID-19的有效性和安全性,本研究针对感染COVID-19的成年住院患者开展了一项随机双盲对照试验。本研究从10个分中心招募COVID-19患者,并将患者按1:1的比例随机分为两组。试验组的患者每天服用250 mg的特力阿扎维林药物3~4次,对照组患者则服用安慰剂,为期共7 d。主要结局指标为临床改善时间,临床改善时间的定义为随机分组28d内患者的体温、呼吸频率、血氧饱和度、咳嗽频率和肺CT(计算机断层扫描,computed tomography)所显示的肺部感染吸收情况全部恢复正常的时间。次要结局指标包括主要结局指标的5个组成指标,及肺部感染吸收的平均时间和吸收比例,以及用咽拭子采样法连续两次SARS-CoV-2核酸检测阴性的转阴率。与此同时,记录合并的治疗药物、不良事件和严重不良事件。由于需要进行住院治疗的新增感染病例的减少,本研究在招募52名患者后便停止招募。将52名受试者随机分为服用特力阿扎维林药物的试验组(n=26)和服用安慰剂的对照组(n=26)。结果显示,两组临床改善时间并无明显差异[中位数,7 d vs.12 d;风险比(RR)为2.0;95%置信区间(CI)为0.7~5.6;p=0.2]。服用特力阿扎维林的试验组中有10名患者发生临床改善,服用安慰剂的对照组中有6名患者出现临床改善(38.5%vs.23.1%,RR为2.1;95%CI为0.6~7.0;p=0.2)。除了肺部感染的吸收情况外(试验组50.0%,对照组26.1%),其余主要结局所观察指标均在28 d内恢复正常。此外,试验组的患者在呼吸系统、心脏、肾、肝或凝血功能等方面的合并治疗较对照组少。尽管特力阿扎维林药物对COVID-19患者的疗效尚未达到统计学上的显著性水平,但本研究结果表明,由于特力阿扎维林药物具有抗病毒作用,将其用于COVID-19的治疗也可能具有一定的疗效。对此,需要进一步的研究进行验证。

Laparoscopic Management of a Giant Congenital Splenic Cyst in a Child

Introduction Splenic cysts are rare in pediatric surgery.They can be classified as'true'cysts or pseudocysts on the basis of the presence or absence of an epithelial lining.Congenital cysts represent 10% of splenic cysts, most of which are epidermoid lesions.Splenectomy was initially the surgical treatment employed due to size,risk of operative compli-

RHMX:Bus Arrival Time Prediction via Mixed Model

With the widespread use of information technologies such as IoT and big data in the transportation business,traditional passenger transportation has begun to transition and upgrade into intelligent transportation,providing passengers with a better riding experience.Giving precise bus arrival times is a critical link in achieving urban intelligent transportation.As a result,a mixed model-based bus arrival time prediction model(RHMX)was suggested in this work,which could dynamically forecast bus arrival time based on the input data.First,two sub-models were created:bus station stopping time prediction and interstation running time prediction.The former predicted the stopping time of a running bus at each downstream station in an iterative manner,while the latter projected its running time on each downstream road segment(stations as the break points).Using the two models,a group of time series data on interstation running time and bus station stopping time may be predicted.Following that,the time series data from the two sub-models was fused using long short-term memory(LSTM)to generate an approximate bus arrival time.Finally,using Kalman filtering,the LSTM prediction results were dynamically updated in order to eliminate the influence of aberrant data on the anticipated value and obtain a more precise bus arrival time.The experimental findings showed that the suggested model's accuracy and stability were both improved by 35%and 17%,respectively,over AutoNavi and Baidu.

An introduction to the 3-dimensional virtual library sites-navigation system at Capital Normal University Library

Capital Normal University Library(CNU Library) initiated the first practical application of a 3D virtual library sites-navigation system(an electronic kiosk version)among Chinese academic and research libraries in 2010. It was primarily based on the technologies of 3DsMax and Virtools. This paper concentrates on the discussion of the methods in creating the 3D model and in realizing the interaction among the data usage of the system. As a result, several important service functions of the system have been developed successfully so far for convenient public access. They include the functions of virtual-book searching, path navigation online, real-time message exchanges, and multi-media sharing, etc.

Histopathological Features Predicting Long-term Clinical Outcomes in Patients with Vanishing Bile Duct Syndrome

Background and Aims:The clinicopathological features and long-term outcomes of patients with vanishing bile duct syndrome(VBDS)have yet to be elucidated.The study aims to investigate these features and identify factors associated with poor prognosis.Methods:This multicenter retrospective study recruited patients with liver biopsy-proven VBDS who were followed up at five hospitals in northern China from January 2003 to April 2022.Clinical and pathological data at time of biopsy were reviewed.Clinical outcomes including cirrhosis,decompensation events,liver transplantation(LT),and liver-related death were recorded.Cox regression analysis was used to identify the risk factors associated with poor outcomes.Results:A total of 183 patients were included.The median age was 47 years,with 77.6%being women.During a median follow-up of 4.8 years,88 patients developed compensated or decompensated cirrhosis,27 died,and 15 received LT.Multivariate Cox regression analysis showed that hepatocellular cholestasis(HR 2.953,95%CI:1.437–6.069),foam cells(HR 2.349,95%CI:1.092–5.053),and advanced fibrosis(HR 2.524,95%CI:1.313–4.851)were independent predictors of LT or liver-related deaths.A nomogram formulated with the above factors showed good consistency with a concordance index of 0.746(95%CI:0.706–0.785).Conclusions:Nearly half of VBDS patients studied progressed to end-stage liver disease and 23%of them had LT or liver-related death within two years of diagnosis.Hepatocellular cholestasis,foam cells and advanced fibrosis rather than the degree of bile duct loss or underlying etiologies were independently associated with poor prognosis in VBDS patients.

A bacterial symbiont in the gill of the marine scallop Argopecten irradians irradians metabolizes dimethylsulfoniopropionate

Microbial lysis of dimethylsulfoniopropionate(DMSP)is a key step in marine organic sulfur cycling and has been recently demonstrated to play an important role in mediating interactions between bacteria,algae,and zooplankton.To date,microbes that have been found to lyse DMSP are largely confined to free‐living and surface‐attached bacteria.In this study,we report for the first time that a symbiont(termed“Rhodobiaceae bacterium HWgs001”)in the gill of the marine scallop Argopecten irradians irradians can lyse and metabolize DMSP.Analysis of 16S rRNA gene sequences suggested that HWgs001 accounted for up to 93%of the gill microbiota.Microscopic observations suggested that HWgs001 lived within the gill tissue.Unlike symbionts of other bivalves,HWgs001 belongs to Alphaproteobacteria rather than Gammaproteobacteria,and no genes for carbon fixation were identified in its small genome.Moreover,HWgs001 was found to possess a dddP gene,responsible for the lysis of DMSP to acrylate.The enzymatic activity of dddP was confirmed using the heterologous expression,and in situ transcription of the gene in scallop gill tissues was demonstrated using reverse‐transcription PCR.Together,these results revealed a taxonomically and functionally unique symbiont,which represents the first‐documented DMSP‐metabolizing symbiont likely to play significant roles in coastal marine ecosystems.

山东胜利油田沾3油藏微生物组特征

以山东胜利油田沾3区注入水和采出液为研究对象,利用16S r RNA高通量测序技术,分析了油相样本、水相样本以及注入水样本的微生物群落结构.结果发现沾3油藏微生物多样性较高,注入水样本中细菌群落多样性最高,古菌群落多样性最低;而采出液油相样本的微生物群落多样性较采出液水相样本低.采出液微生物组的特征与注入水中微生物组的特征存在较大差异,具有明显的生境特异性.采出液油相样本与水相样本中主要的细菌类群包括γ-变形菌纲、ε-变形菌纲、α-变形菌纲、放线菌纲和梭状芽孢杆菌纲.在属水平上,采出液以假单胞菌占优势,而注入水中的优势菌属为硫单胞菌.采出液中古菌主要类群为甲烷微菌纲、甲烷杆菌纲、嗜盐菌纲、热原体纲、热变形菌纲和热球菌纲,尤其以鬃毛甲烷菌科和甲烷杆菌为主.对注入水和采出液水相中的油藏微生物与环境理化因子进行冗余分析(RDA)发现,注入水细菌和古菌群落均主要受SO42-浓度影响,采出液水相样本中的细菌群落主要受Ca2+浓度和pH等影响,而古菌群落则主要受Cl-, Mg2+和HCO3-浓度影响.该研究结果揭示了微生物在高温油藏环境中的空间分布特征及受控因素,为今后定向调控油藏微生物群落、进而提高微生物驱油的采油率奠定了基础.

油藏嗜热菌与膨润土的相互作用及其对储层防膨的意义

【目的】本文从胜利油田沾3区块的高温油藏的原油采出液中分离得到一株嗜热菌,通过其与膨润土的相互作用,尝试探讨油藏微生物作为油藏储层中水敏性矿物(如蒙皂石)改性剂的可能性。【意义】研究结果将在降低水敏矿物的膨胀性能,为解决水驱采油中遇到的水敏效应的瓶颈问题提供微生物的新途径。【结果】所得菌株为革兰氏阳性菌,呈杆状,具芽孢,兼性厌氧,鉴定为Geobacillus icigianus SL-1。菌株SL-1在厌氧条件下能够还原蒙皂石的结构铁。扫描电镜(SEM)结果显示,无菌对照体系中,蒙皂石呈不规则薄片状。而经微生物作用后,除薄片状蒙皂石外,另有板状次生矿物的生成。进一步能谱(EDS)分析表明,与薄片状蒙皂石相比,板状矿物含有较高的Al/Si比值,且含有明显的K^+信号。XRD结果显示,经过微生物作用后,固相物质中蒙皂石的百分比下降至47.7%,伊利石百分比上升至29.1%,而无菌对照组中蒙皂石的百分含量则为70.4%,伊利石的百分比则为19.8%。XRD物相分析和EDS结果均证实经过微生物作用后,部分蒙皂石转化成了伊利石。膨胀性能的分析进一步揭示菌株SL-1作用后,矿物膨胀性较初始矿物显著降低,缩膨率达到25.9%。以上结果为油藏储层防膨提供了重要的实验依据。

Adaptive immune responses to SARS-CoV-2 infection in severe versus mild individuals

The global Coronavirus disease 2019(COVID-19)pandemic caused by SARS-CoV-2 has affected more than eight million people.There is an urgent need to investigate how the adaptive immunity is established in COVID-19 patients.In this study,we proled adaptive immune cells of PBMCs from recovered COVID-19 patients with varying disease severity using single-cell RNA and TCR/BCR V(D)J sequencing.The sequencing data revealed SARS-CoV-2-specic shufing of adaptive immune repertories and COVID-19-induced remodeling of peripheral lymphocytes.Characterization of variations in the peripheral T and B cells from the COVID-19 patients revealed a positive correlation of humoral immune response and T-cell immune memory with disease severity.Sequencing and functional data revealed SARS-CoV-2-specic T-cell immune memory in the convalescent COVID-19 patients.Furthermore,we also identied novel antigens that are responsive in the convalescent patients.Altogether,our study reveals adaptive immune repertories underlying pathogenesis and recovery in severe versus mild COVID-19 patients,providing valuable information for potential vaccine and therapeutic development against SARS-CoV-2 infection.

Spectrofluorimetric analysis of captopril based on its obstruction effect of the nanomaterial surface energy transfer between acridine orange and gold nanoparticles

A simple and sensitive method for detection of captopril was established based on its obstructive effect on nanomaterial surface energy transfer(NSET). It was found that the acridine orange(AO) could be adsorbed onto the surface of citrated-gold nanoparticles(Au NPs) through electrostatic interaction. Incidentally, the fluorescence of AO was quenched owing to the dipole-dipole interaction of NSET between AO fluorophore and the Au NPs. However, captopril could obstruct the occurrence of NSET between AO and Au NPs effectively with the formation of Au-S covalent bonds between it and the Au NPs. Consequently, AO molecules were moved away from the surface of Au NPs leading to a decline of the energy transfer efficiency. Moreover, the fluorescence of AO could be gradually restored with the addition of captopril. Under the optimal conditions, the recovered fluorescence intensity correlated linearly with the concentration of captopril in the range of 400 nmol/L–2.0 μmol/L with a detection limit of 71 nmol/L. Besides, the proposed method was successfully applied for the detection of captopril in troches with the recovery of 93%–102% and the RSD lower than 2.24%. The results were in good agreement with those obtained from the HPLC method.

Of stars and galaxies–Co-authorship network and research

We examine the association between network centrality and research using the accounting research community setting.We establish co-authorship network using papers published in the five top accounting journals from 1980 to 2016.We find that the co-authorship network in accounting is a“small world”with some most connected authors playing a key role in connecting others.We use machine learning to label published papers with multiple topics and find patterns in topics over time.More importantly,we find that co-authorship network centrality is positively associated with future research productivity and topic innovation and that the impact of centrality on productivity is higher with more senior authors.Further,centrality of an author’s co-authors also has an incrementally positive impact.We conclude that network centrality positively influences research output.

Glutathione S-transferase genes in scallops and their diverse expression patterns after exposure to PST-producing dinoflagellates

The glutathione S-transferases(GSTs)are a superfamily of enzymes that function in cellular protection against toxic substances and oxidative stress.Bivalves could accumulate high concentration of paralytic shellfish toxins(PSTs)from harmful algae.To understand the possible involvement of GSTs in protecting bivalves during PST accumulation and metabolism,the GST genes were systemically analyzed in two cultured scallops,Azumapecten farreri and Mizuhopecten yessoensis,which were reported for PST deposition during harmful algae bloom.A total of 35 and 37 GSTs were identified in A.farreri(AfGSTs)and M.yessoensis(MyGSTs)genome,respectively,and the expansion of the sigma class from the cytosolic subfamily was observed.In both scallop species,sigma class GSTs showed higher expression than other members.The high GSTs expression was detected mainly during/after larvae stages and in the two most toxic organs,hepatopancreas and kidney.After ingesting PST-producing dinoflagellates,all the regulated AfGSTs in the hepatopancrcas were from the sigma class,but with opposite regulation pattern between Alexandrium catenella and A.minutum exposure.In scallop kidneys,where PSTs transformed into higher toxicity,more AfGSTs were regulated than in the hepatopancreas,and most of them were from the sigma class,with similar regulation pattern between A.catenella and A.minutum exposure.In M.yessoensis exposed to A.catenella,MyGST-σ2 was the only up-regulated MyGST in both hepatopancreas and kidney.Our results suggested the possible diverse function of scallop GSTs and the importance of sigma class in the defense against PSTs,which would contribute to the adaptive evolution of scallops in marine environments.

Tolerance and acceptance of hepatic venous pressure gradient measurement in cirrhosis(CHESS1904):An international multicenter study

Aim:To determine the tolerance and acceptance of hepatic venous pressure gradient(HVPG)measurements in patients with liver cirrhosis.Methods:This prospective international multicenter study included 271 patients with cirrhosis who were scheduled to undergo HVPG measurement between October 2019 and June 2020.Data related to the tolerance and acceptance of HVPG measurements were collected using descriptive questionnaires.Results:HVPG measurements were technically successful in all 271 patients,with 141(52.0%)undergoing HVPG measurement alone.The complication rate was 0.4%.Postoperative pain was significantly lower than preoperative expected pain(p<0.001)and intraoperative pain(p<0.001),and intraoperative pain was also significantly lower than preoperative expected pain(p=0.036).No,mild,moderate,severe,and intolerable discomfort scores were reported by 36.9%,44.6%,11.1%,6.3%,and 0.4%of these patients,respectively,during HVPG measurement and by 54.6%32.5%,11.4%,1.5%,and 0%,respectively,after HVPG measurement.Of these patients,39.5%had little understanding and 10%had no understanding of the value of HVPG measurement,with 35.1%and 4.1%regarding HVPG measurements as being of little or no help,respectively.Most patients reported that they would definitely(15.5%),probably(46.9%),or possibly(29.9%)choose to undergo additional HVPG measurements again,and 62.7%regarded the cost of the procedure as acceptable.Conclusion:HVPG measurement was safe and well‐tolerated in patients with cirrhosis,but patient education and communication are warranted to improve the acceptance of this procedure.

Absorption,fluorescence and resonance Rayleigh scattering spectra of hydrophobic hydrogen bonding of eosin Y/Triton X-100 nanoparticles and their analytical applications

In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding complexes.These complexes could further aggregate to form nanoparticles through the squeezing action of the water phase and Van Der Waals force,resulting in changes in the absorption spectrum and fluorescence quenching of EY as well as the significant enhancement of resonance Rayleigh scattering.This enables the sensitive determination of Triton X-100 using the fading spectrophotometry,fluorescence quenching method and RRS method.Among them,the RRS method shows the highest sensitivity with a detection limit of 20.6 ng mL-1 for Triton X-100.The optimum experimental conditions and factors that affect the absorption,fluorescence and RRS spectra were tested.The effects of coexisting substances were investigated and the results showed good selectivity.Based on these results,new spectrophotometric methods,fluorescence quenching method and RRS method for the determination of Triton X-100,were established.The hydrogen bonding association of eosin Y with Triton X-100 and the formation of nanoparticles as well as their effects on related spectral characteristics were discussed utilizing infrared,transmission electron microscope technique and quantum chemical method.

多度对寄生型网络嵌套结构的影响大于食草型网络

因为物种多度显著影响种间互作频率,分析食物网结构对物种多样性和稳定性影响时,应基于能够反映物种真实偏好的网络(即偏好网),而不是直接观察得到的网络(即观察网)。食草网络中(植物为低营养级)的植物资源多度大于寄生网络中(动物为低营养级)寄主资源多度,因此我们假设:寄生网络的结构比食草网络的结构更易受到多度效应的影响。为验证这一假设,我们从已发表的文献中收集了80个定量观察网络(包括34个植物-食草昆虫网络和46个寄生网络),应用有效多度模型去除物种多度对观察网络的影响,从而得出偏好网络。然后,我们应用weighted NODF和spectral radius两个嵌套系数表征网络嵌套性,分析了观察网和偏好网的物种链接数分布、相互作用均匀度、加权连通度和稳健性的差异。结果表明,在偏好网中,寄生网络的嵌套程度要低于食草网络,这可能是因为去除多度影响增加了种间作用频率的均匀度。偏好网的加权连通度和稳健性显著高于相应的观察网,表明偏好网比观察网具有更高的网络稳定性。未来的食物网研究不仅应关注互惠和拮抗网络的结构差异,还应该关注食草和寄生等不同类型拮抗食物网的结构差异。