Large area^(3)He tube array detector with modular design for multi‑physics instrument at CSNS

The multi-physics instrument(MPI)is the first user cooperative instrument at the China Spallation Neutron Source(CSNS).It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering technique.This imposes the requirements for the detector,including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum transfers.To satisfy these demands,a large-area array of 3He-filled linear position-sensitive detectors(LPSDs)was constructed,each with a diameter of 1 inch and pressure of 20 atm.It uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs,covering a range of scattering angles from 3°to 170°with a total detector area of approximately 7 m2.The detector works in air,which is separated from the vacuum environment to facilitate installation and maintenance.The characteristics of the MPI detector were investigated through Monte Carlo(MC)simulations using Geant4 and experimental measurements.The results suggest that the detectors are highly efficient in the wavelength range of the MPI,and an efficiency over 25%is achievable for above 0.1 A neutrons.A minimal position resolution of 6.4 mm full width at half maximum(FWHM)along the tube length was achieved at a working voltage of 2200 V,and a deviation below 2 mm between the real and measured positions was attained in the beam experiment.The detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz,which satisfied the requirements of experiments with a high event rate.Observations of its operation over the past year have shown that the detector works steadily in sample experiments,which allows the MPI to serve the user program successfully.

Application progress of nursing intervention in cardiac surgery

As a stressor,cardiac surgery affects the physiology and psychology of patients,as well as their postoperative recovery.Patients tend to worry about cognitive deficiency,pain,discomfort,the risk of death,sleep,complications,and other factors,resulting in stress and anxiety.Moreover,serious adverse events,such as circulatory and respiratory dysfunction and infection,tend to occur after cardiac surgery and increase the economic burden on patients.Therefore,appropriate nursing interventions should be selected to strengthen patients’cognitive levels,compliance,and postoperative practices to accelerate their recovery,reduce complications,and shorten hospital stays so as to contribute to patients’lives and health.

Laboratory culture of the freshwater benthic gastropod Bellamya aeruginosa (Reeve) and its utility as a test species for sediment toxicity

This study aimed to develop original laboratory culture and sediment toxicity testing protocols for the freshwater gastropod Bellamya aeruginosa （Reeve）, a new potential species for sediment toxicity testing. B. aeruginosa was successfully cultured with an effective culture system under proposed laboratory conditions. Optimal ad libitum feeding levels for larvae, juveniles, and adults were 2.0, 6.0, and 16.0 mg fish food/（snall.day）, respectively. Mean survival rates of juveniles were higher than 90%, The snails could be sexed at 9 weeks of age, and their generation time is approximately 4 months. Reproduction continued all year around; the mean fecundity was 0.55 newborn/（female.day）. The utility of this species for bioassays was evaluated in both 10-day and 28-day case studies with artificial sediments. The 10-day LC50 of Cu for larvae was 480 μg/g dry weight （dw）, and the lowest observed effects concentration of Cu for survival and growth of larvae was 195 μg/g dw. Survival and growth are reliable indicators of acute toxicity. Larvae accumulated more Cu than adults. B. aeruginosa exhibited a higher sensitivity to Cu exposure than standard test species （Hyalella azteca and Chironomus tentans）. The 28-day test of sediment toxicity with adults showed that fecundity was a robust endpoint indicator of reproductive toxicity, and the biochemical endpoints of superoxide dismutase, catalase, and glutathione could be used as sensitive biomarkers for Cu-induced oxidative damage. B. aeruginosa can be therefore recommended as a candidate for the standardization of the freshwater sediment toxicity test protocol.

Basic transcription factor 3 is involved in gastric cancer development and progression

AIM: To further analyse cancer involvement of basic transcription factor 3 (BTF3) after detection of its upregulation in gastric tumor samples. METHODS: BTF3 transcription rates in human gastric tumor tissue samples (n = 20) and adjacent normal tissue (n = 18) specimens as well as in the gastric cancer cell lines AGS, SGC-7901, MKN-28, MKN-45 and MGC803 were analyzed via quantitative real-time polymerase chain reaction. The effect of stable BTF3 silencing via infection with a small interfering RNA (siRNA)-BTF3 expressing lentivirus on SGC-7901 cells was measured via Western blotting analysis, proliferation assays, cell cycle and apoptosis profiling by flow cytometry as well as colony forming assays with a Cellomic Assay System. RESULTS: A significant higher expression of BTF3 mRNA was detected in tumors compared to normal gastric tissues (P < 0.01), especially in section tissues from female patients compared to male patients, and all tested gastric cancer cell lines expressed high levels of BTF3. From days 1 to 5, the relative proliferation rates of stable BTF3-siRNA transfected SGC7901 cells were 82%, 70%, 57%, 49% and 44% compared to the control, while the percentage of cells arrested in the G 1 phase was significantly decreased (P = 0.000) and the percentages of cells in the S (P = 0.031) and G 2 /M (P = 0.027) phases were significantly increased. In addition, the colony forming tendency was significantly decreased (P = 0.014) and the apoptosis rate increased from 5.73% to 8.59% (P = 0.014) after BTF3 was silenced in SGC7901 cells. CONCLUSION: BTF3 expression is associated with enhanced cell proliferation, reduced cell cycle regulation and apoptosis and its silencing decreased colony forming and proliferation of gastric cancer cells.

Notch1 Drives the Formation and Proliferation of Intrahepatic Cholangiocarcinoma

The molecular mechanisms underlying the development of intrahepatic cholangiocarcinoma(ICC)are not clear yet.In this study,we investigated the involvement of Notch1 in the development of ICC.The cDNA microarray analysis showed that Notch1 expression was higher in ICC tissues than in normal biliary epithelial cells.Stable transfection of Notchl receptor intracellular domain(NICD1)by hydrodynamic tail vein injection induced ICC formation in mice.Western blotting confirmed that Notchl signaling was activated in human ICC cell lines and mouse ICC tissues.Silencing Notchl with specific short interfering RNA(siRNA)inhibited the proliferation of ICC cells.Flow cytometry and Western blotting indicated that apoptosis was induced in Notchl-silenced ICC cells compared with controls.Additionally,Notchl silencing was associated with the inhibition of hairy and enhancer of split-1(Hes1)and activation of the phosphatase and tensin homolog(PTEN)/p53 pathway.Taken together,these data suggest that Notchl drives ICC formation and proliferation;downregulation of Notchl induces apoptosis in ICC cells;Notchl signaling may serve as a novel therapeutic target for the treatment of ICC.

New role and molecular mechanism of Gadd45a in hepatic fibrosis

AIM: To investigate the role of Gadd45a in hepatic fibrosis and the transforming growth factor (TGF)-beta/ Smad signaling pathway. METHODS: Wild-type male BALB/c mice were treated with CCl4 to induce a model of chronic liver injury. Hepatic stellate cells (HSCs) were isolated from the liver of BALB/c mice and were treated with small interfering RNAs (siRNAs) targeting Gadd45a or the pcDNA3.1-Gadd45a recombinant plasmid. Cellular alpha-smooth muscle actin (alpha-SMA), beta-actin, type I collagen, phospho-Smad2, phospho-Smad3, Smad2, Smad3, and Smad4 were detected by Western blots. The mRNA levels of alpha-SMA, beta-actin, and type I collagen were determined by quantitative real-time (qRT)-PCR analyses. Reactive oxygen species production was monitored by flow cytometry using 2,7-dichlorodihydrofluorescein diacetate. Gadd45a, Gadd45b, anti-Gadd45g, type I collagen, and SMA local expression in liver tissue were measured by histologic and immunohistochemical analyses. RESULTS: Significant downregulation of Gadd45a, but not Gadd45b or Gadd45g, accompanied by activation of the TGF-beta/Smad signaling pathways was detected in fibrotic liver tissues of mice and isolated HSCs with chronic liver injury induced by CCl4 treatment. Overexpression of Gadd45a reduced the expression of extracellular matrix proteins and alpha-SMA in HSCs, whereas transient knockdown of Gadd45a with siRNA reversed this process. Gadd45a inhibited the activity of a plasminogen activator inhibitor-1 promoter construct and (CAGA)(9) MLP-Luc, an artificial Smad3/4-specific reporter, as well as reduced the phosphorylation and nuclear translocation of Smad3. Gadd45a showed protective effects by scavenging reactive oxygen species and upregulating antioxidant enzymes. CONCLUSION: Gadd45a may counteract hepatic fibrosis by regulating the activation of HSCs via the inhibition of TGF-beta/Smad signaling.

Blade-coated organic solar cells from non-halogenated solvent offer 17%efficiency

Organic solar cell(OSC)has attracted great interests due to its potential applications[1-9].To date,18%power conversion efficiency(PCE)has been achieved in single-junction OSC[10−13],indicating the feasibility of commercialization.This photovoltaic technology currently faces the performance gap between laboratory cells and large-area modules.

Compact lithium-glass neutron beam monitor for SANS at CSNS

A small-angle scattering neutron spectrometer for material research is under construction at the China Spallation Neutron Source. An intervening neutron beam monitor behind the sample is needed to measure the beam intensity in order to reduce the measurement uncertainty caused by beam fluctuation. Considering the mobility requirement and limited space, we proposed a compact monitor using a type of lithium-glass scintillator provided by China Building Materials Academy. Its performance was studied experimentally using ^(252)Cf and ^(60)Co sources.The neutron light yield of the selected scintillator was measured to be 5:3 × 10~3 photons/neutron. The feasibility of n-gamma discrimination using the charge comparison method was verified. By using the Geant4 toolkit, themonitor was modeled with precise physical processes including neutron tracking, scintillation, and optical photon transmission. The gamma sensitivity and detection efficiency were investigated in the simulation. It was concluded that a 0.5-mm-thick lithium-glass scintillator with natural lithium is an appropriate choice to satisfy both the neutron detection efficiency and gamma elimination requirements.

Slenderness Ratio Effect on the Eccentric Compression Performance of Chamfered Laminated Bamboo Lumber Columns

Eccentric compression tests on 15 chamfered laminated bamboo lumber(LBL)columns with a height ranging from 600 to 3000 mm were conducted in order to study the eccentric mechanical performance.The failure of all specimens was caused by the crack of bamboo fiber in the tensile region.When the ultimate strength was reached,except specimens with a height of 600 mm,all other specimens could bear large deformation,showing good ductility.The lateral displacements of the specimens under eccentric compression were approximately para-bolic in the direction of column height.The ultimate bending moment of LBL columns with different slenderness ratios under compression with the same initial eccentricity was a fixed value.The relationship between ultimate capacity,axial displacement,lateral displacement,and slenderness ratio was analyzed based on test results.It was found that the plane section assumption could be used to express the stress and strain distribution of chamfered LBL columns under eccentric compression.A method for calculating the ultimate bearing capacity was proposed using a constitutive model based on the Ramberg-Osgood relation and the empirical formula for calculating the ultimate capacity was given on the basis of the former research as well as the test results in this paper.

WiBPA:An Efficient Data Integrity Auditing Scheme Without Bilinear Pairings

The security of cloud data has always been a concern.Cloud server provider may maliciously tamper or delete user’s data for their own benefit,so data integrity audit is of great significance to verify whether data is modified or not.Based on the general three-party audit architecture,a dynamic auditing scheme without bilinear pairings is proposed in this paper.It utilizes exponential operation instead of bilinear mapping to verify the validity of evidence.By establishing the mapping relation between logic index and tag index of data block with index transformation table,our scheme can easily support dynamic data operation.By hiding random numbers in the integrity evidence,our scheme can protect users’privacy information.Detailed security analysis shows that our scheme is secure against attacks such as forgery,replaying and substitution.Further experiments demonstrate that our scheme has lower computational overhead.

Reversible potassium storage in ultrafine CF_(x): A superior cathode material for potassium batteries and its mechanism

Current studies of cathodes for potassium batteries(PBs) mainly focus on the intercalation-type materials.The conversion-type materials that possess much higher theoretical capacities are rarely discussed in previous literatures.In this work,carbon fluoride(CF_x) is reported as a high capacity conversion-type cathode for PBs for the first time.The material delivers a remarkable discharge capacity of>250 mAh g^(-1) with mid-voltage of 2.6 V at 20 mA g^(-1).Moreover,a highly reversible capacity of around 95 mAh g^(-1) is achieved at 125 mA g^(-1) and maintained for 900 cycles,demonstrating its excellent cycling stability.The mechanism of this highly reversible conversion reaction is further investigated by nuclear magnetic resonance spectra,X-ray diffraction,and transmission electron microscopy studies.According to the analyses,the C-F bond in the cycled material is different from that in the pristine state,which presents relatively higher reversibility.This finding offers important insights for further improving the performance of the CF_x.This work not only demonstrates the CF_x as a high performance cathode for PBs,but also paves a new avenue of exploring conversion-type cathodes for high energy density PBs.

Time-Domain Analysis of the Relative Motions Between Side-by-Side FLNG and LNGC Under Oblique Waves

Strong hydrodynamic interactions during the side-by-side offloading operation between floating liquefied natural gas(FLNG) and liquefied natural gas carrier(LNGC) can induce high risks of collision. The weather vane effect of a single-point mooring system normally results in the satisfactory hydrodynamic performance of the side-by-side configuration in head seas. Nevertheless, the changes in wave directions in real sea conditions can significantly influence the relative motions. This article studies the relative motions of the side-by-side system by using the theoretical analysis method and the numerical calculation method. Based on the three-dimensional potential theory modified by artificial damping-lid method, the frequency-domain hydrodynamic coefficients can be improved to calculate the retardation functions for the multi-body problem. An in-house code is then developed to perform the time-domain simulation of two vessels, through which the relative motions are subsequently obtained. A range of oblique waves are chosen for the extensive calculation of relative motions between the two vessels, which are further analyzed in terms of the phase shift of motion responses induced by specific resonant wave patterns. Investigation results show that wave directions have a significant influence on the relative sway, roll, and yaw motions. Under the circumstance that the absolute phase shift between the roll motions of two vessels approaches 180°, stronger relative motions are induced when LNGC is on the weather side.Moreover, the gap water resonances at high frequencies tend to cause the dangerous opposed oscillation of two vessels in the sway and yaw modes, whereas FLNG reduces the gap water resonances and relative motions when located on the weather side.

Experimental Study and Numerical Simulation of Polymer Flooding

The numerical simulation of polymer flooding is a complex task as this process involves complex physical and chemical reactions,and multiple sets of characteristic parameters are required to properly set the simulation.At present,such characteristic parameters are mainly obtained by empirical methods,which typically result in relatively large errors.By analyzing experimentally polymer adsorption,permeability decline,inaccessible pore volume,viscosity-concentration relationship,and rheology,in this study,a conversion equation is provided to convert the experimental data into the parameters needed for the numerical simulation.Some examples are provided to demonstrate the reliability of the proposed approach.

Effect of Cardioplegia for Myocardial Protection in Pediatric Cardiac Surgery:A Network Meta-Analysis

Cardioplegia has been widely used to reduce myocardial injury during pediatric cardiac surgery;however,which cardioplegia solution has the best protective effect has not been established.Thus,we compared the myocardial protective effects of different cardioplegia solutions used in pediatric cardiac surgery.Seven databases were searched to identify the relevant randomized controlled trials.A network meta-analysis with a Bayesian framework was conducted.The outcomes included the following biochemical and clinical outcomes:serum concentrations of the creatine kinase-myocardial band at 6 h postoperatively;cardiac troponin I(cTnI)at 4,12,and 24 h postoperatively;spontaneous beating after declamping;postoperative arrhythmias;inotropic support percentage and duration;mechanical ventilation hours;intensive care unit stay in days;hospital stay in days;and mortality.The group treated with cold crystalloid cardioplegia(cCCP)was chosen as the control group.The 22 studies involved 1529 patients.Six types of cardioplegia solutions were described in these studies,including cold blood cardioplegia,cCCP,del Nido,histidine-tryptophan-ketoglutarate(HTK),terminal warm blood cardioplegia,and warm blood cardioplegia(wBCP).The serum concentrations of the 24-h cTnI with wBCP(MD=−2.52,95%CI:−4.74 to−0.27)was significantly lower than cCCP.The serum concentrations of the 24-h cTnI with HTK(MD=4.91,95%CI:2.84–7.24)was significantly higher than cCCP.There was no significant difference in other biochemical and clinical outcomes when compared to cCCP.In conclusion,wBCP may have a superior myocardial protective effect with lower 24-h cTnI levels postoperatively and similar clinical outcomes after pediatric cardiac surgery.

dCACH: Content Aware Clustered and Hierarchical Distributed Deduplication

In deduplication, index-lookup disk bottleneck is a major obstacle which limits the throughput of backup processes. One way to minimize the effect of this issue and boost speed is to use very high course-grained chunks for deduplication at a cost of low storage saving and limited scalability. Another way is to distribute the deduplication process among multiple nodes but this approach introduces storage node island effect and also incurs high communication cost. In this paper, we explore dCACH, a content-aware clustered and hierarchical deduplication system, which implements a hybrid of inline course grained and offline fine-grained distributed deduplication where routing decisions are made for a set of files instead of single files. It utilizes bloom filters for detecting similarity between a data stream and previous data streams and performs stateful routing which solves the storage node island problem. Moreover, it exploits the negligibly small amount of content shared among chunks from different file types to create groups of files and deduplicate each group in their own fingerprint index space. It implements hierarchical deduplication to reduce the size of fingerprint indexes at the global level, where only files and big sized segments are deduplicated. Locality is created and exploited first using the big sized segments deduplicated at the global level and second by routing a set of consecutive files together to one storage node. Furthermore, the use of bloom filter for similarity detection between streams has low communication and computation cost while it enables to achieve duplicate elimination performance comparable to single node deduplication. dCACH is evaluated using a prototype deployed on a server environment distributed over four separate machines. It is shown to have 10× the speed of Extreme_Binn with a minimal communication overhead, while its duplicate elimination effectiveness is on a par with a single node deduplication system.

面子倾向促进还是阻碍员工越轨创新行为?基于独特性需求的理论视角

面子倾向是中国文化情境中一种根深蒂固且影响深远的价值取向。虽然以往研究已经发现员工的价值取向可以影响其越轨创新行为,但尚无研究关注面子倾向这种中国文化情境下独特的本土化价值取向如何影响员工的越轨创新行为。为了解答面子倾向促进还是阻碍员工越轨创新行为的研究问题,本研究基于独特性需求理论,构建了面子倾向影响员工越轨创新行为的被调节的中介模型。本研究对429位企业员工进行了问卷调查,回归分析结果表明:获得型面子倾向通过提高员工的独特性需求进而促进员工越轨创新行为,而保护型面子倾向通过降低员工的独特性需求进而阻碍员工越轨创新行为;心理安全感可以增强独特性需求对越轨创新行为的正向影响,并且增强获得型面子倾向对越轨创新行为的正向间接影响,但对保护型面子倾向对越轨创新行为的间接影响没有显著的调节作用。本研究揭示了面子倾向影响越轨创新行为的中介和调节机制,为回答在中国文化情境下哪种面子倾向的员工更容易进行越轨创新行为的问题提供了理论依据。

Transmission Line Insulator Defect Detection Based on Swin Transformer and Context

Insulators are important components of power transmission lines.Once a failure occurs,it may cause a large-scale blackout and other hidden dangers.Due to the large image size and complex background,detecting small defect objects is a challenge.We make improvements based on the two-stage network Faster R-convolutional neural networks(CNN).First,we use a hierarchical Swin Transformer with shifted windows as the feature extraction network,instead of ResNet,to extract more discriminative features,and then design the deformable receptive field block to encode global and local context information,which is utilized to capture key clues for detecting objects in complex backgrounds.Finally,the filling data augmentation method is proposed for the problem of insufficient defects and more images of insulator defects under different backgrounds are added to the training set to improve the robustness of the model.As a result,the recall increases from 89.5%to 92.1%,and the average precision increases from 81.0%to 87.1%.To further prove the superiority of the proposed algorithm,we also tested the model on the public data set Pascal visual object classes(VOC),which also yields outstanding results.

具有NIR-Ⅱ吸收的碳包覆磁铁矿纳米团簇用于成像引导的光热-化学动力学协同治疗

化学动力学疗法(CDT)是基于磁铁矿纳米酶治疗癌症的新兴治疗方式.但是,它的低催化能力和单模治疗限制了其治疗功效.本工作中,我们开发了一种在第二近红外(NIR-Ⅱ)窗口中具有高吸光度的碳涂覆的磁铁矿纳米团簇(CCMNCs),用于NIR-Ⅱ光热增强的化学动力抗癌疗法.这种尺寸约58 nm的CCMNCs通过使用二茂铁作为单一前体的一步溶剂热法合成.CCMNCs不仅用作肿瘤靶向磁共振成像的造影剂,而且还吸收并将NIR-Ⅱ辐射转化为局部热量,用于高温杀死癌细胞.CCMNCs在酸溶液中产生的亚铁离子和铁离子催化Fenton反应生成CDT的羟基自由基(·OH),并减少作为自由基清除剂的细胞内谷胱甘肽.本文报道的CCMNCs通过组合的化学动力学光热处理的协同效应显示出优异的治疗功效.

A disk failure prediction model for multiple issues

Disk failure prediction methods have been useful in handing a single issue,e.g.,heterogeneous disks,model aging,and minority samples.However,because these issues often exist simultaneously,prediction models that can handle only one will result in prediction bias in reality.Existing disk failure prediction methods simply fuse various models,lacking discussion of training data preparation and learning patterns when facing multiple issues,although the solutions to different issues often conflict with each other.As a result,we first explore the training data preparation for multiple issues via a data partitioning pattern,i.e.,our proposed multi-property data partitioning(MDP).Then,we consider learning with the partitioned data for multiple issues as learning multiple tasks,and introduce the model-agnostic meta-learning(MAML)framework to achieve the learning.Based on these improvements,we propose a novel disk failure prediction model named MDP-MAML.MDP addresses the challenges of uneven partitioning and difficulty in partitioning by time,and MAML addresses the challenge of learning with multiple domains and minor samples for multiple issues.In addition,MDP-MAML can assimilate emerging issues for learning and prediction.On the datasets reported by two real-world data centers,compared to state-of-the-art methods,MDP-MAML can improve the area under the curve(AUC)and false detection rate(FDR)from 0.85 to0.89 and from 0.85 to 0.91,respectively,while reducing false alarm rate(FAR)from 4.88%to 2.85%.

Molecular-scale integrated multi-functions for organic lightemitting transistors

Organic light-mitting transistors(OLETs)integrate the functions of light-emitting diodes and field-effect transistors into a unique device,opening a new door for optoelectronics.However,there is still a challenge due to the absence of high quality organic semiconductors for OLETs.Herein,we reported a novel molecule 2,6-di(anthracen-2-yl)naphthalene(2,6-DAN),which exhibited mobility of up to 19 cm2:V'-s'and an absolute fluorescence quantum yield of 37.09%,which are good values for organic semiconductors.Moreover,OLETs based on 2,6-DAN single crystals showed bright yellowish-green emission and well-balanced ambipolar charge transport.The excellent ratio of hole to electron mobilty can reach up to 0.86,which is superior to most single component OL ETs in typical device configurations reported so far.