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Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming xia Yong-Jun Ye shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the environment.Among these measurement methods,the closed-loop method is frequently used.However,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation chamber.The CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and visually.In this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the chamber.The consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was verified.The effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were investigated.Based on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion effect.The CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

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Emergent symmetry in quantum phase transition:From deconfined quantum critical point to gapless quantum spin liquid

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Science Bulletin 2024年第2期69卷 190-196页

作者： Wen-Yuan Liu Shou-shu Gong Wei-Qiang Chen zheng-Cheng Gu Department of Physics The Chinese University of Hong KongHong KongChina Division of Chemistry and Chemical Engineering California Institute of TechnologyPasadena CA 91125USA School of Physical Sciences Great Bay UniversityDongguan 523000China Great Bay Institute for Advanced Study Dongguan 523000China Department of Physics and Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase transitions.Here we unveil the behaviour of emergent symmetry involving two extraordinarily representative phenomena,i.e.,the deconfined quantum critical point(DQCP)and the quantum spin liquid(QSL)state.Via large-scale tensor network simulations,we study a spatially anisotropic spin-1/2 square-lattice frustrated antiferromagnetic(AFM)model,namely the J1x-J1y-J2 model,which contains anisotropic nearestneighbor couplings J1x,J1y and the next nearest neighbor coupling J2.For small J1y/J1x,by tuning J2,a direct continuous transition between the AFM and valence bond solid phase is observed.With growing J1y/J1x,a gapless QSL phase gradually emerges between the AFM and VBS phases.We observe an emergent O(4)symmetry along the AFM–VBS transition line,which is consistent with the prediction of DQCP theory.Most surprisingly,we find that such an emergent O(4)symmetry holds for the whole QSL–VBS transition line as well.These findings reveal the intrinsic relationship between the QSL and DQCP from categorical symmetry point of view,and strongly constrain the quantum field theory description of the QSL phase.The phase diagram and critical exponents presented in this paper are of direct relevance to future experiments on frustrated magnets and cold atom systems.

关键词： Tensor network Quantum phase transition Emergent symmetry Quantum spin liquid Deconfined quantum critical point Anisotropic

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Mechanism Design for Ancillary Service Market Considering Social Welfare and Fairness

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1000-1010页

作者： Zhi Wu Yuanxi Wu Wei Gu zheng Xu shu zheng Jingtao Zhao School of Electrical Engineering Southeast UniversityNanjing 210096China NARI Technology Co. Ltd.Nanjing 211106China IEEE CSEE

Increasing penetration of distributed energy resources in the distribution network(DN)is threatening safe operation of the DN,which necessitates setup of the ancillary service market in the DN.In the ancillary service market,distribution system operator(DSO)is responsible for safety of the DN by procuring available capacities of aggregators.Unlike existing studies,this paper proposes a novel market mechanism composed of two parts:choice rule and payment rule.The proposed choice rule simultaneously considers social welfare and fairness,encouraging risk-averse aggregators to participate in the ancillary service market.It is then formulated as a linear programming problem,and a distributed solution using the multi-cut Benders decomposition is presented.Moreover,successful implementation of the choice rule depends on each aggregator’s truthful adoption of private parameters.Therefore,a payment rule is also designed,which is proved to possess two properties:incentive compatibility and individual rationality.Simulation results demonstrate effectiveness of the proposed choice rule on improving fairness and verify properties of the payment rule.

关键词： Aggregator ancillary service market distributed mechanism fairness mechanism design

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Microglial glutaminase 1 mediates chronic restraint stress-induced depression-like behaviors and synaptic damages

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Signal Transduction and Targeted Therapy 2024年第1期9卷 40-43页

作者： Huili Chen Shengyang Fu xiangyu Li Meng Shi Jiazhen Qian shu Zhao Ping Yuan Lu Ding xiaohuan xia Jialin C.zheng Center for Translational Neurodegeneration and Regenerative Therapy Tongji Hospital affiliated to Tongji University School of Medicine200065 ShanghaiChina Department of Cardio-Pulmonary Circulation Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina Translational Research Institute of Brain and Brain-Like Intelligence Shanghai Fourth People’s Hospital affiliated to Tongji University School of Medicine200434 ShanghaiChina

Dear Editor,Major depressive disorder(MDD)is one of the most common psychiatric illnesses that significantly increase the risk of suicide.1 Stress-triggered dysfunctions of microglia have been identified as a commonly occurred pathological feature of MDD.1–3 Microglial dysfunction contributes to the pathogenesis of MDD via immunoresponses/neuroinflammation-mediated neural damage and pathological synapse loss-mediated neural circuit disruption.1 Although the involvement of microglia in MDD has been widely investigated,the molecular mechanisms underlying microglial dysfunction remain largely unknown.Recently,we identified glutaminase 1(Gls1)as one key protein that participates in microglial dysfunction.4–6 Gls1 catalyzes the hydrolysis of glutamine to produce glutamate in the brain.4 Besides its well-known role in excitatory neurotoxicity,we found Gls1 up-regulation in microglia in animal models of Alzheimer’s disease and ischemic stroke.4,7 Gls1 activates microglia to overproduce cytokines and release inflammatory extracellular vesicles,therefore leading to neuroinflammation in animal models of Alzheimer’s disease and ischemic stroke.4–6 More importantly,Gls1 has been found to be up-regulated in the brains of MDD patients,and microglial Gls1 deficiency mitigated LPS-induced depression-like behaviors.8 However,LPS exposure is not an appropriate model to mimic MDD phenotypes,leaving the involvement of Gls1 in MDD an undetermined question.

关键词： involvement inflammation media

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Development and validation of a nomogram to predict allograft survival after pediatric liver transplantation

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World Journal of Pediatrics 2024年第3期20卷 239-249页

作者： Guang-xiang Gu shu-Ting Pan Yi-Chen Fan Chen Chen Qiang xia Department of Liver Surgery Renji HospitalShanghai Jiaotong University School of MedicineNo.160 Pujian RoadPudong New DistrictShanghai 200128China Department of Liver Transplantation Sun Yet-Sen Memorial HospitalSun Yat-Sen UniversityNo.107 Yanjiang West RoadGuangzhou 510080China Clinical Center for Investigation Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina Department of Anesthesiology Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina

Background Liver transplantation is the main treatment for cholestatic liver disease and some metabolic liver diseases in children.However,no accurate prediction model to determine the survival probability of grafts prior to surgery exists.This study aimed to develop an effective prognostic model for allograft survival after pediatric liver transplantation.Methods This retrospective cohort study included 2032 patients who underwent pediatric liver transplantation between January 1,2006,and January 1,2020.A nomogram was developed using Cox regression and validated based on bootstrap sampling.Predictive and discriminatory accuracies were determined using the concordance index and visualized using calibration curves;net benefits were calculated for model comparison.An online Shiny application was developed for easy access to the model.Results Multivariable analysis demonstrated that preoperative diagnosis,recipient age,body weight,graft type,preoperative total bilirubin,interleukin-1β,portal venous blood flow direction,spleen thickness,and the presence of heart disease and cholangitis were independent factors for survival,all of which were selected in the nomogram.Calibration of the nomogram indicated that the 1-,3-,and 5-year predicted survival rates agreed with the actual survival rate.The concordance indices for graft survival at 1,3,and 5 years were 0.776,0.757,and 0.753,respectively,which were significantly higher than those of the Pediatric End-Stage Liver Disease and Child-Pugh scoring systems.The allograft dysfunction risk of a recipient could be easily predicted using the following URL:https://aspelt.***.io/ASPELT/l Conclusion The allograft survival after pediatric liver transplantation(ASPELT)score model can effectively predict the graft survival rate after liver transplantation in children,providing a simple and convenient evaluation method for clinicians and patients.

关键词： Allograft survival Nomogram Pediatric liver transplantation

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Europium-bearing organic framework with excellent X-ray scintillating luminescence

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Journal of Rare Earths 2024年第2期42卷 251-255,I0001页

作者： Yugang Zhang Lanhua Chen xia Wang Wei Liu shu'ao Wang State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123China School of Environmental and Materials Engineering Yantai UniversityYantai264005China

Two europium-bearing organic frameworks,termed as EuTPO-1 and EuTPO-2(H_(3)TPO=tris(4-carboxylphenyI)-phosphineoxide),are reported in this work.A series of characterizations of EuTPO-1and EuTPO-2,such as X-ray crystallography and photoluminescence spectroscopy,was performed to expatiate their structure and physicochemical properties.Both of them are constructed by dimers of the europium-oxygen subunit of [Eu_(2)O_(16)] and TPO molecule.Benefiting from high X-ray stopping attenuation and excellent luminescence efficiency,they emit sufficient luminescence when irradiated with Xrays.Meanwhile,they possess stable light outputs when exposed to high humidities and strong radiation dose,outperforming the commercial scintillator CsI:Tl.This result paves the way for developing new scintillator and enriches the compound of europium-bearing organic framework with X-ray scintillating luminescence.

关键词： Metal-organic frameworks Scintillating material Luminescence efficiency Rare earths

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Middle hepatic vein variation provides a safe path for anterior transection of hepatocellular carcinoma in caudate lobe

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 438-440页

作者： Bing-Yi Lin Qi-Jun Zhang Zhe Yang shu-Sen zheng Department of Hepatobiliary and Pancreatic Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Thyroid Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Division of Hepatobiliary Pancreatic Surgery Shulan(Hangzhou)HospitalZhejiang Shuren University School of MedicineHangzhou 310000China

To the Editor:Hepatocellular carcinoma(HCC)is one of the main causes of cancer related death worldwide,and new cases are expected to continue to increase in future[1].Surgical resection is still the best way to remove the tumor and improve patient’s prognosis.However,resection of caudate lobe often presents a technical challenge,even to accomplished hepatic surgeons.Caudate lobe is located anterior to the inferior vena cava(IVC)and posterior to the bifurcation of the portal vein(PV),generally consists of three regions:the paracaval portion,the left Spiegel lobe and the process portion[2].The anatomy of the paracaval portion includes the liver parenchyma ventral to the hepatic IVC and the area between the Spiegel lobe and the right lobe adjacent to the middle hepatic vein(MHV)ventrally,which was classified by Couinaud as segment IX[3].Here,we presented a case of HCC with successful downstaging therapy,as well as variation of MHV,which provides a safe path for anterior transection of segment IX.

关键词： hepatic anatomy Middle

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YOLOv5ST:A Lightweight and Fast Scene Text Detector

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Computers, Materials & Continua 2024年第4期79卷 909-926页

作者： Yiwei Liu Yingnan Zhao Yi Chen zheng Hu Min xia School of Computer and Science Nanjing University of Information Science and TechnologyNanjing210044China School of Automation Nanjing University of Information Science and TechnologyNanjing210044China

Scene text detection is an important task in computer vision.In this paper,we present YOLOv5 Scene Text(YOLOv5ST),an optimized architecture based on YOLOv5 v6.0 tailored for fast scene text detection.Our primary goal is to enhance inference speed without sacrificing significant detection accuracy,thereby enabling robust performance on resource-constrained devices like drones,closed-circuit television cameras,and other embedded systems.To achieve this,we propose key modifications to the network architecture to lighten the original backbone and improve feature aggregation,including replacing standard convolution with depth-wise convolution,adopting the C2 sequence module in place of C3,employing Spatial Pyramid Pooling Global(SPPG)instead of Spatial Pyramid Pooling Fast(SPPF)and integrating Bi-directional Feature Pyramid Network(BiFPN)into the neck.Experimental results demonstrate a remarkable 26%improvement in inference speed compared to the baseline,with only marginal reductions of 1.6%and 4.2%in mean average precision(mAP)at the intersection over union(IoU)thresholds of 0.5 and 0.5:0.95,respectively.Our work represents a significant advancement in scene text detection,striking a balance between speed and accuracy,making it well-suited for performance-constrained environments.

关键词： Scene text detection YOLOv5 lightweight object detection

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Einstein-Bumblebee引力理论中的Kerr-Sen-like黑洞玻色子隧穿辐射

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物理学报 2024年第4期73卷 60-68页

作者：谭霞杨树政齐鲁师范学院物理与电子工程学院济南250200 西华师范大学物理与天文学院南充637002

Lorentz-breaking理论不仅对弯曲时空背景有影响,而且对于在弯曲时空中的玻色子和费米子的动力学方程都有一定的修正.因此,我们需要在不同的黑洞时空中对玻色子和费米子的量子隧穿辐射进行适当的修正.从而得到经过Lorentz-breaking理论... 详细信息

Lorentz-breaking理论不仅对弯曲时空背景有影响,而且对于在弯曲时空中的玻色子和费米子的动力学方程都有一定的修正.因此,我们需要在不同的黑洞时空中对玻色子和费米子的量子隧穿辐射进行适当的修正.从而得到经过Lorentz-breaking理论修正后的黑洞Hawking温度等物理量的新表达式及其物理意义.本文根据Einstein-Bumblebee引力理论中得到的Kerr-Sen-like(KSL)黑洞时空度规,在标量场作用量中引入aether-like场矢量修正项和弯曲时空中的d’Alembert算符并应用弯曲时空中的变分原理,研究了此时空度规中的Lorentz-breaking修正项及KSL时空中自旋为零的含有Lorentz-breaking修正项的玻色子动力学方程的新形式.通过正确选择与KSL时空度规相对应的aether-like场矢量,求解修正的玻色子动力学方程,得到了修正的量子隧穿率,并在此基础上研究了含有Lorentz-breaking修正项的此黑洞的Hawking温度和Bekenstein-Hawking熵.此外,还研究了Lorentz-breaking效应对玻色子正、负能级分布及其能级交错的最大值的影响,从而得出此黑洞时空中的量子非热辐射的条件.最后对所得到的一系列结果的物理意义进行了深入的讨论.

关键词： Lorentz-breaking Einstein-Bumblebee引力理论 Kerr-Sen-like黑洞 Bekenstein-Hawking熵

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Comment on“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 109-110页

作者： xiang-Yan Liu Yun-Yang Xu Ze xiang shu-Sen zheng shulan(Hangzhou)Hospital Affiliated to Zhejiang shuren University shulan International Medical College Hangzhou 310015China Zhejiang University School of Medicine Hangzhou 310009China

To the Editor:We read with great interest the article by Schulze et al.entitled“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”[1].It is the first single-center report including over 500 fully robotic donor hepatectomies.For the donors,the overall complication rate was 6.4%(n=32).Postoperative self-limiting bleeding(0.4%)and bile leakage from the resection plane(1.8%)were rare.

关键词： robotic Robotic center

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