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Characteristics of Emission Non-nulling Pulsars Through Simulation

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Research in Astronomy and Astrophysics 2024年第4期24卷 91-102页

作者： Rai yuen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China SIfA School of PhysicsUniversity of SydneySydneyNSW2006Australia

We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar *** from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is ***(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is ***(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the *** find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and ***,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime.

关键词： radiation mechanisms:non thermal stars:neutron (stars:)pulsars:general

Prostate health index can stratify patients with Prostate Imaging Reporting and Data System score 3 lesions on magnetic resonance imaging to reduce prostate biopsies

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Asian Journal of Andrology 2024年第1期26卷 20-24页

作者： John Shung-Lai Leung Wai-Kit Ma Brian Sze-Ho Ho Stacia Tsun-Tsun Chun Rong Na Yongle Zhan Chi-yuen ng Chi-Ho Ip Ada Tsui-Lin ng Yiu-Chung Lam Division of Urology Department of SurgeryQueen Mary HospitalUniversity of Hong KongHong KongChina Division of Urology Department of SurgeryPrincess Margaret HospitalHongKongChina

We aim to evaluate prostate health index as an additional risk-stratification tool in patients with Prostate Imaging Reporting and Data System score 3 lesions on multiparametric magnetic resonance *** with biochemical or clinical suspicion of having prostate cancer who underwent multiparametric magnetic resonance imaging in two tertiary centers(Queen Mary Hospital and Princess Margaret Hospital,Hong Kong,China)between January 2017 and June 2022 were ***-magnetic resonance imaging fusion biopsies were performed after prostate health index *** who only had Prostate Imaging Reporting and Data System score 3 lesions were further stratified into four prostate health index risk groups and the cancer detection rates were *** of the 747 patients,47.3%had Prostate Imaging Reporting and Data System score 3 lesions *** detection rate of clinically significant prostate cancer in this group was 15.0%.The cancer detection rates of clinically significant prostate cancer had statistically significant differences:5.3%in prostate health indexng the patients,26.9%could have avoided a biopsy with a prostate health indexng clinically significant prostate *** health index could be used as an additional risk stratification tool for patients with Prostate Imaging Reporting and Data System score 3 *** could be avoided in patients with low prostate health index,with a small risk of missing clinically significant prostate cancer.

关键词： biopsy fusion biopsy magnetic resonance imaging prostate cancer prostate health index

Asymptotics for the joint tail probability of bidimensional randomly weighted sums with applications to insurance

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Science China Mathematics 2024年第1期67卷 163-186页

作者： Yang Yang Shaoying Chen Kam Chuen yuen School of Statistics and Data Science Nanjing Audit UniversityNanjing 211815China Department of Statistics and Actuarial Science The University of Hong KongHong Kong 999077China

This paper studies the joint tail behavior of two randomly weighted sums∑_(i=1)^(m)Θ_(i)X_(i)and∑_(j=1)^(n)θ_(j)Y_(j)for some m,n∈N∪{∞},in which the primary random variables{X_(i);i∈N}and{Y_(i);i∈N},respectively,are real-valued,dependent and heavy-tailed,while the random weights{Θi,θi;i∈N}are nonnegative and arbitrarily dependent,but the three sequences{X_(i);i∈N},{Y_(i);i∈N}and{Θ_(i),θ_(i);i∈N}are mutually *** two types of weak dependence assumptions on the heavy-tailed primary random variables and some mild moment conditions on the random weights,we establish some(uniformly)asymptotic formulas for the joint tail probability of the two randomly weighted sums,expressing the insensitivity with respect to the underlying weak dependence *** applications,we consider both discrete-time and continuous-time insurance risk models,and obtain some asymptotic results for ruin probabilities.

关键词： asymptotic joint tail behavior randomly weighted sum heavy-tailed distribution dependence insurance risk model

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Targeting calcium signaling in Alzheimer’s disease: challenges and promising therapeutic avenues

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Neural Regeneration Research 2024年第3期19卷 501-502页

作者： LinLin Song YongPei Tang Betty yuen Kwan Law Neher’s Biophysics Laboratory for Innovative Drug Discovery State Key Laboratory of Quality Research in Chinese MedicineMacao University of Science and TechnologyMacao Special Administration RegionChina

The critical role of calcium dyshomeostasis in the pathogenesis of Alzheimer’s disease(AD):AD is a progressive neurodegenerative disease characterized by cognitive decline,memory impairment,and behavioral *** an estimated 50 million people being affected worldwide,the incidence of AD is constantly increasing *** hallmark of AD is the accumulation of amyloid-beta protein(Aβ)in the form of amyloid plaques and hyperphosphorylated tau protein in the form of neurofibrillary ***,increasing evidence suggests that calcium ion(Ca2+)dysregulation also plays a crucial role in the pathogenesis of AD(Calvo-Rodriguez and Bacskai,2021).As a key second messenger,Ca2+regulates a wide range of cellular processes,including the release of neurotransmitters,gene expression,and cell ***^(2+)also regulates the activity of Calcium/calmodulin-dependent protein kinase II,which is critical for synaptic plasticity,learning,and memory(Kaushik et al.,2022).Alternation in the Ca^(2+)signal is an early event in the pathogenesis of AD,which can lead to synaptic dysfunction,neuronal loss,and cognitive impairment.

关键词： Alzheimer homeostasis globally

Dysfunction of synaptic endocytic trafficking in Parkinson's disease

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Neural Regeneration Research 2024年第12期19卷 2649-2660页

作者： Xin Yi ng Mian Cao Programme in Neuroscience and Behavioural Disorders Duke-NUS Medical SchoolSingaporeSingapore Department of Physiology National University of SingaporeSingaporeSingapore

Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the *** precise reasons behind the specific degeneration of these dopamine neurons remain largely *** investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's ***,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis *** suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"***,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively *** models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical *** this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PARK19)and synaptojanin 1(SYNJ1/PARK20).The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic ***,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease *** will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PARK1/4),Parkin(PARK2),and LRRK2(PARK

关键词： autophagy auxilin/PARK19 clathrin-mediated endocytosis dopamine neurons neurodegeneration nigrostriatal pathway Parkinson's disease synaptic vesicle recycling synaptojanin1/PARK20

Process,Material,and Regulatory Considerations for 3D Printed Medical Devices and Tissue Constructs

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Engineering 2024年第5期36卷 146-166页

作者： Wei Long ng Jia An Chee Kai Chua Singapore Centre for 3D Printing(SC3DP) School of Mechanical and Aerospace EngineeringNanyang Technological UniversitySingapore 639798Singapore Centre for Healthcare Education Entrepreneurship and Research@SUTD(CHEERS)Singapore University of Technology and DesignSingapore 487372Singapore

Three-dimensional(3D)printing is a highly automated platform that facilitates material deposition in a layer-by-layer approach to fabricate pre-defined 3D complex structures on *** is a highly promising technique for the fabrication of personalized medical devices or even patient-specific tissue *** type of 3D printing technique has its unique advantages and limitations,and the selection of a suitable 3D printing technique is highly dependent on its intended *** this review paper,we present and highlight some of the critical processes(printing parameters,build orientation,build location,and support structures),material(batch-to-batch consistency,recycling,protein adsorption,biocompatibility,and degradation properties),and regulatory considerations(sterility and mechanical properties)for 3D printing of personalized medical *** goal of this review paper is to provide the readers with a good understanding of the various key considerations(process,material,and regulatory)in 3D printing,which are critical for the fabrication of improved patient-specific 3D printed medical devices and tissue constructs.

关键词： 3D printing Bioprinting Biofabrication Medical devices Tissue constructs

Spreadsheet quality assurance:a literature review

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Frontiers of Computer Science 2024年第2期18卷 61-82页

作者： Pak-Lok POON Man Fai LAU yuen Tak YU Sau-Fun TAng School of Engineering and Technology Central Queensland UniversityMelbourne 3000Australia Department of Computing Technologies Swinburne University of TechnologyHawthorn 3122Australia Department of Computer Science City University of Hong KongHong Kong SAR 999077China The Royal Victorian Eye and Ear Hospital East Melbourne 3002Australia

Spreadsheets are very common for information processing to support decision making by both professional developers and non-technical end ***,business intelligence and artificial intelligence are increasingly popular in the industry nowadays,where spreadsheets have been used as,or integrated into,intelligent or expert systems in various application ***,it has been repeatedly reported that faults often exist in operational spreadsheets,which could severely compromise the quality of conclusions and decisions based on the *** a view to systematically examining this problem via survey of existing work,we have conducted a comprehensive literature review on the quality issues and related techniques of spreadsheets over a 35.5-year period(from January 1987 to June 2022)for target journals and a 10.5-year period(from January 2012 to June 2022)for target *** other findings,two major ones are:(a)Spreadsheet quality is best addressed throughout the whole spreadsheet life cycle,rather than just focusing on a few specific stages of the life cycle.(b)Relatively more studies focus on spreadsheet testing and debugging(related to fault detection and removal)when compared with spreadsheet specification,modeling,and design(related to development).As prevention is better than cure,more research should be performed on the early stages of the spreadsheet life *** by our comprehensive review,we have identified the major research gaps as well as highlighted key research directions for future work in the area.

关键词： decision support system end-user computing end-user programming Excel spreadsheet

Large-scale manufacturing of functional single-atom ink for convenient glucose sensing

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Nano Research 2024年第8期17卷 7256-7263页

作者： Muyu Yan Xiaofei Zhu Can Xiong Xiao Han Zhenggang Xue yuen Wu Department of Endocrinology Institute of Endocrine and Metabolic DiseasesThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Deep Space Exploration Laboratory University of Science and Technology of ChinaHefei 230026China NEST Laboratory Department of PhysicsDepartment of ChemistryCollege of ScienceShanghai UniversityShanghai 200444China Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Printing techniques hold great potential in the manufacture of electronics such as sensors,micro-supercapacitors,and flexible ***,developing large-scale functional conductive inks with appropriate rheological properties and active components still remains a ***,through optimizing the formulations of ink,iron single sites supported N-doped carbon black(Fe_(1)-NC)inks can serve as both conductive electrodes and high-reactive catalysts to realize convenient glucose detection,which pronouncedly reduces the dosage of enzyme and simplifies the sensors *** detail,utilizing in-situ pyrolysis method,Fe_(1)-NC single-atom catalysts(SACs)are prepared in bulk(dekagram-level).The batched Fe_(1)-NC SACs materials can be uniformly mixed with modulated ink to realize the screen printing with high resolution and ***,the whole scalable preparation and ink-functional process can be extended to various metals(including Co,Ni,Cu,and Mn).The introduction of highly active Fe_(1)-NC sites reduces the amount of enzyme used in glucose detection by at least 50%,contributing to the cost reduction of *** strategy in harnessing the SACs onto the carbon inks thus provides a broad prospect for the low-cost and large-scale printing of sensitive sensing devices.

关键词： large-scale manufacturing single-atom inks screen printing glucose sensing low enzyme dosage

A prospective cohort of men with localized prostate cancer on active surveillance protocol in Hong Kong,China:what did we learn?

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Asian Journal of Andrology 2024年第3期26卷 245-249页

作者： Xiaobo Wu Ivan Ching-Ho Ko Cindy Yeuk-Lam Hong Samuel Chi-Hang Yee Jeremy yuen-Chun Teoh Samson Yun-Sang Chan Ho-Man Tam Chi-Kwok Chan Chi-Fai ng Peter Ka-Fung Chiu SH Ho Urology Centre Department of SurgeryFaculty of MedicineThe Chinese University of Hong KongHong KongChina

This study aimed to report the outcomes of active surveillance(AS)in the management of low-risk prostate cancer(PCa).It recruited87 men who were prospectively followed up according to the Prostate Cancer Research International Active Surveillance(PRIAS)protocol with local adaptation at SH Ho Urology Centre,Prince of Wales Hospital,Hong Kong,*** investigated the predictorsof disease progression and found that baseline prostate-specific antigen density(PSAD)and the presence of the highest ProstateImaging-Reporting and Data System(PI-RADS)score 5 lesion on magnetic resonance imaging(MRI)are significantly correlatedwith disease ***,men with PSAD>0.2 ng ml^(−2)or PI-RADS 4 or 5 lesions had significantly worse upgradingfree survival compared to those with PSAD≤0.2 ng ml−2 and PI-RADS 2 or 3 *** study concludes that AS is a safe andeffective management strategy for selected patients to defer radical treatment and that most disease progression can be detectedafter the first repeated *** combination of PSAD>0.2 ng ml^(−2)and PI-RADS 4 or 5 lesions may serve as a useful predictorof early disease progression and provide a guide to optimize follow-up protocols for men in different risk groups.

关键词： active surveillance cohort localized prostate cancer