Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This co...Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This condition is thought to affect approximately 2%of the Western population,with diagnosis peaking in early adulthood[2].Vitamin D,a fat-soluble vitamin,is essential for phospho-calcium metabolism,calcium homeostasis,and bone health.展开更多
Accurate fission cross-sectional data for actinide nuclides are critical for nuclear energy,astrophysics,and defense applications.Traditional detectors,such as fission chambers,face limitations in achieving sub-3% unc...Accurate fission cross-sectional data for actinide nuclides are critical for nuclear energy,astrophysics,and defense applications.Traditional detectors,such as fission chambers,face limitations in achieving sub-3% uncertainty owing to particle identification challenges and dynamic range constraints.The time projection chamber(TPC)can record both the energy deposition dE/dx and the three-dimensional track of an event,providing the ability to identify particles and fission fragments.Based on this characteristic,we developed a novel TPC,INPC-TPC,featuring a symmetrical dual-chamber structure and gas electron multiplier(GEM)-based readout technology.The dual-chamber design isolates fission fragments and recoils protons,thereby reducing the dynamic range requirements of a single chamber,whereas the GEM ensures high spatial resolution and stable gain.Experiments conducted at the Chinese Spallation Neutron Source(CSNS)Back-n white neutron beamline validated the performance of the proposed detector.The INPC-TPC demonstrated effective fission fragment identification through particle energy-length correlation measurements and accurately measured the neutron beam spot size with a diameter relative error of<2%.The results highlight the capability of the system to achieve high-precision measurements of neutroninduced fission cross sections,particularly for ^(235)U and ^(238)U.展开更多
Radar cross section(RCS)plays a critical role in modeling target scattering characteristics and enhancing the precision of target detection and localization in integrated sensing and communication(ISAC)systems.This pa...Radar cross section(RCS)plays a critical role in modeling target scattering characteristics and enhancing the precision of target detection and localization in integrated sensing and communication(ISAC)systems.This paper investigates the human body RCS at 26 GHz via multiangle channel measurements under different clothing conditions.Based on calibrated electromagnetic(EM)parameters,the RCS characteristics of the human body in far-field conditions are analyzed using ray-tracing(RT)simulations.Some suggestions for the design of ISAC systems are also discussed.The results provide a solid theoretical foundation and practical reference for the modeling of target scattering characteristics for ISAC channels.展开更多
Here,we report the spin-orbit state-resolved differential cross sections(DCSs)for the prototype barrierless reaction S(^(1)D)+HD.Both product channels,namely H+SD(^(2)Π_(3/2,1/2))and D+SH(^(2)Π_(3/2,1/2)),were measu...Here,we report the spin-orbit state-resolved differential cross sections(DCSs)for the prototype barrierless reaction S(^(1)D)+HD.Both product channels,namely H+SD(^(2)Π_(3/2,1/2))and D+SH(^(2)Π_(3/2,1/2)),were measured by high-resolution crossed molecular beam experiments.The DCSs of the two product channels show an overall forward-backward symmetry,in accordance with statistical model predictions.However,the DCSs for different spin-orbit manifolds show different preferences in forward or backward scattering directions at the same collision energies.This study reveals that,even though the title reaction proceeds via the long-lived complex mechanism,the spin-orbit coupling effects in the product channels play an important role in the reaction process.展开更多
The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O_(2)^...The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O_(2)^(2+),O_(2)^(2+)O^(+),O^(2+),and their total)and two Coulomb explosion channels(O^(+)+O^(+)and O^(2+)+O^(+))are obtained by putting the data of O^(2+)on the scale of Ar+from O_(2)and Ar gases mixed with a fixed relative flow ratio of 1:1.The experimental errors are assessed by taking uncertainties of various factors into account.The present absolute cross sections are well consistent with the previous data in the overlapped energy range below 1000 eV.展开更多
To overcome the difficulty and high cost of some specific isotopic targets,a substitution method was proposed to measure the cross section of the(γ,n)reactions.Considering that the natural copper element(^(nat)Cu)onl...To overcome the difficulty and high cost of some specific isotopic targets,a substitution method was proposed to measure the cross section of the(γ,n)reactions.Considering that the natural copper element(^(nat)Cu)only has^(63)Cu and^(65)Cu isotopes,the^(65)Cu(γ,n)^(64)Cu reaction was taken as an example to test the substitution method.Using quasi-monoenergeticγbeams provided by the Shanghai Laser Electron Gamma Source(SLEGS)of the Shanghai Synchrotron Radiation Facility(SSRF),^(nat)Cu(γ,n)was measured from E_(γ)=11.09 MeV to 17.87 MeV.Furthermore,based on the^(63)Cu(γ,n)reaction measured using the same experimental setup at SLEGS,^(65)Cu(γ,n)^(64)Cu was extracted using the substitution method.The abundance variation of natural copper,showing a significant influence on the cross section,was also investigated.The results were compared to the existing experimental data measured by bremsstrahlung and positron annihilation in-flight sources,and the TALYS 2.0 predictions.Theγstrength function(γSF)of^(65)Cu was obtained from the^(65)Cu(γ,n)data,and the reaction cross section of^(64)Cu(n,γ)was further calculated.展开更多
Inelastic collisions are the dominant cause of energy loss in radiotherapy.In the energy range around the Bragg peak,single ionization(SI)and single-electron capture(SC)are the primary inelastic collisions that lead t...Inelastic collisions are the dominant cause of energy loss in radiotherapy.In the energy range around the Bragg peak,single ionization(SI)and single-electron capture(SC)are the primary inelastic collisions that lead to energy loss.This study employs the classical trajectory Monte Carlo method to study the SI and SC processes of H_(2)O molecules using He^(2+) and C^(6+) projectiles in the energy range of 10 keV/u to 10 MeV/u.The total cross sections,single differential cross sections,impact parameter dependence of SI and SC,and fragmentation cross sections were investigated.Results illustrate that the cross section for SI is the highest when the projectile energy is close to the Bragg peak energy.When the projectile energy is below the Bragg peak energy,the ionized electrons in the forward direction dominate,and the removal of electrons can be associated with large impact parameters.As the projectile energy increases,the emission angle of the electrons gradually transitions from small angles(60°~120°)to large angles(60°~120°),and the removal of electrons is associated with small impact parameters.The energy distributions of the ionized electron are similar when the projectile energy is equal to,below or above the Bragg peak energy.The fragmentation cross sections after SI and SC in the energy range around the Bragg peak were also estimated.展开更多
Rapid population aging has led to an increased focus on age-related conditions such as sarcopenia.causing loss of muscle mass and strength^([1,2]). Sarcopenia is associated with adverse outcomes,including falls, funct...Rapid population aging has led to an increased focus on age-related conditions such as sarcopenia.causing loss of muscle mass and strength^([1,2]). Sarcopenia is associated with adverse outcomes,including falls, functional decline, frailty, and mortality, which can lower the quality of life and shorten lifespan^([1,2]).展开更多
Dear Editor,Growing clinical evidence shows that brain disorders are heterogeneous in phenotype,genetics,and neuropathology[1].Diagnosis and treatment tend to be affected by symptom presentation and the heterogeneity ...Dear Editor,Growing clinical evidence shows that brain disorders are heterogeneous in phenotype,genetics,and neuropathology[1].Diagnosis and treatment tend to be affected by symptom presentation and the heterogeneity of pathology,potentially hindering clinical trials in the development of medical treatment.Brain-based subtyping studies utilize magnetic resonance imaging(MRI)and data-driven methods to discover the subtypes of diseases,providing a new perspective on disease heterogeneity.展开更多
Dear Editor,I am writing in response to the article“Assessment of nurses’workplace silence behavior motives:A cross-sectional study”by Alhojairi et al.published in the September 2024 issue of the International Jour...Dear Editor,I am writing in response to the article“Assessment of nurses’workplace silence behavior motives:A cross-sectional study”by Alhojairi et al.published in the September 2024 issue of the International Journal of Nursing Sciences[1].This is a letter written by a nurse with 10 years of clinical work experience and a personal interest in team dynamics.I appreciate the authors'recommendations on mitigating workplace silence among nurses to enhance clinical work development,and I believe their proposals could be expanded further.展开更多
BACKGROUND Transition is a critical period for adolescents as they begin to assume responsibility for their own health.Similarly,the shift from pediatric to adult healthcare represents a vulnerable phase,marked by uni...BACKGROUND Transition is a critical period for adolescents as they begin to assume responsibility for their own health.Similarly,the shift from pediatric to adult healthcare represents a vulnerable phase,marked by unique challenges in adolescent health care.Despite its importance,only a few studies have explored healthcare transition among adolescents in Uganda.AIM To identify factors associated with the transition to adult human immunodeficiency virus(HIV)-centered care among adolescents attending HIV/AIDS clinics in Uganda.METHODS A cross-sectional mixed-methods study was conducted among 265 adolescents,randomly selected from three antiretroviral therapy(ART)clinics,using a structured questionnaire.Focus group discussions and key informant interviews were conducted.Individuals aged 10-20 years who were actively enrolled in the ART program between January 4,2022 and January 30,2023 were recruited.The primary outcome of interest was the transition to adult care.Bivariate and multivariate analyses were performed for quantitative data,while content analysis was used to analyze qualitative data.RESULTS The prevalence of transition to adult care was 40.6%.Most participants were male(53.6%)and fell within the 13-15 age group(35.6%).Multivariate logistic regression analysis identified several factors significantly associated with transition to adult care:Age group 10-12 years[prevalence ratio(PR)=2.525,95%CI:2.121-2.944,P=0.002],Age group 13-15 years(PR=1.900,95%CI:1.196-3.416,P=0.001),successful viral load suppression(PR=1.534,95%CI:1.173-1.648,P=0.016),disclosure of HIV status to relatives(PR=5.001,95%CI:3.411-3.611,P=0.000),being prepared for transitioning(PR=5.417,95%CI:3.468-7.135,P=0.041)and having skilled pediatric caregivers(PR=3.724,95%CI:2.084-4.105,P=0.005).CONCLUSION Transition to adult care among adolescents was low.Improving transition outcomes may require strengthening individual support within the family context and integrating transition-focused care into existing specialized clinical settings to enhance the delivery of adolescent-friendly services.展开更多
Arterial stiffness is considered an important indicator reflecting age-related changes in the vascular wall[1]and the risk of developing comorbidities,[2]primarily cardiovascular diseases.[3]Cardiovascular diseases re...Arterial stiffness is considered an important indicator reflecting age-related changes in the vascular wall[1]and the risk of developing comorbidities,[2]primarily cardiovascular diseases.[3]Cardiovascular diseases remain the leading cause of death worldwide.Many factors influence the rate of arterial aging.Research results have confirmed that arterial wall stiffness increases with an increasing number of risk factors,[4]as each of them acts independently through various mechanisms,adversely affecting the structure and function of the cardiovascular system.展开更多
The neutron capture cross section for^(165)Ho was measured at the backstreaming white neutron beam line(Back-n)of the China Spallation Neutron Source(CSNS)using total energy detection systems,composed of a set of four...The neutron capture cross section for^(165)Ho was measured at the backstreaming white neutron beam line(Back-n)of the China Spallation Neutron Source(CSNS)using total energy detection systems,composed of a set of four C_(6)D_(6)scintillator detectors coupled with pulse height weighting techniques.The resonance parameters were extracted using the multilevel multichannel R-matrix code SAMMY to fit the measured capture yields of the^(165)Ho(n,γ)reaction in the neutron energy range below100 eV.Subsequently,the resonance region’s capture cross sections were reconstructed based on the obtained parameters.Furthermore,the unresolved resonance average cross section of the^(165)Ho(n,γ)reaction was determined relative to that of the standard sample^(197)Au within the neutron energy range of 2 keV to 1 MeV.The experimental data were compared with the recommended nuclear data from the ENDF/B-VIII.0 library,as well as with results of calculations performed using the TALYS-1.9 code.The comparison revealed agreement between the measured^(165)Ho(n,γ)cross sections and these data.The present results are crucial for evaluating the^(165)Ho neutron capture cross section and thus enhance the quality of evaluated nuclear data libraries.They provide valuable guidance for nuclear theoretical models and nuclear astrophysical studies.展开更多
The radioisotope actinium-225(^(225)Ac)has been successfully used for targeted alpha therapy in preclinical and clinical applications because of its excellent nuclear characteristics.Medium-and high-energy proton-spal...The radioisotope actinium-225(^(225)Ac)has been successfully used for targeted alpha therapy in preclinical and clinical applications because of its excellent nuclear characteristics.Medium-and high-energy proton-spallation reactions on thorium are the most important methods for producing^(225)Ac.This study examines the possibility of producing^(225)Ac by irradiating thorium oxide with medium-energy protons.Thorium-oxide sheets were irradiated with 40-,50-,60-,70-,and 80-Me V protons on the Associated Proton-beam Experiment Platform(APEP)of the China Spallation Neutron Source(CSNS).The cross sections for the formation of^(225)Ac were measured using the activation method and offline gamma-ray spectrometric technique.The experimental results were compared with the existing data from EXFOR as well as the theoretical data from the TALYS-based evaluated nuclear-data library.Based on the experimental cross section and theoretical calculations,the production yield of^(225)Ac in the irradiated thorium targets was examined.The results showed that APEP can produce sufficient quantities of^(225)Ac for purification and clinical therapy.This work is the first measurement of proton-induced nuclearreaction cross sections at the CSNS APEP.展开更多
This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are ob...This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are obtained.Pore structures are segmented by the U-shaped network(U-Net)neural network integrated with the Canny edge detection operator,ensuring accurate pore delineation and edge extraction.The trained U-Net achieves 98.55%accuracy.The 2D data are superimposed and processed into 3D point clouds,enabling reconstruction of the pore structure and aluminum skeleton.Analysis of pore 01 shows the cross-sectional area initially increases,and then decreases with milling depth,with a uniform point distribution of 40 per layer.The reconstructed model exhibits a porosity of 77.5%,with section overlap rates between the 2D pore segmentation and the reconstructed model exceeding 96%,confirming high fidelity.Equivalent sphere diameters decrease with size,averaging 1.95 mm.Compression simulations reveal that the stress-strain curve of the 3D reconstruction model of aluminum foam exhibits fluctuations,and the stresses in the reconstruction model concentrate on thin cell walls,leading to localized deformations.This method accurately restores the aluminum foam’s complex internal structure,improving reconstruction preci-sion and simulation reliability.The approach offers a cost-efficient,high-precision technique for optimizing material performance in engineering applications.展开更多
Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical a...Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical analysis of roof structures and adopts a multivariate nonlinear analysis approach to explore the synergistic load-bearing effects within the'coal pillar-support-backfill body'system during the fill and re-mining processes above these roadways.The findings demonstrate that backfill mining significantly reduces stress concentrations in coal pillars and reduces excessive bending moments in roofs near abandoned roadways.The roof deflection equation incorporates three critical factors affecting stability during backfill mining:the width of the coal pillar(L_(3)),the working resistance of the support(q_(z)),and the elastic foundation coefficient of the backfill material(kcÞ.Under single-factor conditions,the impact sequence on roof stability in the coal pillar zone is·k_(c)>L_(3)>q_(z).Further,multivariate nonlinear analysis reveals the interactions within the'coal-support-backfill'structure,indicating that in terms of roof control,the interaction terms are ordered as L_(3)·k_(c)>q_(z)·k_(c)>L_(3)q_(z).Therefore,priority should be given to adjusting the coal pillar width and backfill strength,followed by modifications to the support resistance and backfill strength during the recovery of abandoned roadways.An improved understanding of these interactions will help optimize strategies for the recovery of residual coal through abandoned roadways,thereby enhancing the stability and safety of mining operations under complex geological conditions.展开更多
Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods ofte...Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods often overlook the multi-scale nature of bird targets,limiting their ability to capture rich contextual information across different scales.To address this,we propose a cross-dimensional attention network(CDA-Net)for bird detection that integrates spatial and channel information to improve species recognition.The proposed CDA-Net partitions feature maps into multiple channel wise sub-features.Spatial and channel attention are applied to each subfeature,and the resulting features are fused using the Hadamard product.The fused features are then forwarded to the detection head to generate the final detection results.This approach effectively captures and integrates information across spatial and channel dimensions.Experiments on our self-constructed Nanhai Wetland Waterbird Dataset and the public CUB-200-2011 dataset yield precision scores of 91.32%and 81.99%,respectively,outperforming existing methods.Our approach effectively handles scale variation in bird detection and provides a valuable tool for advancing automated wetland waterbird monitoring.展开更多
Let M be a compact n-manifold of positive sectional curvature.We will review classical results on the fundamental group of M,a motivation on the c(n)-cyclic conjecture that the fundamental group of M contains a cyclic...Let M be a compact n-manifold of positive sectional curvature.We will review classical results on the fundamental group of M,a motivation on the c(n)-cyclic conjecture that the fundamental group of M contains a cyclic subgroup of index bounded above by c(n),a constant depending only on n,and we will survey partial results(up to date)on the c(n)-cyclic conjecture.展开更多
In recent years,the field of neuroimmunology has witnessed a profound paradigm shift.Research has expanded beyond the traditional focus on the central nervous system to unravel the dynamic interplay between peripheral...In recent years,the field of neuroimmunology has witnessed a profound paradigm shift.Research has expanded beyond the traditional focus on the central nervous system to unravel the dynamic interplay between peripheral immunity and neural networks.Cutting-edge methodologies have unmasked a tripartite communication axis enabling peripheral immune signals to mediate the CNS:(1)neural communication via vagal afferents,(2)humoral signaling through circumventricular organ cytokine diffusion,and(3)cellular interactions involving bone marrow-derived macrophages[1].展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.82573974 and 82373475)to Z.Y.
文摘Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This condition is thought to affect approximately 2%of the Western population,with diagnosis peaking in early adulthood[2].Vitamin D,a fat-soluble vitamin,is essential for phospho-calcium metabolism,calcium homeostasis,and bone health.
基金supported by the auspices of the Youth Doctoral Talent Incubation Program of the Second Affiliated Hospital of Army Medical University(No.2024YQB060)。
文摘Accurate fission cross-sectional data for actinide nuclides are critical for nuclear energy,astrophysics,and defense applications.Traditional detectors,such as fission chambers,face limitations in achieving sub-3% uncertainty owing to particle identification challenges and dynamic range constraints.The time projection chamber(TPC)can record both the energy deposition dE/dx and the three-dimensional track of an event,providing the ability to identify particles and fission fragments.Based on this characteristic,we developed a novel TPC,INPC-TPC,featuring a symmetrical dual-chamber structure and gas electron multiplier(GEM)-based readout technology.The dual-chamber design isolates fission fragments and recoils protons,thereby reducing the dynamic range requirements of a single chamber,whereas the GEM ensures high spatial resolution and stable gain.Experiments conducted at the Chinese Spallation Neutron Source(CSNS)Back-n white neutron beamline validated the performance of the proposed detector.The INPC-TPC demonstrated effective fission fragment identification through particle energy-length correlation measurements and accurately measured the neutron beam spot size with a diameter relative error of<2%.The results highlight the capability of the system to achieve high-precision measurements of neutroninduced fission cross sections,particularly for ^(235)U and ^(238)U.
基金supported by the National Natural Science Foundation of China under Grant No.62271043Ministry of Education of China under Grant No.8091B032123Beijing Natural Science Foundation under Grant No.L212029。
文摘Radar cross section(RCS)plays a critical role in modeling target scattering characteristics and enhancing the precision of target detection and localization in integrated sensing and communication(ISAC)systems.This paper investigates the human body RCS at 26 GHz via multiangle channel measurements under different clothing conditions.Based on calibrated electromagnetic(EM)parameters,the RCS characteristics of the human body in far-field conditions are analyzed using ray-tracing(RT)simulations.Some suggestions for the design of ISAC systems are also discussed.The results provide a solid theoretical foundation and practical reference for the modeling of target scattering characteristics for ISAC channels.
基金supported by the National Natural Science Foundation of China(Nos.92476207,22288201)the Chinese Academy of Sciences(No.XBD0970202)+2 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0303300)the Shenzhen Science and Technology Innovation Committee(No.20220814164755002)the Guangdong Innovative&Entrepreneurial Research Team Program(Nos.2019ZT08L455,2019JC01X091).
文摘Here,we report the spin-orbit state-resolved differential cross sections(DCSs)for the prototype barrierless reaction S(^(1)D)+HD.Both product channels,namely H+SD(^(2)Π_(3/2,1/2))and D+SH(^(2)Π_(3/2,1/2)),were measured by high-resolution crossed molecular beam experiments.The DCSs of the two product channels show an overall forward-backward symmetry,in accordance with statistical model predictions.However,the DCSs for different spin-orbit manifolds show different preferences in forward or backward scattering directions at the same collision energies.This study reveals that,even though the title reaction proceeds via the long-lived complex mechanism,the spin-orbit coupling effects in the product channels play an important role in the reaction process.
基金supported by the National Key Research and Development Program of China(No.2022YFA1602502)the National Natural Science Foundation of China(No.12127804).
文摘The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O_(2)^(2+),O_(2)^(2+)O^(+),O^(2+),and their total)and two Coulomb explosion channels(O^(+)+O^(+)and O^(2+)+O^(+))are obtained by putting the data of O^(2+)on the scale of Ar+from O_(2)and Ar gases mixed with a fixed relative flow ratio of 1:1.The experimental errors are assessed by taking uncertainties of various factors into account.The present absolute cross sections are well consistent with the previous data in the overlapped energy range below 1000 eV.
基金supported by the National key R&D program(Nos.2022YFA1602404 and 2023YFA1606901)the National Natural Science Foundation of China(Nos.12375123 and 12388102)the Natural Science Foundation of Henan Province(No.242300422048).
文摘To overcome the difficulty and high cost of some specific isotopic targets,a substitution method was proposed to measure the cross section of the(γ,n)reactions.Considering that the natural copper element(^(nat)Cu)only has^(63)Cu and^(65)Cu isotopes,the^(65)Cu(γ,n)^(64)Cu reaction was taken as an example to test the substitution method.Using quasi-monoenergeticγbeams provided by the Shanghai Laser Electron Gamma Source(SLEGS)of the Shanghai Synchrotron Radiation Facility(SSRF),^(nat)Cu(γ,n)was measured from E_(γ)=11.09 MeV to 17.87 MeV.Furthermore,based on the^(63)Cu(γ,n)reaction measured using the same experimental setup at SLEGS,^(65)Cu(γ,n)^(64)Cu was extracted using the substitution method.The abundance variation of natural copper,showing a significant influence on the cross section,was also investigated.The results were compared to the existing experimental data measured by bremsstrahlung and positron annihilation in-flight sources,and the TALYS 2.0 predictions.Theγstrength function(γSF)of^(65)Cu was obtained from the^(65)Cu(γ,n)data,and the reaction cross section of^(64)Cu(n,γ)was further calculated.
基金supported in part by the National Natural Science Foundation of China(Nos.12105327 and 11775108)the Hunan Provincial Innovation Foundation For Postgraduate(No.QL20220210)the Advanced Energy Science and Technology Guangdong Laboratory.
文摘Inelastic collisions are the dominant cause of energy loss in radiotherapy.In the energy range around the Bragg peak,single ionization(SI)and single-electron capture(SC)are the primary inelastic collisions that lead to energy loss.This study employs the classical trajectory Monte Carlo method to study the SI and SC processes of H_(2)O molecules using He^(2+) and C^(6+) projectiles in the energy range of 10 keV/u to 10 MeV/u.The total cross sections,single differential cross sections,impact parameter dependence of SI and SC,and fragmentation cross sections were investigated.Results illustrate that the cross section for SI is the highest when the projectile energy is close to the Bragg peak energy.When the projectile energy is below the Bragg peak energy,the ionized electrons in the forward direction dominate,and the removal of electrons can be associated with large impact parameters.As the projectile energy increases,the emission angle of the electrons gradually transitions from small angles(60°~120°)to large angles(60°~120°),and the removal of electrons is associated with small impact parameters.The energy distributions of the ionized electron are similar when the projectile energy is equal to,below or above the Bragg peak energy.The fragmentation cross sections after SI and SC in the energy range around the Bragg peak were also estimated.
基金supported by the Ministry of Education Chunhui Program Collaborative Scientific Research Projects(Grant No.:HZKY20220286)Henan Province Foreign Experts Introduction Program(Grant No.:HNGD2022021)+1 种基金Natural Science Foundation of Henan Province(Grant No.:23230042151)the Foundation of the National Key Program of Research and Development of China(Grant No.:2016YFC0900803)。
文摘Rapid population aging has led to an increased focus on age-related conditions such as sarcopenia.causing loss of muscle mass and strength^([1,2]). Sarcopenia is associated with adverse outcomes,including falls, functional decline, frailty, and mortality, which can lower the quality of life and shorten lifespan^([1,2]).
基金supported by the National Natural Science Foundation of China(82102018,62333002,T2425027,and 82327809)Data collection and sharing for this project were supported by the National Natural Science Foundation of China(61633018,81571062,81471120,and 81901101)+30 种基金Data collection and sharing for this project were funded by the ADNI(National Institutes of Health Grant U01 AG024904)the Department of Defense ADNI(award number W81XWH-12-2-0012).The ADNI is funded by the National Institute on Aging,the National Institute of Biomedical Imaging and Bioengineering,and through generous contributions from the following:AbbVie,Alzheimer’s AssociationAlzheimer’s Drug Discovery FoundationAraclon BiotechBioClinica,Inc.BiogenBristol-Myers Squibb Co.CereSpir,Inc.CogstateEisai Inc.Elan Pharmaceuticals,Inc.Eli Lilly and Co.EuroImmunF.Hoffmann-La Roche Ltd and its affiliated company Genentech,Inc.FujirebioG.E.HealthcareIXICO Ltd.Janssen Alzheimer Immunotherapy Research&Development,LLC.Johnson&Johnson Pharmaceutical Research&Development LLC.LumosityLundbeckMerck&Co.,Inc.Meso Scale Diagnostics,LLC.NeuroRx ResearchNeurotrack TechnologiesNovartis Pharmaceuticals Corp.Pfizer Inc.Piramal ImagingServierTakeda Pharmaceutical Co.and Transition Therapeutics.The Canadian Institutes of Health Research provides funds to support ADNI clinical sites in Canada.Private sector contributions are facilitated by the Foundation for the National Institutes of Health(www.fnih.org).The grantee organization was the Northern California Institute for Research and Education,and the study was coordinated by the Alzheimer’s Therapeutic Research Institute at the University of Southern California.ADNI data are disseminated by the Laboratory for Neuro Imaging at the University of Southern California.
文摘Dear Editor,Growing clinical evidence shows that brain disorders are heterogeneous in phenotype,genetics,and neuropathology[1].Diagnosis and treatment tend to be affected by symptom presentation and the heterogeneity of pathology,potentially hindering clinical trials in the development of medical treatment.Brain-based subtyping studies utilize magnetic resonance imaging(MRI)and data-driven methods to discover the subtypes of diseases,providing a new perspective on disease heterogeneity.
文摘Dear Editor,I am writing in response to the article“Assessment of nurses’workplace silence behavior motives:A cross-sectional study”by Alhojairi et al.published in the September 2024 issue of the International Journal of Nursing Sciences[1].This is a letter written by a nurse with 10 years of clinical work experience and a personal interest in team dynamics.I appreciate the authors'recommendations on mitigating workplace silence among nurses to enhance clinical work development,and I believe their proposals could be expanded further.
文摘BACKGROUND Transition is a critical period for adolescents as they begin to assume responsibility for their own health.Similarly,the shift from pediatric to adult healthcare represents a vulnerable phase,marked by unique challenges in adolescent health care.Despite its importance,only a few studies have explored healthcare transition among adolescents in Uganda.AIM To identify factors associated with the transition to adult human immunodeficiency virus(HIV)-centered care among adolescents attending HIV/AIDS clinics in Uganda.METHODS A cross-sectional mixed-methods study was conducted among 265 adolescents,randomly selected from three antiretroviral therapy(ART)clinics,using a structured questionnaire.Focus group discussions and key informant interviews were conducted.Individuals aged 10-20 years who were actively enrolled in the ART program between January 4,2022 and January 30,2023 were recruited.The primary outcome of interest was the transition to adult care.Bivariate and multivariate analyses were performed for quantitative data,while content analysis was used to analyze qualitative data.RESULTS The prevalence of transition to adult care was 40.6%.Most participants were male(53.6%)and fell within the 13-15 age group(35.6%).Multivariate logistic regression analysis identified several factors significantly associated with transition to adult care:Age group 10-12 years[prevalence ratio(PR)=2.525,95%CI:2.121-2.944,P=0.002],Age group 13-15 years(PR=1.900,95%CI:1.196-3.416,P=0.001),successful viral load suppression(PR=1.534,95%CI:1.173-1.648,P=0.016),disclosure of HIV status to relatives(PR=5.001,95%CI:3.411-3.611,P=0.000),being prepared for transitioning(PR=5.417,95%CI:3.468-7.135,P=0.041)and having skilled pediatric caregivers(PR=3.724,95%CI:2.084-4.105,P=0.005).CONCLUSION Transition to adult care among adolescents was low.Improving transition outcomes may require strengthening individual support within the family context and integrating transition-focused care into existing specialized clinical settings to enhance the delivery of adolescent-friendly services.
文摘Arterial stiffness is considered an important indicator reflecting age-related changes in the vascular wall[1]and the risk of developing comorbidities,[2]primarily cardiovascular diseases.[3]Cardiovascular diseases remain the leading cause of death worldwide.Many factors influence the rate of arterial aging.Research results have confirmed that arterial wall stiffness increases with an increasing number of risk factors,[4]as each of them acts independently through various mechanisms,adversely affecting the structure and function of the cardiovascular system.
基金supported by the National Natural Science Foundation of China(Nos.12465024,12365018,U2032146)Inner Mongolia National Science Foundation(Nos.2024ZD23,2024FX30,2023MS01005)+1 种基金Program for Innovative Research Team in Universities of Inner Mongolia Autonomous Region(NMGIRT2217)Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT23109)。
文摘The neutron capture cross section for^(165)Ho was measured at the backstreaming white neutron beam line(Back-n)of the China Spallation Neutron Source(CSNS)using total energy detection systems,composed of a set of four C_(6)D_(6)scintillator detectors coupled with pulse height weighting techniques.The resonance parameters were extracted using the multilevel multichannel R-matrix code SAMMY to fit the measured capture yields of the^(165)Ho(n,γ)reaction in the neutron energy range below100 eV.Subsequently,the resonance region’s capture cross sections were reconstructed based on the obtained parameters.Furthermore,the unresolved resonance average cross section of the^(165)Ho(n,γ)reaction was determined relative to that of the standard sample^(197)Au within the neutron energy range of 2 keV to 1 MeV.The experimental data were compared with the recommended nuclear data from the ENDF/B-VIII.0 library,as well as with results of calculations performed using the TALYS-1.9 code.The comparison revealed agreement between the measured^(165)Ho(n,γ)cross sections and these data.The present results are crucial for evaluating the^(165)Ho neutron capture cross section and thus enhance the quality of evaluated nuclear data libraries.They provide valuable guidance for nuclear theoretical models and nuclear astrophysical studies.
基金supported by the National Natural Science Foundation of China(No.12075135)the National Natural Science Foundation of China(No.12375127)。
文摘The radioisotope actinium-225(^(225)Ac)has been successfully used for targeted alpha therapy in preclinical and clinical applications because of its excellent nuclear characteristics.Medium-and high-energy proton-spallation reactions on thorium are the most important methods for producing^(225)Ac.This study examines the possibility of producing^(225)Ac by irradiating thorium oxide with medium-energy protons.Thorium-oxide sheets were irradiated with 40-,50-,60-,70-,and 80-Me V protons on the Associated Proton-beam Experiment Platform(APEP)of the China Spallation Neutron Source(CSNS).The cross sections for the formation of^(225)Ac were measured using the activation method and offline gamma-ray spectrometric technique.The experimental results were compared with the existing data from EXFOR as well as the theoretical data from the TALYS-based evaluated nuclear-data library.Based on the experimental cross section and theoretical calculations,the production yield of^(225)Ac in the irradiated thorium targets was examined.The results showed that APEP can produce sufficient quantities of^(225)Ac for purification and clinical therapy.This work is the first measurement of proton-induced nuclearreaction cross sections at the CSNS APEP.
基金supported by the Key Research and DevelopmentPlan in Shanxi Province of China(No.201803D421045)the Natural Science Foundation of Shanxi Province(No.2021-0302-123104)。
文摘This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are obtained.Pore structures are segmented by the U-shaped network(U-Net)neural network integrated with the Canny edge detection operator,ensuring accurate pore delineation and edge extraction.The trained U-Net achieves 98.55%accuracy.The 2D data are superimposed and processed into 3D point clouds,enabling reconstruction of the pore structure and aluminum skeleton.Analysis of pore 01 shows the cross-sectional area initially increases,and then decreases with milling depth,with a uniform point distribution of 40 per layer.The reconstructed model exhibits a porosity of 77.5%,with section overlap rates between the 2D pore segmentation and the reconstructed model exceeding 96%,confirming high fidelity.Equivalent sphere diameters decrease with size,averaging 1.95 mm.Compression simulations reveal that the stress-strain curve of the 3D reconstruction model of aluminum foam exhibits fluctuations,and the stresses in the reconstruction model concentrate on thin cell walls,leading to localized deformations.This method accurately restores the aluminum foam’s complex internal structure,improving reconstruction preci-sion and simulation reliability.The approach offers a cost-efficient,high-precision technique for optimizing material performance in engineering applications.
基金support from National Natural Science Foundation of China(Grant No.52474142)The National Science Fund for Distinguished Young Scholars(No.51925402),Chinathe China Postdoctoral Science Foundation(Grant No.2021M702049).
文摘Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical analysis of roof structures and adopts a multivariate nonlinear analysis approach to explore the synergistic load-bearing effects within the'coal pillar-support-backfill body'system during the fill and re-mining processes above these roadways.The findings demonstrate that backfill mining significantly reduces stress concentrations in coal pillars and reduces excessive bending moments in roofs near abandoned roadways.The roof deflection equation incorporates three critical factors affecting stability during backfill mining:the width of the coal pillar(L_(3)),the working resistance of the support(q_(z)),and the elastic foundation coefficient of the backfill material(kcÞ.Under single-factor conditions,the impact sequence on roof stability in the coal pillar zone is·k_(c)>L_(3)>q_(z).Further,multivariate nonlinear analysis reveals the interactions within the'coal-support-backfill'structure,indicating that in terms of roof control,the interaction terms are ordered as L_(3)·k_(c)>q_(z)·k_(c)>L_(3)q_(z).Therefore,priority should be given to adjusting the coal pillar width and backfill strength,followed by modifications to the support resistance and backfill strength during the recovery of abandoned roadways.An improved understanding of these interactions will help optimize strategies for the recovery of residual coal through abandoned roadways,thereby enhancing the stability and safety of mining operations under complex geological conditions.
基金supported by the National Natural Science Foundation of China(32371874,32401569)supported by Beijing Natural Science Foundation(6244053)。
文摘Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods often overlook the multi-scale nature of bird targets,limiting their ability to capture rich contextual information across different scales.To address this,we propose a cross-dimensional attention network(CDA-Net)for bird detection that integrates spatial and channel information to improve species recognition.The proposed CDA-Net partitions feature maps into multiple channel wise sub-features.Spatial and channel attention are applied to each subfeature,and the resulting features are fused using the Hadamard product.The fused features are then forwarded to the detection head to generate the final detection results.This approach effectively captures and integrates information across spatial and channel dimensions.Experiments on our self-constructed Nanhai Wetland Waterbird Dataset and the public CUB-200-2011 dataset yield precision scores of 91.32%and 81.99%,respectively,outperforming existing methods.Our approach effectively handles scale variation in bird detection and provides a valuable tool for advancing automated wetland waterbird monitoring.
文摘Let M be a compact n-manifold of positive sectional curvature.We will review classical results on the fundamental group of M,a motivation on the c(n)-cyclic conjecture that the fundamental group of M contains a cyclic subgroup of index bounded above by c(n),a constant depending only on n,and we will survey partial results(up to date)on the c(n)-cyclic conjecture.
基金supported by the STI2030-Major Projects(2021ZD0200600)the National Natural Science Foundation of China(81971269).
文摘In recent years,the field of neuroimmunology has witnessed a profound paradigm shift.Research has expanded beyond the traditional focus on the central nervous system to unravel the dynamic interplay between peripheral immunity and neural networks.Cutting-edge methodologies have unmasked a tripartite communication axis enabling peripheral immune signals to mediate the CNS:(1)neural communication via vagal afferents,(2)humoral signaling through circumventricular organ cytokine diffusion,and(3)cellular interactions involving bone marrow-derived macrophages[1].
