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Transport in Astrophysics: VI. Ultra-High Energy Cosmic Rays
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2024年第1期65-84,共20页
Two new solutions of the homogeneous diffusion equation in 1D are derived in the presence of losses and a trigonometric profile for a profile of density. A simulation for the ankle in the energy distribution of cosmic... Two new solutions of the homogeneous diffusion equation in 1D are derived in the presence of losses and a trigonometric profile for a profile of density. A simulation for the ankle in the energy distribution of cosmic rays (CRs) is provided in the framework of the fine tuning of the involved parameters. A theoretical image for the overall diffusion of CRs in galactic coordinates is provided. 展开更多
关键词 Cosmic rays Particle Diffusion Random Walks
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交互式数字叙事:加拿大Writing New Body Worlds阅读治疗新探索
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作者 牟晓青 于志涛 《图书馆论坛》 CSSCI 北大核心 2024年第4期222-230,F0003,共10页
文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性... 文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性健康干预。基于数据与计算的精准化阅读治疗是数字人文视角下的新变革,更具推广应用价值;以在线阅读平台建设为依托,推进实施平台化的阅读和治疗应成为未来发展方向之一;基于阅读形态与体验因技术赋能而改变的现状,图书馆应发挥引领作用,积极收集、创建或协助创建数字故事,推进阅读推广、服务与治疗的融合性发展,成为社区建设促进者、历史欣赏者和社区参与倡导者,也使阅读借助交互式数字叙事这一新载体,更好地发挥变革的力量,促进健康与幸福。 展开更多
关键词 交互式数字叙事 阅读治疗 Writing New body Worlds 加拿大
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基于3D Body软件的混合模式在放射肿瘤学教学中的应用
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作者 马岚 王亚利 +5 位作者 杨彭涛 李丹 张扬 包兴 李毅 潘纪元 《医学教育研究与实践》 2024年第6期792-797,804,共7页
目的分析基于3D Body软件的线上线下混合式模式应用于放射肿瘤学教学中的效果。方法选取两个阶段参与放射肿瘤学教学的实习生,其中2022年1月—12月的32名实习生(对照组)采用传统带教模式;2023年1月—12月的32名实习生(观察组)采用基于3D... 目的分析基于3D Body软件的线上线下混合式模式应用于放射肿瘤学教学中的效果。方法选取两个阶段参与放射肿瘤学教学的实习生,其中2022年1月—12月的32名实习生(对照组)采用传统带教模式;2023年1月—12月的32名实习生(观察组)采用基于3D Body软件的线上线下混合式教学模式,评估两组放射肿瘤学教学效果。结果观察组理论考核、实践操作考核、平时成绩均高于对照组,差异有统计学意义(P<0.05);观察组专业技术(包括靶区勾画、制定计划、计划评估,计划验证)能力评分均高于对照组,差异有统计学意义(P<0.05);观察组评判性思维能力高于对照组,差异有统计学意义(P<0.05);观察组实习生的自我能力评价分值高于对照组,差异有统计学意义(P<0.05);观察组实习生对教学模式满意度评价分值高于对照组,差异有统计学意义(P<0.05)。结论放射肿瘤学教学实践中,相比传统带教模式,基于3D Body软件的线上线下混合式教学模式具有明显改善教学效果、提高实习生专业技术能力与评价满意度的作用。 展开更多
关键词 3D body软件 线上线下混合式教学模式 放射肿瘤学 临床教学
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3D body解剖软件联合PACS系统在骨科临床实践教学中的应用
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作者 王建乐 徐文斌 +3 位作者 马彦 马建军 范顺武 沈舒滢 《全科医学临床与教育》 2024年第6期530-532,共3页
目的探讨3D body解剖软件结合医学影像存档与通信系统(PACS)在骨科临床实践教学中的应用效果。方法选择2023年1月至2023年12月在浙江大学医学院附属邵逸夫医院骨科轮转的60名实习生,按照随机数字表法分成实验组和对照组,每组30名。对照... 目的探讨3D body解剖软件结合医学影像存档与通信系统(PACS)在骨科临床实践教学中的应用效果。方法选择2023年1月至2023年12月在浙江大学医学院附属邵逸夫医院骨科轮转的60名实习生,按照随机数字表法分成实验组和对照组,每组30名。对照组采用传统线上结合线下的混合式教学方法,实验组采用3D body解剖软件联合PACS系统带教模式。在实习期结束时,对两组实习生进行闭卷理论考试与临床实践操作考核,并采用问卷调查方式评估实习生对课程的满意度。结果实验组实习生的理论考试与临床实践操作成绩均高于对照组,差异均有统计学意义(t分别=6.59、4.22,P均<0.05)。实验组实习生在学习兴趣、教学难度、专业能力以及医患沟通能力提升方面的满意度均高于对照组,差异均有统计学意义(χ^(2)分别=9.93、3.77、6.94、8.52,P均<0.05)。结论3D body解剖软件联合PACS系统带教模式运用到骨科实习生的临床教学中,能帮助实习生提高学习兴趣以及医患沟通能力,加强对骨科知识的掌握,降低知识的理解难度,对于提升临床医学教学质量具有重要意义。 展开更多
关键词 3D body解剖软件 PACS系统 骨科实践 临床教学
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Soft,body conformable electronics for thermoregulation enabled by kirigami 被引量:1
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作者 Lung Chow Guangyao Zhao +17 位作者 Pengcheng Wu Xingcan Huang Jiyu Li Jian Li Wanying Wang Guihuan Guo Zhiyuan Li Jiachen Wang Jingkun Zhou Yawen Yang Yuyu Gao Binbin Zhang Qiang Zhang Dengfeng Li Ya Huang Kuanming Yao Jian Lu Xinge Yu 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期453-462,共10页
The application of thermoelectric devices(TEDs)for personalized thermoregulation is attractive for saving energy while balancing the quality of life.TEDs that directly attach to human skin remarkably minimized the ene... The application of thermoelectric devices(TEDs)for personalized thermoregulation is attractive for saving energy while balancing the quality of life.TEDs that directly attach to human skin remarkably minimized the energy wasted for cooling the entire environment.However,facing the extreme dynamic geometry change and strain of human skin,conventional TEDs cannot align with the contour of our bodies for the best thermoregulation effect.Hence,we designed a kirigami-based wearable TED with excellent water vapor permeability,flexibility,and conformability.Numerical analysis and experimental results reveal that our product can withstand various types of large mechanical deformation without circuit rupture.The stated outcome and proposed facile approach not only reinforce the development of wearable TEDs but also offer an innovative opportunity for different electronics that require high conformability. 展开更多
关键词 THERMOREGULATION THERMOELECTRIC Kirigami body conformable WEARABLE
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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults 被引量:1
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao Lin Yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS body fat distribution Physical activity Sitting time
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Association between body mass index and body fat measured by dual-energy X-ray absorptiometry (DXA) in China: a systematic review and meta-analysis
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作者 Xiaomin Sun Na Yan +3 位作者 Wen Peng Tuan T Nguyen Lu Ma Youfa Wang 《Global Health Journal》 2023年第2期61-69,共9页
Objective:We examined the association between body mass index(BMI)and body fat percentage(BF%)measured by dual-energy X-ray absorptiometry(DXA)among adults and children in China.Methods:We searched four databases-PubM... Objective:We examined the association between body mass index(BMI)and body fat percentage(BF%)measured by dual-energy X-ray absorptiometry(DXA)among adults and children in China.Methods:We searched four databases-PubMed,China National Knowledge Infrastructure,Wanfang,and Vip for studies published in the past 22 years.Meta-analysis was conducted using random-or fixed-effect models.Results:In total of 21 studies met inclusion criteria and were included in review,and 17 ot them in meta-analysis.They were conducted across China.Their sample size ranged from 62 to 5726,and participants'age ranged from 6-80 years.Meta-analysis revealed strong associations between BMI and BF% measured by DXA in adults(pooled r=0.71,95% CI:0.66 to 0.74)and children(pooled r=0.60,95% CI:0.52 to 0.68).The association was stronger in Northern China than in East China in children(β=-0.40,95%CI:-0.65 to-0.14)and in Central China in adults(β=-0.25;95% CI:-0.51 to-0.01).Urban children's BMI was strongly associated with BF%than rural(β=0.19;95%CI:0.04 to 0.35),whereas it was stronger in adults living in rural than in urban(β=-0.35;95% CI:-0.66 to-0.05).Conclusions:BMI was strongly associated with BF%measured by DXA,and the association in children and adults in China varied by residence and region. 展开更多
关键词 body mass index Dual-energy x-ray absorptiometry body adiposity Children ADULTS China
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Stereotactic body radiotherapy in pancreatic adenocarcinoma 被引量:1
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作者 Carolina de la Pinta 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第1期14-19,共6页
Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding tissue.This review aimed at the SBRT application in the treatment of ... Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding tissue.This review aimed at the SBRT application in the treatment of pancreatic cancer.Data sources:We retrieved articles published in MEDLINE/PubMed from January 2017 to December 2022.Keywords used in the search included:“pancreatic adenocarcinoma”OR“pancreatic cancer”AND“stereotactic ablative radiotherapy(SABR)”OR“stereotactic body radiotherapy(SBRT)”OR“chemoradiotherapy(CRT)”.English language articles with information on technical characteristics,doses and fractionation,indications,recurrence patterns,local control and toxicities of SBRT in pancreatic tumors were included.All articles were assessed for validity and relevant content.Results:Optimal doses and fractionation have not yet been defined.However,SBRT could be the standard treatment in patients with pancreatic adenocarcinoma in addition to CRT.Furthermore,the combination of SBRT with chemotherapy may have additive or synergic effect on pancreatic adenocarcinoma.Conclusions:SBRT is an effective modality for patients with pancreatic cancer,supported by clinical practice guidelines as it has demonstrated good tolerance and good disease control.SBRT opens a possibility of improving outcomes for these patients,both in neoadjuvant treatment and with radical intent. 展开更多
关键词 CHEMORADIOTHERAPY Pancreatic adenocarcinoma RADIOTHERAPY Stereotactic body radiotherapy Stereotactic ablative radiotherapy
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Body composition and metabolic syndrome in patients with type 1 diabetes 被引量:2
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作者 Qiong Zeng Xiao-Jing Chen +3 位作者 Yi-Ting He Ze-Ming Ma Yi-Xi Wu Kun Lin 《World Journal of Diabetes》 SCIE 2024年第1期81-91,共11页
BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relatio... BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relationship between body composition,metabolic syndrome and insulin resistance in T1DM to guide clinical treatment and intervention.AIM To assess body composition(BC)in T1DM patients and evaluate the relationship between BC,metabolic syndrome(MS),and insulin resistance in these indi-viduals.METHODS A total of 101 subjects with T1DM,aged 10 years or older,and with a disease duration of over 1 year were included.Bioelectrical impedance analysis using the Tsinghua-Tongfang BC Analyzer BCA-1B was employed to measure various BC parameters.Clinical and laboratory data were collected,and insulin resistance was calculated using the estimated glucose disposal rate(eGDR).RESULTS MS was diagnosed in 16/101 patients(15.84%),overweight in 16/101 patients(15.84%),obesity in 4/101(3.96%),hypertension in 34/101(33.66%%)and dyslip-idemia in 16/101 patients(15.84%).Visceral fat index(VFI)and trunk fat mass were significantly and negatively correlated with eGDR(both P<0.001).Female patients exhibited higher body fat percentage and visceral fat ratio compared to male patients.Binary logistic regression analysis revealed that significant factors for MS included eGDR[P=0.017,odds ratio(OR)=0.109],VFI(P=0.030,OR=3.529),and a family history of diabetes(P=0.004,OR=0.228).Significant factors for hypertension included eGDR(P<0.001,OR=0.488)and skeletal muscle mass(P=0.003,OR=1.111).Significant factors for dyslipidemia included trunk fat mass(P=0.033,OR=1.202)and eGDR(P=0.037,OR=0.708).CONCLUSION Visceral fat was found to be a superior predictor of MS compared to conventional measures such as body mass index and waist-to-hip ratio in Chinese individuals with T1DM.BC analysis,specifically identifying visceral fat(trunk fat),may play an important role in identifying the increased risk of MS in non-obese patients with T1DM. 展开更多
关键词 body composition Metabolic syndrome Insulin resistance Visceral fat Estimated glucose disposal rate
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Injection Spectra of Different Species of Cosmic Rays from AMS-02, ACE-CRIS and Voyager-1
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作者 Xu Pan Qiang Yuan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第11期7-13,共7页
Precise measurements of energy spectra of different cosmic ray(CR) species have been obtained in recent years, by particularly the AMS-02 experiment on the International Space Station. It has been shown that apparent ... Precise measurements of energy spectra of different cosmic ray(CR) species have been obtained in recent years, by particularly the AMS-02 experiment on the International Space Station. It has been shown that apparent differences exist in different groups of the primary CRs. However, it is not straightforward to conclude that the source spectra of different particle groups are different since they will experience different propagation processes(e.g., energy losses and fragmentations) either. In this work, we study the injection spectra of different nuclear species using the measurements from Voyager-1 outside the solar system, and ACR-CRIS and AMS-02 on the top of atmosphere, in a physical framework of CR transportation. Two types of injection spectra are assumed, the broken power-law(BPL) form and the non-parametric spline interpolation form. The non-parametric form fits the data better than the BPL form, implying that potential structures beyond the constrained spectral shape of BPL may exist. For different nuclei the injection spectra are overall similar in shape but do show some differences among each other. For the non-parametric spectral form, the helium injection spectrum is the softest at low energies and the hardest at high energies. For both spectral shapes, the low-energy injection spectrum of neon is the hardest among all these species, and the carbon and oxygen spectra have more prominent bumps in 1–10 GV in the R2 d N dRpresentation.Such differences suggest the existence of differences in the sources or acceleration processes of various nuclei of CRs. 展开更多
关键词 (ISM:)cosmic rays acceleration of particles astroparticle physics
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X-ray在鱼体组织及微量元素检测中的应用
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作者 宋一帆 张胜茂 +4 位作者 张衡 唐峰华 张寒野 石永闯 崔雪森 《应用光学》 CAS 北大核心 2024年第1期166-176,共11页
鱼类硬质组织物,特别是骨骼支持鱼体和保护其体内器官的组织,对其进行特征检测分析是研究鱼类游泳运动、鱼类解剖、鱼体建模等的数据基础。随着X-ray技术的发展和国产设备的广泛应用,其仪器设备成本明显降低,使得X-ray在渔业研究与自动... 鱼类硬质组织物,特别是骨骼支持鱼体和保护其体内器官的组织,对其进行特征检测分析是研究鱼类游泳运动、鱼类解剖、鱼体建模等的数据基础。随着X-ray技术的发展和国产设备的广泛应用,其仪器设备成本明显降低,使得X-ray在渔业研究与自动化生产中的应用成为可能。首先介绍了X-ray技术的基本原理与其在鱼体组织检测中的应用,X-ray技术在鱼体组织及微量元素检测中的应用主要分为鱼类组织器官的无损检测和鱼体微量元素检测两部分,其中分别介绍了包括照相法、数字成像法、衍射技术和吸收光谱法等X-ray技术;然后综述其在鱼体组织器官建模、鱼骨检测、鱼类化石研究、鱼耳石分析和鱼体微量元素检测方面的应用,总结了Xray在渔业领域应用中存在的问题;最后对X-ray的渔业应用方向进行展望。 展开更多
关键词 X-ray 鱼体骨骼 鱼类耳石 鱼体建模 鱼体微量元素
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Curved Spine:The Shape of Spine in Taoist Body Diagrams and Its Influence on Medical Body Diagrams 被引量:1
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作者 ZHANG Xinyue ZHANG Shujian 《Chinese Medicine and Culture》 2024年第3期251-261,共11页
From the early Taoist diagrams of the human body to the end of the Qing dynasty and the beginning of the Republic of China,Taoists exaggerated and deformed the human spine in a shape-shifting manner.It is likely that ... From the early Taoist diagrams of the human body to the end of the Qing dynasty and the beginning of the Republic of China,Taoists exaggerated and deformed the human spine in a shape-shifting manner.It is likely that medical practitioners were influenced by this style of representation,and there are also numerous diagrams of the human body with the curved spine in the lateral-view diagrams of viscera and Ming Tang Tu(明堂图Acupuncture and Moxibustion Chart),which constantly show the human torso in an elliptical“egg shape”.No later than the Ming dynasty,medical practitioners began to depict the actual physiological spinal curve of the human body.By the Qing dynasty,the depiction of the spinal curve in medical diagrams of the human figure showed a tendency to part ways with the Taoist freehand style of the previous generation.Although the representation of the curve of the spine was very crude,later medical images of the human body at least gradually straightened the spine and no longer depicted it in a shape-shifting manner.However,the curved spine in Taoist diagrams of the human body continued to exist,and the presentation of the curved spine never changed.This way of depicting its appearance,which is very different from reality,is shaped by Taoism's special way of perceiving and viewing the body,and may also contain another form of truth. 展开更多
关键词 SPINE Diagrams of human body Taoists Traditional Chinese medical practitioners
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α-Synuclein pathology from the body to the brain:so many seeds so close to the central soil 被引量:1
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作者 Yunying Yang Zhentao Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1463-1472,共10页
α-Synuclein is a protein that mainly exists in the presynaptic terminals.Abnormal folding and accumulation of α-synuclein are found in several neurodegenerative diseases,including Parkinson’s disease.Aggregated and... α-Synuclein is a protein that mainly exists in the presynaptic terminals.Abnormal folding and accumulation of α-synuclein are found in several neurodegenerative diseases,including Parkinson’s disease.Aggregated and highly phospho rylated a-synuclein constitutes the main component of Lewy bodies in the brain,the pathological hallmark of Parkinson s disease.For decades,much attention has been focused on the accumulation of α-synuclein in the brain parenchyma rather than considering Parkinson s disease as a systemic disease.Recent evidence demonstrates that,at least in some patients,the initial α-synuclein pathology originates in the peripheral organs and spreads to the brain.Injection of α-synuclein preformed fibrils into the gastrointestinal tra ct trigge rs the gutto-brain propagation of α-synuclein pathology.However,whether α-synuclein pathology can occur spontaneously in peripheral organs independent of exogenous α-synuclein preformed fibrils or pathological α-synuclein leakage from the central nervous system remains under investigation.In this review,we aimed to summarize the role of peripheral α-synuclein pathology in the pathogenesis of Parkinson’s disease.We also discuss the pathways by which α-synuclein pathology spreads from the body to the brain. 展开更多
关键词 aggregation autonomic nervous system barrier receptors body fluid circulation in situ generation Parkinson’s disease PHOSPHORYLATION propagation SYNUCLEINOPATHIES Α-SYNUCLEIN α-synuclein fibrils
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3D Body解剖软件结合CBL教学法在骨科实习生临床带教中的应用
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作者 张树文 地力木拉提·艾克热木 王浩 《教育进展》 2024年第6期1489-1493,共5页
目的:探讨3D body解剖软件结合CBL教学法在骨科实习生临床带教中的应用效果。方法:随机选取2022年1月~2023年12月在我科室实习的36名骨科实习生为研究对象,随机分为观察组和对照组,对照组采用CBL教学模式,观察组在对照组的教学模式上运... 目的:探讨3D body解剖软件结合CBL教学法在骨科实习生临床带教中的应用效果。方法:随机选取2022年1月~2023年12月在我科室实习的36名骨科实习生为研究对象,随机分为观察组和对照组,对照组采用CBL教学模式,观察组在对照组的教学模式上运用3D body解剖软件。教学结束后,比较两组学生的理论知识考试成绩,PPT汇报成绩以及教学满意度。结果:观察组学生理论知识考核成绩、PPT汇报成绩、教学满意度明显高于对照组,差异具有显著性(P < 0.05)。结论:3D body解剖软件结合CBL教学法应用于骨科实习生临床带教,可以有效提高学生成绩,调动学生积极性及自主学习能力,提升教学满意度。 展开更多
关键词 3D body解剖软件 CBL教学法 实习生 骨科
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Fast X-ray imaging beamline at SSRF
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作者 Ke Li Hong-Lan Xie +5 位作者 Ya-Nan Fu Fei-Xiang Wang Guo-Hao Du Jian-Feng ji Biao Deng Ti-Qiao Xiao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期68-81,共14页
The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and... The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and ms.This beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic loads.In addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive engines.The light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid nitrogen.This CPMU can generate X-ray photons within an energy range of 8.7-30 keV.The beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam path.Four X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative micro-CT.Furthermore,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray chamber.Following the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023. 展开更多
关键词 Multiple time-scale X ray imaging Single-pulse X ray imaging Dynamic 2D imaging Dynamic micro-CT
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THE RELATIONSHIP BETWEEN RADIATION DOSE AND CHROMOSOME ABERRATIONS AND MICRONUCLEI IN RABBITS EXPOSED TO FRACTIONATED WHOLE-BODY ^(60)Co GAMMA RAYS
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《癌变.畸变.突变》 CAS CSCD 1991年第S1期4-4,共1页
The frequencies of chromosome aberrationsand micronuclei showed an increase withdoses after irradiation of rabbitsexposed to fractionated or single whole-body <sup>60</sup>Co gamma rays.At most dose points,
关键词 fractionated GAMMA chromosome irradiation CO GAMMA rays GAMMA ABERRATION body quadratic doses
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0.05 T MRI for whole body
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作者 Ya Wang Shihao Tang +3 位作者 Jinyu Yang Bowen Peng Yajie Xu Xiaodong Yang 《Magnetic Resonance Letters》 2024年第3期60-61,共2页
Recently,a study on a 0.05 T,low-cost,low-power,and computing-driven shielding-free ultra-low-field(ULF)magnetic resonance imaging(MRI)scannerwas published.This work enhances the image quality of MRI and reduces the s... Recently,a study on a 0.05 T,low-cost,low-power,and computing-driven shielding-free ultra-low-field(ULF)magnetic resonance imaging(MRI)scannerwas published.This work enhances the image quality of MRI and reduces the scanning time based on deep learning methods,which is of great significance to enhancing the popularization and availability of MRI[1](https://www.science.org/doi/abs/10.1126/science.adm7168). 展开更多
关键词 SCANNER body SHIELDING
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Cosmic Ray-driven Bioenergetics for Life in Molecular Clouds
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作者 FENG Lei 《天文学报》 CAS CSCD 北大核心 2024年第6期26-31,共6页
According to models such as panspermia or the Nebula-Relay hypothesis,the ancestors of life on Earth once lived in molecular clouds.Then what are the energy source and bioenergetics for such lifeforms?A new bioenerget... According to models such as panspermia or the Nebula-Relay hypothesis,the ancestors of life on Earth once lived in molecular clouds.Then what are the energy source and bioenergetics for such lifeforms?A new bioenergetic mechanism powered by cosmic ray ionization of hydrogen molecules is proposed and its relation with the origin of chemiosmosis is also discussed in this paper.Based on this mechanism,the Last Universal Common Ancestor may be a type of lifeform that utilizes hydrogen molecules as donors of electron transport chains. 展开更多
关键词 ASTROBIOLOGY ASTROCHEMISTRY interstellar medium(ISM) NEBULAE cosmic ray
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Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study
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作者 Huijuan Ruan Yajie Zhang +6 位作者 Qingya Tang Xuan Zhao Xuelin Zhao Yi Xiang Wei Geng Yi Feng Wei Cai 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期254-264,共11页
Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term foll... Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers. 展开更多
关键词 Human milk Milk composition body weight body mass index(BMI) Weight gain Postpartum weight retention
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Advances and Challenges of Exosome Metabolomics in Body Fluids
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作者 CAO Yiqing HOU Jingxin +1 位作者 LIU Jianye LI Yan 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期1-15,共15页
Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and ... Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and metabolites,although most studies have primarily focused on proteins and RNA.Recently,exosome metabolomics has demonstrated clinical value and potential advantages in disease detection and pathophysiology,despite significant challenges,particularly in exosome isolation and metabolite detection.This review discusses the significant technical challenges in exosome isolation and metabolite detection,highlighting the advancements in these areas that support the clinical application of exosome metabolomics,and illustrates the potential of exosomal metabolites from various body fluids as biomarkers for early disease diagnosis and treatment. 展开更多
关键词 EXOSOME Metabolomics body fluid BIOMARKER Disease diagnosis
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