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Measurement of emissivity with a new grey body and novel IR thermal sensor dubbed TMOS
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作者 Moshe Avraham Shlomi Bouscher +2 位作者 Jonathan Nemirovsky Yael Nemirovsky 《红外与毫米波学报》 北大核心 2025年第1期17-24,共8页
The concept of emissivity has been with the scientific and engineering world since Planck formulated his blackbody radiation law more than a century ago.Nevertheless,emissivity is an elusive concept even for ex⁃perts.... The concept of emissivity has been with the scientific and engineering world since Planck formulated his blackbody radiation law more than a century ago.Nevertheless,emissivity is an elusive concept even for ex⁃perts.It is a vague and fuzzy concept for the wider community of engineers.The importance of remote sensing of temperature by measuring IR radiation has been recognized in a wide range of industrial,medical,and environ⁃mental uses.One of the major sources of errors in IR radiometry is the emissivity of the surface being measured.In real experiments,emissivity may be influenced by many factors:surface texture,spectral properties,oxida⁃tion,and aging of surfaces.While commercial blackbodies are prevalent,the much-needed grey bodies with a known emissivity,are unavailable.This study describes how to achieve a calibrated and stable emissivity with a blackbody,a perforated screen,and a reliable and linear novel IR thermal sensor,18 dubbed TMOS.The Digital TMOS is now a low-cost commercial product,it requires low power,and it has a small form factor.The method⁃ology is based on two-color measurements,with two different optical filters,with selected wavelengths conform⁃ing to the grey body definition of the use case under study.With a photochemically etched perforated screen,the effective emissivity of the screen is simply the hole density area of the surface area that emits according to the blackbody temperature radiation.The concept is illustrated with ray tracing simulations,which demonstrate the approach.Measured results are reported. 展开更多
关键词 BLaCKbody grey body graybody cavity blackbody extended area blackbody EMISSIVITY IR thermometry remote temperature measurement
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Role of waist circumference-to-height ratio in assessing adiposity,predicting type 2 diabetes mellitus and other cardiometabolic diseases 被引量:3
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作者 ZHANG Xinyi LU Xi +2 位作者 PAN Xiaohui SHEN Sumin TONG Nanwei 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第7期1062-1072,共11页
Although body mass index(BMI)is widely used as a simple tool to assess obesity,it has certain limitations and inaccuracies.It is known that visceral adipose tissue is closely related to cardiometabolic risks and all-c... Although body mass index(BMI)is widely used as a simple tool to assess obesity,it has certain limitations and inaccuracies.It is known that visceral adipose tissue is closely related to cardiometabolic risks and all-cause mortality;however,precise measurement methods for visceral fat(magnetic resonance imaging and computed tomography)cannot be widely used.Thus,simple but accurate alternatives are valuable.Studies have shown that waist circumference-to-height ratio(WHtR)might be a superior and more accurate variable in assessing central or visceral adiposity as well as predicting risks of diabetes and other cardiometabolic diseases.Furthermore,WHtR cutoff values can be consistent across different races,age,and genders,making it a universal metric worth promoting and applying. 展开更多
关键词 waist circumference-to-height ratio body mass index DIaBETES cardiometabolic diseases central adiposity
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Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose 被引量:2
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作者 YANG Jie LIU Yanli +2 位作者 CHEN Xiaoyan CHEN Tianle LIU Qi 《中国医学影像技术》 CSCD 北大核心 2024年第8期1242-1248,共7页
Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were col... Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM. 展开更多
关键词 body composition THORaX muscle skeletal adipose tissue deep learning tomography X-ray computed
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Exploring the effects of angle of incidence on stabbing resistance in advanced protective textiles:Novel experimental framework and analysis
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作者 Mulat Alubel Abtew François Boussu Irina Cristian 《Defence Technology(防务技术)》 2025年第2期67-82,共16页
Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and... Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and performance of different types of protective textiles.Three distinct structures of 3D woven textiles and 2D plain weave fabric made with similar high-performance fiber and areal density were designed and manufactured to be tested.Two samples,one composed of a single and the other of 4-panel layers,from each fabric type structure,were prepared,and tested against stabbing at[0○],[22.5○],and[45○]angle of incidence.A new stabbing experimental setup that entertained testing of the specimens at various angles of incidence was engineered and utilized.The stabbing bench is also equipped with magnetic sensors and a UK Home Office Scientific Development Branch(HOSDB)/P1/B sharpness engineered knives to measure the impact velocity and exerted impact energy respectively.A silicon compound was utilized to imprint the Back Face Signature(BFS)on the backing material after every specimen test.Each silicon print was then scanned,digitized,and precisely measured to evaluate the stab response and performance of the specimen based on different performance variables,including Depth of Trauma(DOT),Depth of Penetration(DOP),and Length of Penetration(LOP).Besides,the post-impact surface failure modes of the fabrics were also measured using Image software and analyzed at the microscale level.The results show stab angle of incidence greatly influences the stab response and performance of protective textiles.The outcome of the study could provide not only valuable insights into understanding the stab response and capabilities of protective textiles under different angle of incidence,but also provide valuable information for protective textile manufacturer,armor developer and stab testing and standardizing organizations to consider the angle of incidence while developing,testing,optimizing,and using protective textiles in various applications. 展开更多
关键词 2D/3D woven fabrics Impact protective fabric Drop tower perforation test Stab resistance testing protocol angle of incidence Multi-layer panels Soft body armor Impact surface damage
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Effects of a 4-week internet-delivered mindfulness-based cancer recovery program on anxiety,depression,and mindfulness among patients with breast cancer
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作者 GU Can PENG Yunyun +3 位作者 PENG Yueyang LIN Sulan YAO Juqin CHEN Xing 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第7期1130-1142,共13页
Objective:The efficacy of monotherapy in alleviating psychological disorders like anxiety and depression among breast cancer patients is suboptimal,necessitating effective psychosocial interventions.Mindfulness-based ... Objective:The efficacy of monotherapy in alleviating psychological disorders like anxiety and depression among breast cancer patients is suboptimal,necessitating effective psychosocial interventions.Mindfulness-based interventions have been shown to mitigate anxiety-depression symptoms and encourage beneficial behaviors.The online mindfulness based cancer recovery(MBCR)offers flexibility and guides practice across various settings,facilitating full patient engagement.This study amis to analyze the impact of a 4-week internet-delivered mindfulness-based cancer recovery program on anxiety,depression,and mindfulness among Chinese patients with breast cancer,and to evaluate the degree of satisfaction breast cancer patients experienced after participating in this program.Methods:This study utilized a two-armed,parallel,randomized controlled trial design.A total of 103 patients with breast cancer from June 2020 to January 2021 in the ward of Breast and Thyroid Surgery of a tertiary hospital in Changsha,Hunan Province were selected and randomly assigned to an intervention group(n=51)and a control group(n=52).The intervention group participated in an internet-delivered mindfulness-based cancer recovery program,which was delivered once a week for 4 weeks.Meanwhile,the control group received weekly group health education for 4 weeks.The outcomes of hospital anxiety and depression scale and mindfulness Attention Awareness Scale were evaluated at 3 distinct time points:Baseline(T1),postintervention(T2),and 1-month follow-up(T3).The satisfaction questionnaire of 4-week mindful cancer rehabilitation training program was used at T2 to evaluate patients’satisfaction with the intervention program.Generalized estimation equations were used to assess differences in anxiety,depression and mindfulness levels between groups before and after the intervention.Results:There were no statistically significant differences in demographic data and outcome index scores between the 2 groups at T1(all P>0.05),indicating that the 2 groups were comparable.The generalized estimating equation analyses showed that the intervention group had significantly better improvement in outcomes compared to the control group,particularly for anxiety(T2β=−1.30,95%CI−1.87 to−0.72;T3β=−2.78,95%CI−3.51 to−2.05)and depression(T2β=−1.92,95%CI−2.78 to−1.06;T3β=−2.96,95%CI−4.05 to−1.87;all P<0.001).Moreover,the mindfulness score in the intervention group was significantly higher than that in the control group at T2(β=3.23,95%CI 0.73 to 5.72)and T3(β=8.06,95%CI 4.37 to 11.75;both P<0.05).In addition,patients in the intervention group were satisfied with the 4-week mindfulness-based cancer recovery intervention and teaching/learning activities used to implement the program.Conclusion:In patients with breast cancer,the 4-week internet-delivered mindfulness based cancer recovery program,as a low-threshold,short-term mental health intervention,has a positive effect on reducing anxiety and depression and improving mindfulness levels.This program holds great promise as a tool for clinical nursing practice,given the high satisfaction and applicability. 展开更多
关键词 mindFULNESS aNXIETY DEPRESSION breast cancer internet-based interventions
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Effects of immersion in simulated body fluid on the fatigue and corrosion behavior of biodegradable WE54 magnesium alloy
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作者 N.ASGHARINEZHAD BALOOCHI A.R.EIVANI +1 位作者 M.R.ABOUTALEBI H.R.JAFARIAN 《Journal of Central South University》 CSCD 2024年第11期3996-4012,共17页
Fatigue and tensile behaviors of homogenized WE 54 magnesium alloy before and after immersion in simulated body fluid(SBF)were investigated.According to the tensile test,the alloy without immersion in SBF solution has... Fatigue and tensile behaviors of homogenized WE 54 magnesium alloy before and after immersion in simulated body fluid(SBF)were investigated.According to the tensile test,the alloy without immersion in SBF solution has the highest tensile strength of 278 MPa,which decreased to 190 MPa after 336 h of immersion..The fatigue life of the homogenized WE 54 magnesium alloy before immersion in the SBF solution under a constant stress of 15 MPa is 3598 cycles.However,the fatigue life of the alloy decreased to 453 cycles after 336 h of immersion in the SBF solution under the same stress.Examination of the fracture surface of the samples by SEM reveals that the origin of the fatigue crack before immersion is micro-pores and defects.While corrosion pits and cracks are the main reasons for forming the initial fatigue crack after immersion.Moreover,the results obtained from practical work were evaluated and compared to theoretical calculations.The area of the hysteresis loops of the samples after the fatigue test,determined using Triangles and Monte Carlo methods,decreased from 4954.5 MPa and 4842.9 MPa before immersion to 192.0 MPa and 175.8 MPa after 336 h of immersion,respectively. 展开更多
关键词 WE54 magnesium alloy BIODEGRaDaBILITY corrosion FaTIGUE simulated body fluid
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The Change of Plasm a very Low Density Lipoprotein Concentration Pre-or Post-Feeding and in Conrrelation with Body Fatness Traits in Broiler Chickens 被引量:1
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作者 Li Hui, Yu He, Gong Dao qing, Zhang De xiang (College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030,PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第2期100-106,共7页
Blood samples were taken from birds,from a commercial line of broiler chicken,being in a fully fed state and in fasting state for 2,4,6 hours respectively at 49 d of age and plasma very low density lipoprotein(VLDL) c... Blood samples were taken from birds,from a commercial line of broiler chicken,being in a fully fed state and in fasting state for 2,4,6 hours respectively at 49 d of age and plasma very low density lipoprotein(VLDL) concentration was measured with turbidimetric assay.The experiment results showed that the variation coefficients of plasma VLDL concentration mersured at four different times were 58.11%,74.39%,69.70%,47.83%,respectively for male broilers,and 41.82%,60.87%.59.26%,50.0%for female broilers respectively.Plasma VLDL concentration decreased with the fasting time.There was a significant positive phenotypic correlation between abdominal fat weight,percentage of abdominal fat and plasma VLDL concentration for the birds being in fully feeding state,and the correlation decreased or no longer existed for the bired being in fasting state.The conclusion was that for practically application of plasma VLDL content selected in broiler chicken breeding,blood samples should be collected from birds being in feeding state. 展开更多
关键词 broiler chickens plasma VLDL concentration body fatness traits
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基于Landsat的黑河流域水体识别方法与时空演变
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作者 赵文举 谢振东 +3 位作者 徐文 俞海英 战国隆 王之君 《农业机械学报》 北大核心 2025年第8期152-162,共11页
针对黑河流域大尺度环境下水体提取难度大、演变规律尚不明晰等问题,基于谷歌地球引擎(Google Earth Engine,GEE)处理黑河流域1986—2024年Landsat影像,采集7.8×10^(4)个水体/非水体样本并构建逐年样本数据集,通过将多波段水体指数... 针对黑河流域大尺度环境下水体提取难度大、演变规律尚不明晰等问题,基于谷歌地球引擎(Google Earth Engine,GEE)处理黑河流域1986—2024年Landsat影像,采集7.8×10^(4)个水体/非水体样本并构建逐年样本数据集,通过将多波段水体指数(Multi band water index,MBWI)、增强型水体指数(Enhanced water index,EWI)、改进归一化差异水体指数(Modified normalized difference water index,MNDWI)与光谱波段进行单独与统一组合,构建并筛选出最佳融合水体指数的随机森林(Random forest,RF)水体提取方法,提取了研究区39个时相的逐年地表水体影像,采用曼-肯德尔(Mann-Kendall,M-K)法揭示了黑河流域逐年地表水体面积变化特征,基于主成分与敏感性分析探究了影响地表水体演变的主要驱动因素。结果表明:融合3种水体指数(MBWI、EWI、MNDWI)的随机森林水体提取方法对黑河流域Landsat影像的水体提取效果最佳,平均总体精度(Overall accuracy,OA)为96.16%,平均Kappa系数为0.9128;经M-K法检验,黑河流域1986—2024年地表水体面积呈波动减少态势;年降水量、人口、年蒸散量为黑河流域地表水体演变的最主要驱动因素。研究结果可为全流域地表水体的快速准确提取提供理论支持。 展开更多
关键词 水体识别 Landsat卫星 水体指数 时空演变 黑河流域
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融合GLAS与Landsat的湖泊蓄水量季节性监测及预测
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作者 王振华 刘存锟 +2 位作者 张熙 王凤香 刘向锋 《海洋测绘》 CSCD 北大核心 2024年第4期74-78,共5页
为实现高海拔区域湖泊蓄水量监测与预测,提出了一种融合ICESat/GLAS与Landsat数据监测并预测湖泊蓄水量季节性变化的方法。利用随机森林对GLAS激光脚点自动分类,解决湖面非水体与水体目标分类难的问题;结合水体指数和大津法自动分割Land... 为实现高海拔区域湖泊蓄水量监测与预测,提出了一种融合ICESat/GLAS与Landsat数据监测并预测湖泊蓄水量季节性变化的方法。利用随机森林对GLAS激光脚点自动分类,解决湖面非水体与水体目标分类难的问题;结合水体指数和大津法自动分割Landsat数据中的水体,降低不规则边界的影响;联合GLAS和Landsat数据,构建高时间分辨率的水位、面积与蓄水量时序列变化关系,解决两类数据观测信息缺失及观测时间不匹配的问题;并利用LSTM模型,预测蓄水量变化。以西藏纳木错湖为例,对上述方法进行验证,结果显示2003-2009年纳木错湖水位上升1.15 m,面积增加25.58 km2,蓄水量增加2.30 km^(3);预测2010-2016年蓄水量增加1.16 km^(3),与实际情况相符。结果表明,该方法可为生态环境的动态监测提供数据支撑。 展开更多
关键词 激光脚点分类 蓄水量预测 水位计算 水体分类 季节性监测
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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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Shear stress distribution and characteristics of deformation for shear band-elastic body system at pre-peak and post-peak 被引量:2
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作者 王学滨 《Journal of Central South University of Technology》 EI 2005年第5期611-617,共7页
The distributed shear stress and the displacement across shear band, the evolution of plastic zones, and the load-carrying capacity of rock specimen were investigated in plane strain direct shear test according to Fas... The distributed shear stress and the displacement across shear band, the evolution of plastic zones, and the load-carrying capacity of rock specimen were investigated in plane strain direct shear test according to Fast Lagrangian Analysis of Continua (FLAC). And then the shear displacement distribution in normal direction of system composed of localized shear band and elastic rock was analyzed based on gradient-dependent plasticity. The adopted failure criterion was a composite of Mohr-Coulomb criterion, that is, the relation between tension cut-off and postpeak constitutive of rock was linear strain-softening. Numerical results show that shear stress field approximately undergoes three different stages. At first, shear stress is only concentrated in the middle of top and base of specimen. Next, shear stress in the middle of specimen tends to increase, owing to superposition of shear stresses. Interestingly, two peaks of shear stress appear far from the loading ends of specimen, and the peaks approach with the increase in timestep until elements at the center of specimen yield. Finally, relatively lower shear stress level is reached in large part of specimen except in the regions near the two ends. As flow stress decreases, the analytical shear displacement distribution in shear band based on gradient-dependent plasticity becomes steeps outside the band, it is linear and its slope tends to decrease. These theoretical results qualitatively agree with that of the present numerical predicted results. Main advantage of the analytical solution over the numerical results according to FLAC is that it is continuous, smooth and non-linear (except at elastic stage). 展开更多
关键词 shear stress shear displacement plane strain strain softening gradient-dependent plasticity shear band-elastic body system
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Synthesis,characterization and biological activity in vitro of FeCrAl(f)/HA asymmetrical biological functionally gradient materials 被引量:1
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作者 杨海林 李婧 +3 位作者 方华婵 周忠诚 童晓阳 阮建明 《Journal of Central South University》 SCIE EI CAS 2014年第2期447-453,共7页
FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test ... FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test machine were utilized to characterize the microstructure,component,mechanical properties and the formation of the Ca-deficient apatite on the surface of these materials.The results indicate that an asymmetrical FeCrAl(f)/HA FGM,consolidating powders prepared by mixing HA with 3%–15%(volume fraction) is successfully prepared.Both of the matrix and FeCrAl fiber are integrated very tightly and bite into each other very deeply.And counter diffusion takes place to some extent in two phase interfaces.The elemental compositions of the FeCrAl(f)/HA FGM change progressively.Ca and P contents increase gradually with immersion time increasing,and thereafter approach equilibrium.The bone-like apatite layer forms on the materials surface,which possesses benign bioactivity,and the favorable biocompatibility can provide potential firm fixation between FeCrAl(f)/HA asymmetrical FGM implants and human bone. 展开更多
关键词 hydroxyapatite(Ha FeCral fiber functionally gradient material(FGM) simulated body fluid(SBF) bone-like apatite
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Analysis of the Main Body the Object and their Relationship Concerning Research of Traditional Chinese Medicine
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作者 SU Yan-bin MENG Xian-sheng +1 位作者 SU Yan-wen SI Ying-kui 《中华中医药学刊》 CAS 2007年第2期344-347,共4页
This paper is the analysis of the main body, the object and their relationship concerning research of traditional Chinese medicine. The result proved that the main body of research of traditional Chinese medicine is r... This paper is the analysis of the main body, the object and their relationship concerning research of traditional Chinese medicine. The result proved that the main body of research of traditional Chinese medicine is researchers who possessed the fundamentals of traditional Chinese medicine. It is the objects of research of traditional Chinese medicine that origin of a class of traditional Chinese medical literature consisting of herbals which focus on descriptions of individual drugs; the relationship of the technological process of preparing Chinese medicine, as by parching, roasting, baking, steaming, soaking, and simmering, etc.;and technology of separating, extracting and purifying for composition; traditional Chinese medicine dynamics of one of the 12 two-hour periods into which the day was formerly divided before the introduction of western chronology; compatibility of medicines in active compositions; patent, effectiveness for a given period of time and constantly changing of traditional Chinese medicine.The relationship between the main body and the objects was that the former depends on the latter ones and the main body has subjective initiative as fully as possible. 展开更多
关键词 Research of traditional Chinese medicine main body OBJECTS RELaTIONSHIP
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Endocrine Changes and Their Relationships with Body weight of Growing Yak
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作者 田永强 《中国草食动物》 2005年第z2期211-214,共4页
Concentrations of growth hormone (GH), insulin, thyroxin(T4 ) and 3,3 ' 5 '-tri-iodothyronine (T3)in blood samples of growing yak during different seasons were determined by radio-immunoassay.Changes in bodywe... Concentrations of growth hormone (GH), insulin, thyroxin(T4 ) and 3,3 ' 5 '-tri-iodothyronine (T3)in blood samples of growing yak during different seasons were determined by radio-immunoassay.Changes in bodyweight of the growing yak and compositions of grass were also measured. The seasonal changes in hormones were significant (at least P<0.05). In the same season, variation in hormonal concentration was affected by the growth stage of the animal. The bodyweight gains varied in different seasons, with significant increase from May to September and decrease from January to May. Correlation analysis indicated that T4 had a significant positive correlation with bodyweight of the growing yak(r= 0.323,P<0.05) ,but other hormones did not have significant correlations with bodyweight. The results show that annual cycle of weight loss and gain is attributable to the seasonal changes in feed supply and that the seasonal changes in the concentrations of the assayed hormones were indirectly dependent on grass growth. 展开更多
关键词 body WEIGHT correlation growth HORMONE YaK
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Stature Estimation Based on the Length of Tibia and Fibula Measured by Digital X-ray in Chinese Han Teenagers 被引量:1
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作者 WANG Yu-zhuo HUANG Yun +1 位作者 ZHOU Xiao-rong DENG Zhen-hua 《法医学杂志》 CAS CSCD 2012年第6期413-417,425,共6页
Objective To derive regression formulae for stature estimation using forensic radiography from the tibia and fibula of Chinese Han teenagers in Sichuan Province. Methods To construct equations, measurements were condu... Objective To derive regression formulae for stature estimation using forensic radiography from the tibia and fibula of Chinese Han teenagers in Sichuan Province. Methods To construct equations, measurements were conducted on the training sample (412 adults, 201 males and 211 females). The whole length of the fibula and four measurements of tibia were determined using CR radiography, rectified through theoretical magnification. The regression formulae were relatively constructed to the real stature measured in an erect position. Through using the testing sample (40 adults) for the regression formulae, the reliability of the regression formulae was assessed. Results The range of correlation coefficients of four measurements for tibia was 0.880-0.895 in the sex-unknown group, 0.869-0.893 in the male, and 0.8450.855 in the female. The five measurements were found to be better correlated with stature in the male than in the female. Conclusion The digital X-ray of the tibia and fibula for stature estimation is proved to be effective in forensic individual identification; therefore, these equations can be of great assistance to the stature estimation of the contemporary Chinese Han teenagers. 展开更多
关键词 胫骨 腓骨 法医 个体识别
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Vertical structure and dominating factors of sand body during Late Triassic Chang 9 time of Yanchang Formation in Ordos Basin, NW China
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作者 丁熊 陈景山 +5 位作者 谭秀成 林丹 赵子豪 姚泾利 邓秀芹 李元昊 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1405-1418,共14页
Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9sand body in Odors Basin were recognized, which included two effects, that is, delta environment ... Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9sand body in Odors Basin were recognized, which included two effects, that is, delta environment and tractive current effects that lead to the development of mouth bar, distal bar, sheet sand and other sand bodies of subaerial and subaqueous distributary channel,natural levee, flood fan and delta front, and shore-shallow lake environment and lake flow transformation effects that result in the development of sandy beach bar, sheet sand and other sand bodies. Chang 9 sand body mainly developed five basic vertical structures, namely box shape, campaniform, infundibuliform, finger and dentoid. The vertical stacking patterns of multilayer sand body was complex, and the common shapes included box shape + box shape, campaniform + campaniform, campaniform + box shape, infundibuliform + infundibuliform, campaniform + infundibuliform, box shape + campaniform, box shape + infundibuliform,and finger + finger. Based on the analysis on major dominating factors of vertical structure of sand body, sedimentary environment,sedimentary facies and rise, fall and cycle of base level are identified as the major geological factors that control the vertical structure of single sand body as well as vertical stacking patterns and distribution of multistory sand bodies. 展开更多
关键词 vertical structure stacking pattern sand body Chang 9 time Ordos Basin
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A Review on the Evolution and Development of Searle' s Philosophy of Mind
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作者 Zhao Yingji 《学术界》 CSSCI 北大核心 2013年第12期291-299,共9页
The evolution and development of Searle’s philosophy of mind can be divided into two important stages,i.e.the origin and beginning stage between 1960sand 1970s,the formation and development stage since 1980s.Searle’... The evolution and development of Searle’s philosophy of mind can be divided into two important stages,i.e.the origin and beginning stage between 1960sand 1970s,the formation and development stage since 1980s.Searle’s Speech Act Theory started the research on philosophy of mind,which is considered as the origin of his philosophy of mind.The Theories of Intentionality and Chinese Room Argument are the most important and most influential academic findings in his research in the field of philosophy of mind,which lay a solid theoretical foundation for the formation and development of his theories of philosophy of mind.Searle’s philosophy of mind finds wide prospect in the research field,which provides a new direction to understand the world and probe into mind,proposes a new perspective and methodology for the study of language,and promotes the new development of the study of language. 展开更多
关键词 心灵哲学 塞尔 述评 演进 心境 言语行为理论 学术成果 意向性
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Review of the Modeling, Simulation and Implement of Intra-body Communication
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作者 SONG Yong HAO Qun ZHANG Kai 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第1期11-20,共10页
Intra-body communication (IBC) is a technology using the human body as a transmission medium for electrical signals. Compared with the short distance wireless communication technologies, it has several novel character... Intra-body communication (IBC) is a technology using the human body as a transmission medium for electrical signals. Compared with the short distance wireless communication technologies, it has several novel characteristics. The modeling, simulation and implement of intra-body communication are reviewed. Firstly, the transfer function of the galvanic coupling IBC is deduced, and the in vivo measurements results and the corresponding mathematical simulations results based on the proposed transfer function are discussed. Secondly, a finite-element method for modeling the whole human body is introduced, and the simulation results of the galvanic coupling IBC based on the whole human body and the corresponding in vivo measurement results are discussed. Finally, the implement methods of the intra-body communication as well as a novel IBC system based on Mach-Zehnder EO modulator are introduced and analyzed, while some conclusions are achieved. 展开更多
关键词 intra-body communication MODELING SIMULaTION
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A comparison of elderly (20~65 yrs) life style with body mass index (BMI)25
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作者 M.Saeed Heydarnejad Ali Hassanpour Dehkordi 《海南医学院学报》 CAS 2010年第3期311-314,共4页
Objective:compare the habits and features of obese (BMI>25) and normal (BMI<25) individuals and express a method to ameliorate the life styles using a cross-sectional experiment.Methods:A total of 220 randomly s... Objective:compare the habits and features of obese (BMI>25) and normal (BMI<25) individuals and express a method to ameliorate the life styles using a cross-sectional experiment.Methods:A total of 220 randomly selected cases were divided into case group (n=110) and control group (n=100) according to the calculated BMI level.Samples with BMI>25 kg/m2 were assigned to the case (obsess) group and those with BMI ranging from 20 to 25 were assigned to control (normal) group.The Miller-Smith life style questionnaires consisting 20 questions each with 5 different answers were given to both groups.Data of the questionnaires were collected and analyzed using t-test and Chi-square with SPSS.Results:No significant differences were found among the two groups in terms of the mean age,gender,level of education,marital status,insurance,breakfast,lunch or dinner,fried meat,legumes,caffeinated beverages,the length of sleep during 24 h,cigarette smoking and losing job or spouse.However,in regards to use of vegetables,sausage,fried potatoes,enriched breads,low fat milk,low salt,candies and chocolates significant relations were found (P<0.05).Conclusion:The present study suggests one way to control obesity and prevent diseases is to ameliorate the life styles.There is a relation between health and stress and irregularity of meals,such as breakfast skipping,is associated with overweight and obesity in adolescence. 展开更多
关键词 肥胖病 个人卫生 保健知识 治疗方法 预防措施
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Effect of body material and temperature variation on the performance of the time delay pyrotechnic compositions
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作者 Azizullah Khan Abdul Qadeer Malik +1 位作者 Zulfiqar Hameed Lodhi Zain Ul Abdin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第3期261-265,共5页
Significance of body material and temperature variation on burning time and burning rate of Si/Pb O/Pb_3O_4/FG and B/BaCrO_4/FG pyrotechnic delay compositions were experimentally studied. Brass and stainless steel wer... Significance of body material and temperature variation on burning time and burning rate of Si/Pb O/Pb_3O_4/FG and B/BaCrO_4/FG pyrotechnic delay compositions were experimentally studied. Brass and stainless steel were used as delay body materials. High resolution oscilloscope and a customized chronometer were simultaneously used for the measurement of burning time and burning rate. Results reveal that brass material with controlled column dimensions reduced the variation in burning time of Si/Pb O/Pb_3O_4/FG delay mixture from 7.43% to 4.17% and that of B/Ba CrO_4/FG mixture from 16.83% to 9.39%.Similarly the variation in burning rate was reduced from 7.57% to 4.12% and from 17% to 9.69% for Si/Pb O/Pb_3O_4/FG and B/BaCrO_4/FG mixtures respectively. Si/PbO/Pb_3O_4/FG delay mixture was also subjected to temperature ranging from -54℃ up to+100℃. The burning rate of this composition varied linearly with temperature. Burning rate increased from 28.01 mm/s to 34.38 mm/s when the temperature was varied from -54℃ to +100℃. 展开更多
关键词 温度变化 体材料 时间 烟火 身体 表演 混合物 高分辨率
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