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Serum proteins differentially expressed in gestational diabetes mellitus assessed using isobaric tag for relative and absolute quantitation proteomics
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作者 Wei-Li Cao Cui-Ping Yu Ling-Li Zhang 《World Journal of Clinical Cases》 SCIE 2024年第8期1395-1405,共11页
BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients a... BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients and their altered expression in the serum,proteomics techniques were deployed to detect the differentially expressed proteins(DEPs)of in the serum of GDM patients to further explore its pathogenesis,and find out possible biomarkers to forecast GDM occurrence.METHODS Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria.Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation,and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry.Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis,and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA).RESULTS Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDMgravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteinsassociated with lipid metabolism, coagulation cascade activation, complement system and inflammatory responsein the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serumof GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk ofgestation.CONCLUSION GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complementsystem and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM. 展开更多
关键词 Gestational diabetes mellitus Liquid chromatography-tandem mass spectrometry Isobaric tag for relative and absolute quantitation PROTEOMICS BIOMARKER
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Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion 被引量:5
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作者 张美玲 孙现亭 +2 位作者 王肖肖 解银丽 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期19-22,共4页
Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a ... Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups is given. The expression of generalized Hojman conserved quantity deduced directly from Lie symmetry for a variable mass holonomic system of relative motion is obtained. An example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Lie symmetry generalized Hojman conserved quantity
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Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion 被引量:3
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作者 张美玲 王肖肖 +1 位作者 韩月林 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期17-21,共5页
Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion are studied.The definition and criterion of the Mei symmetry of Appell equations for a variable mass ... Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion are studied.The definition and criterion of the Mei symmetry of Appell equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups are given.The structural equation of Mei symmetry of Appell equations and the expression of Mei conserved quantity deduced directly from Mei symmetry for a variable mass holonomic system of relative motion are gained.Finally,an example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Appell equations Mei conserved quantity
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Spectrum-effect relationship between HPLC fingerprints and bioactive components of Radix Hedysari on increasing the peak bone mass of rat 被引量:6
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作者 Xin-Yue Chen San-Hu Gou +2 位作者 Zhi-Qiang Shi Zhi-Yuan Xue Shi-Lan Feng 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第4期266-273,共8页
The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in c... The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value. 展开更多
关键词 Factor ANALYSIS GRAY relatIONAL ANALYSIS Hierarchical cluster ANALYSIS PEAK BONE mass RADIX Hedysari Spectrum-effect relationship
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THE CONSTITUTIVE RELATION OF CRACK-WEAKENED ROCK MASSES UNDER AXIAL-DIMENSIONAL UNLOADING 被引量:4
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作者 Xiaoping Zhou Qihu Qian Yongxing Zhang 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第3期221-231,共11页
An accurate and efficient numerical method for solving the crack-crack interaction problem is presented. The method is mainly by means of the dislocation model, stress superposition principle and Chebyshev polynomial ... An accurate and efficient numerical method for solving the crack-crack interaction problem is presented. The method is mainly by means of the dislocation model, stress superposition principle and Chebyshev polynomial expansion of the pseudo-traction. This method can be applied to compute the stress intensity factors of multiple kinked cracks and multiple rows of periodic cracks as well as the overall strains of rock masses containing multiple kinked cracks under complex loads. Many complex computational examples are given. The dependence of the crack-crack interaction on the crack configuration, the geometrical and physical parameters, and loads pattern, is investigated. By comparison with numerical results under confining pressure unloading, it is shown that the crack-crack interaction under axial-dimensional unloading is weaker than those under confining pressure unloading. Numerical results for single faults and crossed faults show that the single faults are more unstable than the crossed faults. It is found from numerical results for different crack lengths and different crack spacing that the interaction among kinked cracks decreases with an increase in length of the kinked cracks and the crack spacing under axial-dimensional unloading. 展开更多
关键词 interaction among cracks axial-dimensional unloading crack-weakened rock masses the stress-strain relation the Chebyshev polynomial expansion
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Analysis of ganciclovir and its related substances using high performance liquid chromatography and liquid chromatography-mass spectrometry methods 被引量:1
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作者 Cheng-Ping Li1,2,Mao Mao1,Lan-Jun Zheng1,Wei-Guang Shan11.College of Pharmaceutical Sciences,Zhejiang University of Technology,Hangzhou 310032 2.College of Biology and Environment Engineering,Zhejiang Shuren University,Hangzhou 310015,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2010年第4期218-222,共5页
Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 co... Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 column(4.6 mm×250 mm,5 μm)was used with a mobile phase of 0.02 M potassium dihydrogen phosphate buffer(pH 6.0)-methanol(92∶8)at a flow rate of 1.0 mL/min,and UV detector set at 254 nm was used for monitoring the eluents.Results The method was simple,rapid,selective and capable of separating all related substances at trace level with a detection limit of 0.04 μg/mL.It has been validated with respect to accuracy,precision,linearity,and limits of detection and quantification.The linearity range was 10.2-153.0 μg/mL with r=0.9998.The percentage recoveries ranged from 96.7% to 101.6%,and RSD was 1.24%-1.96%(n=5).Conclusion The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir.For identification of related substances,LC/MS was used.The mainly related substances of ganciclovir active pharmaceutical ingredients(API)were determined as guanine,(1,3-dioxolan-4-yl)methyl acetate,and diacetyl guanine. 展开更多
关键词 GANCICLOVIR related substances high performance liquid chromatography high performance liquid chromatography/mass spectrometry
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Reciprocity Relation between the Mass Constituents of the Universe and Hardy’s Quantum Entanglement Probability 被引量:2
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作者 Hans Hermann Otto 《World Journal of Condensed Matter Physics》 2018年第2期30-35,共6页
In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-t... In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-theoretical argumentation, the relation may also be a consequence of a coupling factor attributed to the normed dimensions of the universe. Also, very simple expressions for the mass amounts were obtained, when replacing the Golden Mean φ by the Archimedes’ constant π. A brief statement was devoted to the similarity between the E-Infinity Theory of El Naschie and the Information Relativity Theory of Suleiman. In addition, superconductivity was also linked with Hardy’s entanglement probability. 展开更多
关键词 UNIVERSE mass Constituents Golden Mean Archimedes’ Constant RECIPROCITY relatION E-INFINITY THEORY Information relativity THEORY Entanglement Superconductivity
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Cigarette smoking,body mass index associated with the risks of age-related cataract in male patients in northeast China 被引量:8
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作者 Zhi-Quan Lu Wen-Hui Sun +3 位作者 Jia Yan Teng-Xuan Jiang Shu-Na Zhai and Yan Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第3期317-322,共6页
AIM: To determine the association between cigarettes smoking, body mass index (BMI) and the risk of age-related cataract (ARC) in middle-aged and elderly men in Northeast China. METHODS: A hospital-based case control ... AIM: To determine the association between cigarettes smoking, body mass index (BMI) and the risk of age-related cataract (ARC) in middle-aged and elderly men in Northeast China. METHODS: A hospital-based case control study was conducted. Cases (n =362) were men who had surgically treated ARC, 45-85 years old; controls frequency-matched (n=362) were men who had been admitted to the same hospital as cases for other diseases not related with eye diseases. Cases and controls were matched with 1:1. The cases and controls were interviewed during their hospital stay, using a structured interviewer-administrated questionnaire that included information on sociodemographic characteristics, socioeconomic, lifestyle habits (tobacco smoking and alcohol consumption, etc.), anthropometric measures, personal medical history, and family history of ARC in first-degree relatives, and simultaneously BMI was calculated. The odds ratios (OR) and 95% confidence intervals (CI) of ARC were estimated using multiple logistic regression models. RESULTS: After adjusting for age and multiple potential confounders, higher BMI was associated with an increased risk of ARC. Cigarette smoking, years smoking or moderate cigarette smoking (1-29 cigarettes per day) had no relation with the risk of ARC (P>0.05), although patients smoking >= 30 cigarettes per day had an elevated risk of ARC as compared with the non-smokers (OR=1.55, 95% CI; 1.16-2.85, P=0.026). Higher BMI was associated with an increased risk of ARC. Both overweight and obesity was associated with an obviously increased risk for surgically ARC (OR=1.55, 95% CI:1.02-1.98, P=0.015 and OR=1.71, 95% CI:1.32-2.39, P=0.013 respectively) compared to normal BMI. Then participants were grouped into quartiles of BMI (Q1 to Q4), compared to controls in the lowest quartile, the ORfor cases in the highest quartile of BMI was 1.54 (OR=1.54, 95% CI: 1.08-2.46, P=0.022). The results of univariate analysis showed cigarette smoking was not associated with ARC formation for men with lower or normal BMI (P >0.05). Compared to the non-smokers, for men of overweight or obesity, cigarette smoking was associated with a significantly increased risk for surgically ARC (OR=2.00, 95% CI: 1.49-6.65, P=0.003 and OR=1.66, 95% CI: 1.63-13.21, P=0.002 respectively). Similarly, smokers in the highest quartile of BMI had approximately 1.5 times the risk of ARC as non-smokers in the lowest quartile (OR =1.46, 95% CI: 1.06-5.29, P<0.001). Followed multivariate models revealed that the association had never changed. CONCLUSION: Current cigarette smoking is positively related to ARC only among those who smoking 30 or more cigarettes per day. For men who are both overweight and obesity, cigarette smoking is associated with a significantly increased risk for ARC. 展开更多
关键词 age-related cataract MALE SMOKING body mass index RISK
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Body Mass Index and Health Related Physical Fitness in Saudi Girls and Adolescents Aged 8 - 15 Years 被引量:3
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作者 Zahra A. Al-Asiri Afaf A. M. Shaheen 《Open Journal of Therapy and Rehabilitation》 2015年第4期116-125,共10页
Health related physical fitness (HRPF) is considered to be an indirect marker of a person’s health and wellbeing, reflecting the interplay and integration of many persons’ systems and body functions. Purpose: To inv... Health related physical fitness (HRPF) is considered to be an indirect marker of a person’s health and wellbeing, reflecting the interplay and integration of many persons’ systems and body functions. Purpose: To investigate the relationship between body mass index (BMI) and HRPF in a national cross-sectional sample of Saudi girls and adolescents. Methods: Weight, height and four components of HRPF (body fat composition, strength and endurance, flexibility and cardio-respiratory fitness) were measured in three age groups [(8 - 10), (11 - 12) and (13 - 15) years]. Pearson correlation coefficient and regressions analysis using a non-linear quadratic model were used to evaluate the relationship between BMI and HRPF in three age groups. Results: The results revealed variable relationships among tests. Lower scores in body fat composition and cardio-respiratory fitness were associated with higher body mass indexes in each age group. Also lower scores in muscle strength and endurance were recorded in girls aged from 11 to 15 years. Relationships between BMI and flexibility differed among age groups. Conclusion: BMI significantly and differentially influenced individual HRPF, but effects varied with age. Higher body mass indexes were generally associated with lower HRPF. The level of HRPF determined by this study may serve as an indicator of potential health risks that overweight and obese children girls and adolescents faced. 展开更多
关键词 BODY mass Index SAUDI Children GIRLS and Adolescents HEALTH-relatED Physical FITNESS
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Strength and deformation characteristics of irregular columnar jointed rock mass: A combined experimental and theoretical study 被引量:2
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作者 Xiangcheng Que Zhende Zhu +2 位作者 Yanxin He Zihao Niu Haonan Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期429-441,共13页
The irregularity of jointed network poses a challenge to the determination of field mechanical param-eters of columnar jointed rock mass(CJRM),and a reasonable prediction of deformation and strength characteristics of... The irregularity of jointed network poses a challenge to the determination of field mechanical param-eters of columnar jointed rock mass(CJRM),and a reasonable prediction of deformation and strength characteristics of CJRM is important for engineering construction.The Voronoi diagram and three-dimensional printing technology were used to make an irregular columnar jointed mold,and the irregular CJRM(ICJRM)specimens with different dip directions and dip angles were prepared.Uniaxial compression tests were performed,and the anisotropic strength and deformation characteristics of ICJRM were described.The failure modes and mechanisms were revealed in accordance with the final appearances of the ICJRM specimens.Based on the model test results,the empirical correlations for determining the field deformation and strength parameters of CJRM were derived using the dip angle and modified joint factor.The proposed empirical equations were used in the Baihetan Project,and the calculated mechanical parameters were compared with the field test results and those obtained from the tunneling quality index method.Results showed that the deformation parameters determined by the two proposed methods are all consistent with the field test results,and these two methods can also estimate the strength parameters effectively. 展开更多
关键词 Irregular columnar jointed rock mass (ICJRM) Physical model test Anisotropic characteristic Empirical relations Dip angle Modified joint factor
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A Revised Interpretation of the Thermodynamic Theory Including the Einstein Mass-Energy Relation <i>E</i>= <i>mc</i><sup>2</sup> 被引量:1
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作者 Jean-Louis Tane 《Journal of Applied Mathematics and Physics》 2020年第3期392-405,共14页
Thermodynamics being among the most synthetic theories of physics and the mass-energy relation E = mc2 among the most general equations of science, it is somewhat surprising that this latter is not explicitly present ... Thermodynamics being among the most synthetic theories of physics and the mass-energy relation E = mc2 among the most general equations of science, it is somewhat surprising that this latter is not explicitly present in the laws of thermodynamics. Coupling this observation with the conceptual difficulties often felt in learning thermodynamics leads to the idea that both situations may have the same cause. On the basis of these clues, this paper is intended to provide complementary arguments to a hypothesis already presented. It consists of showing the existence of an imperfect compatibility between the conventional formulations of the first and second laws of thermodynamics and suggesting the need of the mass-energy relation to solving the problem. 展开更多
关键词 Thermodynamics Entropy ENERGY Einstein’s mass-Energy relatION relativity
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General Derivation of Mass-Energy Relation without Electrodynamics or Einstein’s Postulates
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作者 Mario Rabinowitz 《Journal of Modern Physics》 2015年第9期1243-1248,共6页
The mass-energy equation ?is derived in general from Newton’s equation of motion without use of electrodynamics, or Einstein’s Postulates which were presented in his superb 1905 paper on Special Relativity (SR). Thi... The mass-energy equation ?is derived in general from Newton’s equation of motion without use of electrodynamics, or Einstein’s Postulates which were presented in his superb 1905 paper on Special Relativity (SR). This was previously not thought to be possible. This novel derivation of an accelerated body of rest mass m0 is compared with the traditional SR inertial derivation. A discussion is given of pre-1905, electrostatic and electrodynamic derivations of the mass-energy relation yielding , as well as more recent ones. A concise pre-relativity history of the mass-energy relation is traced back to Newton in 1717. 展开更多
关键词 mass-Energy relatION mass Variation Inertia EINSTEIN Newton Special relativity mass-Energy Origin mass-Energy History
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Colovesical fistula caused by glucocorticoid therapy for IgG4-related intrapelvic mass
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作者 Yohei Yabuuchi Hiroyuki Matsubayashi +5 位作者 Masato Matsuzaki Akio Shiomi Michihisa Moriguchi Ichiro Kawamura Ichiro Ito Hiroyuki Ono 《World Journal of Clinical Cases》 SCIE 2015年第12期1000-1004,共5页
IgG4-related disease(IgG4-RD) is an immune-mediated fibroinflammatory disorder that can occur in almost all systemic organs and generally responds to corticosteroid treatment. We report a rare case of an IgG4-related ... IgG4-related disease(IgG4-RD) is an immune-mediated fibroinflammatory disorder that can occur in almost all systemic organs and generally responds to corticosteroid treatment. We report a rare case of an IgG4-related intrapelvic mass lesion that responded to steroid therapy but caused a fistula between the sigmoid colon and bladder. A 71-year-old man was followed after treatment for hepatocellular carcinoma. Follow-up computed tomography(CT) incidentally depicted left hydronephrosis with an ill-demarcated intrapelvic mass lesion. This lesion was histologically diagnosed as IgG4-RD by open biopsy, and peroral steroid therapy was initiated. One month after starting steroids, a colovesical fistula was detected by follow-up CT. A colostomy and urethral catheterization were emergently performed. The patient recovered and the mass lesion was drastically minimized by the initiation of glucocorticoids; however, he still needs urethral catheterization. IgG4-RD develops in various systemic organs and generally responds well to steroids. Clinicians must be watchful for the complications of responses to corticosteroids, such as fistulization, when the mass lesion of IgG4-RD is adjacent to multiple luminal organs. 展开更多
关键词 IgG4-related disease Intrapelvic mass Steroid therapy Colovesical FISTULA COLOSTOMY URETHRAL CATHETERIZATION
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Priority Directions of National Policy of Regulation of Mutual Relations Between Youth and Mass Media: The Theoretical and Empirical Researches
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作者 Vera A. Gnevasheva 《Journal of Sociology Study》 2011年第3期179-186,共8页
关键词 大众媒体 青年社会化 传播媒介 俄罗斯 青少年 大众传媒 世界观 年轻人
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A Theoretical Study on Energy of a Gaseous System Vis-a-Vis Mass and Temperature
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作者 Santosh K. Karn Necati Demiroglu 《Journal of Electronics Cooling and Thermal Control》 CAS 2023年第1期1-8,共8页
To study various properties of a gas has been a subject of rational curiosity in pneumatic sciences. A gaseous system, in general, is studied by using four measurable parameters namely, the pressure, volume, number of... To study various properties of a gas has been a subject of rational curiosity in pneumatic sciences. A gaseous system, in general, is studied by using four measurable parameters namely, the pressure, volume, number of moles and temperature. In the present work, an attempt is made to study the variation of energy of an ideal gas with the two measurable parameters, the mass and temperature of the gas. Using the well known ideal gas equation, PV = nRT where symbols have their usual meanings and some simple mathematical operations widely used in physics, chemistry and mathematics in a transparent manner, an equation of state relating the three variables, the energy, mass and temperature of an ideal gas is obtained. It is found that energy of an ideal gas is equal to the product of mass and temperature of the gas. This gives a direct relationship between the energy, mass and temperature of the gas. Out of the three variables, the energy, mass and temperature of an ideal gas, if one of the parameters is held constant, the other two variables can be measured. At a constant temperature, when the power or energy is stabilized, the increase in the mass of the gas may affect the new works and an engine can therefore be prevented from overheating. 展开更多
关键词 HYDRODYNAMICS Low Temperature Fluid Flow Ideal Gas Equation of State ENERGY mass Temperature and Their relation
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Generation of Lepton Masses Complementary to Higgs
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作者 Peter I Porshnev 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期142-167,共26页
A generation of bare lepton masses alternative to Higgs-like mechanisms is proposed. It can be used in a combination with the latter ones in attempt to explain why the coupling strengths to Higgs field span a wide ran... A generation of bare lepton masses alternative to Higgs-like mechanisms is proposed. It can be used in a combination with the latter ones in attempt to explain why the coupling strengths to Higgs field span a wide range. The proposed mechanism also allows defining neutrino masses alternatively to the Dirac or Majorana types, since the effective bare masses of leptons are possible to generate without scalar terms in electroweak Lagrangians and motion equations. The proposed extension is fully compatible with standard methods of calculating radiative corrections and scattering amplitudes, since the left- and right-handed parts of EW Lagrangian do not change. 展开更多
关键词 Electroweak Left-Handed Lagrangian Dirac And Majorana masses Seesaw relation
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A Neo Explanation of the"Mass-Velocity Relation
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作者 Xu Shaozhi and Xu Xiangqun (Beijing Control Device Research Institute, P.O. Box 3913, Beijing 100854, P.R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第2期68-71,共4页
A reinterpretation of the well-known formula of the 'mass-velocity relation' is exactlyderived from a new viewpoint with new concepts, such as the finiteness of the transmitting velocityof force (TVF), effecti... A reinterpretation of the well-known formula of the 'mass-velocity relation' is exactlyderived from a new viewpoint with new concepts, such as the finiteness of the transmitting velocityof force (TVF), effective action, and the coupled effect of the TVF for two EM fields, etc. Then, atrue meaning hidden in the Lorentz factor is exploited : i.e., when a charged particle is moving at aspeed v under an EM field, the effective action exerted on it by the field varies inversely with thespeed ratio β= v / U, where U is the TVF, which probably is equal to the propagation velocity ofEM field. The actual reduction of the effective action gives a false impression of mass gain.Accordingly, it is a major mistake in orientation to ascribe the (genuine) electrodynamics of movingbodies to any observation, or to any motion of an observer, while disregarding the facts of mutualaction. 展开更多
关键词 relatIVITY Electrodynamics of moving bodies mass-velocity relation Lorentz factor Transmitting velocity of force Effective action Coupled effect.
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日地L5太阳探测工程概述
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作者 方成 丁明德 +5 位作者 陈鹏飞 李川 程鑫 郭洋 戴煜 李臻 《上海航天(中英文)》 CSCD 2024年第3期9-16,共8页
南京大学联合中国气象局、上海航天技术研究院等单位共同建议的日地L5太阳探测工程——“羲和二号”,将在国际上首次发射一颗人造探测器至日地系统第5个拉格朗日点,通过精测矢量磁场、揭示三维爆发和精准预警预报,解答“活动区磁场的产... 南京大学联合中国气象局、上海航天技术研究院等单位共同建议的日地L5太阳探测工程——“羲和二号”,将在国际上首次发射一颗人造探测器至日地系统第5个拉格朗日点,通过精测矢量磁场、揭示三维爆发和精准预警预报,解答“活动区磁场的产生演化及其与太阳爆发的物理联系”和“太阳爆发的传播规律及其与灾害性空间天气的关系”这2个太阳物理和空间天气领域亟待解决的重大科学和应用问题。本文重点阐述“羲和二号”的科学与应用目标,简要介绍其科学载荷和初步方案。联合日地连线方向上的太阳探测,“羲和二号”的实施将开启我国太阳立体探测时代,拓展人类对太阳爆发机制的理解,为空间天气预警预报带来革命性突破。 展开更多
关键词 太阳活动 太阳磁场 太阳耀斑 日冕物质抛射 日地关系
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“从爱因斯坦质能关系式推出勾股定理”之荒谬
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作者 葛惟昆 《物理与工程》 2024年第1期11-15,共5页
一本数学教科书提出并“证明”勾股定理可以用爱因斯坦质能关系式推导出来。教科书的编写者混淆了爱因斯坦少年时对勾股定理的简洁而睿智的纯数学推导,与多年后提出的著名的物理大发现——质能关系式。科学和教育界类似的荒谬贻害深远,... 一本数学教科书提出并“证明”勾股定理可以用爱因斯坦质能关系式推导出来。教科书的编写者混淆了爱因斯坦少年时对勾股定理的简洁而睿智的纯数学推导,与多年后提出的著名的物理大发现——质能关系式。科学和教育界类似的荒谬贻害深远,必须予以澄清。 展开更多
关键词 勾股定理 质能关系式 荒谬
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流动空间权力关系的建构与现实转换——对卡斯特传播权力理论的历史唯物主义考察
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作者 黄其洪 任艳华 《西南大学学报(社会科学版)》 北大核心 2024年第2期95-105,共11页
随着全球信息技术的革新,卡斯特将具有虚拟性、开放性、全球化等特征的流动空间设定为网络社会特有的空间形式,并以此为前提对流动空间中权力关系的建构及其现实转换进行了系统性的考察。在现实的推动下,卡斯特认为流动空间中的权力关... 随着全球信息技术的革新,卡斯特将具有虚拟性、开放性、全球化等特征的流动空间设定为网络社会特有的空间形式,并以此为前提对流动空间中权力关系的建构及其现实转换进行了系统性的考察。在现实的推动下,卡斯特认为流动空间中的权力关系存在着权力主体从精英转向大众、权力载体从网络公共空间走向城市公共空间、权力变革目标从政治改革通向社会变革的可能性。这种现实转换发生的条件首先在于作为流动空间权力关系新载体的大众自传播的兴起,另一个更为基础的条件则是处于被权力压制的大众通过对恐惧情绪的克服推动了网络社会运动向前发展,并且具有重建公共空间的潜力。卡斯特以流动空间中的权力关系为研究对象所建构起来的具有历史唯物主义特质的理论构想,为数字时代的政治改革、社会变革、人的自由解放以及国际新秩序的构建等重大现实议题注入了思想活力。 展开更多
关键词 流动空间 权力关系 大众自传播 数字时代 网络社会运动 历史唯物主义
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