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Detrital zircon U-Pb-he double dating: A method of quantifying long- and short-term exhumation rates in collisional orogens

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Science China Earth Sciences 2014年第11期57卷 2702-2711页

作者： Christina Yan WANG Ian h.CAMPBELL Peter W.REINERS Charlotte M.ALLEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences Research School of Earth Sciences The Australian National UniversityCanberra ACT 0200 Australia Department of Geosciences University of ArizonaTucson AZ 85721 USA

A U-Pb-he double-dating method is applied to detrital zircons with core-rim structure from the Ganges River in order to de- termine average short and long-term exhumation rates for the himalayas. Long-term rates are calculated from the U/Pb ages of metamorphic rims of the grains that formed during the himalayan orogeny and their crystallization temperatures, which are calculated from the Ti-in-zircon thermometer. Short-term rates are calculated from （U-Th）/he ages of the grains with appro- priate closure temperatures. The results show that short-term rates for the himalayas, which range from 0.70 ± 0.09 to 2.67 ± 0.40 km/Myr and average 1.75 ± 0.59 （1δ） km/Myr, are higher and more varied than the long-term rates, which range from 0.84 ±0.16 to 1.85 ± 0.35 km/Myr and average 1.26 ±0.25 （let） km/Myr. The differences between the long-term and short-term rates can be attributed to continuous exhumation of the host rocks in different mechanisms in continental collision orogen. The U/Pb ages of 44.0 ± 3.7 to 18.3 ±0.5 Ma for the zircon rims indicate a protracted episode of -：25 Myr for regional metamorphism of the host rocks at deeper crust, whereas the （U-Th）/he ages of 42.2 ± 1.8 to 1.3 ± 0.2 Ma for the zircon grains represent a protracted period of -40 Myr for exposure of the host rocks to shallower crustal level. In particular, the oldest （U-Th）/he ages of the zircon grains are close to the oldest U/Pb ages for the rims, indicating that some parcels of the rocks that contain zircons were rapidly exhumed from deep to shallow levels in the stage of collisional orogeny. On the other hand, some parcels of the rocks may have been carried upwards by thrust faults in the post-collisional stage. The parcels could be carried upwards by the thrust faults that steepen as they near the surface, or by transient movement faults so that areas of rapid exhu- mation became areas of slow exhumation and visa versa on a time scale of a few Myr in order to maintain the continuous ex- huma

关键词： zircon U-Pb-he double-dating method himalayas exhumation rate collisional orogen

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A long time span relativistic precession model of the Earth

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Research in Astronomy and Astrophysics 2015年第4期15卷 583-596页

作者： Kai Tang Michael h.Soffel Jin-he Tao Wen-Biao han Zheng-hong Tang Shanghai Astronomical Observatory Chinese Academy of Sciences University of Chinese Academy of Sciences Lohrmann Observatory Dresden Technical University

A numerical solution to the Earth＇s precession in a relativistic framework for a long time span is presented here. We obtain the motion of the solar system in the Barycentric Celestial Reference System by numerical integration with a symplectic in- tegrator. Special Newtonian corrections accounting for tidal dissipation are included in the force model. The part representing Earth＇s rotation is calculated in the Geocentric Celestial Reference System by integrating the post-Newtonian equations of motion published by Klioner et al. All the main relativistic effects are included following Klioner et al. In particular, we consider several relativistic reference systems with cor- responding time scales, scaled constants and parameters. Approximate expressions for Earth＇s precession in the interval ~1 Myr around J2000.0 are provided. In the interval 4-2000 years around J2000.0, the difference compared to the P03 precession theory is only several arcseconds and the results are consistent with other long-term precession theories.

关键词： astrometry -- ephemeris -- post-Newtonian

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Numerical Analysis of Non-Fourier heat Transfer in a Solid Cylinder with Dual-Phase-Lag Phenomenon

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 399-414页

作者： M.h.Ghasemi S.hoseinzadeh P.S.heyns D.N.Wilke Department of Mechanical Engineering West Tehran BranchIslamic Azad UniversityTehranIran Centre for Asset Integrity Management Department of Mechanical and Aeronautical EngineeringUniversity of PretoriaPretoriaSouth Africa Young Researchers and Elite Club West Tehran BranchIslamic Azad UniversityTehranIran

In this study,transient non-Fourier heat transfer in a solid cylinder is analytically solved based on dual-phase-lag for constant axial heat flux *** equations for the model are expressed in two-dimensional cylindrical coordinates;the equations are nondimensionalized and exact solution for the equations is presented by using the separation of variable *** showed that the dual-phase-lag model requires less time to meet the steady temperature compared with single-phase-lag *** the contrary,thermal wave diffusion speed for the dual-phase-lag model is greater than the single-phase-lag *** the effect of relaxation time in dual-phase-lag model has been taken on consideration.

关键词： Exact solution non-Fourier heat transfer dual-phase-lag cylindrical coordinate

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Biochemical mechanisms in drug-induced liver injury:Certainties and doubts

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World Journal of Gastroenterology 2009年第39期15卷 4865-4876页

作者： Ignazio Grattagliano Leonilde Bonfrate Catia V Diogo helen h Wang David Qh Wang Piero Portincasa Clinica Medica "A.Murri" Dipartimento di Medicina Interna e Medicina PubblicaUniversity of Bari Medical School Department of Zoology Center for Neurosciences and Cell BiologyUniversity of Coimbra Department of Medicine Liver Center and Gastroenterology DivisionBeth Israel Deaconess Medical CenterHarvard Medical School and Harvard Digestive Diseases Center

Drug-induced liver injury is a significant and still unresolved clinical problem. Limitations to knowledge about the mechanisms of toxicity render incomplete the detection of hepatotoxic potential during preclinical development. Several xenobiotics are lipophilic substances and their transformation into hydrophilic compounds by the cytochrome P-450 system results in production of toxic metabolites. Aging, preexisting liver disease, enzyme induction or inhibition, genetic variances, local 02 supply and, above all, the intrinsic molecular properties of the drug may affect this process. Necrotic death follows antioxidant consumption and oxidation of intracellular proteins, which determine increased permeability of mitochondrial membranes, loss of potential, decreased ATP synthesis, inhibition of Ca^2＋-dependent ATPase, reduced capability to sequester Ca^2＋ within mitochondria, and membrane bleb formation. Conversely, activation of nucleases and energetic participation of mitochondria are the main intracellular mechanisms that lead to apoptosis. Non-parenchymal hepatic cells are inducers of hepatocellular injury and targets for damage. Activation of the immune system promotes idiosyncratic reactions that result in hepatic necrosis or cholestasis, in which different hLA genotypes might play a major role. This review focuses on current knowledge of the mechanisms of drug-induced liver injury and recent advances on newly discovered mechanisms of liver damage. Future perspectives including new frontiers for research are discussed.

关键词： Adverse effects Apoptosis Drug toxicity Liver diseases Microsomes Mitochondria Necrosis

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Application of seminal germ cell morphology and semen biochemistry in the diagnosis and management of azoospermic subjects

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Asian Journal of Andrology 2001年第1期3卷 55-62页

作者： Somnath Roy A.Banerjee h.C.Pandey G.Singh G.L.Kumari National Institute of health and Family Welfare (NIhFW) New Delhi-110067 India Reproductive Health Foundation(RHF) New Delhi IndiaNational Institute of Health and Family Welfare (NIHFW) New Delhi-110067 IndiaNational Institute of Health and Family Welfare (NIHFW) New Delhi-110067 IndiaNational Institute of Health and Family Welfare (NIHFW) New Delhi-110067 IndiaReproductive Health Foundation (RHF) New Delhi India

Aim: To evaluate whether the study of seminal germ cell morphology (SGCM) and semen biochemistry could befruitfully utilized for the diagnosis and management of azoospermic subjects. Methods: In the semen, mature andimmature germ cells are contributed by the testes, 70% of glycerylphosphoryl choline (GPC) by the epididymis, fruc-tose mostly or solely by the seminal vesicles and acid phosphate (ACP) by the prostate. In 16 normal volunteers, 12vasectomized subjects and 186 azoospennic subjects, these parameters have been studied and the data have been ana-lyzed. Results: Both mature and immature germ cells are absent in the semen of vasectomized subjects as well as inobstructive azoospennia; GPC level is also significantly decreased in both these groups. In cases with non-obstructiveazoospermia immature germ cells are present and seminal GPC, ACP and fructose levels are normal. The diagnosis ofobstructive and non-obstructive azoospermia based on these parameters correlated well with 'correct' testicular biopsyfindings. In some cases of azoospermia due to hypospermatogenesis or spermatogenic developmental arrest, the SGCMstudies were very helpful in objectively monitoring the response of the germinal tissue to specific treaunents. Conclu-sion: SGCM and semen biochemical parameters are very valuable non-invasive markers for differentiating obstructivefrom non-obstructive azoospermia. The SGCM findings serve as a dependable non-invasive testicular marker with highpredictive value. (Asian J Androl 2001 Mar; 3: 55-62)

关键词： azoospermia semen biochemistry germ cells intracytoplasmic sperm injection

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Some Physiological Responses of Chinese Iris to Salt Stress

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Pedosphere 2008年第4期18卷 454-463页

作者： BAI Wen-Bo LI Pin-Fang LI Bao-Guo h. FUJIYAMA FAN Fen-Cheng College of Resources and Environmental Sciences China Agricultural University Key Laboratory of Plant-Soil Interactions Ministry of Education Beijing 100094 （China） Faculty of Agriculture Tottori University Tottori 680-8553 （Japan） Beijing Oasis Technology Development Co. Ltd. Beijing 100094 （China）

Chinese iris （Iris lactea Pall. var. chinensis （Fisch） Koidz.）, a robust iridaceous plant, is widespread in arid and semiarid regions with high salinity. however, the mechanism of its salt tolerance is not well understood. In this study, plant growth, water status, content and distribution of inorganic ions, cell membrane permeability, and proline content of I. laetea under salt stress were investigated using nutrient solutions with six NaCl concentrations ranging from 0 to 350 mmol L^-1. The results indicated that the biomass, height, fresh weight, K^＋ content, and K^＋/Na^＋ and Ca^2＋/Na^＋ ratios decreased with increasing NaCl stress, whereas plant water deficit and contents of Na^＋ and Cl- increased with increasing NaCl stress. In all salt treatments, water deficit of shoots was found to be higher than that of roots and had a positive correlation with salt concentration. When the NaCl concentration was less than 280 mmol L^-1, the ion absorption selectivity ratio and the transportation selectivity ratio sharply increased with increasing NaCl stress. Under medium salt stress, I. lactea exhibited a strong K^＋ selective absorption and the transportation of K^＋ from roots to shoots increased, whereas Na^＋ was not transported and was mostly retained in roots. The plants were able to maintain osmotic adjustment through the accumulation of Na^＋, Cl-, and proline. On the basis of its biomass production under salt stress, I. lactea could be considered as a facultative halophyte.

关键词： inorganic ion Iris lactea Pall. var. chinensis (Fisch) Koidz. NaCl stress osmotic adjustment

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Contrasting microscopic interactions determine the properties of water/methanol solutions

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Frontiers of physics 2018年第1期13卷 51-56页

作者： Carmelo Corsaro Francesco Mallamace Sebastiano Vasi Sow-hsin Chen h. Eugene Stanley Domenico Mallamace CNR-IPCF Messina Istituto per i Processi Chimico-Fisici Viale F. Stagno D'Alcontres 37 98158 Messina Italy Dipartimento MIFT Sezione di Fisica Universita di Messina Viale F. Stagno D'Alcontres 31 98166 Messina Italy Department of Nuclear Science and Engineering Massachusetts Institute of Technology Cambridge MA 02139 USA Center for Polymer Studies and Department of Physics Boston University Boston MA 02215 USA Consorzio interuniversitario per lo sviluppo dei Sistemi a Grande Interfase - CSGI Via della Lastruccia 3 50019 Sesto Fiorentino Firenze Italy

herein we study the different microscopic interactions occurring in water/methanol solutions at dif- ferent methanol molar fractions, using NMR spctroscopy. Temperature was found to determine which interaction dominates. It was found that the mixing between water and methanol is non-ideal because of the presence of interactions like hydrophobicity and hydrophilicity. These results indicate that the competition between hydrophilic and hydrophobic interactions is different in different thermal regions, and that the physical properties of the solution are determined by the character of the solution itself, which in turn depends on the mole fraction of methanol and on the temperature.

关键词： aqueous solutions hydrophobicity NMR hydrophilicity

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The corpus cavernosum after treatment with dutasteride or finasteride： a histomorphometric study in a benign prostatic hyperplasia rodent model

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Asian Journal of Andrology 2018年第5期20卷 505-510页

作者： Marcello h A Da Silva Waldemar S Costa Francisco J B Sampaio Diogo B De Souza Urogenital Research Unit Rio de Janeiro State University Rio de Janeiro RJ 20551-030 Brazil

Erectile dysfunction is a common side effect of finasteride and dutasteride treatments. The objective of this study was to investigate the structural changes in the penis using a benign prostatic hyperplasia （BPh） rodent model treated with dutasteride or finasteride. Sixty male rats were divided into the following groups： C, untreated control rats; C ＋ D, control rats receiving dutasteride; C ＋ F, control rats receiving finasteride; h, untreated spontaneously hypertensive rats （ShRs）; h ＋ D, ShRs treated with dutasteride; and h ＋ F, ShRs treated with finasteride. Treatments were performed for 40 days, and penises were collected immediately thereafter. The organs were analyzed using histomorphometric methods to determine the cross-sectional penile area, as well as the surface density （Sv） of smooth muscle fibers, connective tissue, elastic system fibers, and sinusoidal spaces of the corpus cavernosum. The results were compared using a one-way ANOVA with Bonferroni＇s posttest. Groups C ＋ D and C ＋ F had a significantly smaller penile cross-sectional area, but more elastic system fiber Sv compared to Group C. Group C ＋ D showed less smooth muscle Sv, and Group h showed more connective tissue but a smaller sinusoidal space Sv in the corpus cavernosum compared to Group C. Groups h ＋ D and h ＋ F had less smooth muscle Sv than Group h. Group h ＋ D also had more connective tissue and elastic system fiber Sv than Group h. Both dutasteride and finasteride promoted penile modifications in the control rat penis, although this affect was ~reater in Group h animals. In this rodent model, dutasteride was the drug that most affected the corpus cavernosum.

关键词： animal models benign prostatic hyperplasia dutasteride erectile dysfunction finasteride penis

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New multi protein patterns differentiate liver fibrosis stages and hepatocellular carcinoma in chronic hepatitis C serum samples

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World Journal of Gastroenterology 2006年第47期12卷 7604-7612页

作者： Thomas Gbel Sonja Vorderwülbecke Katarzyna hauck holger Fey Dieter hussinger Andreas Erhardt Klinik für Gastroenterologie Hepatologie und InfektiologieHeinrich-Heine-UniversitatDusseldorfMoorenstr.eD-40225 DusseldorfGermany Ciphergen Biosystems Neuendorfstr.24aD-16761 Hennigsdorf bei berlinGermany

AIM： To identify a multi serum protein pattern as well as single protein markers using surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry （SELDI-TOF-MS） for detection and differentiation of liver fibrosis （F1-F2）, liver cirrhosis （F4） and hepatocellular carcinoma （hCC） in patients with chronic hepatitis C virus （hCV）. METhODS： Serum samples of 39 patients with F1/F2 fibrosis, 44 patients with F4 fibrosis, 34 patients with hCC were applied to CM10 arrays and analyzed using the SELDI-TOF ProteinChip System （PBS-Ⅱc; Ciphergen Biosystems） after anion-exchange fractionation. All patients had chronic hepatitis C and histologically confirmed fibrosis stage/hCC. Data were analyzed for protein patterns by multivariate statistical techniques and artificial neural networks. RESULTS： A 4 peptide/protein multimarker panel （7486, 12843, 44293 and 53598 Da） correctly identified hCCs with a sensitivity of 100% and specificity of 85% in a two way-comparison of hCV-cirrhosis versus hCV-hCC training samples （AUROC 0.943）. Sensitivity and specificity for identification of hCC were 68% and 80% for random test samples. Cirrhotic patients could be discriminated against patients with F1 or F2 fibrosis using a 5 peptide/protein multimarker pattern （2873, 6646, 7775, 10525 and 67867 Da） with a specificity of 100% and a sensitivity of 85% in training samples （AUROC 0.976） and a sensitivity and specificity of 80% and 67% for random test samples. Combination of the biomarker classifiers with APR/score and alfa-fetopotein （AFP） improved the diagnostic performance. The 6646 Da marker protein for liver fibrosis was identified as apolipoprotein C-I. CONCLUSION： SELDI-TOF-MS technology combined with protein pattern analysis seems a valuable approach for the identification of liver cirrhosis and hepatocellular carcinoma in patients with chronic hepatitis C. host probably a combination of different serum markers will help to identify liver cirrhosis and early-stage hep

关键词： hepatocellular carcinoma hepatitis C virus Apolipoprotein C- I Proteomics Surface-enhanced laser desorption/ionisation

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Engineering properties of the Bukit Timah Granitic residual soil in Singapore

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Underground Space 2019年第2期4卷 98-108页

作者： W.G.Zhang R.h.Zhang L.han A.T.C.Goh Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqingChina National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400045China Key Laboratory of Rock Mechanics in hydraulic Structural Engineering Ministry of EducationWuhan 430072China School of Civil Engineering Chongqing UniversityChongqingChina School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore

Extensive site investigations were conducted prior to the construction of a Mass Rapid Transit project in Singapore that was predominantly in the Bukit Timah Granite(BTG)formation residual *** paper evaluates the engineering properties of the BTG formation residual soil based on data from 208 site investigation boreholes from four different *** on the results from 2481 conventional laboratory tests and 1192 in-situ tests,this paper summarizes the engineering properties of the highly variable BTG residual soil,including conventional composition analysis,index and hydraulic properties,and strength and deformation parameters required for geotechnical analysis and *** on these results,the BTG formation is found to be quite *** the degree of weathering decreases with depth from the top of the formation,the BTG residual soil becomes sandier,with reduced silt and clay *** coefficient of permeability and the compression index of the BTG residual soil vary *** addition,the empirical equations relating the shear strength(index)to the standard penetration test(SPT)-N,as well as the equations and charts for determining stiffness,are *** findings,together with the proposed equations or charts,can be used for design guidance of similar projects related to granitic residual soils in Singapore.

关键词： Bukit Timah Granite Residual soil Shear strength Stiffness Laboratory testing In-situ testing

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