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Zircon U-pb-Hf constraints from gongga Shan granites on young crustal melting in eastern Tibet

geoscience Frontiers 2019年第3期10卷 885-894页

作者： Nick M.W.Roberts Michael p.Searle NERC Isotope geosciences Laboratory British Geological Survey Environment Science Centre Department of Earth Sciences University of Oxford

The gongga Shan batholith is a complex granitoid batholith on the eastern margin of the Tibetan plateau with a long history of magmatism spanning from the Triassic to the pliocene. Late Miocene-pliocene units are the youngest exposed crustal melts within the entire Asian plate of the Tibetan ***, we present in-situ zircon Hf isotope constraints on their magmatic source, to aid the understanding of how these young melts were formed and how they were exhumed to the surface. Hf isotope signatures of Eocene to pliocene zircon rims(ε_(Hf)(t)=-4 to +4), interpreted to have grown during localised crustal melting, are indicative of melting of a Neoproterozoic source region, equivalent to the nearby exposed Kangding Complex. Therefore, we suggest that Neoproterozoic crust underlies this region of the Songpan-ganze terrane, and sourced the intrusive granites that form the gongga Shan batholith. Localised young melting of Neoproterozoic lower or middle crust requires localised melt-fertile lithologies. We suggest that such melts may be equivalent to seismic and magnetotelluric low-velocity and high-conductivity zones or "bright spots" imaged across much of the Tibetan plateau. The lack of widespread exposed melts this age is due either to the lack of melt-fertile rocks in the middle crust, the very low erosion level of the Tibetan plateau, or to a lack of mechanism for exhuming such melts. For gongga Shan, where some melting is younger than nearby thermochronological ages of low temperature cooling, the exact process and timing of exhumation remains enigmatic, but their location away from the Xianshuihe fault precludes the fault acting as a conduit for the young melts. We suggest that underthrusting of dry granulites of the lower Indian crust(Archaean shield) this far northeast is a plausible mechanism to explain the uplift and exhumation of the eastern Tibetan plateau.

关键词： Tibet Himalaya Hf isotopes Zircon Crustal melting

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Arbuscular mycorrhizal fungal association in Asteraceae plants growing in the arid lands of Saudi Arabia

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Journal of Arid Land 2015年第5期7卷 676-686页

作者： partha p DHAR Abdul A AL-QARAWI Mohammed A U MRIDHA plant production Department College of Food and Agricultural Sciences King Saud University

The present research was undertaken to explor the possibility of arbuscular mycorrhizal （AM） associa- tion with Asteraceae plants in the arid lands of Saudi Arabia （AI-ghat, Buraydah, Thumamah and Huraymila）. AM fungal colonization in the roots, spore numbers in the rhizosphere soil, fungal species diversity and correlation between AM properties and soil properties were determined. The highest colonization was in Conyza bonariensis （65%） from AI-ghat, Anthemis cotula （52%） from Buraydah and C. bonariensis （53%） from Thumamah. The lowest was in Vernonia schimperi （41%） from AI-ghat, pulicaria undulata （25%） from Buraydah, Acanthospermum his- pidum （34%） from Thumamah, Asteriscus graveolens （22%） and V. schimperi （22%） from Huraymila. Vesicular and arbuscular colonization were also presented in all plant species examined. The number of spores were 112-207 in AI-ghat, 113-133 in Buraydah, 87-148 in Thumamah and 107-158 in Huraymila. Funneliformis mosseae, glomus etunicatum, g. fasciculatum and g aggregatum were identified. Relative frequency of AM fungal species varied widely and was irrespective of location and plant species. Diversity index varied with the rhizosphere soils of dif- ferent plant species at various locations. Soil properties varied with locations and no distinct correlations were ob- served among the soil properties, root colonization and the number of spores. The results of the present study specified the association of AM fungi in different plants of Asteraceae and its significance in the ecological func- tioning of annual plants in the punitive environments of the rangelands in Saudi Arabia.

关键词： arbuscular mycorrhizal fungi arid land Asteraceae biodiversity colonization Saudi Arabia

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L-fuzzy Roughness of n-ary polygroups

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Acta Mathematica Sinica,English Series 2011年第1期27卷 97-118页

作者： Yun Qiang YIN Jian Ming ZHAN p. CORSINI School of Mathematzcs and Information Sciences East China Institute of Technology Fuzhou 344000 P. R. China Department of Mathematics Hubei University for Nationalities Enshi 445000 P. R. China Department of Biology and Agro-Industrial Economy Via delle Seienze 208 33100 Udine Italy

In this paper, we consider the relations among L-fuzzy sets, rough sets and n-ary polygroup theory. Some properties of （normal） TL-fuzzy n-ary subpolygroups of an n-ary polygroup are first obtained. Using the concept of L-fuzzy sets, the notion of ~）-lower and T-upper L-fuzzy rough approximation operators with respect to an L-fuzzy set is introduced and some related properties are presented. Then a new algebraic structure called （normal） TL-fuzzy rough n-ary polygroup is defined and investigated. Also, the （strong） homomorphism of θ-lower and T-upper L-fuzzy rough approximation operators is studied.

关键词： n-Ary polygroups (normal) TL-fuzzy n-ary polygroups θ-lower L-fuzzy rough approxi-mation T-upper L-fuzzy rough approximation (strong) homomorphism

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Cellular reprogramming in farm animals： an overview of ipSC generation in the mammalian farm animal species

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Journal of Animal Science and Biotechnology 2016年第4期7卷 459-467页

作者： J. Ogorevc S. Orehek p. DovcC Department of Animal Science Biotechnical Faculty University of LjubljanaDomzale Slovenia

Establishment of embryonic stem cell （ESC） lines has been successful in mouse and human, but not in farm animals. Development of direct reprogramming technology offers an alternative approach for generation of pluripotent stem cells, applicable also in farm animals. Induced pluripotent stem cells （ipSCs） represent practically limitless, ethically acceptable, individuum-specific source of pluripotent cells that can be generated from different types of somatic cells, ipSCs can differentiate to all cell types of an organism＇s body and have a tremendous potential for numerous applications in medicine, agriculture, and biotechnology. However, molecular mechanisms behind the reprogramming process remain largely unknown and hamper generation of bona fide ipSCs and their use in human clinical practice. Large animal models are essential to expand the knowledge obtained on rodents and facilitate development and validation of transplantation therapies in preclinical studies. Additionally, transgenic animals with special traits could be generated from genetically modified pluripotent cells, using advanced reproduction techniques. Despite their applicative potential, it seems that ipSCs in farm animals haven＇t received the deserved attention. The aim of this review was to provide a systematic overview on ipSC generation in the most important mammalian farm animal species （cattle, pig, horse, sheep, goat, and rabbit）, compare protein sequence similarity of pluripotency-related transcription factors in different species, and discuss potential uses of farm animal ipSCs. Literature mining revealed 32 studies, describing ipSC generation in pig （13 studies）, cattle （5） horse （5）, sheep （4）, goat （3）, and rabbit （2） that are summarized in a concise, tabular format.

关键词： Cellular reprogramming Farm animals Induced pluripotent stem cells pluripotency

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physical properties of lunar craters

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Research in Astronomy and Astrophysics 2017年第3期17卷 23-38页

作者： Maitri p. Joshi Kushal R Bhatt Rajmal Jain Shri Maneklal M.patel Institute of Sciences and Research Kadi Sarva VishwavidhyalayaGandhinagar-382015India

The surface of the Moon is highly cratered due to impacts of meteorites, asteroids, comets and other celestial objects. The origin, size, structure, age and composition vary among craters. We study a total of 339 craters observed by the Lunar Reconnaissance Orbiter Camera （LROC）. Out of these 339 craters, 214 craters are known （named craters included in the IAU gazetteer of planetary Nomenclature） and 125 craters are unknown （craters that are not named and objects that are absent in the IAU gazetteer）. We employ images taken by LROC at the North and South poles and near side of the Moon. We report for the first time the study of unknown craters, while we also review the study of known craters conducted earlier by previous researchers. Our study is focused on measurements of diameter, depth, latitude and longitude of each crater for both known and unknown craters. The diameter measurements are based on considering the Moon to be a spherical body. The LROC website also provides a plot which enables us to measure the depth and diameter. We found that out of 214 known craters, 161 craters follow a linear relationship between depth （d） and diameter （D）, but 53 craters do not follow this linear relationship. We study physical dimensions of these 53 craters and found that either the depth does not change significantly with diameter or the depths are extremely high relative to diameter （conical）. Similarly, out of 125 unknown craters, 78 craters follow the linear relationship between depth （d） and diameter （D） but 47 craters do not follow the linear relationship. We propose that the craters following the scaling law of depth and diameter, also popularly known as the linear relationship between d and D, are formed by the impact of meteorites having heavy metals with larger dimension, while those with larger diameter but less depth are formed by meteorites/celestial objects having low density material but larger diameter. The craters with very high depth and with very small d

关键词： Moon meteorites meteors meteoroids- planets and satellites: surfaces

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MicroRNA regulation of innate immune responses in epithelial cells

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Cellular & Molecular Immunology 2011年第5期8卷 371-379页

作者： Rui Zhou Steven p O’Hara Xian-Ming Chen Department of Microbiology and Immunology Creighton University School of MedicineOmahaNEUSA Division of gastroenterology and Hepatology Department of Internal MedicineMayo Clinic College of MedicineRochesterMNUSA

Mucosal surface epithelial cells are equipped with several defense mechanisms that guard against *** studies indicate that microRNAs(miRNAs)mediate post-transcriptional gene suppression and may be a critical component of the complex regulatory networks in epithelial immune *** of miRNA genes in epithelial cells can be elaborately controlled through pathogen recognition receptors,such as Toll-like receptors(TLRs),and associated nuclear factor kappaB(NF-kB)and mitogen-activated protein kinase(MApK)pathways,and ultimately nuclear transcription factor associated-transactivation and *** of these intracellular signaling pathways may also modulate the process of miRNA ***,miRNAs may modulate epithelial immune responses at every step of the innate immune network,including production and release of cytokines/chemokines,expression of adhesion and costimulatory molecules,shuttling of miRNAs through release of exosomes and feedback regulation of immune ***,miRNAs act as critical regulators to the fine-tuning of epithelial immune responses.

关键词： epithelial cells immune responses miRNAs posttranscriptional regulation TLRs

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Microstructural observations on the terminal penetration of long rod projectile

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Defence Technology（防务技术） 2017年第6期13卷 413-421页

作者： Krushna Kumbhar p.ponguru Senthil A.K.gogia Armour Design and Development Division Defence Metallurgical Research LaboratoryHyderabad 500058India

present study focuses on the terminal penetration of tungsten heavy alloy(WHA) long rod penetrator impacted against armour steel at an impact velocity of 1600 m/s. The residual penetrator and armour steel target recovered after the ballistic test have been characterized using optical microscope, scanning electron microscope(SEM) and electron probe micro analyzer(EpMA). Metallurgical changes in target steel and WHA remnant have been analysed. Large shear stresses and shear localization have resulted in local failure and formation of erosion products. Severe plastic deformation acts as precursor for formation of adiabatic shear band(ASB) induced cracks in target steel. Recovered WHA penetrator remnant also exhibits severe plastic deformation forming localized shear bands, ASB induced cracks and shock induced cracks.

关键词： Long rod projectile Terminal penetration Shear localization Adiabatic shear band Tungsten heavy alloy Armour steel

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Thermoelectric converter based on metal-dielectric-semiconductor-metal structures for cooling processors

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Journal of Advanced Dielectrics 2020年第1期10卷 42-47页

作者： g.Ya.Karapetyan I.A.parinov g.parchiy I.I.Vorovich Institute of Mathematics Mechanics and Computer Sciences Southern Federal University Rostov-on-Don 344090 Russia

A thermoelectric transducer based on MDSM structures of the field-effect transistor(FET)type is proposed,in which the thermal energy of the environment is converted into electrical *** use a new principle of converting thermal energy into electrical *** show that with the help of such a converter,it is possible to dramatically increase the efficiency of processors due to the heat generated by the processor is converted by this converter again into electricity that transfers to the processor.

关键词： Crystal growth thermoelectric converter field-effect transistor metal-dielectric-semiconductor-metal(MDSM)structure processor

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Development of Water Quality Index (WQI) model for the groundwater in Tirupur district, South India

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Chinese Journal Of geochemistry 2013年第3期32卷 261-268页

作者： p.J.Sajil Kumar E.J.James Water Institute Karunya University

groundwater quality of the Tiruppur district in Tamil Nadu was investigated in this study to develop a Water Quality Index (WQI) model. Hydrochemical parameters showed tremendous variation in certain location over the seasons. Ionic chemistry of groundwater suggested that textile industries and rock-water interaction are major threats to the water quality. Analysis of Na and Ca concentration indicates that direct as well as the inverse cation exchange controls the natural cation chemistry. NO3 concentration shows that the pre-monsoon samples were affected by the fertilizer usage in agricultural fields. Na-Cl type of the water was dominant throughout the study area except few locations. WQI showed that 55% of the pre-monsoon samples and the 47% of the post monsoon samples were classified as poor/very poor/unsuitable for drinking category. Leaching of the textile waste and their transport to the downstream was well observed during the post-monsoon season. The specific contribution of river Noyyal in the transport of the solutes to the discharge zones was proved by the hydrochemistry of the samples.

关键词：地下水模型水质指数印度水岩相互作用离子化学 O3浓度纺织废料化学样品

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Evaluation of alternative conceptual models for groundwater modelling

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geoscience Frontiers 2017年第3期8卷 437-443页

作者： Yangxiao Zhou H.M.p.S.D.Herath UNESCO-IHE Institute for Water Education

This study evaluates the alternative conceptual models for groundwater modelling. A true model was created with a synthetic alluvial fan-plain hydrogeological framework. Various alternative conceptual models were evaluated for groundwater flow simulations. The first alternative model is a single aquifer layer model; the second alternative model is a 3-layer aquifer model; and the third model is a B-layer model consisting of 3 aquifers separated by 2 aquitards. All models could fit very well to the observa- tions with optimized values of hydraulic conductivities. However, the single aquifer layer model can only compute water balance components with good accuracy. The 3-layer aquifer model can be used for water balance computation and groundwater head simulation with small errors. The 5-layer model is capable of simulating water budget, groundwater head distribution and travel times with high accuracy. Multi- model analysis found only the 3rd alternative model superior.

关键词： Alternative conceptual modelsMulti-model analysisWater budgetTravel time

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