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Subsidence history and forming mechanism of anomalous tectonic subsidence in the Bozhong depression, Bohaiwan basin

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Science China Earth Sciences 2007年第9期50卷 1310-1318页

作者： müLLER R. Dietmar School of Geosciences University of Sydney Sydney NSW 2006 Australia

The Bozhong depression of the Bohaiwan basin belongs to a family of extensional basins in East China, but is quite different from other parts of the basin. The Cenozoic subsidence of the depression is controlled by a combination of lithospheric thinning and polycyclic strike-slip movements. Three episodic rifts have been identified, i.e. Paleocence-early Eocene, middle-late Eocene and Oligocene age. The depression underwent syn-rift and post-rift stages, but two episodic dextral movement events of the strike-slip faults modify the subsidence of the Bozhong depression since the Oligocene. The early dextral movement of the Tan-Lu fault associated with crustal extension resulted in accelerated subsidence during the time of deposition of the Dongying Formation with a maximum thickness of 4000 m. A late reactivation of dextral movement of the Tan-Lu fault began in late miocene (about 12 ma), which resulted in the intense subsidence of minghuazhen Formation and Quaternary. in addition, dynamic mantle convection-driven topography also accelerated the post-rift anomalous subsidence since the miocene (24.6 ma). Our results indicate that the primary control on rapid subsidence both during the rift and post-rift stages in the Bozhong depression originates from a combination of multiple episodic crustal extension and polycyclic dextral movements of strike-slip faults, and dynamic topography.

关键词： tectonic subsidence strike-slip dynamic topography Bozhong depression Bohaiwan basin

Development of Caenorhabditis elegans pharynx,with emphasis on its nervous system

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Acta Pharmacologica Sinica 2005年第4期26卷 396-404页

作者： marc PiLON Catarina m RCK Lundberg Laboratory Chalmers University G teborg S-405 30 Sweden Lundberg Laboratory Chalmers University G teborg S-405 30 Sweden

The Caenorhabditis elegans pharynx is a neuromuscular tube of which the func-tion is to pump and crush bacteria,and inject them into the *** 80-cellpharynx develops via the morphogenesis and differentiation of the ceils that com-pose its semi-spherical primordiurn,and requires the activity of several evolution-arily conserved genes,such as pha-4 (the homolog to the Drosophilaforkheadand vertebrate FoxA),ceh-22 (the homolog to the Drosophila tinman and verte-brate Nkx2.5),and pha-2 (the homolog to the vertebrate Hex).There are 20 neu-rons in the pharynx,each with a reproducible unique *** analysis of axon guidance in the pharynx indicates that some axon trajec-tories are in part established without growth cones,whereas other parts necessi-tate growth cone function and *** we provide an overview of thedevelopmental genetics of the Caenorhabditis elegans pharynx,with an empha-sis on its nervous system.

关键词： Caenorhabditis elegans pharynx axon growth cones morphogenesis heart

B→0^+(1^+)+ missing energy in unparticle physics

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Chinese Physics C 2009年第5期33卷 332-339页

作者： m.Jamil Aslam 吕才典 institute of High Energy Physics CAS Department of Physics COMSATS Institute of Information Technology School of Physics and Technology Nanjing Normal University

We examine the effects of an unparticle U as a possible source of missing energy in the p-wave decays of a B meson. The dependence of the differential branching ratio on the K0^＊（K1） - meson＇s energy is discussed in the presence of scalar and vector unparticle operators and significant deviation from the standard model value is found after addition of these operators. Finally, we have shown the dependence of the branching ratio for the above-mentioned decays on the parameters of unparticle stuff like effective couplings, cutoff scale Au and the scale dimensions du.

关键词： unparticle missing energy B physics

Sex determination in mammalian germ cells

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Asian Journal of Andrology 2015年第3期17卷 427-432页

作者： Cassy m Spiller Josephine Bowles institute for molecular Bioscience The University of Queens/and Brisbane QLD 4072 Australia

Germ cells are the precursors of the sperm and oocytes and hence are critical for survival of the species. in mammals, they are specified during fetal life, migrate to the developing gonads and then undergo a critical period during which they are instructed, by the soma, to adopt the appropriate sexual fate. in a fetal ovary, germ cells enter meiosis and commit to oogenesis, whereas in a fetal testis, they avoid entry into meiosis and instead undergo mitotic arrest and mature toward spermatogenesis. Here, we discuss what we know so far about the regulation of sex-specific differentiation of germ cells, considering extrinsic molecular cues produced by somatic cells, as well as critical intrinsic changes within the germ cells. This review focuses almost exclusively on our understanding of these events in the mouse model.

关键词： germ cells meiosis oocytes sex determination processes spermatozoa

Helically symmetric equilibria for some ideal and resistive mHD plasmas with incompressible flows

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Applied mathematics(A Journal of Chinese Universities) 2023年第2期38卷 192-209页

作者： S.m.moawad O.H.El-Kalaawy H.m.Shaker mathematics and Computer Science Department Faculty of ScienceBeni-Suef UniversityBeni-SuefEgypt Future High institute of Engineering in Fyoum Ministry of High EducationFyoumEgypt

in this paper, the problem of finding exact solutions to the magnetohydrodynamic(mHD) equations in the presence of incompressible mass flows with helical symmetry is considered. For ideal flows, a similarity reduction method is used to obtain exact solutions for several mHD flows with nonlinear variable mach number. For resistive flows parallel to a magnetic field, the governing equilibrium equation is derived. The mHD equilibrium state of a helically symmetric incompressible flow is governed by a second-order elliptic partial differential equation(PDE) for the helical magnetic flux function. Exact solutions for the latter equation are obtained. Also, the equilibrium equations of a gravitating plasma with incompressible flow are derived.

关键词： magnetohydrodynamics helical symmetry resistivity incompressible ows exact equilibria

Storage stability of dried tomato slice

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international Journal of Agricultural and Biological Engineering 2013年第4期6卷 104-110页

作者： Shittu S K isiaka m Department of Agricultural Engineering Bayero UniversityKanoNigeria Department of Agricultural Engineering Ahmadu Bello UniversityZariaNigeria

Unlike fresh farm produce,processed fruits and vegetables such as sun dried tomatoes can be categorized as ambient temperature shelf stable ***,large quantities of these products yet easily go bad most especially when the appropriate conditions for their storage are not *** minimize these losses,it is important to know and exploit the optimum environmental conditions and moisture content range for the storage of the *** present study through systematic theoretical assertions employed by other researchers on other crops seeks to establish the storage stability of dried tomato slice at three probable temperatures of 10,30 and 45°*** showed that in this temperature range,upper limit moisture content varied between 6%-7.5%and 6.5%-8.3%*** adsorption and desorption,*** corresponding lower limit moisture contents varied between 4.29%-5.52%and 5.15%-6.29%*** order to minimize moisture migration into or out of dried tomato slice during storage,the study revealed that the product should be stored within 29%-62%relative humidity.

关键词： dried tomato storage stability moisture content humidity temperature

The boring billion? - Lid tectonics, continental growth and environmental change associated with the Columbia supercontinent

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Geoscience Frontiers 2013年第6期4卷 681-691页

作者： nick m.W.Roberts NERC isotope Geosciences Laboratory British Geological SurveyKeyworthNottingham NG12 5GGUK

The evolution of Earth＇s biosphere,atmosphere and hydrosphere is tied to the formation of continental crust and its subsequent movements on tectonic *** supercontinent cycle posits that the continental crust is periodically amalgamated into a single landmass,subsequently breaking up and dispersing into various continental *** is possibly the first true supercontinent,it amalgamated during the 2.0-1.7 Ga period,and collisional orogenesis resulting from its formation peaked at 1.95-1.85 *** and palaeomagnetic evidence indicate that Columbia remained as a quasi-integral continental lid until at least 1.3 *** break-up attempts are evidenced by dyke swarms with a large temporal and spatial range; however,palaeomagnetic and geologic evidence suggest these attempts remained *** than dispersing into continental fragments,the Columbia supercontinent underwent only minor modifications to form the next supercontinent （Rodinia） at 1.1 -0.9 Ga; these included the transformation of external accretionary belts into the internal Grenville and equivalent collisional *** Columbia provides evidence for a form of ‘lid tectonics’,modern style plate tectonics occurred on its periphery in the form of accretionary *** detrital zircon and preserved geological record are compatible with an increase in the volume of continental crust during Columbia＇s lifespan; this is a consequence of the continuous accretionary processes along its *** quiescence in plate tectonic movements during Columbia＇s lifespan is correlative with a long period of stability in Earth＇s atmospheric and oceanic *** variability starting at 1.3 Ga in the environmental record coincides with the transformation of Columbia to Rodinia; thus,the link between plate tectonics and environmental change is strengthened with this interpretation of supercontinent history.

关键词： Rodinia Columbia Supercontinents Continental growth Lid tectonics mesoproterozoic

Selection of Wind Turbine Systems for the Sultanate of Oman

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Computer Systems Science & Engineering 2023年第4期45卷 343-359页

作者： m.A.A.Younis Anas Quteishat Department of Electrical and Computer Engineering Sohar UniversitySultanate of Oman Electrical Engineering Department Faculty of Engineering TechnologyAl-Balqa Applied UniversityAl-SaltJordan

The Sultanate of Oman has been dealing with a severe renewable energy issue for the past few decades,and the government has struggled to find a *** addition,Oman’s strategy for converting power generation to sources of renewable energy includes a goal of 60 percent of national energy demands being met by renewables by 2040,including solar and wind ***,the use of small-scale energy from wind devices has been on the rise in recent *** upward trend is attributed to advancements in wind turbine technology,which have lowered the cost of energy from *** calculate the internal and external factors that affect the small-scale energy of wind technologies,the study used a fuzzy analytical hierarchy process technique for order of preference by similarity to an ideal *** a result,in the decision model,four criteria,seventeen sub-criteria,and three resources of renewable energy were calculated as options from the viewpoint of the Sultanate of *** research is based on an examination of statistics on energy produced by wind turbines at various locations in the Sultanate of ***,six distinct miniature wind turbines were investigated for four different *** outcomes of this study indicate that the tiny wind turbine has a lot of potential in the Sultanate of Oman for applications such as homes,schools,college campuses,irrigation,greenhouses,communities,and small *** government should also use renewable energy resources to help with the renewable energy issue and make sure that the country has enough renewable energy for its long-term growth.

关键词： multi criteria decision making model fuzzy theory fuzzy sets renewable energy wind turbine supplier selection

Viscosity Effects on Anisotropic Universe in Curvature-matter Coupling Gravity

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Communications in Theoretical Physics 2018年第5期69卷 537-543页

作者： m.Sharif Aisha Siddiqa Department of mathematics University of the PunjabQuaid-e-Azam Campus

in this paper, we study evolution of the universe in the background of f(R, T) gravity using LRS Bianchi type-Ⅰ model. We discuss scale factors as well as deceleration parameter in dark energy dominated era for different bulk viscosity models. The occurrence of big-rip singularity is also examined. it is concluded that expansion is faster when bulk viscosity is proportional to Hubble parameter as compared to other models.

关键词： f(R T) gravity anisotropic universe bulk viscosity