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the effects of gonadal hormones on learning and memory in male mammals： A review

Current Zoology 2011年第4期57卷 543-558页

作者： stuart t. LEONARD Peter j. WINSAUER Department of Pharmacology and Experimental therapeutics Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

the primary role of the gonadal steroid hormones in mammals is to regulate reproduction and related behaviors; however, both androgens and estrogens are also integrally involved in mediating higher brain function and processes including cognition, neural development, and neural plasticity. In particular, a number of studies show that estradiol modulates dendritic spine growth and synapse density （synaptic plasticity） in the hippocampus of females, and that increased estradiol levels are generally associated with improvements on a variety of learning and memory tasks. While the maj.rity of research has focused on the beneficial effects of estradiol in females, much less attention has been given to testosterone and its effects on learning and memory in males. Similar to estradiol titers in females, testosterone titers in males decline with age, albeit more gradually, and this decline has been correlated with impairment of certain cognitive tasks. Moreover, studies involving both humans and animals indicate that testosterone and its metabolites can augment responding on certain behavioral tasks, depending on the subj.ct＇s current hormonal state, the response required, and the stimuli involved （e.g., those involving spatial or nonspatial stimuli）. While the exact mechanisms by which testosterone exerts its effects on learning and memory are not fully understood, recent findings suggest that testosterone modulates learning and memory in males through an interaction with the cholinergic system. the overall obj.ctive of this review is to discuss studies investigating the role of the gonadal hormones in mediating learning and memory processes in male mammals [Current Zoology 57 （4）： 543-558, 2011].

关键词： testosterone Learning and memory Cholinergic system Mammals Cognition Androgens

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A kinetic model for a single step biodiesel production from a high free fatty acid (FFA) biodiesel feedstock over a solid heteropolyacid catalyst

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Green Energy & Environment 2019年第3期4卷 328-341页

作者： Aashish Gaurav stéphane Dumas Chau t.Q.Mai Flora t.t.Ng Department of Chemical Engineering University of Waterloo

Production of biodiesel from yellow grease(waste cooking oil and waste animal fats) is fast emerging as a promising alternative to address the twin challenges before the biodiesel industry today-fluctuation in prices of vegetable oil and the food versus fuel debate. Yellow grease has a high percentage of free fatty acids(FFA) and proves to be an unsuitable feedstock for biodiesel production from commercially viable alkalicatalyzed production systems due to saponification problems.'Green' methodologies based on heterogeneous solid acid catalyzed reactions have the potential to simultaneously promote esterification and transesterification reactions of yellow grease to produce biodiesel without soap formation and offer easy catalyst separation without generation of toxic streams. this paper presents kinetic studies for the conversion of model yellow grease feeds to biodiesel using a heteropolyacid supported on alumina(HSiW/Al2O3) using a batch autoclave. three model yellow grease feeds were prepared using canola oil with added FFA such as palmitic, oleic and linoleic acid. A pseudo homogeneous kinetic model for the parallel esterification and transesterification was developed. the rate constants and activation parameters for esterification and transesterification reactions for the model yellow grease feeds were determined. the rate constants for esterification are higher than the transesterification rate constants. the kinetic model was validated using the experimental biodiesel data obtained from processing a commercial yellow grease feed. the kinetic model could be used to design novel processes to convert various low-value waste oils, fats and non-food grade oils to sustainable biodiesel.

关键词： Yellow grease Canola oil Free fatty acids Heteropolyacid Kinetics for esterification and transesterification

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trace element characteristics of partial melts produced by melting of metabasalts at high pressures: Constraints on the formation condition of adakitic melts

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Science China Earth Sciences 2006年第9期49卷 915-925页

作者： j. Adam t.H. Green GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with 5 wt.% added H2O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quenched glasses) + residual mineral assemblages of amphibolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine maj.r and trace element compositions of these quenched melts, respectively. Maj.r ele- ment compositions of all the melts are tonalitic- trondhj.mitic, similar to adakite. their trace element characteristics are controlled by coexisting residual minerals. Signatures of adakite such as high Sr/Y, low HREE and negative Nb-ta anomaly, etc. are present only in the melts coexisting with residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amphibole-eclogite). Garnet leads to HREE depletion in melts, whereas rutile controls Nb and ta partitioning during the partial melting and causes negative Nb-ta anomaly in melts. therefore, in addition to garnet, rutile is also a necessary residual phase during the generation of adakite or ttG magmas to account for the negative Nb-ta anomaly of the magmas. the depth for the generation of adakite/ttG magmas via melting of metabasalt must be more than about 50 km based on the approximate 1.5 GPa mini- mum-pressure for rutile stability in the partial melting field of hydrous basalt.

关键词： trace element adakite/ttG magmas partial melting of metabasalt negativeNb-ta anomaly rutile

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Unsteady Internal Flow Conditions of Mini-Centrifugal Pump with Splitter Blades

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j.urnal of thermal Science 2013年第1期22卷 86-91页

作者： t. Shigemitsu j. Fukutomi K. Kaj. t. Wada Institute of technology and Science The University of Tokushima Graduate School of Advanced technology and Science The University of Tokushima

Mini centrifugal pumps having a diameter smaller than lOOmm are employed in many fields. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. therefore, mini cen- trifugal pumps with simple structure were investigated by this research. Splitter blades were adopted in this re- search to improve the performance and the internal flow condition of mini centrifugal pump which had large blade outlet angle. the original impeller without the splitter blades and the impeller with the splitter blades were prepared for experiment. the performance tests are conducted with these rotors in order to investigate the effect of the splitter blades on performance and internal flow condition of mini centrifugal pump. On the other hand, a three dimensional unsteady numerical flow analysis was conducted to investigate the change of the internal flow according to the rotor rotation. It is clarified from the experimental results that the performance of the mini cen- trifugal pump is improved by the splitter blades. the blade-to-blade low velocity region was suppressed in the case with the splitter blades. In addition to that, the unsteady flows near the volute casing tongue were suppressed due to the splitter blades. In the present paper, the performance of the mini centrifugal pump is shown and the un- steady flow condition is clarified with the results of the numerical flow analysis. Furthermore, the effects of the splitter blades on the performance and the unsteady internal flow condition are investigated.

关键词： Mini-centrifugal pump Unsteady flow condition Performance Splitter blades

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Performance Analysis of Mini Centrifugal Pump with Splitter Blades

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j.urnal of thermal Science 2013年第6期22卷 573-579页

作者： t. Shigemitsu j. Fukutomi t. Wada H. Shinohara Institute of technology and Science The University of Tokushima 2-1 Minamijosanjima-cho Tokushima 770-8506Japan Graduate School of Advanced technology and Science The University of Tokushima 2-1 Minamijosanjima-choTokushima 770-8506 Japan

Design method for a mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. then, a semi-open impeller for the mini centrifugal pump with 55mm impeller diameter is adopted in this research to take simplicity and maintenance into consideration. Splitter blades are adopted in this research to improve the performance and internal flow condition of mini centrifugal pump having large blade outlet angle. the performance tests are conducted with these rotors in order to investigate the effect of the splitter blades on the performance and internal flow condition of the mini centrifugal pump. A three dimensional steady numerical flow analysis is conducted to analyze rotor, volute efficiency and loss caused by a vortex. It is clarified from the experimental results that the performance of the mini centrifugal pump is improved by the effect of the splitter blades. Flow condition at outlet of the rotor becomes uniform and back flow regions are suppressed in the case with the splitter ***, the volute efficiency increases and the vortex loss decreases. In the present paper, the performance of the mini centrifugal pump is shown and the flow condition is clarified with the results of the experiment and the numerical flow analysis. Furthermore, the performance analyses of the mini centrifugal pumps with and without the splitter blades are conducted.

关键词： Centrifugal pump Performance Internal flow Splitter blade

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Generation of brain vascular heterogeneity:recent advances from the perspective of angiogenesis

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Neural Regeneration Research 2025年第7期20卷 2013-2014页

作者： Nathanael j.Lee Ryota L.Matsuoka Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Molecular Medicine Cleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOHUSA

Heterogeneous proper t i es of vascular endothelial cells in the brain:the brain displays large energy dynamics and consumption,and this high level of metabolic demands is fulfilled by a continuous supply of glucose and oxygen through its vascular *** vasculature consists of highly divergent blood vessel branches,giving rise to a dense network of capillaries that supply blood to all cells across the *** elaborated vascular network is thought to develop via angiogenesis,a process in which new blood vessels grow from pre-existing *** capillaries exhibit organotypic features distinct from other tissues and are formed primarily by two maj.r endothelial cell(EC)types:those that form the semi-permeable blood-brain barrier(BBB)and those that develop highly permeable pores known as fenestrae(Matsuoka et al.,2022).the structural and functional differences between BBB and fenestrated vascular ECs represent a fundamental feature of brain vasculature and form the foundation for both brain function and homeostasis.

关键词： angiogenesis homeostasis network

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Release, Recycle, Rebuild： Cell-Wall Remodeling, Autodegradation, and Sugar Salvage for New Wall Biosynthesis during Plant Development

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Molecular Plant 2018年第1期11卷 31-46页

作者： William j. Barnes Charles t. Anderson Department of Biology Center for Ugnocellulose structure and Formation the Pennsylvania state University University Park PA 16802 USA

Plant cell walls contain elaborate polysaccharide networks and regulate plant growth, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell wall is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during growth and development. Far from being a terminal carbon sink, many wall polymers can be degraded and recycled by plant cells, either via direct re-incorporation by trans- glycosylation or via internalization and metabolic salvage of wall-derived sugars to produce new precur- sors for wall synthesis. However, the physiological and metabolic contributions of wall recycling to plant growth and development are largely undefined. In this review, we discuss long-standing and recent evi- dence supporting the occurrence of cell-wall recycling in plants, make predictions regarding the develop- mental processes to which wall recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of wall dynamics and metabolism.

关键词： Plant cell walls wall degradation wall recycling wall biosynthesis

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Autodesk inventor 11 essentials plus Daniel t. Banach, travis j. j.nes, Alan j. Kalamej.

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2006年

作者： Daniel t. Banach travis j. j.nes Alan j. Kalamej.

来源：畅想之星图书光盘版（南... 评论

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study of neutron response for two hybrid RPC setups using the GEANt4 MC simulation approach

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Chinese Physics C 2009年第10期33卷 887-891页

作者： M. j.mil j. t. Rhee Y. j. j.on Institute for Advanced Physics Konkuk University Liquid Crystal Research Center Konkuk University

the present article describes a detailed neutron simulation study in the energy range 10^-10 MeV to 1.0 GeV for two different RPC configurations. the simulation studies were taken by using the GEANt4 MC code. Aluminum was utilized on the GND and readout strips for the （a） Bakelite-based and （b） glass-based RPCs. For the former type of RPC setup the neutron sensitivity for the isotropic source was Sn = 2.702 × 10^-2 at En = 1.0 GeV, while for the latter type of RPC, the neutron sensitivity for the same source was evaluated as Sn = 4.049 × 10^-2 at En = 1.0 GeV. these results were further compared with the previous RPC configuration in which copper was used for ground and pickup pads. Additionally A1 was employed at （GND＋strips） of the phosphate glass RPC setup and compared with the copper-based phosphate glass RPC. Good agreement with sensitivity values was obtained with the current and previous simulation results.

关键词： resistive plate chambers neutron sensitivity GEANt4 Monte Carlo simulation

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Grain Size Distribution and Interfacial Heat transfer Coefficient during Solidification of Magnesium Alloys Using High Pressure Die Casting Process

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j.urnal of Materials Science & technology 2018年第2期34卷 324-334页

作者： P. Sharifi j. j.mali K. Sadayappan j.t. Wood Western University London Ontario Canada Canmet MAtERIALS Hamilton ON Canada

the obj.ctive of this study is to predict grain size and heat transfer coefficient at the metal-die interface during high pressure die casting process and solidification of the magnesium alloy AM60. Multiple runs of the commercial casting simulation package, ProCAsttM, were used to model the mold filling and solidification events employing a range of interfacial heat transfer coefficient values. the simulation results were used to estimate the centerline cooling curve at various locations through the casting. the centerline cooling curves, together with the die temperature and the thermodynamic properties of the alloy, were then used as inputs to compute the solution to the stefan problem of a moving phase boundary, thereby providing the through-thickness cooling curves at each chosen location of the casting, Finally, the local cooling rate was used to calculate the resulting grain size via previously established relationships. the effects of die temperature, filling time and heat transfer coefficient on the grain structure in skin region and core region were quantitatively characterized. It was observed that the grain size of skin region strongly depends on above three factors whereas the grain size of core region shows dependence on the interracial heat transfer coefficient and thickness of the samples. the grain size distribution from surface to center was estimated from the relationship between grain size and the predicted cooling rate. the prediction of grain size matches well with experimental results. A comparison of the predicted and experimentally determined grain size profiles enables the determination of the apparent interracial heat transfer coefficient for different locations.

关键词： High pressure die casting Grain size lnterfacial heat transfer coefficient Solidification of magnesium alloys Process parameters

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