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

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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

Endovascular thrombectomy for stroke: current best practice and future goals

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Stroke & Vascular Neurology 2016年第1期1卷 16-22页

作者： Bruce C V campbell Geoffrey A Donnan peter j.Mitchell Stephen M Davis Department of Medicine and Neurology Melbourne Brain Centre at the Royal Melbourne HospitalUniversity of MelbourneParkvilleVictoriaAustralia The Florey Institute of Neuroscience and Mental Health University of MelbourneParkvilleVictoriaAustralia Department of Radiology Royal Melbourne HospitalUniversity of MelbourneParkvilleVictoriaAustralia

Endovascular thrombectomy for large vessel ischaemic stroke substantially reduces disability,with recent positive randomised trials leading to guideline changes *** review discusses in detail the evidence provided by recent randomised trials and metaanalyses,the remaining areas of uncertainty and the future directions for *** data from existing trials have demonstrated the robust benefit of endovascular thrombectomy for internal carotid and proximal middle cerebral artery *** remains for more distal occlusions where the efficacy of alteplase is greater,less tissue is at risk and the safety of endovascular procedures is less *** artery occlusion was excluded from the trials,but with a dire natural history and proof of principle that rapid reperfusion is effective,it seems reasonable to continue treating these patients pending ongoing trial *** has been no evidence of heterogeneity in treatment effect in clinically defined subgroups by age,indeed,those aged>80 years have at least as great an overall reduction in disability and reduced *** there was no heterogeneity across the range of baseline stroke severities included in the *** that routine use of general anaesthesia reduces the benefit of endovascular thrombectomy is increasing and conscious sedation is generally preferred unless severe agitation or airway compromise is *** impact of time delays has become clearer with description of onset to imaging and imaging to reperfusion *** in the onset to imaging reduce the proportion of patients with salvageable brain ***,in the presence of favourable imaging,rapid treatment appears beneficial regardless of the onset to imaging time *** to reperfusion delays lead to decay in the clinical benefit achieved,particularly in those with less robust collateral *** brain imaging options to assess prognosis have various advantages and disadvan

关键词： routine epoch benefit

Polyelectrolyte multilayer electrostatic gating of graphene field-effect transistors

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Nano Research 2014年第11期7卷 1650-1658页

作者： Yung Yu Wang peter j. Burke Department of Chemical Engineering and Materials Science University of California Irvine Irvine California 92697 USA Department of Electrical Engineering and Computer Science University of California Irvine Irvine California 92697 USA

We apply polyelectrolyte multilayer films by consecutive alternate adsorption of positively charged polyallylamine hydrochloride and negatively charged sodium polystyrene sulfonate to the surface of graphene field effect transistors. Oscillations in the Dirac voltage shift with alternating positive and negative layers clearly demonstrate the electrostatic gating effect in this simple model system. A simple electrostatic model accounts well for the sign and magnitude of the Dirac voltage shift. Using this system, we are able to create p-type or n-type graphene at will. This model serves as the basis for understanding the mechanism of charged polymer sensing using graphene devices, a potentially technologically important application of graphene in areas such as DNA sequencing, biomarker assays for cancer detection, and other protein sensing applications.

关键词： dirac point graphene transistor electrostatic gating polyallylaminehydrochloride (PAH) sodium polystyrenesulfonate (PSS)

Three-dimensional simulation of liquid inj.ction,film formation and transport,in fluidized beds

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Particuology 2009年第5期7卷 337-346页

作者： Paul Zhao peter j. O'Rourke Dale Snider CPFD Software LLCAlbuquerqueNM 87111USA CFD d'OR Software and Consulting LLCLos AlamosNM 87544USA

Liquid inj.ction, and film formation and transport in dense-phase gas-solids fluidized beds are numerically simulated in three dimensions using a collisional exchange model that is based on the mechanism that collisions cause transfer of liquid mass, momentum, and energy between particles. In the model, each of the particles is represented by a solid core and a liquid film surrounding the core. The model is incorporated in the framework of the commercial code Barracuda developed by CPFD Software. The commercial software is an advanced CFD-based computational tool where the particles are treated as discrete entities, calculated by the MP-PIC method, and tracked using the Lagrangian method. Details of the collisional liquid transfer model have been previously presented in O＇Rourke, Zhao, and Snider （2009）; this paper presents new capabilities and proof-testing of the collision model and a new method to better quantify the penetration length. Example calculations of a fluidized bed without liquid inj.ction show the expected effect of collisions on the reduction of granular temperature （fluctuational kinetic energy） of the bed. When applied to liquid inj.ction into a dense-phase fluidized bed under different conditions, the model predicts liquid penetration lengths comparable to the experiments. In addition, the simulation reveals for the first time the dynamic mixing of the liquid droplets with the bed particles and the transient distribution of the droplets inside the bed.

关键词： MP-PIC Liquid inj.ction Fluidized bed Particle collisions CPFD j.t penetration

iGenetics a Mendelian approach peter j. Russell.

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iGenetics a Mendelian approach Peter J. Russell.

Light metal compound casting

2006年

作者： peter j. Russell.

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

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Science China(Technological Sciences) 2009年第1期52卷 46-51页

作者： Konrad j. M. PAPIS j.erg F. LOEFFLER peter j. UGGOWITZER ETH Zurich Laboratory of Metal Physics and Technology Wolfgang-Pauli-Str. 10

‘Compound casting’simplifies j.ining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as j.int structures of spaceframe constructions in transport industry. In this proj.ct, ‘compound casting’ of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu- ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the j.ining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and Al12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protective coating to the substrate.

关键词： compound casting aluminium alloys magnesium alloys interface structure

Algorithms for enumeration problem of linear congruence modulo m as sum of restricted partition numbers

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Frontiers of Mathematics in China 2015年第1期10卷 69-89页

作者： Tian-Xiao HE peter j. -S. SHIUE Department of Mathematics Illinois Wesleyan University Bloomington IL 61702 USA Department of Mathematical Sciences University of Nevada Las Vegas Las Vegas NV 89154-4020 USA

We consider the congruence x1＋ x2 ＋… ＋ xr - c （mod m）, wherem and r are positive integers and c ∈Zm ：= {0, 1, ..., m- 1} （m ≥ 2）. Recently,W.-S. thou, T. X. He,and peter j.-S. Shiue considered the enumerationproblems of this congruence, namely, the number of solutions with the restriction x1≤~ x2≤ ... ≤ xr, and got some properties and a neat formula ofthe solutions. Due to the lack of a simple computational method for calculating the number of the solution of the congruence, we provide an algebraic and a recursive algorithms for those numbers. The former one can also give a new and simple approach to derive some properties of solution numbers.

关键词： Congruence multiset congruence solution restricted integerpartition

Making the link between ADF and 4D STEM:Resolution,transfer and coherence

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Chinese Physics B 2024年第11期33卷 26-33页

作者： peter D.Nellist Timothy j.Pennycook Department of Materials University of OxfordOxfordUK EMAT University of AntwerpGroenenborgerlaan 1712020 AntwerpBelgium

Steve Pennycook is a pioneer in the application of high-resolution scanning transmission electron microscopy(STEM)and in particular the use of annular dark-field(ADF)*** we show how a general framework for 4D STEM allows clear links to be made between ADF imaging and the emerging methods for reconstructing images from 4D STEM data *** show that both ADF imaging and ptychographical reconstruction can be thought of in terms of integrating over the overlap regions of diffracted discs in the detector *** approach allows the similarities in parts of their transfer functions to be understood,though we note that the transfer functions for ptychographic imaging cannot be used as a measure of information *** also show that conditions of partial spatial and temporal coherence affect ADF imaging and ptychography similarly,showing that achromatic interference can always contribute to the image in both cases,leading to a robustness to partial temporal coherence that has enabled high-resolution imaging.

关键词： image forming and processing phase retrieval electron microscopy scanning transmission electron microscope(STEM)

Association of Psb28 and Psb27 Proteins with PSII-PSI Supercomplexes upon Exposure of Synechocystis sp. PCC 6803 to High Light

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Molecular Plant 2017年第1期10卷 62-72页

作者： Martina Beckova Zdenko Gardian j.anfeng Yu peter Konik peter j. Nixon j.sef Komenda Institute of Microbiology Center Algatech Opatovicky mlyn37981 Trebon Czech Republic Faculty of Science University of South Bohemia Branisovska 1760 37005 Ceske Budejovice Czech Republic Institute of Plant Molecular Biology Biology Centre Academy of Sciences Branisovska 3137005 Ceske Budejovice Czech Republic Sir Ernst Chain Building-Wolfson Laboratories Department of Life Sciences Imperial College London South Kensington Campus London SW7 2AZ UK

Formation of the multi-subunit oxygen-evolving photosystem II （PSII） complex involves a number of auxiliary protein factors. In this study we compared the localization and possible function of two homolo- gous PSU assembly factors, Psb28-1 and Psb28-2, from the cyanobacterium Synechocystis sp. PCC 6803. We demonstrate that FLAG-tagged Psb28-2 is present in both the monomeric PSII core complex and a PSII core complex lacking the inner antenna CP43 （RC47）, whereas Psb28-1 preferentially binds to RC47. When cells are exposed to increased irradiance, both tagged Psb28 proteins additionally associate with oligo- meric forms of PSII and with PSII-PSI supercomplexes composed of trimeric photosystem I （PSI） and two PSII monomers as deduced from electron microscopy. The presence of the Psb27 accessory protein in these complexes suggests the involvement of PSI in PSII biogenesis, possibly by photoprotecting PSII through energy spillover. Under standard culture conditions, the distribution of PSII complexes is similar in the wild type and in each of the single psb28 null mutants except for loss of RC47 in the absence of Psb28-1. In comparison with the wild type, growth of mutants lacking Psb28-1 and Psb27, but not Psb28-2, was retarded under high-light conditions and, especially, intermittent high-light/dark conditions, emphasizing the physiological importance of PSII assembly factors for light acclimation.

关键词： Psb28 proteins photosystem I and II Synechocystis