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Neuroprotection by resveratrol-glucuronide and quercetin-glucuronide via binding to polyphenol-and glycosaminoglycan-binding sites in the laminin receptor

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Neural regeneration research 2025年第3期20卷 819-820页

作者： rayudu Gopalakrishna j.nnifer Aguilar Emily Lee William j.Mack Department of Integrative Anatomical Sciences Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA Department of Neurological Surgery Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA

The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated ... 详细信息

关键词： resveratrol molar dated

Formation of High-quality Advanced High-k Oxide Layers at Low Temperature by Excimer UV Lamp-assisted Photo-CVD and Sol-gel Processing

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Chemical research in Chinese Universities 2004年第4期20卷 396-402页

作者： YU j. j. Electronic & Electrical Engineering University College London

We have successfully demonstrated that high quality and high dielectric constant layers can be fabricated by low temperature photo-induced or -assisted processing. Ta_2O_5 and ZrO_2 have been deposited at trocessing with the aid of excimer lamps. The UV annealing of as-grown layers was found to significantly improve their electrical properties. Low leakage current densities on the order of 10 -8 A/cm 2 at 1 MV/cm for deposited ultrathin Ta_2O_5 films and ca.10 -6 A/cm 2 for the photo-CVD ZrO_2 layers and photo-irradiated sol-gel HfO_2 layers have been readily achieved. The improvement in the leakage properties of these layers is attributed to the UV-generated active oxygen species O( 1D) which strongly oxidize any suboxides to form more stoichiometric oxides on removing certain defects, oxygen vacancies and impurities present in the as-prepared layers. The photo-CVD Ta_2O_5 films deposited across 10.16-cm Si wafers exhibit a high thickness uniformity with a variation of less than \{±2.0%\} being obtained for ultrathin ca.10 nm thick films. The lamp technology can in principle be extended to larger area wafers, providing a promising low temperature route to the fabrication of a range of high quality thin films for future ULSI technology.

关键词： Excimer lamp High-kdielectrics Thin film Chemical vapour deposition(CVD) Sol-gel processing

Visual ＂playback＂ of colorful signals in the field supports sensory drive for signal detectability

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Current Zoology 2018年第4期64卷 493-498页

作者： Alex r. GUNDErSON Leo j. FLEISHMAN Manuel LEAL Department of Integrative Biology University of California Berkeley CA 94720 USA Department of Biology Union College Schenectady NY 12308 USA Division of Biological Sciences University of Missouri 105 Tucker Hall Columbia MO 65211 USA

Colorful visual signals are important systems for investigating the effects of signaling environ ments and receiver physiology on signal evolution as predicted by the sensory drive hypothesis. Support for the sensory drive hypothesis on color signal evolution is mostly based on document ing correlations between the properties of signals and habitat conditions under which the signals are given （i.e., a correlational approach） and less commonly on the use of mathematical models that integrate representations of visual environments, signal properties, and sensory systems （i.e., a functional approach）. Here, we used an experimental approach in the field to evaluate signal efficacy of colorful lizard throat fans called dewlaps that show geographic variation in the lizard Anolis cristatellus. We used a remote controlled apparatus to display ＂fake dewlaps＂ to wild lizards to test for adaptive divergence in dewlap brightness （i.e., perceived intensity） among populations in situ. We found evidence of local adaptation in dewlap brightness consistent with the sensory drive hypothesis. Specifically, dewlaps that had the brightness characteristics of local lizards were more likely to be detected than those with the brightness characteristics of nonlocal lizards. Our findings indicate that simplified mathematical representations of visual environments may allow robust estimates of relative detectability or conspicuousness in natural habitats. We have shown the feasibility of evaluating color signal efficacy experimentally under natural conditions and dem onstrate the potential advantages of presenting isolated components of signals to an intended re ceiver to measure their contribution to signal function.

关键词： Anolis color signal sensory drive signal evolution

Dewlap size in male water anoles associates with consistent inter-individual variation in boldness

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Current Zoology 2019年第2期65卷 189-195页

作者： Breanna j. PUTMAN Kylee r. AZUrE Lindsey SWIErK Department of Ecology and Evolutionary Biology University of California Los Angeles CA 90095-1606 USA Section of Herpetology and Urban Nature Research Center Natural History Museum of Los Angeles County Los Angeles CA 90007 USA Environmental Science Department Aaniiih Nakoda College Harlem MT 59526 USA dSchool of Forestry and Environmental Studies Yale University New Haven CT 06511 USA

Male sexually selected signals can indicate competitive ability by honestly signaling fitnessrelevant traits such as condition or performance. However, behavior can also influence contest outcomes;in particular, boldness often predicts dominance rank and mating success. Here, we sought to determi ne whether male ornament size is associated with consiste nt in dividual differences in boldness in water anoles Anol is aquaticus. We measured the relative size of the dewlap, a flap of skin under the chin that is a sexually selected ornament in Anolis lizards, and tested for associations with responses to a novel and potentially risky environment: time to emerge from a refuge into an arena and number of head sea ns post-emergence. We found that in dividuals con siste ntly differed in both time to emerge and head sea nning (i.e., in dividual resp on ses were repeatable), and that dewlap size was negatively related to nu mber of head sea ns. This suggests that orname nt size could indicate male boldness if seanning represents antipredator vigilance. We found that males that had larger relative dewlaps were also in better body condition, but boldness (i.e., head scann ing) was not related to condition. Lastly, we found con siste nt d iff ere nces in behavior betwee n trials, showing that anoles were becoming habituated or sensitized to the testing arena. Overall, our study shows that in additi on to indicating con dition and perform a nee, dewlap size could also honestly indicate male boldness in Anolis lizards.

关键词： Anolis aquaticus behavioral syndrome mating success personality signal sexual selection temperament

Modelling ballistic impact on military helmets:The relevance of proj.ctile plasticity

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Defence Technology（防务技术） 2021年第5期17卷 1699-1711页

作者： A.caçoilo r.Mourao F.Teixeira-Dias A.Azevedo F.Coghe r.A.F.Valente School of Engineering The University of EdinburghEdinburghEH93FGUK Dept.Weapon Systems and Ballistics Royal Military AcademyBrusselsBelgium Centre for Mechanical Technology and Automation Department of Mechanical EngineeringUniversity of AveiroPortugal

The need to develop armour systems to protect against attacks from various sources is increasingly a matter of personal,social and national *** develop innovative armour systems it is necessary to monitor developments being made on the type,technology and performance of the threats(weapons,proj.ctiles,explosives,etc.) Specifically,the use of high protection level helmets on the battlefield is *** development of evaluation methods that can predict inj.ries and trauma is therefore of maj.r ***,the risk of inj.ries or trauma that can arise from induced accelerations is an additional *** develop new materials and layouts for helmets it is necessary to study the effects caused by ballistic impacts in the human head on various *** use of numerical simulation is a fundamental tool in this *** work here presented focuses on the use of numerical simulation(finite elements analysis) to predict the consequences of bullet impacts on military helmets on human *** main obj.ctives are to assess the level and probability of head trauma using the Head Inj.ry Criterion,caused by the impact of a 9 mm NATO proj.ctile on a PASGT helmet and to quantify the relevance of proj.ctile plasticity on the whole modelling *** accelerations derived from the impact phenomenon and the deformations caused on the helmet are evaluated using fully three-dimensional models of the helmet,head,neck and *** studies are done at impact angles ranging from 0 to 75°.results are presented and discussed in terms of HIC and probability of acceleration induced trauma *** comparison analyses are done using a rigid and a deformable proj.ctile and it is observed that plastic deformation of the proj.ctile is a significant energy dissipation mechanism in the whole impact process.

关键词： Ballistic impact Helmet impact Plasticity Finite element analysis Inj.ry Trauma HIC

Seamount chains and hotspot tracks:Superficially similar,deeply different

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Geoscience Frontiers 2023年第6期14卷 307-326页

作者： Edgardo cañón-Tapia División de Ciencias de la Tierra CICESE.Carretera Ensenada-Tijuana#3985Ensenada Baja CaliforniaCP 22860Mexico

Nearly 80%of the seafloor extension has not been covered by high-resolution bathymetry,impeding direct observation of ***,lists of seamount location and height at a global scale have been produced using different *** this work four of such databases(publicly available)are compared with each other to assess their *** identify large differences among databases that could have exerted strong influences on models of seamount production and associated geodynamic *** those differences,it is shown that all databases allow the identification of seamount lines both along the present-day Mid Ocean ridge(MOr)system and on intraplate ***,those seamount lines do not coincide with the so-called hotspot tracks that commonly were defined by selectively focusing attention on the larger *** of all the databases also shows that distinction based only on seamount size between seamounts produced at Mid-Ocean ridge(MOr)environments from those associated with mantle-plum fed-hotspot activity has been ***,combined with the fact that most seamount lines defined by the available databases can be traced back to past locations of MOr indicates that most of the present-day intraplate linear arrays of seamounts,which include some large seamounts,were not produced by the action of underlying mantle anomalies envisaged in the form of mantle *** evidence presented here calls for a reassessment of the form in which volcanic and tectonic activities are conceptually related to each other.

关键词： Seamount origin Chains of seamounts Spatial distribution of volcanism Intraplate volcanism Mid Ocean ridge volcanism

Soil Fertility Survey in Western Usambara Mountains, Northern Tanzania

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Pedosphere 2006年第2期16卷 237-244页

作者： P. A. NDAKIDEMI j. M. r. SEMOKA Selian Agricultural research Institute P.O. Box 6024 Arusha (Tanzania) Faculty of Applied ScienceCape Peninsula University of TechnologyCape Town CampusKeizersgrachtP. O. Box 652Cape Town 8000 (South Africa) Sokoine University of Agriculture Soil Science Department P. O. Box 3008Morogoro (Tanzania)

Soil samples from thirty sites representing four agro-ecological zones in the Western Usambara Mountains (WUM) of the Lushoto District in northern Tanzania were collected and analyzed for different nutrients. The results suggested that the maj.r soil fertility constraint was P deficiency. On the basis of critical levels established in other areas, 90% of the soils were ranked as P deficient. This was followed by N, which was ranked as inadequate in 73% of the sites. Magnesium, K, and ca also appeared limiting with 67%, 53% and 50% of the soils falling below the established critical values, respectively. A few soils (10%) were also found to contain exchangeable Al. The metallic micronutrients (Cu, Fe, and Zn) were adequate in all soils. Two sites had excessive Mn that could lead to toxicity in crops, and one was Mn deficient.

关键词： agro-ecological zone P deficiency soil fertility Western Usambara Mountains

MODELING OF 'BANDING' MICrOSTrUCTUrE FOrMATION IN CENTrIFUGALLY SOLIDIFIED Ti-6Al-4V ALLOY

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 399-408页

作者： D.r. Liu E：j. Guo L.P. Wang School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China Institute of Metal research Chinese Academy of Sciences Shenyang 110016 China

Numerical investigations of the ＇banding＇ microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference method （FDM） at the macroscale with a cellular automaton （ca） model at the microscale. The macro model is used to simulate the fluid flow and heat transfer throughout the casting. The micro model is used to predict the nucleation and growth of microstructures. With the proposed model, numerical simulations are performed to study the influences of the nucleation density, mould rotation speed, and casting size upon the ＇banding＇ microstructure formation. It is noted that changing the nucleation density has a minor effect on the microstructure formation. The rotation speed promotes the formation of ＇banding＇ microstructure, which is more noticeable for larger size castings. The ＇maj.r mechanism responsible for this ＇banding＇ phenomenon is the spatial variation in cooling rates created by centrifugal force.

关键词： Modeling 'Banding' microstructure Ti-6Al-4V alloy Centrifugal casting

A Survey and Statistics of Interstellar OH and H_2O Masers

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Chinese j.urnal of Astronomy and Astrophysics 2005年第2期5卷 175-183页

作者： Han-PingLiu j.r.Forster j.nSun DepartmentofPhysics BeijingNormalUniversityBeijing100875 Universityofcalifornia BerkeleyandHatCreekRadioObservatory42231BidwellRoadHatCreekCA96040 DepartmentofAstronomy BeijingNormalUniversityBeijing100875

We present a statistical analysis of a sky survey of interstellar H2O and OH masers. These masers can be classified into three categories: isolated H2O masers, isolated OH masers, and simple OH/H2O maser associations. The total number of sources in each category is of the same order of magnitude, and as an evolutionary phase they can maintain ~ 105 yr. An improved radiative pumping mechanism is proposed. This model avoids some of the deficiencies of previous radiative models, such as shortage of exciting photons. The statistical results obtained from the survey can be interpreted by the new mechanism together with the evolutionary model in which the gravitational force of the central stellar obj.cts is responsible for the HII region.

关键词： surveys masers radiation mechanism: non-thermal HII regions