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Shark scavenging behavior in the presence of competition

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Current Zoology 2010年第1期56卷 100-108页

作者： Shannon P.GERRY Andrea j.scott Department of Biological Sciences University of Rhode Island Department of Biological Sciences Wellesley College

The distribution of organisms within a community can often be determined by the degree of plasticity or degree of specialization of resource acquisition. Resource acquisition is often based on the morphology of an organism, behavior, or a combination of both. Performance tests of feeding can identify the possible interactions that allow one species to better exploit a prey item. Scavenging behaviors in the presence or absence of a competitor were investigated by quantifying prey selection in a trophic generalist, spiny dogfish Squalus acanthias, and atrophic specialist, smooth-hounds Mustelus canis, in order to determine if each shark scavenged according to its jaw morphology. The diet of dogfish consists of small fishes, squid, ctenophores, and bi- valves; they are expected to be nonselective predators. Smooth-hounds primarily feed on crustaceans; therefore, they are predicted to select crabs over other prey types. Prey selection was quantified by ranking each prey item according to the order it was consumed. Dietary shifts were analyzed by comparing the percentage of each prey item selected during solitary versus competitive scavenging. When scavenging alone, dogfish prefer herring and squid, which are easily handled by the cutting dentition of dogfish. Dogfish shift their diet to include a greater number of prey types when scavenging with a competitor. Smooth-hounds scavenge on squid, herring, and shrimp when alone, but increase the number of crabs in the diet when scavenging competitively. Competition causes smooth-hounds to scavenge according to their jaw morphology and locomotor abilities, which enables them to feed on a specialized resource [Current Zoology 56 （1）： 100-108 2010].

关键词： Optimal foraging theory Prey selection Squalus acanthias Mustelus canis

Heterozygous carriers of galactocerebrosidase mutations that cause Krabbe disease have impaired microglial function and defective repair of myelin damage

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Neural Regeneration Research 2018年第3期13卷 393-401页

作者： Nicole j.scott-Hewitt Christopher j.Folts Mark D.Noble Department of Biomedical Genetics University of Rochester School of Medicine and Dentistry

This review addresses two puzzling findings related to mutations in galactocerebrosidase （GALC） that cause Krabbe disease （KD）, a severe lysosomal storage disorder characterized by extensive myelin damage in children with mutations in both GALC alleles. First, heterozygous carriers of KD-causing mutations, which include the biological parents of children with KD, exhibit increased risk for developing other diseases. Second, variants in the GALC locus increase the risk of developing multiple sclerosis （MS）, another disease characterized by extensive myelin damage. What explains these correlations？ In studies on cuprizone-induced myelin damage in heterozygous （GALC＋/–） mice carrying one copy of a mutation that causes KD-like disease, the extent of damage was similar in GALC＋/– and wild-type （WT） mice. In contrast, GALC＋/- mice had striking defects in repair of cuprizone-induced damage. We further found unexpected microglial defects in myelin debris clearance and in the ability to up-regulate the Trem2 microglial protein critical for debris uptake. These defects were rescued by exposure to a lysosomal re-acidifying drug discovered in our studies on KD, and which provides multiple clinically relevant benefits in the twitcher （GALC＋/–） mouse model of KD. Thus, heterozygous GALC mutations cause effects on biological function that may help to understand the increased disease risk in heterozygous carriers of such mutations and to understand why GALC variations increase the risk of MS. Our findings indicate that while some genetic risk factors may contribute to complex diseases by increasing the risk of tissue damage, others may do so by compromising tissue repair.

关键词： vulnerability locus multiple sclerosis Krabbe disease galactocerebrosidase microglia myelin repair lysosomal storage disorders heterozygous carriers Trem2 demyelination

ITERATIVE METHODS OF OBTAINING ESTIMATES FOR INCOMPLETE CONTINGENCY TABLES

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Systems Science and Mathematical Sciences 1989年第2期2卷 119-128页

作者：王东谦 David j.scott La Trobe University Bundoora VictoriaAustralia

An iterative method of De jong,Greig and Madan(1985)for obtaining maximum likelihoodestimates for contingency tables derived from a Mover-Stayer model is *** is shown that thismethod works for other sampling schemes l... 详细信息

关键词： Incomplete contingency tables maximum likelihood estimates Mover-Stayer model iterative method

Advances in minimally invasive treatment of hemorrhagic and ischemic stroke

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Neural Regeneration Research 2016年第2期11卷 228-229页

作者： Robert C.Rennert j.scott Pannell Alexander A.Khalessi Department of Neurosurgery University of California - San Diego

Cerebrovascular diseases,including ischemic and hemorrhagic strokes,affect more than 6 million US adults *** cause high rates of morbidity and mortality due to the central nervous system’s sensitivity to disruptions in blood flow,and are refractory to traditional surgical interventions.A variety of minimally invasive surgical and endovascular approaches have recently been developed to improve patient outcomes following stroke.

关键词： Advances in minimally invasive treatment of hemorrhagic and ischemic stroke ICH

Surface texture evaluation of additively manufactured metallic cellular scaffolds for acetabular implants using *** computed tomography

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Bio-Design and Manufacturing 2019年第2期2卷 55-64页

作者： Shan Lou Luca Pagani Wenhan Zeng Muhammad U.Ghori Xiangqian jiang Paul j.scott EPSRC Future Metrology Hub University of HuddersfieldQueensgateHuddersfield HD1 3DHUK Department of Pharmacy University of HuddersfieldQueensgateHuddersfield HD1 3DHUK

The surface topography of acetabular implants plays a key role in providing cell attachment and *** measurement and characterisation of the surface texture of the cellular scaffold layer on the acetabular cup are very difficult due to the 3D nature of scaffold *** is proposed to use X-ray computed tomography(XCT)to measure the surface texture of an electron beam melting-produced titanium acetabular *** surface texture of its cellular scaffold is evaluated using the newly developed 3D surface texture parameters,which allows surface characterisation on 3D triangular mesh *** commonly used height parameters,*** arithmetical mean height Sa,the root mean square height Sq,the skewness Ssk and the kurtosis Sku,are calculated from surface patches extracted from the XCT scanned triangular mesh *** addition,the surface peak density and pit density,which are more related to cell communication and proliferation,are estimated based on the 3D watershed *** Wolf pruning with an empirical threshold 12μm is used to control the over-segmentation.

关键词： Additive manufacturing Cellular scaffold Surface texture X-ray computed tomography

Double Fertilization in Arabidopsis thaliana Involves a Polyspermy Block on the Egg but Not the Central Cell

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Molecular Plant 2008年第4期1卷 611-619页

作者： Rod j. scott Susan j. armstrong james Doughty Melissa Spielman Department of Biology and Biochemistry University of Bath Claverton Down Bath BA2 7AY United Kingdom School of Biosciences The University of Birmingham Edgbaston Birmingham B15 2TT United Kingdom

In animal reproduction, thousands of sperm may compete to fertilize a single egg, but polyspermy blocks prevent multiple fertilization that would otherwise lead to death of the embryo. In flowering plants, successful seed development requires that only two sperm are delivered to the embryo sac, where each must fertilize a female gamete （egg or central cell） to produce the embryo and endosperm. Therefore, polyspermy must be avoided, not only to prevent abnormalities in offspring, but to ensure double fertilization. It is not understood how each sperm fertilizes only one female gamete, nor has the existence of polyspermy barriers been directly tested in vivo. Here, we sought evidence for poly- spermy blocks in angiosperms using the polyspermic tetraspore （tes） mutant of Arabidopsis, which allows in-vivo challenge of egg and central cell with multiple male gametes. We show that tes mutant pollen tubes can transmit more than one sperm pair to an embryo sac, and that sperm from more than one pair can participate in fertilization. We detected endosperms but not embryos with ploidies that could only result from multiple fertilization. Our results therefore demonstrate an in-vivo polyspermy block on the egg, but not the central cell of a flowering plant.

关键词： Double Fertilization Arabidopsis thaliana Involves Polyspermy Block Central Cell

Immune Activation in the Liver by Nucleic Acids

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journal of Clinical and Translational Hepatology 2016年第2期4卷 151-157页

作者： Qian Sun Qingde Wang Melanie j.scott Timothy R.Billiar Department of Surgery University of PittsburghPittsburghPAUSA

Viral infection in the liver,including hepatitis B virus (HBV) and hepatitis C virus (HCV) infection,is a major health problem worldwide,especially in developing *** infection triggers a pro-inflammatory response in patients that is crucial for host *** studies have identified multiple transmembrane and cytosolic receptors that recognize pathogen-derived nucleic acids,and these receptors are essential for driving immune activation in the *** addition to sensing DNA/RNA from pathogens,these intracellular receptors can be activated by nucleic acids of host origin in response to sterile *** this review,we discuss the expanding roles of these receptors in both immune and nonimmune cells in the liver.

关键词： Nucleic acid Innate immunity Intracellular receptor Hepatocytes

3rd ANtarctic Gravity Wave Instrument Network(ANGWIN)Science Workshop

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Advances in Atmospheric Sciences 2017年第1期34卷 1-3页

作者： Tracy MOFFAT-GRIFFIN Mike j.TAYLOR Takuji NAKAMURA Andrew j.KAVANAGH j.scott HOSKING Andrew ORR Britsh Antarctic survey High CrossCambridge CB30ETUK Utah State University LoganUT84322USA National Institute of Polar Research Tachikawa-shiTokyo 190-8518Japan

1. Overview The 3rd ANtarctic Gravity Wave Instrument Network （ANGWIN） science workshop was held on 12-14 April 2016 in Cambridge, UK. ANGWIN is a highly successful grassroots program that was started in 2011 （in the Cornish English dialect ANGWIN means ＂the white＂）. Although ini- tially focused on the Antarctic, we now aim to develop collaborations in both polar regions.

关键词： ANGWIN)Science Workshop Wave

A highly efficient photocatalytic system for environmental applications based on TiO_(2) nanomaterials

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Industrial Chemistry & Materials

Industrial Chemistry & Materials 2023年第3期1卷 431-442页

作者： Sapanbir S.Thind Mathias Paul john B.Hayden Anuj joshi David Goodlett j.scott McIndoe Department of Chemistry University of Victoria3800 Finnerty RoadVictoriaBCV8P 5C2 Canada Waterdrape LLC Paradise ValleyArizonaUSA Genome BC Proteomics Centre University of VictoriaVictoriaBritish ColumbiaCanada

Sustainable and efficient water treatment techniques to improve the quality of water for various applications include advanced oxidation processes(AOP),mainly focusing on heterogeneous *** science and nanotechnology have contributed to tailoring the properties of photocatalytic materials to significantly enhance their photoactivity and *** we report the development of a well-organized nanoporous TiO_(2)-based photocatalytic reactor for water *** TiO_(2) materials were directly grown using a two-step electrochemical anodization process in ethylene glycol+0.3 wt%NH_(4)F+2 wt%H_(2)*** prepared nanomaterials were characterized by X-ray diffraction(XRD),scanning electron microscope(SEM),and energy-dispersive X-ray spectroscopy(EDX).To enhance the photocatalytic activity of the system,water scrubbing was incorporated to boost the presence of oxygen in the water,enhancing the electron uptake at the conduction band thus significantly reducing the electron–hole recombination and increasing the photocatalytic *** further enhance the efficiency and reduce the negative environmental impact of the technology,a UVA-LED assembly was used instead of the typical mercury-based UV lamps for *** nanoporous TiO_(2) was tested as a catalyst for the photochemical oxidation of various categories of pollutants;dye(methylene blue),and the removal of microbes such as *** photoreactor developed in this research work was also successfully applied and tested in real-world applications such as keeping heavily used hot-tub water clean without using harmful chemicals(chlorine,bromine,ozone,etc.)or expensive *** simplicity and efficacy of the new approach described in this study make possible the integration of nanoporous TiO_(2) in the design of high-performance air and water purification technologies.

关键词： TiO_(2)photocatalyst UVA-LEDs Nanostructured materials Photochemical oxidation Wastewater treatment Water scrubbing