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Multilayer network analysis:new opportunities and challenges for studying animal social systems

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Current Zoology 2021年第1期67卷 45-48页

作者： matthew J.HASENJAGER matthew SILk David N.FISHER Department of Biological Sciences Royal HollowayUniversity of LondonEghamUK Centre for Ecology and Conservation University of ExeterExeterUK School of Biological Sciences University of AberdeenAberdeenUK

Introduction Many behavioral,ecological,and evolutionary processes are closely intertwined with patterns of social interactions,such as the evolution of cooperation(Croft et al.2006),information and disease transmission(VanderWaal et al.2014;Aplin et al.2015),predator-prey dynamics(Ioannou et al.2012),and dispersal decisions(Blumstein et al.2009).Even in species where individuals are traditionally viewed as leading a relatively solitary existence,interac-tions occur across diverse contexts,including territorial defense,resource competition,and courtship.

关键词： solitary predator network

Comparative insights into mitochondrial adaptations to anoxia in brain

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Neural Regeneration Research 2016年第5期11卷 723-724页

作者： matthew E.Pamenter Department of Biology University of Ottawa

Numerous diseases and pathologies impair the delivery of oxygen to brain, with rapid and deleterious consequences. For example, diseases related to systemic hypoxemia （e.g., chronic pulmonary disorders, cystic fibrosis）, decreased oxygen carrying capacity of blood （e.g., anemia）, or decreased transport （e.g., heart attack, stroke） can all reduce or entirely prevent the delivery of oxygen to brain cells, resulting in the initiation of programmed cell death pathways, necrosis, or excitotoxic cell death in brain （Pamenter, 2014）. However, oxygen-limited environments are common on earth and many organisms naturally experience periods of intermit- tent or prolonged hypoxia or anoxia in their daily and/or annual life cycles （Bickler and Buck, 2007）.

关键词： Comparative insights into mitochondrial adaptations to anoxia in brain

A miniature triaxial apparatus for investigating the micromechanics of granular soils with in situ X-ray micro-tomography scanning

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 357-373页

作者： Zhuang CHENG Jianfeng WANG matthew Richard COOP Guanlin YE Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China Shenzhen Research Institute of City University of Hong Kong Shenzhen 518057China Department of Civil Environmental and Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUK Department of Civil Engineering Shanghai Jiaotong UniversityShanghai 200240China

The development of a miniature triaxial apparatus is *** conjunction with an X-ray microtomography(termed as X-ray fiCT hereafter)facility and advanced image processing techniques,this apparatus can be used for in situ investigation of the micro-scale mechanical behavior of granular soils under *** apparatus allows for triaxial testing of a miniature dry sample with a size of 8 mm x 16 mm(diameter x height).In situ triaxial testing of a 0.4-0.8 mm Leighton Buzzard sand(LBS)under a constant confining pressure of 500 kPa is *** evolutions of local porosities(i.e.,the porosities of regions associated with individual particles),particle kinematics(i.e.,particle translation and particle rotation)of the sample during the shear are quantitatively studied using image processing and analysis ***,a novel method is presented to quantify the volumetric strain distribution of the sample based on the results of local porosities and particle *** is found that the sample,with nearly homogenous initial local porosities,starts to exhibit obvious inhomogeneity of local porosities and localization of particle kinematics and volumetric strain around the peak of deviatoric *** the post-peak shear stage,large local porosities and volumetric dilation mainly occur in a localized *** developed triaxial apparatus,in its combined use of X-ray|iCT imaging techniques,is a powerful tool to investigate the micro-scale mechanical behavior of granular soils.

关键词： triaxial apparatus X-ray fiCT in situ test micro-scale mechanical behavior granular soils

Interactive effects of reproductive assets and ambient predation risk on the threat-sensitive decisions of Trinidadian guppies

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Current Zoology 2016年第3期62卷 221-226页

作者： Jemma KATWAROO-ANDERSEN Chris K. ELVIDGE Indar RAMNARINE grant E. BROWN Department of Biology Concordia University 7141 Sherbrooke St. West Montreal QC H4B 1R6 Canada Department of Life Sciences University of the West Indies St. Augustine Trinidad and Tobago

Threat-sensitive behavioral trade-offs allow prey animals to balance the conflicting demands of successful predator detection and avoidance and a suite of fitness-related activities such as forag- ing, mating, and territorial defense. Here, we test the hypothesis that background predation level and reproductive status interact to determine the form and intensity of threat-sensitive behavioral decisions of wild-caught female Trinidadian guppies Poecilia reticulata. Gravid and nongravid gup- pies collected from high- and low-predation pressure populations were exposed to serial dilutions of conspecific chemical alarm cues. Our results demonstrate that there was ＇no effect of reproduct- ive status on the response of females originating from a low-predation population, with both gravid and nongravid guppies exhibiting strong anti-predator responses to the lowest concentration of alarm cues tested. Increasing cue concentrations did not result in increases in response intensity. Conversely, we found a significant effect of reproductive status among guppies from a high- predation population. Nongravid females from the high-predation population exhibited a strong graded （proportional） response to increasing concentrations of alarm cue. Gravid females from the same high-predation population, however, shifted to a nongraded response. Together, these re- sults demonstrate that accrued reproductive assets influence the threat-sensitive behavioral deci- sions of prey, but only under conditions of high-ambient predation risk.

关键词： asset protection antipredator behavior fitness trade-offs ecological uncertainty chemical alarm cues.

The role of DJ-1 complexes and catecholamine metabolism： relevance for familial and idiopathic Parkinson＇s disease

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Neural Regeneration Research 2018年第5期13卷 815-816页

作者： Dominik Piston matthew E.Gegg German Centre for Neurodegenerative Diseases (DZNE) Bonn Germany Department of Clinical Neuroscience UCL Institute of Neurology London UK

Autosomal recessive mutations in the PARK7 gene,which encodes for the protein DJ-1,result in a loss of function and are a cause of familial Parkinson’s disease（PD）,while increased wild-type DJ-1protein levels are associated with some forms of *** functions of DJ-1 have been described,with the greatest evidence indicating that DJ-1 is a redox-sensitive protein involved in the regulation of oxidative stress and cell survival.

关键词： The role of DJ-1 complexes and catecholamine metabolism relevance for familial and idiopathic Parkinson’s disease GBA DA

Radiofrequency ablation for early oesophageal squamous neoplasia:Outcomes form United Kingdom registry

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World Journal of Gastroenterology 2013年第36期19卷 6011-6019页

作者： Rehan J Haidry Mohammed A Butt Jason Dunn matthew Banks Abhinav Gupta Howard Smart Pradeep Bhandari Lesley Ann Smith Robert Willert grant Fullarton Morris John Massimo Di Pietro Ian Penman Marco Novelli Laurence B Lovat Department of Surgery and Interventional Science National Medical Laser Centre UCL Department Gastroenterology University College Hospital NHS Foundation Trust Department Gastroenterology Guy’s and St Thomas’ Hospitals NHS Trust Institute for Medical Informatics Oslo University Hospital Department Gastroenterology Royal Liverpool University Hospital Merseyside Department Gastroenterology Princess Alexandra Hospital Cosham Department Gastroenterology Bradford Royal Infirmary Bradford Department Gastroenterology Central Manchester University Hospital Department Gastroenterology Glasgow Royal Infirmary Department Gastroenterology Addenbrooke’s Hospital Royal Infirmary Edinburgh

AIM:To report outcomes on patients undergoing radiofrequency ablation(RFA)for early oesophageal squamous neoplasia from a National ***:A Prospective cohort study from 8 tertiary referral centres in the United *** with squamous high grade dysplasia(HGD)and early squamous cell carcinoma(ESCC)confined to the mucosa were *** lesions were removed by endoscopic mucosal resection(EMR)before *** initial RFA treatment,patients were followed up *** flat dysplasia was treated with RFA until complete reversal dysplasia(CR-D)was achieved or progression to invasive Squamous cell cancer defined as infiltration into the submucosa layer or *** main outcome measures were CR-D at 12 mo from start of treatment,long term durability,progression to cancer and adverse ***:Twenty patients with squamous HGD/ESCC completed treatment *** patients(25%)had EMR before starting RFA ***-D was 50%at12 mo with a median of 1 RFA treatment,mean 1.5(range 1-3).Two further patients achieved CR-D with repeat RFA after this *** per cent with CR-D remain dysplasia free at latest biopsy,with median follow up 24 mo(IQR 17-54).Six of 20 patients(30%)progressed to invasive cancer at 1 *** patients(20%)required endoscopic dilatations for symptomatic structuring after *** of these patients have required serial dilatations thereafter for symptomatic dysphagia with a median of 4 dilatations per *** other 2 patients required only a single dilatation to achieve an adequate symptomatic *** patient developed cancer during follow up after end of treatment ***:The role of RFA in these patients re-mains *** our series 50%patients responded at12 *** figures are lower than limited published data.

关键词： Squamous neoplasia Oesophageal cancer Endoscopic mucosal resection High-grade dysplasia Radiofrequency ablation

Local predation risk shapes spatial and foraging neophobia patterns in Trinidadian guppies

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Current Zoology 2016年第5期62卷 457-462页

作者： Chris K. ELVIDGE Pierre J.C. CHUARD grant E. BROWN Department of Biology Concordia University 7141 Sherbrooke St. West Montreal QC H4B 1R6 Canada

The ＂dangerous niche＂ hypothesis posits that neophobia functions to reduce the cost of habitat use among animals exposed to unknown risks. For example, more dangerous foraging or higher competi- tion may lead to increased spatial neophobia. Likewise, elevated ambient predation threats have been shown to induce phenotypically plastic neophobic predator avoidance. In both cases, neophobia is argued to reduce the cost of living associated with ecological uncertainty. Here, we test the hypothesis that ambient predation shapes both neophobic predator avoidance and spatial and foraging neophobia in Trinidadian guppies. Guppies were exposed to a novel foraging arena paired with a known cue （conspecific alarm cue）, a novel cue （lemon odor）, or a stream water control in three streams differing in ambient predation risk. We demonstrate that guppies from a high-predation-risk stream exhibited risk-averse foraging patterns regardless of the chemical stimulus presented （high spatial neophobia） and that those from a low-predation-risk stream were only risk-averse when the foraging arenas were paired with conspecific alarm cue （lower spatial neophobia）. Those tested in the intermediate- predation-risk stream were consistently intermediate to the high-risk vs. low-risk populations. Our study suggests that ambient predation risk shapes both neophobic predator avoidance and space-use pat- terns and that neophobia may function as a ＂generalized＂ response to ecological uncertainty.

关键词： phenotypic plasticity predator recognition foraging predator recognition predator-prey interactions Trinidadian guppies.

Numerical Analysis of Microchannels Designed for Heat Sinks

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Nanomanufacturing and Metrology 2022年第4期5卷 354-369页

作者： matthew McCormack Fengzhou Fang Jufan Zhang Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) School of Mechanical&Materials EngineeringUniversity College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin300072China

Conjugate heat transfer is numerically investigated using a three-dimensional computational fluid dynamics approach in various microchannel geometries to identify a high-performance cooling method for piezoelectric ceramic stacks and spindle units in high-precision *** microchannels with rectangular cross sections are first considered,showing the performance limitations of decreasing the size of the microchannels,so other solutions are needed for high applied heat ***,many microchannel designs,focusing on streamwise geometric variation,are compared to straight channels to assess their *** varying channels produce the highest heat transfer rates of those ***,their optimization is considered at a channel width and height of 35 and 100μm,*** transfer increases as the amplitude and spatial frequencies of the channels increase due to increased interfacial surface area and enhanced Dean *** highest performance efficiencies are observed at intermediate levels of amplitude and frequency,with efficiency decreasing as these geometric parameters are increased further at the onset of flow *** sinusoidal channel geometries are then optimized with respect to minimizing the system’s pressure drop for all applied heat fluxes between 5690 and 6510 kW/*** so created an optimal geometry curve and showed that all geometries in this region had amplitudes close to 40μ***,imposing a fixed heat flux requirement for a case study of cooling piezoelectric ceramics,the optimized sinusoidal geometry decreases the system pressure drop by 79%relative to a straight channel while maintaining a larger minimum feature size.

关键词： Microchannel Heat sink Conjugate heat transfer Numerical simulation

Biotin biosynthesis in Mycobacterium tuberculosis: physiology, biochemistry and molecular intervention

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Protein & Cell 2011年第9期2卷 691-695页

作者： Wanisa Salaemae Al Azhar grant W.Booker Steven W.Polyak School of Molecular and Biomedical Sciences University of AdelaideSouth Australia 5005Australia

Biotin is an important micronutrient that serves as an essential enzyme *** obtain biotin either through de novo synthesis or by active uptake from exogenous *** are unusual amongst bacteria in that their primary source of biotin is through de novo *** we review the importance of biotin biosynthesis in the lifecycle of *** screens designed to identify key metabolic processes have highlighted a role for the biotin biosynthesis in bacilli growth,infection and survival during the latency *** studies help to establish the biotin biosynthetic pathway as a potential drug target for new anti-tuberculosis agents.

关键词： synthesis. phase. synthesis