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Olfaction and reaction: The role of olfactory and hypothalamic investment in the antipredator responses to chemical alarm cues by northern redbelly dace

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Current Zoology 2023年第6期69卷 738-746页

作者： brendan J.Joyce Grant E.Brown Department of Biology Concordia UniversityMontrealQuebecCanada

Neuroplasticity enables teleosts to promote or downregulate the growth of their brains *** compensate for the effects of predation pressure,teleosts may alter their brain morphology and behavioral responses to mitigate its impact on individual ***-predation environ-ments often promote specific patterns of brain growth and produce bolder and more proactive *** to the expense of maintaining neural tissue,relative size indicates the regions most relied *** northern redbelly dace Chrosomus eos,as little as 2 weeks of elevated predation pressure,resulted in increased investment in their olfactory bulbs and optic tecta,while the imposition of captivity produced smaller,less symmetric *** together,these results suggest that an individual could potentially become better able to detect a threat,and simultaneously less inclined to react to it,making the impact of either change in isolation is difficult to ***,we compared interindividual variation in gross brain morphology,risk-taking tactics in a novel arena(shy-bold personality),and responding to olfactory cues(proactive/reac-tive stress-coping style).We hypothesized that olfactory investment would positively correlate with response intensity to predator cue concen-tration and respond across a wider range of cue concentrations,while hypothalamus size would correlate with shyness and *** to heightened risk produced more bold/proactive individuals,with larger olfactory bulbs and smaller ***,the direction of the correlation between hypothalamus size and behavior varied by treatment,and olfactory investment only corresponded with response intensity amongst proactive *** findings illustrate the potential pitfalls of relating gross brain morphology to complex behavior and suggest that stress-coping style is a relevant consideration in future studies.

关键词： boldness brainmorphology neuroplasticity predation proactivity stress-coping style

Speculations on the mechanisms for the formation and breakup of supercontinents

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Geoscience Frontiers 2013年第2期4卷 185-194页

作者： J.brendan Murphy R.Damian Nance Department of Earth Sciences.St.Francis Xavier University Antigonish.Nova Scotia B2G 2W5Canada Department of Geological Sciences Ohio UniversityAthensOH 45701USA

The supercontinent cycle has had a profound effect on the Earth＇s evolution since the Late Archean but our understanding of the forces responsible for its operation remains *** appear to form by two end-member processes：extroversion,in which the oceanic lithosphere surrounding the supercontinent（exterior ocean） is preferentially subducted（***）,and introversion in which the oceanic lithosphere formed between dispersing fragments of the previous supercontinent（interior ocean） is preferentially subducted（***）.Extroversion can be explained by ＂top-down＂ geodynamics, in which a supercontinent breaks up over a geoid high and amalgamates above a geoid low. Introversion,on the other hand,requires that the combined forces of slab-pull and ridge push（which operate in concert after supercontinent break-up） must be overcome in order to enable the previously dispersing continents to turn *** may begin when subduction zones are initiated along boundaries between the interior and exterior oceans and become trapped within the interior *** speculate that the reversal in continental motion required for introversion may be induced by slab avalanche events that trigger the rise of superplumes from the core-mantle boundary.

关键词： Supercontinent cycle Introversion Extroversion Pangea Rodinia Pannotia

Origins of the supercontinent cycle

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Geoscience Frontiers 2013年第4期4卷 439-448页

作者： R.Damian Nance J.brendan Murphy Department of Geological Sciences.316 Clippinger Laboratories.Ohio University.Athens.OH 45701.USA Department of Earth Sciences st.Francis Xavier UniversityAntigonishNova Scotia B2G 2W5.Canada

The supercontinent cycle, by which Earth history is seen as having been punctuated by the episodic assembly and breakup of supercontinents, has influenced the rock record more than any other geologic phenomena, and its recognition is arguably the most important advance in Earth Science since plate tectonics. It documents fundamental aspects of the planet＇s interior dynamics and has charted the course of Earth＇s tectonic, climatic and biogeochemical evolution for billions of years. But while the widespread realization of the importance of supercontinents in Earth history is a relatively recent development, the supercontinent cycle was first proposed thirty years ago and episodicity in tectonic processes was recognized long before plate tectonics provided a potential explanation for its occurrence. With interest in the supercontinent cycle gaining momentum and the literature expanding rapidly, it is instructive to recall the historical context from which the concept developed. Here we examine the supercontinent cycle from this perspective by tracing its development from the early recognition of long-term epi- sodicity in tectonic processes, through the identification of tectonic cycles following the advent of plate tectonics, to the first realization that these phenomena were the manifestation of episodic superconti- nent assembly and breakup.

关键词： Supercontinent cyclePlate tectonicsTectonic episodicitySecular trends

Understanding Performance for Two 802.11 Competing Flows

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Journal of Computer Science & Technology 2008年第3期23卷 365-376页

作者： Michael J.Feeley brendan Cully Sharath J.George Department of Computer Science University of British ColumbiaVanconverCanada

It is well known that 802.11 suffers from both inefficiency and unfairness in the face of competition and interference. This paper provides a detailed analysis of the impact of topology and traffic type on network performance when two flows compete with each other for airspace. We consider both TCP and UDP flows and a comprehensive set of node topologies. We vary these topologies to consider all combinations of the following four node-to-node interactions：（1） nodes unable to read or sense each other, （2） nodes able to sense each other but not able to read each other＇s packets and nodes able to communicate with （3） weak and with （4） strong signal. We evaluate all possible cases through simulation and show that the cases can be reduced to 9 UDP and 10 TCP 802.11g models with similar efficiency/fairness characteristics. We also validate our simulation results with extensive experiments conducted in a laboratory testbed. These more detailed models improve on previous work such as hidden-/exposed-terminal categorization and are thus better suited as a basis for adaptive techniques to improve performance in 802.11 multi-hop WLAN or Mesh Networks.

关键词： 802.11 wireless unfairness two-flow competition network topology

Geotechnical investigation of low-plasticity organic soil treated with nano-calcium carbonate

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第2期15卷 500-509页

作者： Govindarajan Kannan brendan C.O’Kelly Evangelin Ramani Sujatha Centre for Advanced Research in Environment School of Civil EngineeringSASTRA Deemed to be UniversityThanjavurTamil Nadu613401India Department of Civil Structural and Environmental EngineeringTrinity College DublinDublinD02 PN40Ireland

Soil stabilization using nanomaterials is an emerging research area although,to date,its investigation has mostly been laboratory-based and therefore requires extensive study for transfer to practical field *** present study advocates nano-calcium carbonate(NCC)material,a relatively unexplored nanomaterial additive,for stabilization of low-plasticity fine-grained soil having moderate organic *** plasticity index,compaction,unconfined compressive strength(UCS),compressibility and permeability characteristics of the 0.2%,0.4%,0.6%and 0.8%NCC-treated soil,and untreated soil(as control),were determined,including investigations of the effect of up to 90-d curing on the UCS and permeability *** terms of UCS improvement,0.4%NCC addition was identified as the optimum dosage,mobilizing a UCS at 90-d curing of almost twice that for the untreated *** treated soil,particle aggregation arising from NCC addition initially produced an increase in the permeability coef-ficient,but its magnitude decreased for increased curing owing to calcium silicate hydrate(CSH)gel formation,although still remaining higher compared to the untreated soil for all dosages and curing periods *** index decreased for all NCC-treated soil *** micro-graphs indicated the presence of gel patches along with particle aggregation.X-ray diffraction(XRD)results showed the presence of hydration products,such as *** increases in UCS are initially attributed to void filling and then because of CSH gel formation with increased curing.

关键词： Organic silt Calcium carbonate Nano-calcium carbonate(NCC) Calcium silicate hydrate(CSH) Soil stabilization

Adherence to surveillance endoscopy following hospitalization for index esophageal variceal hemorrhage

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World Journal of Gastrointestinal Surgery 2018年第4期10卷 40-48页

作者： brendan T Everett Steven D Lidofsky Gastroenterology and Hepatology Unit University of Vermont Medical Center

AIM To investigate patient adherence to surveillance endoscopy after index esophageal variceal hemorrhage and the extent to which adherence influences *** We reviewed the records of patients with cirrhosis admitted to the medical intensive care unit between 2000 and 2014 for first time esophageal variceal hemorrhage treated with endoscopic variceal ligation who were subsequently discharged and scheduled for surveillance endoscopy at our medical center. Demographic and clinical data were obtained through the medical records, including etiology of cirrhosis, completion of variceal obliteration, attendance at surveillance endoscopy, zip code of primary residence, distance from home to hospital, insurance status, rehospitalization for variceal hemorrhage, beta-blocker at discharge, pharmacologically treated psychiatric disorder, and transplant free survival. RESULTS Of 99 consecutive survivors of esophageal variceal bleeding, the minority(33) completed variceal obliteration and fewer(12) adhered to annual surveillance. Completion of variceal obliteration was associated with fewer rehospitalizations for variceal rebleeding(27% vs 56%, P = 0.0099) and when rehospitalizations occurred, they occurred later in those who had completed obliteration(median 259 d vs 207 d, P = 0.0083). Incomplete adherence to endoscopic surveillance was associated with more rehospitalizations for variceal rebleeding compared to those fully adherent to annual endoscopic surveillance(51% vs 17%, P = 0.0328). Those adherent to annual surveillance were more likely to be insured privately or through Medicare compared to those who did not attend post-hospital discharge endoscopy(100% vs 63%, P = 0.0119).CONCLUSION Most patients do not complete variceal obliteration after index esophageal variceal hemorrhage and fewer adhere to endoscopic surveillance, particularly the uninsured and those insured with Medicaid.

关键词： Liver cirrhosis Endoscopy Esophageal varices Secondary prevention Patient adherence

Intermittent swelling and shrinkage of a highly expansive soil treated with polyacrylamide

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 252-261页

作者： Amin Soltani An Deng Abbas Taheri brendan C.O’Kelly School of Engineering Information Technology and Physical SciencesFederation UniversityChurchillVIC3842Australia School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaideSA5005Australia Department of Civil Structural and Environmental EngineeringTrinity College DublinDublinD02 PN40Ireland

This laboratory study examines the potential use of an anionic polyacrylamide(PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South *** experimental program consisted of consistency limits,sediment volume,compaction and oedometer cyclic swell-shrink tests,performed using distilled water and four different PAM-to-water solutions of P_(D)=0.1 g/L,0.2 g/L,0.4 g/L and 0.6 g/L as the mixing ***,the relative swelling and shrinkage strains were found to decrease with increasing number of applied swell-shrink cycles,with an‘elastic equilibrium’condition achieved on the conclusion of four *** propensity for swelling/shrinkage potential reduction(for any given cycle)was found to be in favor of increasing the PAM dosage up to P_(D)=0.2 g/L,beyond which the excess PAM molecules self-associate as aggregates,thereby functioning as a lubricant instead of a flocculant;this critical dosage was termed‘maximum flocculation dosage’(MFD).The MFD assertion was discussed and validated using the consistency limits and sediment volume properties,both exhibiting only marginal variations beyond the identified MFD of P_(D)=0.2 g/*** accumulated axial strain progressively transitioned from‘expansive’for the unamended soil to an ideal‘neutral’state at the MFD,while higher dosages demonstrated undesirable‘contractive’states.

关键词： Expansive soil Polyacrylamide(PAM) Consistency limits Sediment volume Swell-shrink cycles Swelling and shrinkage strains Accumulated axial strain

Mice Deficient in NF-κB p50 and p52 or RANK Have Defective Growth Plate Formation and Post-natal Dwarfism

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Bone Research 2013年第4期1卷 336-345页

作者： Lianping Xing Di Chen brendan F.Boyce Department of Pathology and Laboratory Medicine University of Rochester Medical Center Department of Biochemistry Rush University Medical Center

NF-κBp50/p52 double knockout （dKO） and RANK KO mice have no osteoclasts and develop severe osteopetrosis associated with dwarfism. In contrast, Op/Op mice, which form few osteoclasts, and Src KO mice, which have osteoclasts with defective resorptive function, are osteopetrotic, but they are not dwarfed. Here, we compared the morphologic features of long bones from p50/p52 dKO, RANK KO, Op/Op and Src KO mice to attempt to explain the differences in their long bone lengths. We found that growth plates in p50/p52 dKO and RANK KO mice are significantly thicker than those in WT mice due to a 2-3-fold increase in the hypertrophic chondrocyte zone associated with normal a proliferative chondrocyte zone. This growth plate abnormality disappears when animals become older, but their dwarfism persists. Op/Op or Src KO mice have relatively normal growth plate morphology. In-situ hybridization study of long bones from pS0/ p52 dKO mice showed marked thickening of the growth plate region containing type 10 collagen-expressing chondrocytes. Treatment of micro-mass chondrocyte cultures with RANKL did not affect expression levels of type 2 collagen and Sox9, markers for proliferative chondrocytes, but RANKL reduced the number of type 10 collagen-expressing hypertrophic chondrocytes. Thus, RANK/NF-κB signaling plays a regulatory role in post-natal endochondral ossification that maintains hypertrophic conversion and prevents dwarfism in normal mice.

关键词： NF-κB RANK growth plate chondrocytes dwarfism

Consideration of corneal biomechanics in the diagnosis and management of keratoconus: is it important?

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Eye and Vision 2016年第1期3卷 141-146页

作者： FangJun Bao brendan Geraghty QinMei Wang Ahmed Elsheikh The Affiliated Eye Hospital of Wenzhou Medical University Wenzhou City 325027China The Institution of Ocular Biomechanics Wenzhou Medical UniversityWenzhou City 325027China School of Engineering University of LiverpoolLiverpool City L693GHUK NIHR Biomedical Research Centre for Ophthalmology Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of OphthalmologyLondon CityUK

Keratoconus is a bilateral,non-inflammatory,degenerative corneal *** occurrence and development of keratoconus is associated with corneal thinning and conical protrusion,which causes irregular *** the disruption of the collagen organization,the cornea loses its shape and function resulting in progressive visual ***,corneal topography is the most important tool for the diagnosis of keratoconus,which may lead to false negatives among the patient population in the subclinical ***,it is now hypothesised that biomechanical destabilisation of the cornea may take place ahead of the topographic evidence of keratoconus,hence possibly assisting with disease diagnosis and *** article provides a review of the definition,diagnosis,and management strategies for keratoconus based on corneal biomechanics.

关键词： Keratoconus In vivo Corneal biomechanics Corneal collagen cross-linking