检索结果-南通市图书馆

Behavioral differences within and among populations of an African cichlid found in divergent and extreme environments

引用

Current Zoology 2019年第1期65卷 33-42页

作者： richard C. Oldham Lauren m. Pintor Suzanne m. Gray School of Environment and Natural Resources The Ohio State University Columbus OH 43210 USA

Animals are increasingly faced with human?induced stressors that vary in space and time, thus we can expect populati on-level diverge nee in behaviors that help animals to cope with en vironme ntal change. However, empirical evidenee of behavioral trait divergence across environmental extremes is lacking. We tested for variation in behavioral traits among 2 populations of an African cichlid fish (Pseudocrenilabrus multicolor victoriae Seegers, 1990) that experience extremes of dissolved oxygen (DO) and turbidity and are known to vary in a number of physiological and life history traits associated with these stressors. Using a comm on garden reari ng experime nt, F1 progeny from wild-caught parents originating from a swamp (low DO, clear) and a river (high DO, turbid) were reared in high DO, clear water. Predator simulation assays were conducted to test for (1) variation in boldness, general activity, and foraging activity between populations,(2) differences in correlations betwee n behaviors with in and across populati ons, and (3) repeatability of behaviors. There was strong evide nee for diverge nee betwee n populati ons, with swamp fish being more bold (i.e.z leaving refuge sooner after a simulated predator attack) and active (i.e., spent more time out of refuge) than river fish. Across populations there were positive correlations between foraging activity and both boldness and general activity;however, within populations, there was only a strong positive relationship between foraging activity and boldness in the river population. Here, we have demonstrated that populations that originate from drastically different environments can produce proge ny that exhibit measurable differences in behaviors and their correlated relati on ships eve n whe n reared un der comm on conditions.

关键词： behavioral correlation behavioral syndrome boldness hypoxia pace of life turbidity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Enhanced densification and mechanical properties of β-boron by in-situ formed boron-rich oxide

引用

Journal of materials Science & Technology 2022年第4期99卷 148-160页

作者： Haibo Zhang metin Örnek Simanta Lahkar Shuangxi Song Xiaodong Wang richard A.Haber Kolan madhav Reddy School of materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of materials Science and Engineering RutgersThe State University of New JerseyPiscatawayNJ 08854USA

We report nearly full densification of polycrystalline rhombohedral beta(β)-boron without the addition of sintering aids via spark plasma sintering(SPS).The analytical aberration corrected transmission electron microscope observations have revealed in-situ growth of nanocrystalline boron-rich oxide precipitates that contain approximately 4 at.%of oxygen and beget the densification of β-*** electron energy loss spectroscopy and diffraction analysis confirmed that the newly formed boron-rich oxide(nominally B_(96)O_(4))structure with B-O σ-bonding belongs to space group R■*** sensitive nanoindentation showed boron-rich oxide phase has a hardness of about 41±2 GPa,which is 10%higher than that of β-boron *** estimated hardness and fracture toughness of β-boron were approximately 31 GPa and 2.2 mPa m^(1/2),respectively,using Vickers microindentation,which falls in the range of those commercially used boron *** results suggest that the enhanced densification and mechanical properties arise from the newly formed boron-rich oxide inβ-boron during SPS experiments.

关键词： Boron Precipitates Sintering mechanical properties Transmission electron microscopy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Bathymetry inversion using the deflection of the vertical:A case study in South China Sea

引用

Geodesy and Geodynamics 2022年第5期13卷 492-502页

作者： Xiaoyun Wan Bo Liu Xiaohong Sui richard F.Annan Ruijie Hao Yijun min School of Land Science and Technology China University of Geosciences(Beijing)Beijing 100083China Qian Xuesen Laboratory of Space Technology Beijing 100094China

The deflection of the vertical is one of the essential products of ***,unlike gravity and vertical gravity gradients,it is seldom used in bathymetry *** this study,an algorithm for bathymetry inversion using the deflection of the vertical is ***,we separately derive the formulas for the bathymetry inversion from the north and east components of the vertical deflection and introduce the data *** a local area in the South China Sea is selected as an example to test the *** bathymetry inversion based on gravity anomaly is also conducted for *** the ship-borne depths are the true values,the error standard deviations(STDs)of the bathymetry derived by north and east components of the vertical deflection are 156.64 m and 165.57 m,*** indicates that the north component has a better performance in bathymetry inversion than the east *** inversion results from the combination of both components show a higher accuracy of bathymetry than that from a single *** difference between the error STD of the combination results and that of the gravity anomaly is less than 0.2 *** experiment’s results also show that the precision of the derived bathymetry can be improved if the parameters of linear regression are adjusted according to water *** summary,among the gravity field products used in this study,the gravity anomaly yielded the best performance in the bathymetry ***,since additional data and computation time are required to derive gravity anomalies from altimetric observations,the vertical defections can still be used as supplements,especially in areas where accurate vertical deflections exist.

关键词： Bathymetry Deflection of the vertical Gravity anomaly Satellite altimetry

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Wild dogma： An examination of recent ＂evidence＂ for dingo regulation of invasive mesopredator release in Australia

引用

Current Zoology 2011年第5期57卷 568-583页

作者： Benjamin L. ALLEN richard m. ENGEmAN Lee R. ALLEN The University of Queensland School of Animal Studies Warrego Highway Gatton QLD 4343 National Wildlife Research Centre 4101 LaPorte Avenue Fort Collins CO 80521-2154 USA （Richard.M.Engeman@aphis.usda.gov） Biosecurity Queensland Robert Wicks Pest Animal Research Centre Tor Street Toowoomba QLD 4350 （Lee.Allen@deedi.qld.gov.au）

There is growing interest in the role that apex predators play in shaping terrestrial ecosystems and maintaining trophic cascades. In line with the mesopredator release hypothesis, Australian dingoes (Canis lupus dingoand hybrids) are assumed by many to regulate the abundance of invasive mesopredators, such as red foxesVulpes vulpesand feral catsFelis catus, thereby providing indirect benefits to various threatened vertebrates. Several recent papers have claimed to provide evidence for the biodiversity benefits of dingoes in this way. Nevertheless, in this paper we highlight several critical weaknesses in the methodological approaches used in many of these reports, including lack of consideration for seasonal and habitat differences in activity, the complication of simple track-based indices by incorporating difficult-to-meet assumptions, and a reduction in sensitivity for assessing populations by using binary measures rather than potentially continuous measures. Of the 20 studies reviewed, 15 of them (75%) contained serious methodological flaws, which may partly explain the inconclusive nature of the literature investigating interactions between invasive Australian predators. We therefore assert that most of the “growing body of evidence” for meso-predator release is merely an inconclusive growing body of literature only. We encourage those interested in studying the ecological roles of dingoes relative to invasive mesopredators and native prey species to account for the factors we identify, and caution the value of studies that have not done so.

关键词：澳大利亚侵入证据陆地生态系统狗检查调控野生

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Clinical significance of mesenteric panniculitis-like abnormalities on abdominal computerized tomography in patients with malignant neoplasms

引用

World Journal of Gastroenterology 2016年第48期22卷 10601-10608页

作者： Eli D Ehrenpreis Grigory Roginsky richard m Gore University of Chicago Center for the Study of Complex Diseases Gastroenterology North Shore University Health System Highland Park Hospital Department of Radiology North Shore University HealthS ystem

AIm To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).mETHODS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet(Rad Net Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical *** In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fiftynine patients had mesenteric panniculitis(mP)-like abnormalities on their abdominal CT. Of these patients, 81 patients(22.6%) had a known history of cancer at the time of their CT scan. Nineteen(5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these(14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with mPlike findings on CT(36 cases, 36%), with follicular lymphoma being the most frequent subtype(17/36). A variety of solid tumors, most commonly prostate(7) and renal cell cancers(6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45(80%), worsened in 6(11%), and improved in 5 patients(9%). Positron emission tomography(PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients(5%). CONCLUSION A new diagnosis of cancer is uncommon in patients with CT findings suggestive of mP. mP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.

关键词： Panniculitis Peritoneal X ray Neoplasms Computed tomography Small intestine misty mesentery Lymphoma Tomography Positron emission tomography

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Discrete element simulation of cylindrical particles using super-ellipsoids

引用

Particuology 2019年第5期17卷 55-66页

作者： Yongzhi Zhao Lei Xu Paul B. Umbanhowar richard m. Lueptow Institute of Process Equipment College of Energy Engineering Zhejiang University Hangzhou 310027 China Department of mechanical Engineering Northwestern University Evanston Illinois 60208 USA Department of Chemical and Biological Engineering Northwestern University Evanston. Illinois 60208 USA The Northwestern Institute on Complex Systems (NICO) Northwestern University Evanston Illinois 60208 USA

A discrete element model based on super-ellipsoids was used to simulate cylindrical particle flow. The model can describe a cylindrical particle accurately provided the shape indices of the super-ellipsoids are set to appropriate values. To achieve more rapid calculations, we implemented an "oriented bounding box algorithm"(OBBA) for the initial contact detection of cylindrical particles. Several types of Simulations were performed to validate the super-ellipsoid model and the contact-detection algorithm. First, the effect of shape index of the super-ellipsoids on model accuracy was investigated through three simulations: impact of a cylindrical particle on a flat wall, flow of cylindrical particles in a rotating tumbler, and segregation of cylindrical particles of different length flowing down a bounded heap. The simulation results show that the super-ellipsoids describe cylindrical particles accurately when the shape index that specifies the sharpness of the cylinder edges is sufficiently large. The efficiency of the OBBA is measured by simulations in which a box is filled with cylindrical particles and a tumbler that contains cylindrical particles is rotated. The simulation results show that the OBBA can accelerate the calculations significantly. The effect of particle shape (such as aspect ratio and shape index) on the calculation speed was obtained. The simulation of rod-like particles tended to take more calculation time than that of disk-like particles, and the simulation time increased with an increasing particle-shape index.

关键词： Discrete element method Super-ellipsoid Super-quadric Cylindrical particle Non-spherical particle Granular material

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Quantifying geological uncertainty in metamorphic phase equilibria modelling;a monte Carlo assessment and implications for tectonic interpretations

引用

Geoscience Frontiers 2016年第4期7卷 591-607页

作者： richard m.Palin Owen m.Weller David J.Waters Brendan Dyck Institute of Geosciences Johannes-Gutenberg University Mainz55128MainzGermany Geological Survey of Canada 601 Booth StreetOttawaONKIA OESCanada Department of Earth Sciences University of OxfordOxfordOX1 3ANUnited Kingdom

Pseudosection modelling is rapidly becoming an essential part of a petrologist＇s toolkit and often forms the basis of interpreting the tectonothermal evolution of a rock sample, outcrop, or geological region. Of the several factors that can affect the accuracy and precision of such calculated phase diagrams, ＂geological＂ uncertainty related to natural petrographic variation at the hand sample- and/or thin section-scale is rarely considered. Such uncertainty influences the sample＇s bulk composition, which is the primary control on its equilibrium phase relationships and thus the interpreted pressure-temper- ature （P-T） conditions of formation. Two case study examples--a garnet-cordierite granofels and a garnet-staurolite-kyanite schist--are used to compare the relative importance that geological uncer- tainty has on bulk compositions determined via （1） X-ray fluorescence （XRF） or （2） point counting techniques. We show that only minor mineralogical variation at the thin-section scale propagates through the phase equilibria modelling procedure and affects the absolute P-T conditions at which key assemblages are stable. Absolute displacements of equilibria can approach ＋l kbar for only a moderate degree of modal proportion uncertainty, thus being essentially similar to the magnitudes reported for analytical uncertainties in conventional thermobarometry. Bulk compositions determined from multiple thin sections of a heterogeneous garnet-staurolite-kyanite schist show a wide range in major-element oxides, owing to notable variation in mineral proportions. Pseudosections constructed for individual point count-derived bulks accurately reproduce this variability on a case-by-case basis, though averaged proportions do not correlate with those calculated at equivalent peak P-T conditions for a whole-rock XRF-derived bulk composition. The main discrepancies relate to varying proportions of matrix phases （primarily mica） relative to porphyroblasts （primarily staurolite and kyanit

关键词： Geological uncertainty Error Pseudosection monte Carlo mnNCKFmASHTO

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The effect of EmG magnitude on the masseter vestibular evoked myogenic potential(mVEmP)

引用

Journal of Otology 2022年第4期17卷 203-210页

作者： Daniel J.Romero Gary P.Jacobson richard A.Roberts Department of Hearing and Speech Sciences Division of Vestibular SciencesVanderbilt University Medical Center121521st Ave.South6308 Medical Center EastNashvilleTN37232-8718USA

Introduction:The masseter vestibular evoked myogenic potential(mVEmP)is a bilaterally generated,electromyographically(EmG)-mediated response innervated by the trigeminal *** purpose of the present investigation was to 1)determine whether subjects could accurately achieve and maintain a range of EmG target levels,2)to examine the effects of varied EmG levels on the latencies and amplitudes of the mVEmP,and 3)to investigate the degree of side-to-side asymmetry and any effects of EmG ***:Subjects were nine neurologically and otologically normal young adults.A high-intensity tone burst was presented monaurally while subjects were seated upright and asked to match a range of EmG target levels by clenching their *** were made from the ipsilateral and contralateral masseter muscles referenced to the ear being monaurally ***:We found that the tonic EmG target had no effect on mVEmP ***,although mVEmP amplitudes“scaled”to the EmG target,there was a tendency for the subjects’EmG level to“undershoot”the EmG target levels greater than 50 *** some individuals did generate differences in EmG activation between sides,there were no significant differences on average EmG activation between ***,while average corrected amplitude asymmetry was similar across EmG targets,some individuals demonstrated large,corrected amplitude asymmetry ***:The results of this investigation suggest that,as with cVEmP recordings,the underlying EmG activation may vary between subjects and could impact mVEmP amplitudes,yet could be mitigated by amplitude correction *** it is important to be aware that even young normal subjects have difficulty maintaining large,tonic EmG activity during the mVEmP recording.

关键词： Vestibular evoked myogenic potentials (VEmPs) masseter VEmPs Electromyography(EmG) Vestibulomasseteric reflex(VmR) EmG target Level

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Secular change in earth processes： Preface

引用

Geoscience Frontiers 2018年第4期9卷 965-966页

作者： richard m.Palin Christopher J.Spencer Department of Geology and Geological Engineering Colorado School of Mines Golden CO 80401 USA The Institute of Geoscience Research (TIGER) School of Earth and Planetary Sciences Curtin University WA 6102 Australia

*** Uniformitarianism is a traditional approach used in many areas of geoscience that assumes the geologic processes observed today operated similarly throughout all of Earth history（Hutton,1788;Windley,1993）,with such an ideology commonly encapsulated by the maxim＂the present is the key to the past＂.This concept is closely associated with the philosophical principle of Occam’s razor.

关键词： Secular change in earth processes Preface

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Endoplasmic reticulum stress and liver diseases

引用

Liver Research 2019年第1期3卷 55-64页

作者： Xiaoying Liu richard m.Green Division of Gastroenterology and Hepatology Department of MedicineNorthwestern University Feinberg School of MedicineChicagoILUSA

Endoplasmic reticulum(ER)stress occurs when ER homeostasis is perturbed with accumulation of unfolded/misfolded protein or calcium *** unfolded protein response(UPR),comprising of inositol-requiring enzyme 1 a(IRE1 a),double-stranded RNA-dependent protein kinase(PKR)-like ER kinase(PERK)and activating transcription factor 6(ATF6)signaling pathways,is a protective cellular response activated by ER ***,UPR activation can also induce cell death upon persistent ER *** liver is susceptible to ER stress given its synthetic and other biological *** studies from human liver samples and animal disease models have indicated a crucial role of ER stress and the UPR signaling pathways in the pathogenesis of liver diseases,including non-alcoholic fatty liver disease(NAFLD),alcoholic liver disease(ALD),alpha-1 antitrypsin(AAT)deficiency(AATD),cholestatic liver disease,drug-induced liver injury,ischemia/reperfusion(I/R)injury,viral hepatitis and hepatocel-lular carcinoma(HCC).Extensive investigations have demonstrated the potential underlying mechanisms of the induction of ER stress and the contribution of the UPR pathways during the development of the ***,ER stress and the UPR proteins and genes have become emerging therapeutic targets to treat liver diseases.

关键词： Endoplasmic reticulum(ER)stress Unfolded protein response(UPR) Inositol-requiring enzyme 1 a(IRE1 a) Double-stranded RNA-dependent protein kinase(PKR)-like ER kinase(PERK) Activating transcription factor 6(ATF6) Liver diseases

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：