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Microgeographic Variation and Inter-Riffle Migration of <i>Rhinichthys atratulus</i>(Pisces: Cyprinidae) in a Small Connecticut Stream, United States

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Open j.urnal of Ecology 2020年第7期10卷 460-481页

作者： sage j. loomis Kayla Anatone Laura Bither Sarah j. Kang Nola Neri David Machado Michelle L. Kraczkowski Barry Chernoff College of the Environment Wesleyan University Middletown USA Department of Biology Wesleyan University Middletown USA Department of Molecular Biology and Biochemistry Wesleyan University Middletown USA Department of Biology University of Saint Joseph West Hartford USA Department of Earth & Environmental Sciences Wesleyan University Middletown USA

We examined the genetic diversity on a microgeographic scale of Rhinichthys atratulus (Eastern Blacknose Dace) in Allyn Brook, a small tributary in the upper Coginchaug River drainage in Connecticut. By looking at gene flow on a microgeographic scale among populations that had no physical barriers to migration, we tested the null hypothesis that the populations should be homogeneous. We resolved seven polymorphic microsatellite loci and one mitochondrial gene, nd2, in three adj.cent populations (5 km) in the Coginchaug River. A dam from the 1920’s in lower Allyn Brook has isolated Allyn-Brook populations from Coginchaug-River populations. Allyn Brook was selected because there are only three riffle habitats in the brook and, therefore, there can be no immigration from upstream populations. Each population has private (i.e., unique) alleles and haplotypes, and there are significant genetic differences between all sites. The Allyn Brook populations are almost as different from one another as they are from the distant populations in the Coginchaug River from which they have been isolated for more than 80 years. These results point to in situ evolution and little migration or gene flow among populations on a microgeographic scale. This raises interesting questions for conservation of genetic diversity of stream fishes.

关键词： Migration Microgeographic Differentiation Population Ecology Gene Flow Rhinichthys atratulus

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Invading from the garden？ A comparison of leaf herbivory for exotic and native plants in natural and ornamental settings

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Insect Science 2012年第6期19卷 677-682页

作者： Stephen F. Matter j.ssica R.Brzyski Christopher j. Harrison Sara Hyams Clement Loo j.ssica loomis Hannah R. Lubbers Leeann Seastrum Trevor I. Stamper Adam M. Stein Richard Stokes Brandy S. Wilkerson Department of Biological Sciences University of Cincinnati Cincinnati USA

The enemies release hypothesis proposes that exotic species can become in- vasive by escaping from predators and parasites in their novel environment. Agrawal et al. （Enemy release？ An experiment with congeneric plant pairs and diverse above- and below-ground enemies. Ecology, 86, 2979-2989） proposed that areas or times in which damage to introduced species is low provide opportunities for the invasion of native habitat. We tested whether ornamental settings may provide areas with low levels of herbivory for trees and shrubs, potentially facilitating invasion success. First, we compared levels of leaf herbivory among native and exotic species in ornamental and natural settings in Cincinnati, Ohio, United States. In the second study, we compared levels of herbivory for invasive and noninvasive exotic species between natural and ornamental settings. We found lower levels of leaf damage for exotic species than for native species; however, we found no differences in the amount of leaf damage suffered in ornamental or natural settings. Our results do not provide any evidence that ornamental settings afford additional release from herbivory for exotic plant species.

关键词： enemies release hypothesis forest herbivory host plant suburban urban

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Using cylindrical implosions to investigate hydrodynamic instabilities in convergent geometry

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Matter and Radiation at Extremes 2019年第6期4卷 13-21页

作者： j.P.Sauppe S.Palaniyappan E.N.loomis j.L.Kline K.A.Flippo B.Srinivasan Los Alamos National Laboratory P.O.Box 1663Los AlamosNew Mexico 87545USA Virginia Polytechnic Institute and State University BlacksburgVirginia 24061USA

Hydrodynamic instabilities such as the Rayleigh–Taylor(RT)and Richtmyer–Meshkov instabilities disrupt inertial confinement fusion(ICF)implosions through the growth of 3D *** of these 3D imperfections at the interfaces of an ICF capsule during implosion lead to mixing between materials that is detrimental to *** instabilities have been studied extensively in planar geometry,but such experiments lack the effects of convergence in spherical *** several studies have been performed in spherical geometry,these often lack a direct means to measure perturbation *** in cylindrical geometry include convergence effects while maintaining direct diagnostic *** cylinders have less compression than spheres,they do provide an excellent platform to validate modeling for convergent *** problem with previous cylindrical implosion experiments was that the convergence ratios were limited to∼*** the National Ignition Facility(NIF),larger cylindrical targets can be driven to convergences of 10–15 while maintaining a large enough final diameter to measure perturbation *** paper reviews the design process used to both benchmark radiation hydrodynamics codes and enable 1D post-processed simulations to explore design space to separate compression effects from acceleration/deceleration RT *** from 1D simulations suggest that cylindrical implosions on the NIF can produce high-convergence experiments to validate RT instability growth for ICF implosions.

关键词： cylindrical geometry convergent

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Transient and etiology-related transcription regulation in cirrhosis prior to hepatocellular carcinoma occurrence

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World j.urnal of Gastroenterology 2009年第3期15卷 300-309页

作者： Frédérique Caillot Céline Derambure Paulette Bioulac-sage Arnaud Franois Michel Scotte Odile Goria Martine Hiron Maryvonne Daveau j.an-Philippe Salier Inserm Unité 905 and Institut Fédératif de Recherches Multidisciplinaires sur les Peptides Faculté de Médecine-Pharmacie76183 RouenFrance Service d'Anatomie Pathologique Centre Hospitalier Universitaireand Inserm U88933000 BordeauxFrance Département Pathologie Centre Hospitalier Universitaire76183 RouenFrance Service de Chirurgie Générale et Digestive Centre Hospitalier Universitaire76183 RouenFrance Service d'Hépato-gastro-entérologie Centre Hospitalier Universitaire76183 RouenFrance

AIM： To search for transcription dysregulation that could （1） differentiate hepatocellular carcinoma （HCC）-free from HCC-related cirrhosis （2） differentiate HCC-free cirrhosis related to HCV from that related to alcohol intake. METHODS： Using microarray analysis, we compared transcript levels in HCC-free cirrhosis （alcoholism： 7; hepatitis C： 7）, HCC-associated cirrhosis （alcoholism： 10; hepatitis C： 10） and eight control livers. The identified transcripts were validated by qRT-PCR in an independent cohort of 45 samples （20 HCC-free cirrhosis; 15 HCC-associated cirrhosis and 10 control livers）. We also confirmed our results by ***： In HCC-free livers, we identified 70transcripts which differentiated between alcoholicrelated-cirrhosis, HCV-related cirrhosis and control livers. They mainly corresponded to down-regulation. Dysregulation of Signal Transduction and Activator of Transcription-3 （STAT-3） was found along with related changes in STAT-3 targets which occurred in an etiology-dependent fashion in HCC-free cirrhosis. In contrast, in HCC, such transcription dysregulations were not observed. CONCLUSION： We report that transcriptional dysregulations exist in HCC-free cirrhosis, are transiently observed prior to detectable HCC onset and may be appear like markers from cirrhosis to HCC transition.

关键词： Liver Pathology Alcoholism Hepatitis Cvirus Gene expression Carcinogenesis

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Scales of snow depth variability in high elevation rangeland sagebrush

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Frontiers of Earth Science 2017年第3期11卷 469-481页

作者： Molly E. TEDESCHE Steven R. FASSNACHT Paul j. MEIMAN Watershed Science Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80523-1476 USA Intemational Arctic Research Center Water & Environmental Research Center Institute of Northern Engineering University of Alaska Fairbanks Fairbanks AK 99775 USA Cooperative Institute for Research in the Atmosphere Fort Collins CO 80523-1375 USA Natural Resources Ecology Laboratory Fort Collins CO 80523-1499 USA Abt. Kartographie GIS & Femerkundung Geographisches Institut Georg-August-Universitat Gottingen 37077 Gottingen Germany Rangeland Ecosystem Science Department of Forest and Rangeland Stewardship Colorado State University Fort Collins CO 80523 USA

In high elevation semi-arid rangelands, sage- brush and other shrubs can affect transport and deposition of wind-blown snow, enabling the formation of snowdrifts. Datasets from three field experiments were used to investigate the scales of spatial variability of snow depth around big mountain sagebrush （Artemisia tridentata Nutt.） at a high elevation plateau rangeland in North Park, Colorado, during the winters of 2002, 2003, and 2008. Data were collected at multiple resolutions （0.05 to 25 m） and extents （2 to 1000 m）. Finer scale data were collected specifically for this study to examine the correlation between snow depth; sagebrush microtopogra- phy, the ground surface, and the snow surface, as well as the temporal consistency of snow depth patterns. Vario- grams were used to identify the spatial structure and the Moran＇s I statistic was used to determine the spatial correlation. Results show some temporal consistency in snow depth at several scales. Plot scale snow depth variability is partly a function of the nature of individual shrubs, as there is some correlation between the spatial structure of snow depth and sagebrush, as well as between the ground and snow depth. The optimal sampling resolution appears to be 25-cm, but over a large area, this would require a multitude of samples, and thus a random stratified approach is recommended with a fine measurement resolution of 5-cm.

关键词： snow hydrology high elevation rangelands,spatial statistics variograms snow pack spatial variability,snow drifts

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Controlling the gelation temperature of biomimetic polyisocyanides

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Chinese Chemical Letters 2018年第2期29卷 281-284页

作者： Paul H.j. Kouwer Paula de Almeida Onno ven den Boomen Zaskia H. Eksteen-Akeroyd Roel Hammink Maarten j.spers Stij. Kragt Mathij. F.j. Mabesoone Roelandj.M. Nolte Alan E. Rowan Martin G.T.A. Rutten Vincent A.A. Le sage Daniel C. Schoenmakers Chengfen Xing j.aliang xu Institute for Molecules and Materials Radboud University Nijmegen 6525 A J The Netherlands

Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature（LCST） is often sharp, which allows for a wide range of smart material *** the LCST, oligo（ethylene glycol）-substituted polyisocyanides（PICs） form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol（EG） tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.

关键词： Smart materials Lower critical solution temperature Polyisocyanides Mechanical properties Biomimetic polymers

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