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The benefits of being dominant:health correlates of male social rank and age in a marmot

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Current Zoology 2022年第1期68卷 19-26页

作者： Kenta UCHIDA Rachel NG Samuel A.VYDRO Jennifer e.SMITH daniel T.BLUMSTeIN Department of ecology&evolutionary Biology University of CaliforniaLos AngelesCA 90095-1606USA Department of Biology Mills CollegeOaklandCA 94613USA The Rocky Mountain Biological Laboratory Crested ButteCO 81224USA

The benefits of dominance may not come without costs,particularly for *** example,the“immunocompetence handicap hypothesis”states that males with enhanced mating success allocate resources to enhance reproductive output at a cost to their current health,whereas the“resource quality hypothesis”predicts that high-ranking males may benefit from increased reproduction and good *** the predictions from each have been well tested in captive animals and in a variety of highly social primates,fewer studies have been carried out in free-living,facultatively social *** adult male yellow-bellied marmots(Marmota flaviventer),we evaluated predictions of these hypotheses by examining the relationship between social rank and 2 health indicators—fecal glucocorticoid metabolite(FCM)levels,and neutrophil/lymphocyte(N/L)ratios—after accounting for variation explained by age,body mass,and *** found that higher-ranking males tended to have a lower N/L ratio(reflecting good health)than lower-ranking individuals,whereas FCM levels were not significantly related to *** addition,heavier male marmots had lower N/L ratios,whereas body mass was not associated with FCM *** also found that older adult males had lower FCM levels(reflecting less physiological stress)but higher N/L ratios than younger ***,we found that FCM levels decreased as the active season progressed and FCM levels were associated with the time of the ***,our results suggest that socially-dominant male marmots enjoyed better,not worse health in terms of lower N/L ratios.

关键词： immunocompetence handicap hypothesis life history trade-offs N/L ratio physiological stress resource quality hypothesis

Agroecosystem modeling of reactive nitrogen emissions from *** soils with carbon amendments

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Biochar 2023年第1期5卷 1243-1258页

作者： Lina Luo daniel S.Cohan Caroline A.Masiello Taras e.Lychuk Xiaodong Gao Department of Civil and environmental engineering Rice UniversityHoustonTX 77005USA Department of earth Environmentaland Planetary SciencesRice UniversityHoustonTX 77005USA Agriculture and Agri-Food Canada Brandon Research and Development CenterBrandonMB R7A 5Y3Canada

Fertilizer-intensive agriculture is a leading source of reactive nitrogen(Nr)emissions that damage climate,air quality,and human *** has long been studied as a soil amendment,but its influence on Nr emissions remains insufficiently *** recently,the pyrolysis of light hydrocarbons has been suggested as a source of hydrogen fuel,resulting in a solid zero-valent carbon(ZVC)byproduct whose impact on soil emissions has yet to be *** incorporate carbon amendment algorithms into an agroecosystem model to simulate emission changes in the year following the application of biochar or ZVC to the *** *** simulations predicted that the impacts of biochar amendments on Nr emissions would vary widely(−17%to+27%under 5 ton ha^(−1) applications,−38%to+18%under 20 ton ha^(−1) applications)and depend mostly on how nitrification is ***-dose biochar application(5 ton ha^(−1))stimulated emissions of all three nitrogen species in 75%of simulated agricultural areas,while high-dose applications(20 ton ha^(−1))mitigated emissions in 76%of simulated *** zero-valent carbon at 20 ton ha^(−1) exhibited similar effects on nitrogen emissions as biochar applications at 5 ton ha^(−1).Biochar amendments are most likely to mitigate emissions if applied at high rates in acidic soils(pHen(ere the application of carbon amendments would most likely mitigate Nr emissions and their associated adverse impacts.

关键词： Agricultural nitrogen emissions Nitric oxide(NO) Ammonia(NH_(3)) Nitrous oxide(N_(2)O) Biochar Zerovalent carbon(ZVC)

effect of carcass contamination on necrophagous invertebrate performance

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ecological Processes 2021年第1期10卷 795-803页

作者： ellard R.Hunting Maarten Schrama daniel e.Rozen Christina Joenssen Nadja R.Brun Institute of environmental Sciences Leiden UniversityLeidenThe Netherlands. School of Biological Sciences University of BristolBristolUK. Naturalis Biodiversity Centre LeidenThe Netherlands. Institute of Biology Leiden UniversityLeidenThe Netherlands. Current Address:Department of Biological Sciences University of BergenBergenNorway

Background:The breakdown of dead organic matter is driven by a diverse array of organisms and is an important process increasingly impacted by a range of *** many studies have documented how contaminants affect food webs that are fueled by decaying plant litters,much less is known about how contaminants affect organisms that rely on dead animal ***,we begin to explore the effects of food contamination—using silver nanoparticles(AgNPs)as a model contaminant—on the carrion beetle Nicrophorus vespilloides that buries carcasses of small vertebrates in soils as food source and larval nursing ***:Our data show that a single ingestion of a non-lethal dose of 1μg mL^(−1) AgNPs by adult female beetles does not affect overall gut microbial activity but results in shifts in the gut microbial community composition towards pathogens including Alcaligenes,Morganella,and *** no effects were observed in offspring clutch size,some reductions were visible in clutch weight,number of larvae,and number of eclosing pupae in exposed *** in comparison with *** ingestion of AgNPs over several weeks led to a decrease in survival of adult beetles,suggesting that more environmentally realistic exposure scenarios can directly affect the success of carcass-feeding ***:Sub-lethal carcass contamination with a model pollutant can affect the gut microbial composition in female beetles and reduce offspring *** encourages consideration of currently overlooked propagation routes of contaminants through necrophagous food webs and inherent consequences for ecological and evolutionary processes.

关键词： Gut microbiome Maternal transfer Offspring fitness DeCOTAB Nanoparticles Bactericidal compounds Carrion beetle Nicrophorus vespilloides

Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

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Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin G.Willson Lauren e.Cox Justin L.Hart daniel C.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Department of environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an eF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba L.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,ped that understory light penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

MNIST Handwritten Digit Classification Based on Convolutional Neural Network with Hyperparameter Optimization

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Intelligent Automation & Soft Computing 2023年第6期36卷 3595-3606页

作者： Haijian Shao edwin Ma Ming Zhu Xing Deng Shengjie Zhai Department of electrical and Computer engineering University of Nevada Las VegasLas Vegas89154NVUSA ed W.Clark High School Las Vegas89102NVUSA School of Computer Jiangsu University of Science and TechnologyZhenjiang212003China

Accurate handwriting recognition has been a challenging computer vision problem,because static feature analysis of the text pictures is often inade-quate to account for high variance in handwriting styles across people and poor image quality of the handwritten ***,by introducing machine learning,especially convolutional neural networks(CNNs),the recognition accuracy of various handwriting patterns is steadily *** this paper,a deep CNN model is developed to further improve the recognition rate of the MNIST hand-written digit dataset with a fast-converging rate in *** proposed model comes with a multi-layer deep arrange structure,including 3 convolution and acti-vation layers for feature extraction and 2 fully connected layers(i.e.,dense layers)for *** model’s hyperparameters,such as the batch sizes,kernel sizes,batch normalization,activation function,and learning rate are optimized to enhance the recognition *** average classification accuracy of the proposed methodology is found to reach 99.82%on the training dataset and 99.40%on the testing dataset,making it a nearly error-free system for MNIST recognition.

关键词： MNIST dataset deep learning convolutional neural network handwriting recognition

Lineament analysis as a seismic precursor:The el Mayor Cucapah earthquake of April 4,2010(MW7.2),Baja California,Mexico

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Geodesy and Geodynamics 2023年第2期14卷 121-129页

作者： Rosendo Romero-Andrade Manuel e.Trejo-Soto Karan Nayak daniel Hernández-Andrade Naccieli Bojorquez-Pacheco Faculty of earth and Space Sciences Autonomous University of Sinaloa80013Culiacan RosalesSinaloaMexico

An earthquake called the MW7.2“el Mayor Cucapah”earthquake on April 4,2010 has been analyzed for seismic *** changes in the lineament system concerning its pattern and time intervals were analyzed during the earthquake preparation period and occurrence using the automated lineament detection *** Landsat 5 TM images were processed using LeSSA and ADALGeO software obtaining similar *** statistical analysis revealed the stress accumulation due to plate interaction during earthquake *** study shows that the number of extracted lineaments changes rapidly about 23 months before the earthquake,and the systems return to the initial stage after 23 *** lineaments coincide with the extension of the San Andreas Fault as NW direction is the dominant ***,it can be concluded that the featural changes within the Rose diagram corresponding to the different strokes direction along with oriented elongation lines as disclosed in the present study using satellite images could be identified as a mid-term and/or short-term precursors of the ***,even though the dynamism of the el Mayor Cucapah earthquake is found in the extracted lineaments,it is possible to isolate more significant earthquakes even if new ones appear near the ***,using two algorithms for lineament detection allows for the tectonics to corroborate the obtained lineaments and dynamism.

关键词： Lineament analysis earthquake Landsat images Seismic precursor

Vacuum promotes metabolic shifts and increases biogenic hydrogen production in dark fermentation systems

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Frontiers of environmental Science & engineering 2016年第3期10卷 513-521页

作者： Haifa RAJHI daniel PUYOL Mirna C. MARTiNeZ emiliano e. DLAZ Jose L. SANZ Department of Molecular Biology University Autonoma of Madrid Madrid 28049 Spain Section of Chemical engineering University Autonoma of Madrid Madrid 28049 Spain MYGeN Laboratory Cantoblanco Madrid 28049 Spain

The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater （four synthetic media, two industrial waste- water, and one domestic effluent） and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogen-producing bacteria, such as Clostridium, and promoted the dominance of acetoclasticover hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the COD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields.

关键词： dark fermentation biohydrogen wastewaters vacuum

Six forests in one:Tree species diversity in the Bosque Protector Chongón Colonche,a lowland mountain range in coastal ecuadorian

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Forest ecosystems 2022年第6期9卷 725-733页

作者： Oswaldo Jadan David ADonoso edwin Ponce-Ramírez Franz Pucha-Cofrep Omar Cabrera Facultad de Ciencias Agropecuarias Universidad de Cuenca12 de Octubre y Diego de TapiaCuenca010107Ecuador Programa de Doctorado en Conservacion de Recursos Naturales Escuela Internacional de DoctoradoUniversidad Rey Juan CarlosMostolesMadridES-28933Spain Departamento de Biología Escuela Politecnica NacionalLadron de Guevara E11⋅253Quito170525Ecuador Geoforest S.A 12 de febrero y Av.Franklin VegaMacas140150Ecuador Grupo de Investigacion Hidrología y Climatología Universidad Tecnica Particular de LojaSan Cayetano Alto S/NLoja110101Ecuador Brandenburg University of Technology(BTU)Cottbus-Senftenberg 03044CottbusGermany Departamento de Ciencias Biologicas y Agropecuarias Universidad Tecnica Particular de LojaSan Cayetano Alto S/NLoja110101Ecuador

Tropical mountain ranges shape the structure of tree communities and promote highly diverse natural ***“Bosque Protector Chong on-Colonche”(BPCC),an 86,000-ha mountain formation situated on the coast of ecuador,is biogeographically important for the region by connecting floristic elements of the wet Choco and the dry Tumbesian *** understanding of the factors that model tree and palm diversity and distribution in this mountain range are *** measured and identified all trees and palms(DBH≥10 cm)in 289 plots of0.2 ha,distributed throughout *** used generalized linear models to explain the relationship between forest diversity and structure and climatic variables(temperature,rain,aridity),and *** then used cluster and non-metric multidimensional scale(NMDS)analyses to search for distinct forest communities within the *** partition(varpart)was used to determine which predictor variables best explained these distinct forest communities.A species indicator analysis identified the species most likely to define these distinct forest ***,we carried out a niche modeling approach to identify the potential distribution of these forest communities within *** total,we identified 220 tree and palm species in our *** average number of species per plot was 17.8±5.8,ranging from 3 to 40 *** methods sorted the 289study plots into six different forest communities,three communities in the dry forest and three in the semi-humid Garúa *** and temperature,but not altitude or aridity,explained floristic *** results emphasize the high but little cataloged diversity in the lowland mountain rainforests of coastal ecuador.

关键词： Chongón-Colonche Climatic variables Dry forest Forest communities Garúa forest

Cdc42 regulates the cellular localization of Cdc42ep1 in controlling neural crest cell migration

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Journal of Molecular Cell Biology 2018年第5期10卷 376-387页

作者： Shlomi Cohen daniel T. Kovari Wenbin Wei Rebecca Keate Jennifer e. Curtis Shuyi Nie School of Biological Sciences Georgia institute of Technology Atlanta GA 30332 USA School of Physics Georgia Institute of Technology Atlanta GA 30332 USA Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA 30332 USA Department of Physics Emory University Atlanta GA 30322 USA Wallace H. Coulter Department of Biomedical engineering Georgia institute of Technology Atlanta GA 30332 USA

The member of Rho family of small GTPases Cdc42 plays important and conserved roles in cell polarity and motility. The Cdc42ep family proteins have been identified to bind to Cdc42, yet how they interact with Cdc42 to regulate cell migration remains to be elucidated. In this study, we focus on Cdc42epl, which is expressed predominantly in the highly migratory neural crest ceils in frog embryos. Through morpholino-mediated knockdown, we show that Cdc42epl is required for the migration of cranial neural crest cells. Loss of Cdc42epl leads to rounder cell shapes and the formation of membrane blebs, consistent with the observed disruption in actin organization and focal adhesion alignment. As a result, Cdc42ep1 is critical for neural crest cells to apply traction forces at the correct place to migrate efficiently. We further show that Cdc42ep1 is localized to two areas in neural crest celts： in membrane protrusions together with Cdc42 and in perinuciear patches where Cdc42 is absent. Cdc42 directly interacts with Cdc42epl （through the CRIB domain） and changes in Cdc42 level shift the distribution of Cdc42epl between these two subcellular locations, controlling the formation of membrane protrusions and directionality of migration as a consequence. These results suggest that Cdc42ep1 elaborates Cdc42 activity in neural crest cells to promote their efficient migration.

关键词： actin cytoskeleton neural crest Rho GTPases Cdc42 effector protein 1 cell migration