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Relating environmental variables with aquatic community structure in an agricultural/urban coldwater stream

Ecological Processes 2021年第1期10卷 481-499页

作者： daniel T.l.Myers Richard R.Rediske james N.McNair Aaron d.Parker E.Wendy Ogilvie Annis Water Resources Institute Grand Valley State University740 W Shoreline DriveMuskegonMI 49401USA. Michigan department of Environment Great Lakesand Energy525 W Allegan StreetLansingMI 48909USA. Grand Valley Metropolitan Council 678 Front Avenue NWSuite 200Grand RapidsMI 49504USA.

Background:Urban areas are often built along large rivers and surrounded by agricultural *** may lead to small tributary streams that have agricultural headwaters and urbanized lower *** study objectives assessed are as follows:(1)landscape,geomorphic,and water quality variables that best explained variation in aquatic communities and their integrity in a stream system following this agricultural-to-urban land use gradient;(2)ways this land use gradient caused aquatic communities to differ from what would be expected for an idealized natural stream or other longitudinal gradients;and(3)whether the impacts of this land use gradient on aquatic communities would grow larger in a downstream direction through the agricultural and urban *** study area was an impaired coldwater stream in Michigan,***:Many factors structured the biological communities along the agricultural-to-urban land use *** woody debris had the strongest relationship with EPT(Ephemeroptera,Plecoptera,and Trichoptera)abundance and richness and were most common in the lower,urbanized *** streambed substrate had the strongest relationship with diptera taxa and surface air breather macroinvertebrates and was dominant in agricultural *** community assemblage was influenced largely by stream flow and temperature regimes,while poor fish community integrity in lower urban reaches could be impacted by geomorphology and episodic urban pollution *** macroinvertebrates were most abundant in deforested,first-order agricultural headwaters,while EPT macroinvertebrate richness was the highest downstream of agricultural areas within the urban zone that had extensive forest ***:Environmental variables and aquatic communities would often not conform with what we would expect from an idealized natural *** richness improved downstream of agricultural *** shows promise for the recovery of aquatic systems using we

关键词： land use Habitat Stream Fish Macroinvertebrate Gradient

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Prospects for detecting ultra-high-energy particles with FAST

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Research in Astronomy and Astrophysics 2019年第2期19卷 25-38页

作者： Clancy W.james Justin d.Bray Ronald d.Ekers International Centre for Radio Astronomy Research Curtin University School of Physics & Astronomy University of Manchester CSIRO Astronomy & Space Science

The origin of the highest-energy particles in nature, ultra-high-energy(UHE) cosmic rays, is still unknown. In order to resolve this mystery, very large detectors are required to probe the low flux of these particles — or to detect the as-yet unobserved flux of UHE neutrinos predicted from their interactions. The‘lunar Askaryan technique' is a method to do both. When energetic particles interact in a dense medium,the Askaryan effect produces intense coherent pulses of radiation in the MHz–GHz range. By using radio telescopes to observe the Moon and look for nanosecond pulses, the entire visible lunar surface(20 million km^2) can be used as a UHE particle detector. A large effective area over a broad bandwidth is the primary telescope requirement for lunar observations, which makes large single-aperture instruments such as the Five-hundred-meter Aperture Spherical radio Telescope(FAST) well-suited to the technique. In this contribution, we describe the lunar Askaryan technique and its unique observational requirements. Estimates of the sensitivity of FAST to both the UHE cosmic ray and neutrino flux are given, and we describe the methods by which lunar observations with FAST, particularly if equipped with a broadband phased-array feed, could detect the flux of UHE cosmic rays.

关键词： cosmic rays neutrinos techniques:miscellaneous Moon

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Role of calpain system in meat tenderness: A review

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Food Science and Human Wellness 2018年第3期7卷 196-204页

作者： Z.F.Bhat james d.Morton Susan l.Mason Alaa El-din A.Bekhit department of Wine Food and Molecular Biosciences Faculty of Agriculture and Life SciencesLincoln UniversityLincoln7647ChristchurchNew Zealand department of Food Sciences University of OtagoP.O.Box 56Dunedin 9054New Zealand

Aging is a popular method used by meat industry for improving the sensory attributes of *** the advent of many novel technologies,aging has not lost its charm and is still widely used commercially as a post-mortem intervention for *** improves the tenderness of meat through disruption of the muscle structure by intracellular proteolytic *** undergo various molecular changes that cause proteolysis of key myofibrillar and cytoskeletal proteins,disrupting the overall integrity of muscle *** several endogenous proteolytic systems are capable of post-mortem proteolysis,a great body of scientific evidence supports a major role for the calpain *** are intracellular calcium-dependent cysteine proteases found in most *** least three calpains(μ-and m-calpains and calpain 3)and calpastatin,their specific endogenous inhibitor,are found in *** are known to be involved in the proteolysis of functionally relevant structural proteins such as the myofibrillar proteins and cytoskeletal anchorage *** ubiquitous proteases are also present in mitochondria and play important roles in a variety of pathophysiological conditions including apoptotic and necrotic cell death *** review discusses the role and contribution of the calpain system and the factors that influence calpain activity during aging.

关键词： Aging Tenderness Calpains Proteolysis Calpain activity Factors

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Effect of nanoparticles on the nucleation and agglomeration rates of hydrate growth using THF-water clathrates

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Petroleum Science 2020年第2期17卷 467-476页

作者： Syed Y.Nahri james l.Nielsen Yuanhang Chen Craft and Hawkins department of Petroleum Engineering Louisiana State UniversityBaton RougeLA 70803USA

Four types of nanoparticles,amorphous carbon,ironⅢoxide,SiO2,and amino-coated SiO2,were tested to determine changes in tetrahydrofuran-water(THF-water)clathrate hydrate nucleation and *** were experimentally found to determine their viability for preventing natural gas hydrates from developing during offshore drilling ***-water clathrates were chosen as a model to represent gas hydrate growth at atmospheric *** of each nanoparticle between 0.15%and 1.0%by weight were tested as a kinetic inhibitor to hydrate *** were repeated at various temperatures below the formation temperature of 4.4℃for THF-water clathrate *** were made to identify how the concentration of THF affects the clathrate hydrates forming under static conditions between20%and 30%by mole of *** primary tests in this study were performed using a 20:80 THF/water *** increases during hydrate nucleation for THF-water were measured between-5 and 3℃.The range of ideal nanoparticle concentrations was found to be between 0.15%and 0.45%by weight for optimal static,kinetic inhibition of hydrate *** approximately 0.3%by weight,the most significant inhibition was observed under static conditions for all four types of nanoparticles *** found that functionalized amino-coated SiO2 nanoparticles,across all tests,significantly increased the time required for the formation of THF-water clathrate hydrates compared to the other three non-functionalized *** amorphous carbon and ironⅢoxide nanoparticles performed similarly across each test and were both the least effective in their inhibition of the clathrate hydrates of the four nanoparticles studied compared to a control.

关键词： Nanoparticles Gas hydrates Clathrates Hydrate inhibition Functionalized nanoparticles

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Upper range limit establishment after wildfire of an obligateseeding montane forest tree fails to keep pace with 20th century warming

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Journal of Plant Ecology 2018年第2期11卷 200-207页

作者： John W.Morgan james d.Vincent james S.Camac Research Centre for Applied Alpine Ecology Department of EcologyEnvironment and EvolutionLa Trobe UniversityKingsbury DriveBundooraVIC 3086Australia department of Biological Sciences Macquarie UniversityBalaclava RoadNorth RydeNew South Wales 2109Australia

Aims How species respond to climate change at local scales will depend on how edaphic and biological characteristics interact with species physiological limits and traits such as *** seeders,those species that depend on fire for recruitment,have few and epi-sodic opportunities to track a changing climate *** such cases,long-distance seed dispersal will be necessary to take advan-tage of rare recruitment *** examine recruitment patterns and seedling growth below,at and above the timberline of an obligate-seeding Australian montane forest tree(Eucalyptus delegatensis)after stand-replacing fire,and place these changes in the context of regional *** We use two methods to detect whether *** can estab-lish and persist above the timberline after stand-replacing wildfire in montane forests in south-east ***,we examine estab-lishment patterns by using belt transects at six sites to quantify how changes in post-fire recruit density with increasing distance above the timberline seven years ***,to determine whether dispersal or physiological constraints determine post-fire establish-ment patterns,we transplanted seedlings and saplings into bare ground above(100 m elevation),at,and below(50 m elevation)timberline 18-months after *** monitored seedling growth and survival for one growing *** Findings There was minimal upslope migration of the species after fire with most saplings observed near seed-bearing timberline trees,with only occasional outpost *** seedlings and saplings sur-vived equally well across one growing season when planted above existing timberlines,relative to saplings at or below the *** and sapling growth rates also did not differ across these location,although seedlings grew at much faster rates than *** findings suggest that upslope growing season conditions are unlikely to limit initial range expansion of trees aft

关键词： climate change dispersal limitation growth rates regeneration niche timberline

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Oviposition Site Preference and Its Effects on Subsequent development of Variegated Grasshopper (Zonocerus variegatus l.) under laboratory Conditions

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Advances in Entomology 2024年第3期12卷 143-154页

作者： Saffea Joseph Torto Abu james Sundufu Alusaine Edward Samura Sahr Ngoba Fomba dennis Peter Musa Skeku Alfred Kanu Prince Emmanuel Norman department of Crop Protection School of Agriculture and Food Sciences Njala Sierra Leone department of Horticulture School of Natural Resources Management Njala University Njala Sierra Leone department of Crop Science School of Agriculture and Food Sciences Njala University Njala Sierra Leone Germplasm Enhancement and Seeds Systems Sierra Leone Agricultural Research Institute Freetown Sierra Leone

Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus l.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra leone during 2022/2023. The treatments comprised three soil types (Sandy, loamy and Clay), each with three replications laid out in a randomized complete block design (RCBd) in wooden cages. data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), doubling time (dt), and overall survivorship. Findings revealed that, Z. variegatus l. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.

关键词： development Oviposition Oviposition Site Preference Soil Types Variegated Grasshopper

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Western Imperialism and Military Reform in Japan and China

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Frontiers of History in China 2012年第3期7卷 404-414页

作者： james l. Hevia department of History The University of Chicago Chicago IL 60637 USA

This paper compares the initial efforts at military reform in China and Japan in the late nineteenth century. Changes in military organization and training are situated within a global process of military transformation represented by changes in the structure of the Prussian army. The Prussian staff system and planning program were imported into both Japan and China, but with quite different results. The paper contrasts centralization and standardization as typified by the new Japanese army with the decentered approaches in China. The paper argues that although there was substantive change in China, the Qing state was unable to impose a uniform plan for military Westernization. As a result, the new armies were never integrated into a common organization capable of defending the state from external aggression.

关键词： Prussian military model General Staff army reform Japan armyreform China drill and maneuvers arsenals Indian Army Intelligence Branch,centralized military planning

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Real-time Object Subspace Searching Based on discrete Searching Paths and local Energy

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International Journal of Automation and computing 2016年第2期13卷 99-107页

作者： Wen-Ju Zhou Zi-Xiang Fei Huo-Sheng Hu li liu Jing-Na li Peter james smith School of Computer Science and Electronic Engineering University of Essex Colchester CO4 3SQ UK School of Information and Electronic Engineering Ludong University Yantai 264025 China Vitec Videocom ltd Bury St Edmunds Suffolk IP33 3TB UK

In automatic visual inspection, the object image subspace should be segmented and matched quickly so that the affine relationship can be built between the template image and the sample image. When the interference is strong and the illumination is uneven, for example in an industrial application, this can make it difficult to obtain an objects subspace quickly and accurately in real-time. In this paper, a novel strategy is proposed to adopt discrete radial search paths instead of searching all points in an image. Therefore, the searching time can be substantially reduced. In order to reduce the influence coming from the industrial environment, the paper proposes another method that is local energy level set segmentation, which can locate the object subspace more efficiently and accurately. The detection of ＂crown caps＂ is presented as an example in this paper. detection effects and computing time are compared between several detection methods, and the mechanisms of inspection have also been analyzed.

关键词： Real-time object subspace discrete paths fast match level set local energy function

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Response of saproxylic insect communities to logging history, tree species, stage of decay, and wood posture in the central Nearctic boreal forest

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Journal of Forestry Research 2018年第5期29卷 1365-1377页

作者： R.W.james dennis Jay R.Malcolm Sandy M.smith M.Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks St.Toronto ON M5S 3B3 Canada departamento de Ecología Genética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and IEGEBA (CONICET)Buenos Aires Argentina

Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest *** used a split-plot ANOVA design to analyze differences in selected saproxylic insects（all arthropod orders and dipteran and parasitic hymenopteran families） emerging from dead wood of sites with different logging histories（horse-logged,mechanically-logged and unlogged）,tree species（Populus and Picea）,stage of decay（early-and late-decay stages） and posture（standing and downed logs） in the boreal forest of central *** clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was *** consistently emerged more from Populus than from Picea dead *** of the studied saproxylic families were more abundant in late-decay than in early-decay *** of the Cecidomyiidae,Ceratopogonidae,Empididae,Mycetophilidae and Sciaridae families,and hymenopterans of the diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead *** contrast,Mymaridae was most abundant in standing dead *** study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.

关键词： Boreal forest dead wood quality Forest harvesting High-level taxa Saproxylic insects

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Mechanistic insights into the novel glucose-sensitive behavior of P(NIPAM-co-2-AAPBA)

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Science China Chemistry 2020年第3期63卷 377-385页

作者： Qingxian Wang Mian Fu Ying Guan Tony d.james Yongjun Zhang Key laboratory of Functional Polymer Materials and State Key laboratory of Medicinal Chemical Biology Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China department of Chemistry University of BathClaverton DownBath BA27AYUK

A glucose-sensitive polymer,poly(N-isopropylacrylamide-co-2-acrylamidophenylboronic acid)(P(NIPAM-co-2-AAPBA)),was synthesized by reversible addition fragmentation chain transfer(RAFT)*** of glucose results in reduced solubility and hence increased turbidity,rather than the normal increase in solubility(decreased turbidity)observed for other PBA-based glucose-sensitive *** novel glucose-sensitive behavior is explained by a new mechanism,in which glucose acts as an additive and depresses the lower critical solution temperature(lCST)of the polymer,instead of increasing solubility by increasing the degree of ionization of the PBA *** and theoretic analysis for the influence of glucose on the thermal behavior of P(NIPAM-co-2-AAPBA)reveals that glucose depresses the lCST of P(NIPAM-co-2-AAPBA)copolymers in a two-stage manner,a fast decrease at low glucose concentrations followed by a slow decrease at high glucose *** low glucose concentrations,the binding of glucose with PBA groups on the polymer chain increases the number of glucose molecules proximal to the polymer which influences the thermal behavior of the polymer,causing a rapid decrease in ***,the transition occurs at a glucose concentration equal to the reciprocal of the binding constant between PBA and glucose,thus providing a novel method to determine the binding *** saccharides,including mannose,galactose and fructose,also depress the lCST of P(NIPAM-co-2-AAPBA)copolymer in the same way.

关键词： glucose-sensitive mechanism phenylboronic acid thermosensitive binding constant lower critical solution temperature polymers

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