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Habitat structure directly affects aggression in convict cichlids Archocentrus nigrofasciatus

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Current Zoology 2010年第1期56卷 52-56页

作者： Anthony j. BARLEY ronald M. COLEMAN Department of Biological Sciences California State University Sacramento California 95819-6077 USA

Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water temperature and resource levels. In this study, we tested if the amount of habitat structure in the environment affected aggression levels in female convict cichlids Archocentrus nigrofasciatus. We performed a laboratory experiment in which we placed female convict cichlids into an aquarium with low or high amounts of habitat structure and monitored the dominant female＇s behavior toward the subordinate female. Aggressive behavior in convict cichlids primarily consists of chases and bites. We found that the total time the dominant female spent chasing the subordinate female was greater when there was a low amount of habitat structure as compared to when there was a high amount of habitat structure. We also found that both the average duration of a chasing bout and the number of bites directed at the subordinate fish increased when there was a low amount of structure, but the number of chases did not. These results indicate that increased habitat structural complexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].

关键词： Neotropical Life-history Female-female competition Fish Resource competition

Applying rock mass classifications to carbonate rocks for engineering purposes with a new approach using the rock engineering system

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j.urnal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 364-369页

作者： Gioacchino Francesco Andriani Mario parise Dipartimento di Scienze della Terra e Geoambientali Università degli Studi di Bari Aldo MoroVia E. Orabona n. 4Bari 70125Italy

Classical rock mass classification systems are not applicable to carbonate rocks,especially when these are affected by karst *** applications to such settings could therefore result in outcomes not representative of the real stress-strain *** this study,we propose a new classification of carbonate rock masses for engineering purposes,by adapting the rock engineering system(RES) method by Hudson for fractured and karstified rock masses,in order to highlight the problems of implementation of geomechanical models to carbonate *** new approach allows a less rigid classification for carbonate rock masses,taking into account the local properties of the outcrops,the site conditions and the type of engineering work as well.

关键词： Rock mass classification Carbonates Karst Rock engineering system(RES)

A pancreatic player in dementia:pathological role for islet amyloid polypeptide accumulation in the brain

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Neural Regeneration Research 2023年第10期18卷 2141-2146页

作者： Angelina S.Bortoletto ronald j.Parchem Center for Cell and Gene Therapy Stem Cell and Regenerative Medicine CenterDepartment of NeuroscienceDepartment of Molecular and Cellular BiologyTranslational Biology and Molecular Medicine ProgramMedical Scientist Training ProgramBaylor College of MedicineHoustonTXUSA

Type 2 diabetes mellitus patients have a markedly higher risk of developing *** multiple factors contribute to this predisposition,one of these involves the increased secretion of amylin,or islet amyloid polypeptide,that accompanies the pathophysiology of type 2 diabetes *** amyloid polypeptide accumulation has undoubtedly been implicated in various forms of dementia,including Alzheimer’s disease and vascular dementia,but the exact mechanisms underlying islet amyloid polypeptide’s causative role in dementia are *** this review,we have summarized the literature supporting the various mechanisms by which islet amyloid polypeptide accumulation may cause neuronal damage,ultimately leading to the clinical symptoms of *** discuss the evidence for islet amyloid polypeptide deposition in the brain,islet amyloid polypeptide interaction with other amyloids implicated in neurodegeneration,neuroinflammation caused by islet amyloid polypeptide deposition,vascular damage induced by islet amyloid polypeptide accumulation,and islet amyloid polypeptide-induced *** are very few therapies approved for the treatment of dementia,and of these,clinical responses have been controversial at ***,investigating new,targetable pathways is vital for identifying novel therapeutic strategies for treating *** such,we conclude this review by discussing islet amyloid polypeptide accumulation as a potential therapeutic target not only in treating type 2 diabetes mellitus but as a future target in treating or even preventing dementia associated with type 2 diabetes mellitus.

关键词： Alzheimer’s disease amylin amyloid dementia diabetes human islet amyloid polypeptide islet amyloid polypeptide protofibrils type 2 diabetes mellitus vascular dementia

Environment-dependent attack rates of cryptic and aposematic butterflies

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Current Zoology 2018年第5期64卷 663-669页

作者： Brett M. SEYMOURE Andrew RAYMUNDO Kevin j. MCGRAW W. OWEN MCMILLAN ronald L, RUTOWSKI Department of Biology Colorado State University Fort Collins CO 80523 USA School of Life Sciences Arizona State University Tempe AZ 85287 USA Smithsonian Tropical Research Institute Panama City Panama

Many organisms have evolved adaptive coloration that reduces their risk of predation. Cryptic colo- ration reduces the likelihood of detection/recognition by potential predators, while warning or aposematic coloration advertises unprofitability and thereby reduces the likelihood of attack. Although some studies show that aposematic coloration functions better at decreasing attack rate than crypsis, recent work has suggested and demonstrated that crypsis and aposematism are both successful strategies for avoiding predation. Furthermore, the visual environment （e.g., ambient lighting, background） affects the ability for predators to detect prey. We investigated these 2 related hypoth- eses using 2 well-known visually aposematic species of Heliconius butterflies, which occupy differ- ent habitats （open-canopy vs. closed-canopy）, and one palatable, cryptic, generalist species j.nonia coenia. We tested if the differently colored butterflies differ in attack rates by placing plasti- cine models of each of the 3 species in 2 different tropical habitats where the butterflies naturally occur： disturbed, open-canopy habitat and forested, closed-canopy habitat. The cryptic model had fewer attacks than one of the aposematic models. Predation rates differed between the 2 habitats, with the open habitat having much higher predation. However, we did not find an interaction between species and habitat type, which is perplexing due to the different aposematic phenotypes naturally occurring in different habitats. Our findings suggest that during the Panamanian dry sea- son avian predation on perched butterflies is not a leading cause in habitat segregation between the 2 aposematic species and demonstrate that cryptically colored animals at rest may be better than aposematic prey at avoiding avian attacks in certain environments.

关键词： avian attacks camouflage Heliconius j.nonia light environment plasticine models predation warning coloration.

A novel ZnO/reduced graphene oxide and Prussian blue modified carbon paste electrode for the sensitive determination of Rutin

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Science China Chemistry 2019年第2期62卷 262-270页

作者： Ozma j.D'Souza ronald j.Mascarenhas Ashis K Satpati Basavanakote M Basavaraj. Research and Development Centre Bharathiar University Electrochemistry Research Group Department of Chemistry St.Joseph's College Analytical Chemistry Division Bhabha Atomic Research Centre Anushakthi Nagar Trombay Department of Chemistry PES University

A carbon paste modified sensor based on a novel composite of zinc oxide nanoparticles deposited on reduced graphene oxide(ZnO-rGrO) and Prussian blue(PB) was drop-cast(ZnO-rGrO-PB/MCPE) for the sensitive estimation of Rutin(Rtn) at pH *** high surface area of ZnO-rGrO and electrocatalytic property of PB promotes the oxidation of Rtn. Field emission scanning electron microscope(FE-SEM) and energy-dispersive X-ray spectroscopy(EDX) techniques were employed to confirm the deposition of ZnO-rGrO and PB on carbon paste electrode(CPE). The ability of ZnO-rGrO-PB/MCPE in charge transfer at the interface was investigated using electrochemical impedance spectroscopy(EIS). The heterogeneous rate constant(ks) and the charge transfer coefficient(α) have been calculated as 6.08 s^(-1) and 0.74 respectively. This sensor showed a wide linear response for Rtn from 7.0×10^(-8)to 7.0×10^(-6) M and 7.0×10^(-6) to 1.0×10^(-4) M with a limit of detection(2.05±0.04)×10^(-8) M(S/N=3). The application of ZnO-rGrO-PB/MCPE was found in the analysis of Rtn in fruit j.ice samples using standard addition method. This sensor showed good reproducibility, stability, selectivity and sensitivity.

关键词： Rutin zinc oxide nanoparticles reduced graphene oxide Prussian blue modified carbon paste electrode ascorbic acid

Using Inductance as a Tuning Parameter for RF Meta-atoms

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Nano-Micro Letters 2012年第2期4卷 103-109页

作者： Derrick Langley ronald A.Coutu Peter j.Collins Air Force Institute of Technology Wright-Patterson Air Force Base

The resonant frequency of metamaterials structured with split ring resonator(SRR) meta-atoms is determined primarily through the capacitance and inductance of the individual meta-atoms. Two designs that vary inductance incrementally were modeled, simulated, fabricated, and tested to investigate the role inductance plays in metamaterial designs. The designs consisted of strategically adding sections to the SRR to increase the inductance, but in a manner that minimized capacitance variations. Each design showed a shift in resonant frequency that was proportional to the length of the added section. As the length of each section was increased, the resonant frequency shifted from 2.78 GHz to 2.18 GHz.

关键词： Inductance Meta-atom Metamaterial Split Ring Resonator Radio Frequency Resonance

Variation and mechanisms of clastic reservoir quality in the Paleogene Shahej.e Formation of the Dongying Sag, Bohai Bay Basin, China

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Petroleum Science 2014年第2期11卷 200-210页

作者： Zhang Qin Zhu Xiaomin ronald j.Steel Zhong Dakang College of Geosciences China University of Petroleum State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Department of Geological Sciences The University of Texas at Austin

Reservoir quality varies greatly in the Shahej.e Formation in the Dongying Sag. It is essential to analyze the variation and mechanisms of reservoir quality for determining the controlling factors based on cores, porosity measurements and fluid inclusion techniques and so on. The sandstones in the fluvial, （fan） delta-front have the best reservoir quality due to the depositional conditions mechanically controlling the petrology configuration and the primary porosity, and chemically influencing the diagenesis and development of secondary pores. The activity of the boundary faults and the sedimentary facies dominate the variation of reservoir quality in different areas and intervals. The reservoir quality varies with the position of sandstone beds in different vertical models of sandstone and mudstone. This mainly arose from the strong cementation or strong dissolution in the sandstone caused by the diagenesis evolution of adj.cent mudstone. With higher oil saturation reservoir quality is better because the hydrocarbon charge favors dissolution and restricts cementation. Diagenesis, depositional conditions and tectonic setting are the key controls of reservoir quality in the Shahej.e Formation of the Dongying Sag.

关键词： Reservoir quality variation clastic reservoir quality hydrocarbon charge vertical models ofsandstone and mudstone controlling factor

Calibrated dilatometer exercise to probe thermoplastic properties of coal in pressurized CO2

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International j.urnal of Coal Science & Technology 2017年第3期4卷 245-251页

作者： Vyacheslav N. Romanov ronald j. Lynn Robert P. Warzinski U. S. Department of Energy National Energy TechnologyLaboratory P. O. Box 10940 Pittsburgh PA 15236 USA

This research was aimed at testing a hypothesis, that at elevated CO2 pressure coal can soften at temperatures well below those obtained in the presence of other gases. That could have serious negative implications for inj.ction of CO2 into deep coal seams. We have examined the experimental design issues and procedures used in the previously published studies, and experimentally investigated the physical behavior of a similar coal in the presence of COa as a function of pressure and temperature, using the same high-pressure micro-dilatometer refurbished and carefully calibrated for this purpose. No notable reduction in coal softening temperature was observed in this study.

关键词： Dilatometry · Carbon dioxide· Coal· Plasticization

Experiences Analyzing Faults in a Hybrid Distributed System with Access Only to Sanitized Data

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j.urnal of Software Engineering and Applications 2010年第5期3卷 446-454页

作者： ronald j. Leach Department of Systems & Computer Science Howard University Washington DC USA.

In this paper we report on a work in progress assessing the faults observed and reported in a distributed, safety-critical, largely embedded system with both electrical and mechanical components. We illustrate why standard software testing techniques are not sufficient and indicate some of the technical and non-technical problems encountered in examining the faults and the initial results obtained. While the application domain is elevator operation, the techniques described here are general enough to apply to many other domains. Much of the data analyzed here would be considered imprecise in the software industry if it were used in software testing or to help increase fault tolerance. The paper includes a discussion of the use of multiple views of data, assessment of missing data, and analysis of informal information to produce its conclusions about fault avoidance and fault tolerance.

关键词： Distributed System Safety-Critical Systems Fault Tolerance Remote Monitoring