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Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terj. Gobakken Svetlana Saarela Henrik j.Persson Magnus Ekstrom Sean P.Healey Zhiqiang Yang j.han Holmgren Eva Lindberg Kenneth Nystrom Emanuele Papucci Patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson ronald E.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adj.stments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

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

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.

NON-DESTRUCTIVE ANALYSIS OF THE NUCLEI OF TRANSGENIC LIVING CELLS USING LASER TWEEZERS AND NEAR-INFRARED RAMAN SPECTROSCOPIC TECHNIQUE

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Genomics, Proteomics & Bioinformatics 2005年第3期3卷 169-178页

作者： Wei Tang ronald j. Newton Chang-An Xie Yong-Qing Li Nicki Whitley Department of Biology Howell Science Complex East Carolina UniversityGreenville NC 27858-4353 USA. Department of Physics Howell Science Complex East Carolina University Greenville NC 27858-4353 USA.

Transgenic cell lines of loblolly pine （Pinus taeda L.） were analyzed by a compact laser-tweezers-Raman-spectroscopy （LTRS） system in this investigation. A low power diode laser at 785 nm was used for both laser optical trapping of single transgenic cells and excitation for near-infrared Raman spectroscopy of the nuclei of synchronized cells, which were treated as single organic particles, at the S-phase of the cell cycle. Transgenic living cells with gfp and uidA genes were used as biological samples to test this LTRS technique. As expected, different Raman spectra were observed from the tested biological samples. This technique provides a high sensitivity and enables real-time spectroscopic measurements of transgenic cell lines. It could be a valuable tool for the study of the fundamental cell and molecular biological process by trapping single nucleus and by providing a wealth of molecular information about the nuclei of cells.

关键词： transgenic cell laser optical trapping near-infrared Raman spectroscopy biological sample

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

Behaviors that predict personality components in adult free-ranging Tibetan macaques Macaca thibetana

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Current Zoology 2014年第3期60卷 362-372页

作者： Alexander j. PRITCHARD Lori K. SHEERAN Kara I. GABRIEL j.n-Hua LI ronald S. WAGNER Department of Anthropology Rutgers University New Brunswick NJ 08901 USA Department of Anthropology Central Washington University Ellensburg WA 98926 USA Department of Psychology Central Washington University Ellensburg WA 98926 USA School of Resource and Environmental Engineering Anhui University Hefei 230601 China School of Life Science Anhui Normal University Hefei 230601 China Department of Biology Central Washington University Ellensburg WA 98926 USA

To further the potential for applied personality studies, we present a methodology for assessing personality in nonhu man animals without a priori assumptions, using behavioral measures to discriminate personality survey results. Our study group consisted of 12 freeranging, provisioned, adult Tibetan macaques Macaca thibetana at the Valley of the Wild Monkeys, China. We asked familiar Chinese park guards and scientists to rate each of the 12 macaques using 27item personality surveys. We also recorded behavioral observations （〉 100 hrs） from AugustSeptember, 2012. The personality surveys showed reliability in 22 of the items that were then utilized in a principal component analysis that revealed five components： Insecurity, Reactivity, Boldness, Sociability, and Leadership. Prior personality research on Macaca show comparable components. In order to determine which behaviors would best predict those five personality components, we conducted discriminant analyses using behavioral measures as predictors. We found that behavioral measures of avoidance, lunging, feargrinning, selfdirected behaviors, touching, proximity and chasing could significantly predict personality component scores in certain situations. Finally, we analyzed the effects of situation （provisioning and tourists） and found situation influenced proximity and rates of avoidance and selfdirected behaviors. Wider implementation of this methodology may permit longterm analysis of personality using behavioral proxies for established personality traits, in particular on research investigating the effects of tourism and provisioning on personality .

关键词： Tourism Provisioning Temperament Surveys Personality Primate

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