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Density dependence and habitat preference shape seedling survival in a subtropical forest in central China

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journal of Plant Ecology 2015年第6期8卷 568-577页

作者： junmeng Lu daniel j.johnson Xiujuan Qiao Zhijun Lu Qinggang Wang Mingxi jiang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of Sciences1 Moshan RoadWuhanHubei 430074China Department of Life Science University of Chinese Academy of Sciences19A YuQuan RoadBeijing 100049China School of Forestry and Environmental Studies Yale University195 Prospect StreetNew HavenCT 06511USA

Aims seedlings are vulnerable to many kinds of fatal abiotic and biotic agents,and examining the causes of seedling dynamics can help understand mechanisms of species *** disentangle the relative importance of neighborhood densities,habitat factors and phylogenetic relatedness on focal seedling survival,we monitored the survival of 5306 seedlings of 104 species>15 *** address the following questions:(i)How do neighborhood densities,habitat variables and phylogenetic relatedness affect seedling survival?What is the relative importance of conspecific densities,habitat variables and phylogenetic relatedness to seedling survival?(ii)Does the importance of the neighborhood densities,habitat variables and phylogenetic relatedness vary among growth forms,leaf habits or dispersal modes?specially,does the conspecific negative density dependence inhibit tree and decidu-ous seedlings more compared with shrub and evergreen species?Does density dependence affect the wind and animal-dispersed species equally?Methods We established 135 census stations to monitor seedling dynamics in a 25-ha subtropical forest plot in central *** and heterospecific seedling density in the 1-m2 seedling plot and adult basal area within a 20-m radius provided neighborhood density *** elevation,convexity and aspect of every 5-×5-m grid with seedling plots were used to quantify habitat *** calculated the relative average phylodiversity between focal seed-ling and heterospecific neighbors to quantify the species related-ness in the *** candidate generalized linear mixed models with binominal error distribution were used to compare the relative importance of these variables to seedling ***’s information criteria were used to identify the most parsimonious *** Findingsat the community level,both the neighborhood densities and phylogenetic relatedness were important to seedling *** found negative effec

关键词： generalized linear mixed models negative density dependence niche partitioning phylodiversity seedling dynamics species coexistence

Male and female meadow voles Microtus pennsylvanicus respond differently to scent marks from the top- middle-, and bottom-scent donors of an over-mark

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Current Zoology 2011年第4期57卷 441-448页

作者： Michael H. FERKIN Nicholas j. HOBBS Benjamin D. FERKIN Adam C.FERKIN daniel A. FERKIN Department of Biological Sciences The University of Memphis Ellington Hall Memphis TN 38152 USA

Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bot- tom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bot- tom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 （4）： 441-448, 2011 ].

关键词： Over-marks Voles Scent marks Olfactory communication

Multi-scale magnetic resonance measurements and validation of Discrete Element Model simulations

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Particuology 2011年第4期9卷 330-341页

作者： Christoph R. Müller daniel j. Holland james R. Third Andrew j. Sederman john S. Dennis Lynn F. Gladden Institute of Energy Technology Department of Mechanical and Process Engineering Department of Chemical Engineering and Biotechnology University of Cambridge

This short review describes the capabilities of magnetic resonance （MR） to image opaque single- and two-phase granular systems, such as rotating cylinders and gas-fluidized beds operated in different fluidization regimes. The unique capability of MR to not only image the solids＇ distribution （voidage） but also the velocity of the particulate phase is clearly shown. It is demonstrated that MR can provide measurements over different length and time scales. With the MR equipment used for the studies summarized here, temporal and spatial scales range from sub-millisecond to hours and from a few hundred micrometres to a few centimetres, respectively. Besides providing crucial data required for an improved understanding of the underlying physics of granular flows, multi-scale MR measurements were also used to validate numerical simulations of granular systems. It is shown that predictions of time-averaged properties, such as voidage and velocity of the particulate phase, made using the Discrete Element Model agree very well with MR measurements.

关键词： Discrete Element Modelling Magnetic resonance imaging MultiscaleGas-fluidized beds Rotating cylinders

A functional type I interferon pathway drives resistance to cornea herpes simplex virus type 1 infection by recruitment of leukocytes

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The journal of Biomedical Research 2011年第2期25卷 111-119页

作者： Christopher D. Conrady Heather jones Min Zheng daniel j.j. Carr Departments of Microbiology Immunology The University of Oklahoma Health Science Center Oklahoma City OK 73104 USA Departments of Ophthalmology The University of Oklahoma Health Science Center Oklahoma City OK 73104 USA

Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 （HSV-1） infection that act to inhibit viral spread. In the present study, we identify HSV-infected and adjacent uninfected corneal epithelial cells as the source of interferon-a. We also report mice deficient in the A1 chain of the type I IFN receptor （CDl18-/） are extremely sensitive to ocular infection with low doses （100 PFU） of HSV-1 as seen by significantly elevated viral titers in the cornea Compared to wild type （WT） controls. The enhanced susceptibil- ity correlated with a loss of CD4＋ and CD8＋ T cell recruitment and aberrant chemokine production in the cornea despite mounting an adaptive immune response in the draining mandibular lymph node of CDll8/ mice. Taken together, these results highlight the importance of IFN production in both the innate immune response as well as eliciting chemokine production required to facilitate adaptive immune cell trafficking.

关键词： herpes simplex virus type 1 type I interferon comea viral infection leukocytes ocular immunology

Estimating Pinus palustris tree diameter and stem volume from tree height,crown area and stand-level parameters

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journal of Forestry Research 2014年第1期25卷 43-52页

作者： C.A.Gonzalez-Benecke Salvador A.Gezan Lisa j.Samuelson Wendell P.Cropper daniel j.Leduc Timothy A.Martin School of Forest Resources and Conservation P.O.Box 110410University of Florida School of Forestry and Wildlife Sciences 3301SFWS BuildingAuburn University USDA Forest Service Southern Research StationAlexandria Forestry Center

Accurate and efficient estimation of forest growth and live biomass is a critical element in assessing potential responses to forest management and environmental change. The objective of this study was to develop models to predict longleaf pine tree diameter at breast height （dbh） and merchantable stem volume （V） using data obtained from field measurements. We used longleaf pine tree data from 3,376 planted trees on 127 permanent plots located in the U.S. Gulf Coastal Plain region to fit equations to predict dbh and V as functions of tree height （H） and crown area （CA）. Prediction of dbh as a function of H improved when CA was added as an additional independent variable. Similarly, predic- tions of V based on H improved when CA was included. Incorporation of additional stand variables such as age, site index, dominant height, and stand density were also evaluated but resulted in only small improvements in model performance. For model testing we used data from planted and naturally-regenerated trees located inside and outside the geographic area used for model fitting. Our results suggest that the models are a robust alternative for dbh and V estimations when H and CA are known on planted stands with potential for naturally-regenerated stands, across a wide range of ages. We discuss the importance of these models for use with metrics derived from remote sensing data.

关键词： Longleaf pine diameter-height relationships crown area individual-tree stem volume growth and yield modeling

Boudouard reaction driven by thermal plasma for efficient CO2 conversion and energy storage

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journal of Energy Chemistry 2020年第6期29卷 128-134,I0006页

作者： Zhikai Li Tao Yang Shaojun Yuan Yongxiang Yin Edwin j.Devid Qiang Huang daniel Auerbach Aart W.Kleyn School of Chemical Engineering Sichuan UniversityChengdu 610065SichuanChina Center of Interface Dynamics for Sustainability Institute of MaterialsChina Academy of Engineering PhysicsChengdu 610200SichuanChina School of Biological and Chemical Engineering Panzhihua UniversityPanzhihua 617000SichuanChina School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

Conversion of CO2 into CO using plasma processing powered by renewable energy is a promising method to convert intermittent sustainable electricity into storable chemical *** extensive research efforts worldwide,there is currently no process that achieves economically viable values for both CO2 conversion fraction and energy recovery efficiency *** we demonstrate that a process that utilizes the Boudouard reaction,CO^2++C→2 CO,driven by a thermal plasma allows both 95%CO2 conversion to CO and energy recovery efficiency of 70%,values far higher than seen so *** comparing the conversion process with and without CO2 excitation by a plasma and by using optical emission spectroscopy we show that the improved performance is due to a novel mode of operation where CO2 is pyrolyzed into an active mixture of CO,O and O2 by an arc discharge which is then introduced into a fixed bed to interact with carbon *** this way,the free oxygen in the mixture combusts with carbon to form CO,and residual plasma excited CO2 is reduced by *** the overall process,the endothermic Boudouard reaction is partially replaced by an exothermic reaction,and the excess electric energy to produce CO2 plasma is reused in the carbon bed.

关键词： Boudouard reaction Thermal plasma CO2 conversion Energy recovery efficiency

Towards a business model for second-life batteries: Barriers,opportunities, uncertainties, and technologies

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journal of Energy Chemistry 2023年第3期78卷 507-525,I0014页

作者： Carlos Antônio Rufino júnior Eleonora Riva Sanseverino Pierluigi Gallo daniel Koch Yash Kotak Hans-Georg Schweiger Hudson Zanin Advanced Energy Storage Division New Energy Innovation CenterUniversity of Campinas(UNICAMP)Campinas 13083-852Brazil Engineering Department University of Palermo(UNIPA)Palermo 90128Italy Consorzio Nazionale Interuniversitario per le Telecomunicazioni(CNIT) Parma 43124Italy Technische Hochschule Ingolstadt Institute for ElectricConnected and Safe Mobility(C-ECOS)Ingolstadt 85049Germany

Electric vehicles(EVs) and the recent pandemic outbreak give cities a new trend to primarily private and shared mobility with low noise and less air *** factors for the widespread of EVs are the electrical charging infrastructure,driving range,and the reduction of the cost of battery *** this reason,there is a massive effort from manufacturers,governments,and the scientific community to reduce battery costs and boost sustainable electrical production and *** reuse is an alternative to reduce batteries’ costs and environmental ***-life batteries can be used in a wide variety of secondary ***-life batteries can be connected with off-grid or on-grid photovoltaic and wind systems,vehicle charging stations,forklifts,and frequency *** present work aims to analyze the main challenges imposed on the reuse of batteries,the leading technologies for their reuse,and the different types of batteries in terms of their feasibility for second-life *** main novelty of this work is the discussion about the barriers,opportunities,uncertainties,and technologies for the second life *** we summarize the present state of the art in reusing lithium-ion batteries discussing technical and economic feasibility,environmental impacts,and *** results show five business models that have been proposed in the literature,three types of markets for trading second-life batteries,and the main opportunities and barriers for each actor in the battery supply chain.

关键词： Business models Batteries Sustainability Electric vehicles Challenges Opportunities Lithium-ion batteries Reuse

Balancing nutrients in a toxic environment: the challenge of eating

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Insect Science 2022年第1期29卷 289-303页

作者： Peng Wang daniel G.Vassão Bettina Raguschke Michael j.Furlong Myron P.Zalucki School of Biological Sciences The University of QueenslandSt LuciaQueenslandAustralia Department of Biochemistry Max Planck Institute for Chemical EcologyJenaGermany

Insect herbivores can regulate their food intake by mixing food sources with different nutrient content, but face the resulting challenge of ingesting various plant secondary metabolites. How insects deal with toxins in a complex nutrient environment is unclear. Here we investigated the influence of a classic plant secondary metabolite, allyl glucosinolate (sinigrin), and its hydrolyzed product allyl isothiocyanate (AITC), on the development of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) when fed on diets with different protein-to-carbohydrate (p : c) ratios. We also examined the effects of these toxins on larval biochemistry, by chemically analyzing the frass produced by insects feeding on the different diets. As expected, AITC had a greater negative effect than sinigrin on H. armigera life-history traits. However, AITC at low concentration appeared to have a positive effect on some traits. Both sinigrin and AITC-induced detoxification activity in the gut, and the reaction was related to diet protein concentration. High-protein diets can provide the required free amino acid, especially cysteine, needed for the detoxification process. The nutrient content of the diet influences how plant secondary metabolites are handled, and the use of artificial diets in experiments investigating the metabolic fate of plant secondary compounds needs to be carefully evaluated.

关键词： diet protein glucosinolate gut metabolism Helicoverpa armigera isothiocyanate

Spring peepers Pseudacris crucifer modify their call structure in response to noise

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Current Zoology 2014年第4期60卷 438-448页

作者： Dalai E. L. HANNA David R. WILSON Gabriel BLOUIN-DEMERS daniel j. MENNILL Department of Biological Sciences McGill University Montr6al Qu6bec. H3A 1B 1 Canada Department of Biological Sciences University of Windsor Windsor Ontario N9B 3P4 Canada Department of Biology University of Ottawal Ottawa Oniario KIN 6N5 Canada Department of Biological Sciences University of Windsor Windsor Ontario N9B 3P4 Canada

Acoustic interference can impede effective communication that is important for survival and reproduction of animals. In response to acoustic interference, some animals can improve signalling efficacy by altering the structure of their signals. In this study, we played artificial noise to 46 male spring peepers Pseudacris crucifer, on their breeding grounds, and tested whether the noise affected the duration, call rate, and peak frequency of their advertisement calls. We used two experimental noise treatments that masked either the high- or low-frequency components of an average advertisement call; this allowed us to evaluate whether frogs adaptively shift the peak frequency of their calls away from both types of interference. Our playback treatments caused spring peepers to produce shorter calls, and the high-frequency noise treatment caused them to lower the frequency of their calls immediately after the noise ceased. Call rate did not change in response to playback. Consistent with previous studies, ambient temperature was inversely related to call duration and positively related to call rate. We conclude that noise affects the structure of spring peeper advertisement calls, and that spring peepers therefore have a mechanism for altering signal structure in response to noise. Future studies should test if other types of noise, such as biotic or anthropogenic noise, have similar effects on call structure, and if the observed changes to call structure enhance or impair communication in noisy environments [Current Zoology 60 （4）： 438-448, 2014].

关键词： Anurans Animal communication Acoustic communication Frequency Song structure