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Integrative Zoology 2014年第3期9卷 280-293页

作者： Sean t.MA Shanna l.RESENDEZ Brandon J.ARAGONA Department of Psychology Program in Neuroscience University of MichiganAnn ArborMIUSA

Prairie voles(Microtus ochrogaster)are a socially monogamous rodent species and their cooperative behaviors require extensive communication between *** use ultrasonic vocalizations(USVs)to communicate and because a prairie vole breeder pair must engage in extensive cooperation for successful reproduction,auditory communication may be critical for this ***,we sought to characterize USVs in adult male and female prairie voles,and to determine how these calls are influenced by social context,salient social stimuli and the psychostimulant drug of abuse amphetamine(AMPH).Here,we characterize prairie vole USVs by showing the range of frequencies of prairie vole USVs,the proportion of various call types,how these call types compare between males and females,and how they are influenced by social stimulation and *** caused a robust increase in the number of USVs in both males and females and there was a dramatic sex difference in the complexity of call structures of AMPH-induced USVs,with males emitting more elaborate ***,we show that novel(***)social cues evoked differential increases in USVs across sex,with males showing a much more robust increase in USV production,both with respect to the frequency and complexity of USV *** to an estrous female in particular caused an extraordinary increase in USVs in male *** data suggest that USVs may be a useful measure of social motivation in this species,including how social behaviors can be impacted by drugs of abuse.

关键词： amphetamine dopamine mate choice pair bonding ultrasonic vocalization

Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry

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Defence technology（防务技术） 2018年第5期14卷 607-611页

作者： t.li Piani J.Weerheijm l.J.Sluys tU Delft Stevinweg 12628 CNDelftThe Netherlands tNO PO Box 452280 AARijswijkThe Netherlands NlDA Faculty of Military Sciences1781 CADen HelderThe Netherlands

In this paper, a new one-dimensional phenomenological model is developed for the assessment of the ballistic performance of Adobe. Adobe is a masonry largely spread in areas of the world involved in military operations. Addressing fundamental ballistic parameters such as residual velocity or penetration depth for this building technology is necessary. the model follows the hypotheses for the ballistic response of concrete targets to high velocity impacts, provided with a dominant contribution of shear friction typical of soils. the hypotheses at the basis of the model are consistent with all experimental evidence collected by authors on Adobe. Adobe brick and mortar belong to the material class of concrete,whereas the overall mechanical parameters are determined by the internal soil mixture, including the percentage of fibre reinforcement. Despite its relative simplicity, the model is capable of well predicting ballistic test results currently available in literature for Adobe, including the data of an experimental campaign recently performed by the authors on real Adobe walls in the field.

关键词： Impact Penetration Depth Residual velocity Adobe Wall Brick Mortar Ballistic

Functional leaf and size traits determine the photosynthetic response of 10 dryland species to warming

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Journal of Plant Ecology 2016年第6期9卷 773-783页

作者： Enrique Valencia Josél.Quero Fernando t.Maestre Departamento de Biología y Geología Física y Química InorgánicaEscuela Superior de Ciencias Experimentales y TecnologíaUniversidad Rey Juan CarlosC/Tulipán s/n28933 MóstolesSpain Departamento de Ingeniería Forestal Escuela Técnica Superior de Ingeniería Agronómica y de MontesUniversidad de Córdoba Campus de Rabanales CrtaN-IV km.396C.P.14071 CórdobaSpain

Aims Relatively few studies so far have assessed how ongoing global warming will affect the photosynthetic performance of dryland plant *** evaluated the effects of warming on the photosynthetic rates of 10 species with contrasting functional attributes,and whether their functional traits modulated photosynthetic responses to *** A common garden experiment was conducted over 2 years with distinct environmental conditions(drier *** year).the experiment was designed as a randomized block design with two treatments:warming(control vs.~2.9℃ temperature increase)and species(Agropyron cristatum,Festuca ovina,lygeum spartum,Medicago sativa,Plantago lanceolata,Psoralea bituminosa,Sanguisorba minor,Hedysarum coronarium,Dorycnium pentaphyllum and Phlomis herba-venti).We linked functional traits measurements with temporal variations in photosynthetic responses to *** Findings In the drier year,warming increased photosynthetic rates at the beginning of the growing season,suggesting a modification in the growing period(earlier spring).In the wetter year,functional traits modulated photosynthetic responses to *** species with shorter leaves(***)had higher photosynthetic rates under warming compared to smaller species with larger leaves(***).Our results highlight the importance of(i)studying photosynthetic responses along different years and(ii)considering functional traits when evaluating photosynthetic responses to climate change,particularly in stressful environments such as drylands.

关键词： photosynthesis climate change Mediterranean functional traits open top chambers

transport of Nitrogen Assimilation in Xylem Vessels of Green tea Plants Fed with NH_4-N and NO_3-N

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Pedosphere 2008年第2期18卷 222-226页

作者： K. OH t. KAtO H. l. XU Center for Environmental Science in Saitama Saitama 347-0115 （Japan） Jinenjou-no-kai NPO Shizuoka 421-0302 （Japan） International Nature Farming Research Center 5632 Hata Nagano 390-1401 （Japan）

An experiment was carried out to study the transport process of nitrogen （N） assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15^N-NO3 and 15^N-NH4 were fed to the root of tea plants （Camellia sinensis l.）. Results showed that the main amino acids were glutamine, theanine, axginine, asparic acid and glutamic acid, which accounted for 49%, 17%, 8%, 7%, and 4%, respectively, of the total amino acids in the xylem sap. After the tea plants were fed with 15^N-NO3 and 15^N-NH4 for 48 h, the amount of total amino acids in xylem sap significantly increased and those fed with 15^N-NH4 had higher increment than those with 15^N-NOa. two hours after 15^N- NO3 and 15^N-NH4 were fed, 15N abundance in glutamine, asparagine, glutamic acid, alanine, and arginine were detected and increased quickly over time. this indicated that it took less than 2 h for NO3-N and NH4-N to be absorbed by tea roots, incorporated into the above amino acids and transported to the xylem sap. Rapid increase in 15^N-NO3 in the xylem sap of tea plants fed with 15^N-NO3 indicated that nitrate could be directly transported to the xylem sap. Glutamine, theanine, and alanine were the main amino acids transported in xylem sap of tea plants fed with both 15^N-NO3 and 15^N-NH4.

关键词： amino acid 15^N nitrogen assimilation tea plant xylem sap

Functional and structural changes in internal pudendal arteries underlie erectile dysfunction induced by androgen deprivation

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Asian Journal of Andrology 2017年第5期19卷 526-532页

作者： Rheure Alves-lopes Karla B Neves Marcondes AB Silva Vania C Olivon Silvia G Ruginsk Jose Antunes-Rodrigues leandra nz Ramalho Rita C tostes Fernando Silva Carneiro Department of Pharmacology Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil Department of Physics and Chemistry Faculty of Pharmaceutical Sciences of Ribeirao Preto University of Sao Paulo Ribeirao Preto SP Brazil Department of Physiological Sciences Biomedical Sciences InstituteFederal University of Alfenas Alfenas MG Brazil Department of Physiology Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil Department of Pathology and legal Medicine Ribeirao Preto Medical School University of Sao Paulo Ribeirao Preto SP Brazil

Androgen deficiency is strongly associated with erectile dysfunction （ED）. Inadequate penile arterial blood flow is one of the major causes of ED. the blood flow to the corpus cavernosum is mainly derived from the internal pudendal arteries （IPAs）; however, no study has evaluated the effects of androgen deprivation on IPA＇s function. We hypothesized that castration impairs IPAs reactivity and structure, contributing to ED. In our study, Wistar male rats, 8-week-old, were castrated and studied 30 days after orchiectomy. Functional and structural properties of rat IPAs were determined using wire and pressure myograph systems, respectively. Protein expression was determined by Western blot and immunohistochemistry. Plasma testosterone levels were determined using the IMMUlItE 1000 Immunoassay System. Castrated rats exhibited impaired erectile function, represented by decreased intracavernosal pressure/mean arterial pressure ratio. IPAs from castrated rats exhibited decreased phenylephrine- and electrical field stimulation （EFS）-induced contraction and decreased acetylcholine- and EFS-induced vasodilatation. IPAs from castrated rats exhibited decreased internal diameter, external diameter, thickness of the arterial wall, and cross-sectional area. Castration decreased nNOS and α-actin expression and increased collagen expression, p38 （thr180/ryr182） phosphorylation, as well as caspase 3 cleavage. In conclusion, androgen deficiency is associated with impairment of IPA reactivity and structure and increased apoptosis signaling markers. Our findings suggest that androgen deficiency-induced vascular dysfunction is an event involving hypotrophic vascular remodeling of IPAs.

关键词： androgen castration internal pudendal artery

Prickly pairs: the proportion of spinescent species does not differ between islands and mainlands

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Journal of Plant Ecology 2019年第6期12卷 941-948页

作者： Floret l.Meredith Marianne l.tindall Frank A.Hemmings Angela t.Moles Evolution and Ecology Research Centre School of BiologicalEarth and Environmental SciencesUNSW AustraliaSydneyNSW 2052Australia John t.Waterhouse Herbarium School of BiologyEarth and Environmental SciencesUNSW AustraliaSydneyNSW 2052Australia

Aims Organisms on islands are thought to escape biotic pressure and lose defensive ***,broadscale,evidence-based tests of this idea are *** this study,we asked:(i)whether the proportion of spinescent plant species differed between islands and mainlands and(ii)whether the proportion of spinescent species increased with increasing island area and with decreasing island distance to *** We compiled species lists for 18 island–mainland pairs around *** classified 1129 plant species as spinescent or nonspinescent using published species *** Findings there was no significant difference between the proportion of spinescent species found on islands and on *** of spinescent species were not significantly related to island area or distance to *** results suggest that spinescence is just as important to island plants as it is to mainland plants,even for plants inhabiting small or distal *** is unexpected,given prevailing thought and previous work on island–mainland *** study demonstrates the importance of testing well-accepted yet untested ideas.

关键词： herbivory island biogeography theory physical defence plant community plant defence prickles thorns

DeepSun:machine-learning-as-a-service for solar flare prediction

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Research in Astronomy and Astrophysics 2021年第7期21卷 51-61页

作者： Yasser Abduallah Jason t.l.Wang Yang Nie Chang liu Haimin Wang Institute for Space Weather Sciences New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA Department of Computer Science New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA Big Bear Solar Observatory New Jersey Institute of Technology40386 North Shore LaneBig Bear CityCA 92314-9672USA Center for Solar-terrestrial Research New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA

Solar flare prediction plays an important role in understanding and forecasting space *** main goal of the Helioseismic and Magnetic Imager(HMI), one of the instruments on NASA's Solar Dynamics Observatory, is to study the origin of solar variability and characterize the Sun's magnetic *** provides continuous full-disk observations of the solar vector magnetic field with high cadence data that lead to reliable predictive capability;yet, solar flare prediction effort utilizing these data is still limited. In this paper, we present a machine-learning-as-a-service(Mlaa S) framework, called Deep Sun,for predicting solar flares on the web based on HMI's data products. Specifically, we construct training data by utilizing the physical parameters provided by the Space-weather HMI Active Region Patch(SHARP)and categorize solar flares into four classes, namely B, C, M and X, according to the X-ray flare catalogs available at the National Centers for Environmental Information(NCEI). thus, the solar flare prediction problem at hand is essentially a multi-class(i.e., four-class) classification problem. the Deep Sun system employs several machine learning algorithms to tackle this multi-class prediction problem and provides an application programming interface(API) for remote programming users. to our knowledge, Deep Sun is the first Mlaa S tool capable of predicting solar flares through the internet.

关键词： Sun:flares Sun:activity methods:data analysis

Is the propensity to emit alarm calls associated with health status?

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Current Zoology 2020年第6期66卷 607-614页

作者： Austin l.Nash Alexandra H.M.Jebb Daniel t.BlUMStEIN Department of Ecology and Evolutionary Biology University of Colorado265 UCBBoulderCO 80309USA School of Biological Sciences University of AberdeenZoology BuildingTillydrone AvenueAberdeenAB242TZUK the Rocky Mountain Biological laboratory Box 519 Crested ButteCO 81224USA Department of Ecology and Evolutionary Biology University of California621 Young Drive SouthLos AngelesCA 90095-1606USA

the production and structure of animal signals may depend on an individual's health status and may provide more than one type of information to *** alarm calls are not typically viewed as health condition dependent,recent studies have suggested that their structure,and possibly their propensity to be emitted,depends on an individual,s health condition and *** asked whether the propensity of yellow-bellied marmots(Marmota flaviventer)to emit calls is influen ced by their immuno logical or parasite status,by quantifying both trap-elicited and n atural calling rates as a function of their neutrophil-to-lymphocyte(Nl)ratio,the presence of a blood borne trypanosome,and the presenee of several intestinal parasites(Eimeria sp.,Entamoeba sp.,and Ascaris sp.).We fitted mixed effects models to determine if the health measures we collected were associated with the probability of calling in a trap and with annual rates of natural alarm *** infected with a blood-borne trypanosome were marginally more likely to call naturally and when trapped,while those infected with the intestinal parasite Ascaris were less likely to call when *** ratio was not directly associated with in-trap calling probability,but males were more likely to call when they had higher Nl ***,health conditions,such as parasite infection and immune system activation,can modulate the production of alarm signals and potentially provide in formation to both predators and prey about the caller's *** experiments are required to confirm if receivers use such information.

关键词： alarm calling animal communication antipredator behavior condition dependenee immune function parasites

Chemical Properties and Biochemical Activity of Colonized and Abandoned litter-Feeding termite(Macrotermes spp.) Mounds in Chromic Cambisol Area on the Borana Plateau, Ethiopia

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Pedosphere 2014年第3期24卷 399-407页

作者： l.MENICHEttI l.lANDI P.NANNIPIERI t.KAttERER H.KIRCHMANN G.RENEllA Department of Soil and Environment Swedish University of Agricultural Sciences Department Agrifood Production and Environmental Sciences University of Florence

termite （Macrotermes spp.） mounds are complex biological habitats originated by the termite activity and possessing peculiar physical, chemical and biochemical properties. In this study we examined the concentration of nutrients and the biochemical activity of abandoned soil and mounds colonized by termites of the genera Macroterrnes located in the Borana District, Ethiopia. to elucidate the magnitude and persistence of the termite-induced effects, we also studied an abandoned mound, previously colonized by termites of the same genera formed on the same soil. Results confirmed that termite-colonized mounds are ＇hot spots＇ of nutrient concentration and microbial activity in tropical soils. this is due to the termite driven litter input and decomposition. the abandoned mounds showed higher microbial biomass and activity and displayed a nutrient redistribution and a greater microbial activity than the adjacent soils. these findings allowed us to hypothesize a model of nutrient cycling in colonized soils and a partition of the relative roles of termites and soil microorganisms in nutrient location and turnover in tropical soils. these results may be also useful for the optimal management of termite-colonized soils.

关键词： enzyme activity microbial activity microbial biomass nutrient cycling nutrient turnover

the hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia

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Bone Research 2016年第2期4卷 85-90页

作者： Qian Zhang Michele Doucet Ryan E tomlinson Xiaobin Han l Darryl Quarles Michael t Collins thomas l Clemens Department of Orthopaedic Surgery Johns Hopkins University Baltimore MD USA Department of Medicine University of Tennessee Health Science Center Memphis TN USA Skeletal Clinical Studies Unit craniofacial and Skeletal Diseases Branch National Institutes of HealthBethesda MD USA Baltimore Veterans Administration Medical Center Baltimore MD USA

tumor-induced osteomalacia （tIO） is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 （FGF23） by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures. Recent studies have implicated the hypoxia-inducible factor-la （HIF-la） in other phosphate wasting disorders caused by elevated FGF23, including X-linked hypophosphatemic rickets and autosomal dominant hypophosphatemia. Here we provide evidence that HIF-la mediates aberrant FGF23 in tIO by transcriptionally activating its promoter. Immunohistochemical studies in phosphaturic mesenchymal tumors resected from patients with documented tIO showed that HIF-la and FGF23 were co-localized in spindle- shaped cells adjacent to blood vessels. Cultured tumor tissue produced high levels of intact FGF23 and demonstrated increased expression of HIF-la protein. transfection of MC3t3-E1 and Saos-2 cells with a HIF-la expression construct induced the activity of a FGF23 reporter construct. Prior treatment of tumor organ cultures with HIF-la inhibitors decreased HIF-la and FGF23 protein accumulation and inhibited HIF-la-induced luciferase reporter activity in transfected cells. Chromatin immunoprecipitation assays confirmed binding to a HIF-la consensus sequence within the proximal FGF23 promoter, which was eliminated by treatment with a HIF-la inhibitor. these results show for the first time that HIF-la is a direct transcriptional activator of FGF23 and suggest that upregulation of HIF-la activity in tIO contributes to the aberrant FGF23 production in these patients.

关键词： the hypoxia-inducible factor-1 activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia HIF