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Rangeland hillslope lengths:A case study at the Walnut Gulch Experimental Watershed,southeastern Arizona

International Soil and Water conservation Research 2022年第4期10卷 597-609页

作者： Li Li Mark A.Nearing Philip Heilman mary H.Nichols D.P.Guertin c.J.Williams School of Natural Resources and the Environment University of ArizonaTucsonAZ85705USA USDA-Agricultural Research Service Southwest Watershed Research CenterTucsonAZ85719USA

Rangeland hillslopes provide much of the sediment supplied to channel systems and their lengths exert a fundamental constraint on hillslope diffusive ***,information regarding lengths of rangeland hillslopes,and how best to estimate them,is *** this study,three groups of watersheds(10 in total)were selected from the Walnut Gulch Experimental Watershed according to their geology,soil and vegetation *** 1 watersheds were at lower elevations dominated by shrubs,Group 3 were at high elevations dominated by grass,and Group 2 were mixed shrub and *** hillslope lengths were calculated from 1 m-resolution DEMs using three methods:a flow routing algorithm,slope-area relationships,and inverted relationship with drainage *** that characterize the current watersheds,including Hack's exponent and coefficient,watershed shape coefficient,channel concavity and steepness,and surface roughness,were quantified and related to hillslope *** shows:(1)estimated hillslope lengths were different for the three methods and between the three groups of watersheds;(2)hillslope lengths that measured from the flow routing algorithm for the ten selected watersheds primarily ranged from 30 to 100 m,with a median value of 63.0 m,which was 20%e50%greater than those derived from slope-area plots or drainage densities;(3)hillslope lengths estimated from the flow routing method were greater in Group 3 watersheds than in Group 2 and then in Group 1 *** attributed these differences in hillslope lengths to the historic epeirogenic pulses,watershed and drainage network morphology,and differences in vegetation characteristics;(4)measured hillslope lengths from the flow routing algorithm were best correlated with hillslope relief,then surface roughness,channel steepness and *** results would benefit the applications of hydrological and erosion models in rangelands.

关键词： Rangeland hillslope Slope length Drainage density Slope-area relationship Hillslope hydrology

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Morphology and viability of adult Fasciola gigantica(giant liver flukes) from Philippine carabaos(Bubalus bubalis) upon in vitro exposure to lead

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Asian Pacific Journal of Tropical Biomedicine 2015年第6期5卷 491-493页

作者： Aimee caye G. chang mary Jane c. Flores Biology Department College of Science De La Salle University

Objective: To evaluate the effects of lead in the morphology and viability of Fasciola gigantica(F. gigantica)(giant liver fluke) isolated from infected livers of carabaos in vitro using the following concentrations of lead: 0, 100, 150 and 200 mg/L. Methods: In vitro viability and motility assay was conducted to evaluate the ef ects of lead using 1% methylene blue as the vital dye for assessment of the l ukes' viability. Results: Results indicate that F. gigantica can tolerate lead exposure as high as 200 mg/L with visible morphological variations. Upon exposure to lead, liver l ukes tend to curl and excrete black precipitates as a sign of physiological stress response. Furthermore, the lethal concentration(Lc50) of lead against F. gigantica in vitro was 160 mg/L. conclusions: In conclusion, tolerance of liver flukes to high levels of lead suggests its potential as a possible biomarker of environmental pollution.

关键词： Fasciola gigantica Giant liver fluke carabaos Heavy metal Lead Lc50 Philippines

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Androgen and bone mass in men

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Asian Journal of Andrology 2003年第2期5卷 148-154页

作者： Annie W.c.Kung Department of Medicine University of Hong Kong Queen Mary Hospital Hong Kong China

Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function,... 详细信息

ct>Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function, activity and lifespan through complex mechanisms. Also androgens increase periosteal bone apposition, resulting in larger bone size and thicker cortical bone in men. There is convincing evidence to show that aromatization to estrogens was an important pathway for mediating the action of testosterone on bone physiology. Estrogen is probably the dominant sex steroid regulating bone resorption in men, but both testosterone and estrogen are important in maintaining bone formation.

关键词： bone of as et Androgen and bone mass in men in

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Antifouling Activities of Marine Bacteria Associated with Sponge (Sigmadocia sp.)

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Journal of Ocean University of china 2012年第3期11卷 354-360页

作者： S. Satheesh A. R. Soniamby c. V. Sunjaiy Shankar S. mary Josephine Punitha centre for Marine Science and Technology Manonmaniam Sundaranar University Pannaiyoor Rajakamangalam-629502 Kanyakumari District Tamil Nadu India Department of Marine Biology Faculty of Marine Sciences King Abdulaziz UniversityJeddah Saudi Arabia Department of Biotechnology Udhaya College of Arts and Science Velamodi Kanyakumari-dist Tamil Nadu India

The present study aimed at assessing the antifouling activity of bacteria associated with marine sponges. A total of eight bacterial strains were isolated from the surface of sponge Sigmadocia sp., of them, SS02, SS05 and SS06 showed inhibitory activity against biofilm-forming bacteria. The extracts of these 3 strains considerably affected the extracellular polymeric substance producing ability and adhesion of biofilm-forming bacterial strains. In addition to disc diffusion assay, microalgal settlement assay was carried out with the extracts mixed with polyurethane wood polish and coated onto stainless steel coupons. The extract of strain SS05 showed strong microalgal settlement inhibitory activity. Strain SS05 was identified as Bacillus cereus based on its 16S rRNA gene. Metabolites of the bacterial strains associated with marine invertebrates promise to be developed into environment-friendly antifouling agents.

关键词： biofouling biofilm bioactive compound sponge bacterium marine natural product

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Are eavesdroppers multimodal？ Sensory exploitation of floral signals by a non-native cockroach Blatta orientalis

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current Zoology 2011年第2期57卷 162-174页

作者： Rodrigo c. VERGARA Alejandra TORRES-ARANEDA Diego A. VILLAGRA Robert A. RAGUSO mary T. K. ARROYO cristian A. VILLAGRA Instituto de Ecologfa y Biodiversidad IEB Universidad de Chile Santiago Chile centro de Recursos Naturales y Medio Ambiente Departamento de Qufmica Facultad de Ciencias Universidad de Tarapaca Arica Chile Department of Neurobiology and Behavior Cornell University Ithaca NY 14853 USA Instituto de Entomologfa Universidad Metropolitana de Ciencias de la Educacion Casilla 147 SantiagoChile

The study of multi-modal communication has only recently been extended to innate and learned interactions between flowers and their animal visitors, and usually only to pollinators. Here we studied the relevance of floral scent and visual display of a night blooming, putatively hawkmoth-pollinated plant Oenothera acaulis （Onagraceae） in the attraction of non-native cockroaches Blatta orientalis （Blattodea： Blattidae）, which function as facultative floral larcenists in coastal habitats of central chile. We experimentally decoupled visual （corolla） and olfactory （fragrance） stimuli by presenting paper corollas and green mesh bags, with or without a freshly-picked natural flower inside. We then contrasted the behavioral responses of roaches in these treatments with those to the natural combination of traits in actual flowers and their respective control treatments, measuring the roaches＇ frequency of first visits, mean and total residence time spent in each treatment. The roaches primarily used olfactory cues when approaching O. acaulis flowers at two biologically relevant spatial scales. In addition, the presence of conspecific roaches had a strong influence on recruitment to the experimental arena, increasing the statistical differences among treatments. Our results suggest a primacy of floral fragrance over visual stimuli in the foraging responses of B. orientalis. Olfactory cues were necessary and sufficient to attract the roaches, and the visual cues presented in our manipulations only marginally increased their attraction within a 20 cm diameter of the stimulus. The full spectrum of floral visitation behavior was not elicited by the artificial flowers, suggesting the need for additional tactile or contact chemosensory stimuli not provided by paper. Although the nitrogenous scent compounds that we found in O. acaulis flowers are almost exclusively found in hawkmoth-pollinated flowers, the attractiveness of these compounds to a non-native, facultative flower-visiti

关键词： Flower fragrance corolla visual display Larcenists Night-blooming plants

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Osteoblast-restricted Disruption of the Growth Hormone Receptor in Mice Results in Sexually Dimorphic Skeletal Phenotypes

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Bone Research 2013年第1期1卷 85-97页

作者： Vandana Singhal Brian c.Goh mary L.Bouxsein Marie-claude Faugere Douglas J.DiGirolamo Department of Orthopaedic Surgery Johns Hopkins University School of MedicineBaltimoreMDUSA center for Advanced Orthopedic Studies Beth Israel Deaconess Medical Center and Harvard Medical SchoolBostonMAUSA Albert B.chandler Medical center University of KentuckyLexingtonKYUSA

Growth hormone （GH） exerts profound anabolic actions during postnatal skeletal development, in part, through stimulating the production of insulin-like growth factor-1 （IGF-1） in liver and skeletal tissues. To examine the requirement for the GH receptor （GHR） in osteoblast function in bone, we used cre-LoxP methods to disrupt the GHR from osteoblasts, both in vitro and in vivo. Disruption of GHR from primary calvarial osteoblasts in vitro abolished GH-induced signaling, as assessed by JAK2/STAT5 phosphorylation, and abrogated GH-induced proliferative and anti-apoptotic actions. Osteoblasts lacking GHR exhibited reduced IGF-l-induced Erk and Akt phosphorylation and attenuated IGF-1-induced proliferation and anti-apoptotic action. In addition, differentiation was modestly impaired in osteoblasts lacking GHR, as demonstrated by reduced alkaline phosphatase staining and calcium deposition. In order to determine the requirement for the GHR in bone in vivo, we generated mice lacking the GHR specifically in osteoblasts （△GHR）, which were born at the expected Mendelian frequency, had a normal life span and were of normal size. Three week-old, female AGHR mice had significantly reduced osteoblast numbers, consistent with the in vitro data. By six weeks of age however, female AGHR mice demonstrated a marked increase in osteoblasts, although mineralization was impaired; a phenotype similar to that observed previously in mice lacking IGF-1R specifically in osteoblasts. The most striking phenotype occurred in male mice however, where disruption of the GHR from osteoblasts resulted in a ＂feminization＂ of bone geometry in 16 week-old mice, as observed by facT. These results demonstrate that the GHR is required for normal postnatal bone development in both sexes. GH appears to serve a primary function in modulating local IGF-1 action. However, the changes in bone geometry observed in male AGHR mice suggest that, in addition to facilitating IGF-1 action, GH may function to a greater

关键词： growth hormone osteoblasts knockout mice bone sexual dimorphism

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cOVID-19 vaccination produces exercise-responsive SARS-coV-2 specific T-cells regardless of infection history

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Journal of Sport and Health Science 2024年第1期13卷 99-107页

作者： Kyle A.Smith Tiffany M.Zúñiga Forrest L.Baker Helena Batatinha charles R.Pedlar Shane c.Burgess Michael P.Gustafson Emmanuel Katsanis Richard J.Simpson School of Nutritional Sciences and Wellness The University of ArizonaTucsonAZ 85721USA Department of Pediatrics The University of ArizonaTucsonAZ 85724USA Faculty of Sport Allied Health and Performance ScienceSt.Mary's UniversityTwickenham TW14SXUK Institute of Sport Exercise and Health University College LondonLondon WC1E 7HUUK Department of Animal and comparative Biomedical Sciences The University of ArizonaTucsonAZ 85721USA The University of Arizona cancer center The University of ArizonaTucsonAZ 85719USA Laboratory Medicine and Pathology Mayo Clinic ArizonaPhoenixAZ 85054USA Department of Immunobiology The University of ArizonaTucsonAZ 85724USA Department of Medicine The University of ArizonaTucsonAZ 85724USA Department of Pathology The University of ArizonaTucsonAZ 85724USA

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SARS-coV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(cOVID-19).We sought to determine if cOVID-19 vaccination would elicit exercise-responsive SARS-coV-2 T-cells and transiently alter nAb ***:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a cOVID-19 *** major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SARS-coV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TcR)-βsequencing,and SARS-coV-2 nAb ***:cOVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded ***,non-infected participants had a significantly reduced mobilization of cD4+and cD8+naive T-cells,as well as cD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SARS-coV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SARS-coV-2 specific T-cells to blood in an intensity-dependent *** groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid *** increased significantly during exercise only in the hybrid immunity ***:These data indicate that acute exercise mobilizes SARS-coV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

关键词： Anti-viral cOVID-19 Exercise immunology SARS-coV-2 T-cells Vaccine

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Prevalence of vitreous floaters in a community sample of smartphone users

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International Journal of Ophthalmology(English edition) 2013年第3期6卷 402-405页

作者： Blake F. Webb Jadon R. Webb mary c. Schroeder carol S. North Texas Tech University Health Sciences center Texas Tech University child Study center Yale University Department of Pharmacy Practice and Science University of Iowa Department of Psychiatry UT Southwestern

AIM: To estimate the prevalence and risk factors for vitreous floaters in the general population. ·METHODS: An electronic survey was administered through a smartphone app asking various demographic and health questions, including whether users experience floaters in their field of vision. Multivariate logistic regression analysis was used to determine risk factors. ·RESULTS: A total of 603 individuals completed the survey, with 76% reporting that they see floaters, and 33% reporting that floaters caused noticeable impairment in vision. Myopes were 3.5 times more likely (P =0.0004), and hyperopes 4.4 times more likely (P =0.0069) to report moderate to severe floaters compared to those with normal vision. Floater prevalence was not significantly affected by respondent age, race, gender, and eye color. ·cONcLUSION: Vitreous floaters were found to be a very common phenomenon in this non -clinical general population sample, and more likely to be impairing in myopes and hyperopes.

关键词： vitreous floaters myopia survey floaters age

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Biological conversion of low-grade coal discard to a humic substance-enriched soil-like material

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International Journal of coal Science & Technology 2017年第2期4卷 183-190页

作者： Lerato mary Sekhohola Ashton Keith cowan Institute for Environmental Biotechnology RhodesUniversity (EBRU) P.O. Box 94 Graharnstown 6140 SouthAfrica

A mutualistic relationship between grasses, coal-degrading fungi, and arbuscular mycorrhizal fungi was pro- posed to account for the phyto-biodegradation of coal discard. In this study pot trial experiments were carried out to confirm transformation of the carbonaceous substrate, in the presence of a suite of coal degrading fungi and arbuscular mycorrhizal fungi, into a humic-enriched soil-like material in the cynodon dactylon/coal rhizosphere. The results show that after 47 weeks of c. dactylon growth on coal discard the concentration of humics increased from （62.9 -4- 1.5） to （112.1 ＋ 5.4） mg/kg. Substrate humic acid-like substance concentration positively correlated （r2 = 0.95） with accumu- lation of above ground c. dactylon biomass. FTIR spectroscopy of the extracted humic-like substances confirmed both product identity and increased oxidation of the coal discard substrate. Substrate ash content and electrical conductivity declined coincident with an increase in humic acid-like substance concentration, which together reduced the intensity of acidity in the c. dactylon/coal discard rhizosphere. These observations support the proposal that biological oxidative degradation of coal discard leads to increased humic-like substance concentration and formation of a soil-like material. Results have profound implications for use of coal discard as an organic substrate to replace topsoil in phyto-bioreme- diation strategies for sustainable large-scale rehabilitation of coal discard dumps.

关键词： Biodegradation cynodon dactylon Humic acid-like substances Neosartorya fischeri coal discard

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The role of cystatin A in breast cancer and its functional link with ERa

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Journal of Genetics and Genomics 2017年第12期44卷 593-597页

作者： Dixcy Jaba Sheeba John mary Mohan c.Manjegowda Ajay Kumar Sarbajeet Dutta Anil M.Limaye Department of Biosciences and Bioengineering Indian Institute of Technology GuwahatiGuwahati 781039India

Aberrant expression of lysosomal cysteine proteinases（cathepsins）leads to abnormal proteolytic processing of extracellular matrix *** in turn promotes invasion,migration and metastasis of tumor cells（Nomura and Katunuma,2005）.cystatins are natural inhibitors of ***,dysregulated expression of cystatins and the consequent alteration in the cathepsin：cystatin ratio are likely to play an important role in malignant progression of tumors.

关键词： breast cancer link with ERa

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