Methodology for the realisation of accelerated structural tests on tractors     

Michele Mattetti  Giovanni Molari  Enrico Sedoni 《Biosystems Engineering》2012,113(3):266-271

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Incorporating habitat suitability,landscape distance,and resistant kernels to estimate conservation units for an imperiled terrestrial snake     

Bauder  Javan M.  Chandler  Houston C.  Elmore  Michele L.  Jenkins  Christopher L. 《Landscape Ecology》2022,37(10):2519-2533

Landscape Ecology - Wildlife distributions are often subdivided into discrete conservation units to aid in implementing management and conservation objectives. Habitat suitability models,...  相似文献   

Three periods of regulatory innovation during vertebrate evolution     

Lowe CB  Kellis M  Siepel A  Raney BJ  Clamp M  Salama SR  Kingsley DM  Lindblad-Toh K  Haussler D 《Science (New York, N.Y.)》2011,333(6045):1019-1024

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Mitochondrial biogenesis in mammals: the role of endogenous nitric oxide     

Nisoli E  Clementi E  Paolucci C  Cozzi V  Tonello C  Sciorati C  Bracale R  Valerio A  Francolini M  Moncada S  Carruba MO 《Science (New York, N.Y.)》2003,299(5608):896-899

Nitric oxide was found to trigger mitochondrial biogenesis in cells as diverse as brown adipocytes and 3T3-L1, U937, and HeLa cells. This effect of nitric oxide was dependent on guanosine 3',5'-monophosphate (cGMP) and was mediated by the induction of peroxisome proliferator-activated receptor gamma coactivator 1alpha, a master regulator of mitochondrial biogenesis. Moreover, the mitochondrial biogenesis induced by exposure to cold was markedly reduced in brown adipose tissue of endothelial nitric oxide synthase null-mutant (eNOS-/-) mice, which had a reduced metabolic rate and accelerated weight gain as compared to wild-type mice. Thus, a nitric oxide-cGMP-dependent pathway controls mitochondrial biogenesis and body energy balance.  相似文献   

Enhanced dendritic cell antigen capture via toll-like receptor-induced actin remodeling     

West MA  Wallin RP  Matthews SP  Svensson HG  Zaru R  Ljunggren HG  Prescott AR  Watts C 《Science (New York, N.Y.)》2004,305(5687):1153-1157

Microbial products are sensed through Toll-like receptors (TLRs) and trigger a program of dendritic cell (DC) maturation that enables DCs to activate T cells. Although an accepted hallmark of this response is eventual down-regulation of DC endocytic capacity, we show that TLR ligands first acutely stimulate antigen macropinocytosis, leading to enhanced presentation on class I and class II major histocompatibility complex molecules. Simultaneously, actin-rich podosomes disappear, which suggests a coordinated redeployment of actin to fuel endocytosis. These reciprocal changes are transient and require p38 and extracellular signal-regulated kinase activation. Thus, the DC actin cytoskeleton can be rapidly mobilized in response to innate immune stimuli to enhance antigen capture and presentation.  相似文献   

Effects of fire and fire intensity on the germination and establishment of Acacia karroo, Acacia nilotica, Acacia luederitzii and Dichrostachys cinerea in the field     

Michele Walters  Jeremy J Midgley  Michael J Somers 《BMC ecology》2004,4(1):1-13

Background

The native annual tobacco, Nicotiana attenuata, is found primarily in large ephemeral populations (typically for less than 3 growing seasons) after fires in sagebrush and pinyon-juniper ecosystems and in small persistent populations (for many growing seasons) in isolated washes typically along roadsides throughout the Great Basin Desert of the SW USA. This distribution pattern is due to its unusual germination behavior. Ephemeral populations are produced by the germination of dormant seeds from long-lived seed banks which are stimulated to germinate by a combination of unidentified positive cues found in wood smoke and the removal of inhibitors leached from the unburned litter of the dominant vegetation. Persistent populations may result where these inhibitors do not exist, as in washes or along disturbed roadsides. To determine if this germination behavior has influenced population structure, we conducted an AFLP (244 individuals), ISSR (175 individuals) and ISSR+ AFLP (175 individuals) analysis on plants originating from seed collected from populations growing in 11 wash and burns over 11 years from the SW USA.

Results

Genetic variance as measured by both ISSR and AFLP markers was low among sites and comparatively higher within populations. Cluster analysis of the Utah samples with samples collected from Arizona, California, and Oregon as out-groups also did not reveal patterns. AMOVA analysis of the combined AFLP and ISSR data sets yielded significantly low genetic differentiation among sites (Φct), moderate among populations within sites (Φsc) and higher genetic differentiation within populations (Φst).

Conclusions

We conclude that the seed dormancy of this post-fire annual and its resulting age structure in conjunction with natural selection processes are responsible for significantly low among sites and comparatively high within-population genetic variation observed in this species.  相似文献   

Congenital heart disease in boxer dogs: results of 6 years of breed screening     

Bussadori C  Pradelli D  Borgarelli M  Chiavegato D  D'Agnolo G  Menegazzo L  Migliorini F  Santilli R  Zani A  Quintavalla C 《Veterinary journal (London, England : 1997)》2009,182(2):187-192

This prospective study was conducted to evaluate the prevalence and severity of ocular lesions in dogs with anemia (packed cell volume  20%) and/or thrombocytopenia (platelet count < 150,000/μL). Dogs were divided into four groups: (1) anemic (n = 17); (2) thrombocytopenic (n = 36); (3) anemic and thrombocytopenic (n = 24); and (4) healthy controls (n = 26). The prevalence of ophthalmic lesions in these four groups was 12%, 42%, 42% and 0%, respectively. Anemia was not associated with the presence of ocular lesions (P = 0.41) or their severity. Thrombocytopenia was significantly associated with the presence of ocular lesions (P = 0.0016) and with their severity (P = 0.017). We conclude that thrombocytopenia, but not anemia, is associated with ocular lesions in dogs.  相似文献   

Review of climate change impacts on marine aquaculture in the UK and Ireland     

Ruth Callaway  Andrew P. Shinn  Suzanne E. Grenfell  James E. Bron  Gavin Burnell  Elizabeth J. Cook  Margaret Crumlish  Sarah Culloty  Keith Davidson  Robert P. Ellis  Kevin J. Flynn  Clive Fox  Darren M. Green  Graeme C. Hays  Adam D. Hughes  Erin Johnston  Christopher D. Lowe  Ingrid Lupatsch  Shelagh Malham  Anouska F. Mendzil  Thom Nickell  Tom Pickerell  Andrew F. Rowley  Michele S. Stanley  Douglas R. Tocher  James F. Turnbull  Gemma Webb  Emma Wootton  Robin J. Shields 《水产资源保护:海洋与淡水生态系统》2012,22(3):389-421