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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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Molecular Characterization of the Calvin Cycle Enzyme Phosphoribulokinase in the Stramenopile Alga Vaucheria litorea and the Plastid Hosting Mollusc Elysia chlorotica

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Molecular Plant 2009年第6期2卷 1384-1396页

作者： mary E. Rumpho Sirisha Pochareddy jared M. Worful Elizabeth j. Summer Debashish Bhattacharya Karen N. Pelletreau mary S. Tyler jungho Lee james R. Manhart Kara M. Soule Department of Biochemistry Microbiology and Molecular Biology 5735 Hitchner Halt University of Maine Orono ME 04469 USA Department of Biology Texas A&M University College Station TX 77843 USA Department of Ecology Evolution and Natural Resources Institute of Marine and Coastal Sciences Rutgers University New Brunswick NJ 08901 USA School of Biology and Ecology University of Maine Orono ME 04469 USA Green Plant Institute #2-202 Bio Valley Seoul National University 103-2 Seodun Gwonseon Suwon Gyeonggi 441-853 Korea Department of Biochemistry and Biophysics Texas A&M University College Station TX 77843 USA

Phosphoribulokinase （PRK）, a nuclear-encoded plastid-localized enzyme unique to the photosynthetic carbon reduction （Calvin） cycle, was cloned and characterized from the stramenopile alga Vaucheria litorea. This alga is the source of plastids for the mollusc （sea slug） Elysia chlorotica which enable the animal to survive for months solely by photoautotrophic CO2 fixation. The 1633-bp V. litorea prk gene was cloned and the coding region, found to be interrupted by four introns, encodes a 405-amino acid protein. This protein contains the typical bipartite target sequence expected of nuclearencoded proteins that are directed to complex （i.e. four membrane-bound） algal plastids. De novo synthesis of PRK and enzyme activity were detected in E. chlorotica in spite of having been starved of V. litorea for several months. Unlike the algal enzyme, PRK in the sea slug did not exhibit redox regulation. Two copies of partial PRK-encoding genes were isolated from both sea slug and aposymbiotic sea slug egg DNA using PCR. Each copy contains the nucleotide region spanning exon 1 and part of exon 2 of V litorea prk, including the bipartite targeting peptide. However, the larger prk fragment also includes intron 1. The exon and intron sequences of prk in E. chlorotica and V/itorea are nearly identical. These data suggest that PRK is differentially regulated in V. litorea and E. chlorotica and at least a portion of the V. litorea nuclear PRK gene is present in sea slugs that have been starved for several months.

关键词： Alga Calvin cycle Elysia chlorotica kleptoplast mollusc phosphoribulokinase photosynthesis plastid redox regulation stramenopile symbiosis Vaucheria litorea.

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Harry Potter and the sorcerer's stone

Harry Potter and the sorcerer's stone

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作者： by j.K. Rowling illustrations by mary GrandPr鈋.

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Frankenstein

Frankenstein

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作者： mary Shelley edited by j. Paul Hunter.

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Growth,Structural and Microhardness Studies on New Semiorganic Single Crystals of Calcium Para Nitrophenolate Dihydrate

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journal of Materials Science & Technology 2007年第6期23卷 855-859页

作者： C.Vesta R.Uthrakumar C.justin Raj A.jonie Varjula j.mary Linet S.jerome Das Department of Physics Loyola CollegeChennai-34India

Good quality crystals of calcium p-nitrophenolate （NPCa） were grown from saturated solution by slow evaporation method. The crystal structure analysis and the molecular arrangement of these crystals were determined using X-ray diffraction （XRD）. From Single crystal XRD studies, NPCa is found to be crystallized in the mon- oclinic system with a space group P21/n. The functional groups of the material were confirmed qualitatively by F-FIR （Fourier transform infrared spectroscopy） spectral analysis. Optical absorption studies reveal the absorption region and microhardness studies were carried out to confirm the mechanical behaviour of the crystals.

关键词： Characterization Crystal growth Structural analysis FTIR spectral analysis Microhardness UV-Vis analysis

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Harry Potter and the deathly hallows

Harry Potter and the deathly hallows

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作者： by j.K. Rowling illustrations by mary GrandPr鈋.

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Exercise-dependent regulation of glial cell line-derived neurotrophic factor （GDNF） expression in skeletal muscle and its importance for the neuromuscular system

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Frontiers in Biology 2013年第1期8卷 101-108页

作者： john-mary VIANNEY Monica j. MCCULLOUGH Amy M. GYORKOS, john M. SPITSBERGEN Department of Biological Scienees Western Michigan University Kalamazoo MI 49098-5410 USA

The focus of this review is to highlight the importance of glial cell line-derived neurotrophic factor （GDNF） for the motor nervous system. GDNF is the most potent survival factor for motor neurons, where it enhances maintenance and survival of both developing and mature motor neurons in vivo and in vitro. GDNF aids in neuromuscular junction formation, maintenance, and plasticity, where skeletal muscle-derived GDNF may be responsible for this phenomenon. Increased levels of physical activity can increase GDNF protein levels in skeletal muscle, where alterations in acetylcholine and acetylcholine receptor activation may be involved in regulation of these changes observed. With inactivity and disuse, GDNF expression shows different patterns of regulation in the central and peripheral nervous systems. Due to its potent effects for motor neurons, GDNF is being extensively studied in neuromuscular diseases.

关键词： glial cell line-derived neurotrophic factor neuromuscular junction motor neurons skeletal muscle

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STRESS ANALYSIS OF ALUMINA COATINGS ON SILICON CARBIDE BASED REFRACTORIES DURING THERMAL CYCLING

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journal of Wuhan University of Technology(Materials Science) 1999年第3期14卷 9-15页

作者：潘牧 Wuhan University of Technology China State Key Lab. Adv. Technol. Mat. S. Wuhan University of Technology Wuhan 430070 China Monash University Australia

It is possible to enhance the high tempera- ture oxidationresistance and thus prolong the life time of non-oxide refractoriesby the application of oxide coating. In this work, silicon nitridebonded silicon carbide refracto- Ries were coated with alumina usingthe plasma spraying Technique. X-ray diffraction showed γ-Al_2O_3 tobe the Dominent phase in the as-sprayed alumina coatings.

关键词： alumina cosatings refractory Plasma spraying

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Measuring Surface Roughness through the Use of Digital Photography and Image Processing

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International journal of Geosciences 2014年第5期5卷 540-554页

作者： mary j. Thornbush School of Geography Earth and Environmental Sciences University of Birmingham Birmingham UK

This paper aims to provide a quantitative method that employs image processing in the assessment of surface roughness based on digital photograph field surveys, as in previous studies employing the outdoor integrated digital photography and image processing (O-IDIP) method. Digital photographs were taken on two different days under contrasting outdoor lighting conditions (overcast versus clear sky). Images were captured mounted on a tripod close up to the surface of a 380-year-old wall located at the University of Oxford Botanic Garden in the City of Oxford, UK. Sampling points were established at regular intervals along the border wall and encompassed sections facing west, north, and east, respectively along the survey. Two photographs were taken with a digital camera at each sampling point, one containing a color chart used to calibrate outdoor lighting conditions across images, which was excluded from the other photographic pair. Histogram-based quantification was performed based on images converted to Lab Color mode. The 10-step calibration procedure presented in this paper required more adjustments of contrast. However, more adjustments were not required under a clear sky. Std Dev L measurements were used to establish categories in a simple 3-point roughness index, namely the surface roughness index (SRI). The results denote that pitting did not affect surface roughness measurements. The study shows that it is possible to use Std Dev L measurements to quantify surface roughness on a comparative basis.

关键词： Nondestructive Assessment Quantitative Photography O-IDIP Rock Weathering Historical Buildings and Structures Urban Environments

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EASE-DGGS:a hybrid discrete global grid system for Earth sciences

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Big Earth Data 2022年第3期6卷 340-357页

作者： jeffery A.Thompson mary j.Brodzik Kevin A.T.Silverstein Mason A.Hurley Nathan L.Carlson Minnesota Supercomputing Institute University of MinnesotaMinneapolisMNUSA GEMS Informatics Initiative University of MinnesotaMinneapolisMNUSA National Snow and Ice Data Center Cooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderCOUSA

Although we live in an era of unprecedented quantities and access to data,deriving actionable information from raw data is a hard *** observation systems(EOS)have experienced rapid growth and uptake in recent decades,and the rate at which we obtain remotely sensed images is *** significant effort and attention has been devoted to designing systems that deliver analytics ready imagery faster,less attention has been devoted to developing analytical frameworks that enable EOS to be seamlessly integrated with other data for quantitative *** global grid systems(DGGS)have been proposed as one potential solution that addresses the challenge of geospatial data integration and ***,we propose the systematic extension of EASE-Grid in order to provide DGGS-like characteristics for EOS data *** describe the extensions as well as present implementation as an application programming interface(API),which forms part of the University of Minnesota’s GEMS(Genetic x Environment x Management x Socioeconomic)Informatics Center’s API portfolio.

关键词： Discrete global grid systems DGGS EASE Grid coordinate reference systems

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