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A Critical Review of the Evidence for M32 being a Compact Dwarf Satellite of M31 rather than a More Distant Normal Galaxy

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Chinese j.urnal of Astronomy and Astrophysics 2008年第4期8卷 369-384页

作者： C. Ke-shih Young Malcolm j. Currie robert j. Dickens A-Li Luo Tong-j.e Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Department of Physics University of Hong Kong Hong Kong China School of Physics University of New South Wales Sydney 2052 Australia Rutherford Appleton Laboratory Chilton Didcot Oxfordshire OX 11 0QX Great Britain Department of Astronomy Beijing Normal University Beijing 100875 China

Since Baade＇s photographic study of M32 in the mid 1940s, it has been accepted as an established fact that M32 is a compact dwarf satellite of M31. The purpose of this paper is to report on the findings of our investigation into the nature of the existing evidence. We find that the case for M32 being a satellite of M31 rests upon Hubble Space Telescope （HST） based stellar population studies which have resolved red-giant branch （RGB） and red clump stars in M32 as well as other nearby galaxies. Taken in isolation, this recent evidence could be considered to be conclusive in favour of the existing view. However, the conventional scenario does not explain M32＇s anomalously high central velocity dispersion for a dwarf galaxy （several times that of either NGC 147, NGC 185 or NGC 205） or existing planetary nebula observations （which suggest that M32 is more than twice as distant as M31） and also requires an elaborate physical explanation for M32＇s inferred compactness. Conversely, we find that the case for M32 being a normal galaxy, of the order of three times as distant as M31, is supported by：（1） a central velocity dispersion typical of intermediate galaxies, （2） the published planetary nebula observations, and （3） known scaling relationships for normal early-type galaxies. However, this novel scenario cannot account for the high apparent luminosities of the RGB stars resolved in the M32 direction by HST observations. We are therefore left with two apparently irreconcilable scenarios, only one of which can be correct, but both of which suffer from potentially fatal evidence to the *** suggests that current understanding of some relevant fields is still very far from adequate.

关键词： galaxies:individual M32 - galaxies distances and redshifts - galaxies dwarf- galaxies elliptical and lenticular, cD - galaxies fundamental parameters

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Acetylsalicylic acid supplementation improves protein utilization efficiency while vitamin E supplementation reduces markers of the inflammatory response in weaned pigs challenged with enterotoxigenic ***

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j.urnal of Animal Science and Biotechnology 2017年第1期8卷 143-153页

作者： j.e Cheol Kim Bruce P. Mullan j.hn L. Black robert j. E. Hewitt robert j. van Barneveld j.hn R. Pluske School of Veterinary and Life Sciences Murdoch University Murdoch WA 6150 Australia Department of Agriculture and Food Pork Innovation South Perth WA 6151 Australia j.hn L Black Consulting Warrimoo NSW 2774 Australia SunPork Farms Solutions Loganholme QLD 4129 Australia Barneveld Nutrition Pry Ltd Loganholme QLD 4129 Australia

Background： This experiment was conducted to test the hypothesis that vitamin E（Vit E） and acetylsalicylic acid（ASA）, a cyclooxygenase-2（COX-2） inhibitor, will additively reduce the production of the immunosuppressive molecule prostaglandin E_2（PGE_2） and hence reduce inflammatory responses in weaner pigs experimentally infected with an enterotoxigenic strain of E. ***： The experiment was conducted in a research facility with 192 individually-housed male weaner pigs（Landrace × Large White） weighing 6.6 ± 0.04 kg（mean ± SEM）. The pigs were experimentally infected with an enterotoxigenic strain of E. coli and were allocated to a 2 × 3 factorial design with the respective factors being without and with 125 ppm ASA and three levels of Vit E supplementation（50, 100 or 200 IU/kg diet, dl-α-tocopheryl acetate）.Results： Acetylsalicylic acid supplementation improved average daily gain（P 〈 0.05） and tended to improve feed：gain ratio（P 〈 0.10） during the first 14 d after weaning. Acetylsalicylic acid supplementation also improved（P 〈 0.001） amino acid utilization efficiency（as assessed by plasma urea level） and tended to decrease（P 〈 0.10） PGE2 production in the liver without affecting smal intestinal histology and tight j.nction protein mR NA expression in the j.j.nal epithelium. Vitamin E supplementation greater than 100 IU/kg diet sustained both the plasma Vit E concentration（P 〈 0.001） and plasma haptoglobin content（P 〈 0.001） after weaning. However, there was no additive effects of the combined supplementation of ASA and Vit E on performance, intestinal barrier function and inflammatory responses of weaned ***： Although ASA and vitamin E improved amino acid utilization efficiency and reduced acute inflammatory responses, ASA and vitamin E did not additively reduce production of PGE2 and inflammatory responses in weaner pigs experimental y infected with an enterotoxigenic strain of E. coli.

关键词： Acetylsalicylic acid E.coli infection PGE_2 Vitamin E Weaner pigs

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The Orosirian(1800–2050 Ma)plate tectonic episode:Key for reconstructing the Proterozoic tectonic record

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Geoscience Frontiers 2023年第3期14卷 1-9页

作者： robert j.Stern Geosciences Dept. U Texas at DallasRichardsonTX 75083-0688United States

Eight lines of evidence indicate that the Orosirian Period in mid-Paleoproterozoic time was characterized by plate tectonics:ophiolites,low T/P metamorphism including eclogites,passive margin formation,tall mountains,paleomagnetic constraints,ore deposits,abundant S-type granites,and seismic images of paleo-subduction *** plate tectonic episode occurred about 1 billion years earlier than the present plate tectonic episode began in Neoproterozoic *** two plate tectonic episodes bracket the‘Boring Billion’,which may have been a protracted single lid tectonic episode that began when the supercontinent Nuna or Columbia *** of multiple lines of evidence for Orosirian plate tectonics demonstrates that Earth’s tectonic style can be reconstructed with some confidence back to at least Early Paleoproterozoic time,and thus the absence of compelling evidence for Mesoproterozoic plate tectonics is not obvious due to poor preservation.A tectono-magmatic lull2.3 Ga suggests an earlier episode of single lid *** for two episodes of plate tectonics and two episodes of single lid tectonics indicates that Earth switched between single lid and plate tectonics multiple times during the last 2.4 Ga.

关键词： Plate tectonics Single lid tectonics Urey ratio Paleoproterozoic

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Identification and characterization of GIP1, an Arabidopsis thaliana protein that enhances the DNA binding affinity and reduces the oligomeric state of G-box binding factors

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Cell Research 2005年第8期15卷 567-575页

作者： Paul C. SEHNKE,Beth j. LAUGHNER,Carla R. LYERLY LINEBARGER,William B. GURLEY,robert j. FERL Program in Plant Cellular and Molecular Biology Department of Horticultural Sciences University of Florida Gainesville FL USA 32611 Program in Plant Cellular and Molecular Biology Department of Horticultural Sciences University of Florida Gainesville FL USA 32611 Program in Plant Cellular and Molecular Biology Department of Horticultural Sciences University of Florida Gainesville FL USA 32611 Department of Microbiology and Cell Science University of Florida Gainesville FL USA 32611 Program in Plant Cellular and Molecular Biology Department of Horticultural Sciences University of Florida Gainesville FL USA 32611

Environmental control of the alcohol dehydrogenase (Adh) and other stress response genes in plants is in part brought about by transcriptional regulation involving the G-box cis-acting DNA element and bZIP G-box Binding Factors (GBFs). The mechanisms of GBF regulation and requirements for additional factors in this control process are not well understood. In an effort to identify potential GBF binding and control partners, maize GBF1 was used as bait in a yeast two-hybrid screen of an A. thaliana cDNA library. GBF Interacting Protein 1 (GIP1) arose from the screen as a 496 amino acid protein with a predicted molecular weight of 53,748 kDa that strongly interacts with GBFs. Northern analysis of A. thaliana tissue suggests a 1.8-1.9 kb GIP1 transcript, predominantly in roots. Immunolocalization studies indicate that GIP1 protein is mainly localized to the nucleus. In vitro electrophoretic mobility shift assays using an Adh G-box DNA probe and recombinant A. thaliana GBF3 or maize GBF1, showed that the presence of GIP1 resulted in a tenfold increase in GBF DNA binding activity without altering the migration, suggesting a transient association between GIP1 and GBF. Addition of GIP1 to intentionally aggregated GBF converted GBF to lower molecular weight macromolecular complexes and GIP1 also refolded denatured rhodanese in the absence of ATP. These data suggest GIP1 functions to enhance GBF DNA binding activity by acting as a potent nuclear chaperone or crowbar, and potentially regulates the multimeric state of GBFs, thereby contributing to bZIP-mediated gene regulation.

关键词： G-box binding factor interacting protein nuclear chaperone DNA binding affinity.

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Operations management for competitive advantage / Richard B. Chase, Nicholas j. Aquilano, F. robert j.cobs. 9th ed.

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丛书名： The Irwin/McGraw-Hill series. Operations and decision sciences.

2001年

作者： Richard B. Chase Nicholas j. Aquilano F. robert j.cobs.

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X-ray Multiple Diffraction Topographic Imaging Technique For Growth History Study of Habit Modifying Impurity Doped Crystals

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Chemical Research in Chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA C. K. j. robert M. C. Miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification Crystal growth Growth defects

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Development of a multivariate empirical model for predicting weak rock mass modulus

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International j.urnal of Mining Science and Technology 2015年第4期25卷 545-552页

作者： Kallu Raj.R. Keffeler Evan R. Watters robert j. Agharazi Alireza Department of Mining Engineering University of Nevada RESPEC Consulting and Services University of Nevada Itasca Houston Inc.

Estimating weak rock mass modulus has historically proven difficult although this mechanical property is an important input to many types of geotechnical analyses. An empirical database of weak rock mass modulus with associated detailed geotechnical parameters was assembled from plate loading tests per- formed at underground mines in Nevada, the Bakhtiary Dam proj.ct, and Portugues Dam proj.ct. The database was used to assess the accuracy of published single-variate models and to develop a multivari- ate model for predicting in-situ weak rock mass modulus when limited geoteehnical data are available. Only two of the published models were adequate for predicting modulus of weak rock masses over lim- ited ranges of alteration intensities, and none of the models provided good estimates of modulus over a range of geotechnical properties. In light of this shortcoming, a multivariate model was developed from the weak rock mass modulus dataset, and the new model is exponential in form and has the following independent variables：（1） average block size or j.int spacing, （2） field estimated rock strength, （3） dis- continuity roughness, and （4） discontinuity infilling hardness. The multivariate model provided better estimates of modulus for both hard-blocky rock masses and intensely-altered rock masses.

关键词： In-situ modulus Weak rock mass Preliminary design Elastic deformation

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Plant Carbonic Anhydrases： Structures, Locations, Evolution, and Physiological Roles

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Molecular Plant 2017年第1期10卷 30-46页

作者： robert j. DiMario Harmony Clayton Ananya Mukhedee Martha Ludwig j.mes V. Moroney Department of Biological Sciences Louisiana State University Baton Rouge LA 70803 USA School of Chemistry and Biochemistry University of Western Australia Perth WA 6009 Australia

Carbonic anhydrases （CAs） are zinc metalloenzymes that catalyze the interconversion of CO2 and HCO3- and are ubiquitous in nature. Higher plants contain three evolutionarily distinct CA families, αCAs, 13CAs, and γCAs, where each family is represented by multiple isoforms in all species. Alternative splicing of CA transcripts appears common; consequently, the number of functional CA isoforms in a species may exceed the number of genes. CAs are expressed in numerous plant tissues and in different cellular locations. The most prevalent CAs are those in the chloroplast, cytosol, and mitochondria. This diversity in location is paralleled in the many physiological and biochemical roles that CAs play in plants. In this review, the number and types of CAs in C3, C4, and crassulacean acid metabolism （CAM） plants are considered, and the roles of the α and yCAs are briefly discussed. The remainder of the review focuses on plant βCAs and includes the identification of homologs between species using phylogenetic approaches, a consideration of the inter- and intracellular localization of the proteins, along with the evidence for alternative splice forms. Current understanding of βCA tissue-specific expression patterns and what controls them are reviewed, and the physiological roles for which βCAs have been implicated are presented.

关键词： carbonic anhydrase regulation alternative splicing physiological role

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Is plate tectonics needed to evolve technological species on exoplanets?

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Geoscience Frontiers 2016年第4期7卷 573-580页

作者： robert j.Stern Geoscience Department University of Texas at Dallas

As we continue searching for exoplanets, we wonder if life and technological species capable of communicating with us exists on any of them. As geoscientists, we can also wonder how important is the presence or absence of plate tectonics for the evolution of technological species. This essay considers this question, focusing on tectonically active roclw （silicate） planets, like Earth, Venus, and Mars. The development of technological species on Earth provides key insights for understanding evolution on exoplanets, including the likely role that plate tectonics may play. An Earth-sized silicate planet is likely to experience several tectonic styles over its lifetime, as it cools and its lithosphere thickens, strengthens, and becomes denser. These include magma ocean, various styles of stagnant lid, and perhaps plate tectonics. Abundant liquid water favors both life and plate tectonics. Ocean is required for early evolution of diverse single-celled organisms, then colonies of cells which specialized further to form guts, ap- pendages, and sensory organisms up to the complexity of fish （central nervous system, appendages, eyes）. Large expanses of dry land also begin in the ocean, today produced above subduction zones in j.venile arcs and by their coalescence to form continents, although it is not clear that plate tectonics was required to create continental crust on Earth. Dry land of continents is required for further evolution of technological species, where modification of appendages for grasping and manipulating, and improve- ment of eyes and central nervous system could be perfected. These bioassets allowed intelligent crea- tures to examine the night sky and wonder, the beginning of abstract thinking, including religion and science. Technology arises from the exigencies of daily living such as tool-making, agriculture, clothing, and weapons, but the pace of innovation accelerates once it is allied with science. Finally, the importance of plate tectonics for devel

关键词： Plate tectonics Exoplanets Planetary science Intelligent life

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Weight measurement using image-based pose analysis

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Progress in Natural Science:Materials International 2008年第12期18卷 1507-1512页

作者： robert j.Sclabassi Laboratory for Computational Neuroseience Departments of NeurosurgeryElectrical & Computer Engineeringand BioengineeringUniversity of PittsburghPittsburgh 15213USA

Image-based gait analysis as a means of biometric identification has attracted much research *** of the existing methods focus on human identification,posture analysis and movement *** have been few investigations on measuring the carried load based on the carrier’s gait characteristics by automatic image ***,this measurement is very useful in a number of applications,such as the study of the carried load on the postural development of children and *** this paper,we inves- tigate how to automatically estimate the carried weight from a sequence of *** present a method to extract human gait silhouette based on an observation that humans tend to minimize the energy during *** compute several angles of body leaning and deter- mine the relationship of the carried weight,the leaning angles and the centroid location according to a human kinetic *** weight determination method has been verified successfully by experiments.

关键词： Image-based pose analysis Energy minimization Pattern recognition Load carrying measurement

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