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New Cluster (new + cluster)
Selected AbstractsSourcing Research as an Intellectual Network of Ideas,DECISION SCIENCES, Issue 3 2008G. Tomas M. Hult ABSTRACT What are the current intellectual clusters in the sourcing literature? How do these clusters relate to each other? How has sourcing-related research changed over the last 10 years? We respond to these questions by examining the intellectual structure of research in the sourcing literature across 21 journals during the last decade (1998,2007). Multidimensional scaling is used to analyze cocitation data involving 72,003 citations from 1,960 sourcing articles. The results indicate that 10 different sourcing clusters emerged in the 1998,2002 period and 6 sourcing clusters surfaced in the 2003,2007 period. Five of the intellectual clusters in 1998,2002 disappeared in 2003,2007, five clusters remained, and one new cluster materialized in 2003,2007 that did not exist in the earlier period (Managerial Behavior and Upstream Decision Making). [source] Exporting the German Model: The Establishment of a New Automobile Industry Cluster in ShanghaiECONOMIC GEOGRAPHY, Issue 1 2005Heiner Depner Abstract: Recent work has provided evidence that the establishment of new industry clusters cannot be jump-started through policy initiatives alone. This evidence does not imply, however, that the genesis of a new cluster cannot be planned at all. Especially in the context of a developing economy, it seems useful to reinvestigate the relation among economic development, the strategies of multinational firms, and state intervention in this respect. Drawing from the case of the automobile industry and its supplier system in Shanghai in which German firms play an important role, we provide empirical evidence of the evolution of a new cluster that is supported by the state in various forms and characterized by a focal, hierarchically structured production system. We use a multidimensional approach to clusters, which leads to a more nuanced understanding of the evolution and growth of a cluster than that provided by earlier accounts. This approach allows us to distinguish the development of the Shanghai automobile industry cluster along its vertical, horizontal, external, institutional, and power dimensions. We provide evidence that another dimension,"culture",plays an important role, especially in its relation to issues of power and institutions. The role of this dimension is demonstrated in the case of German firms, which tap into the Chinese innovation system. This system is characterized by particular business relations, institutions, norms, and various social practices that are new to German firms. We demonstrate how this difference creates problems in establishing local production and supplier relations and how these problems can be overcome. [source] Vertical profiles of methanogenesis and methanogens in two contrasting acidic peatlands in central New York State, USAENVIRONMENTAL MICROBIOLOGY, Issue 8 2006Hinsby Cadillo-Quiroz Summary Northern acidic peatlands are important sources of atmospheric methane, yet the methanogens in them are poorly characterized. We examined methanogenic activities and methanogen populations at different depths in two peatlands, McLean bog (MB) and Chicago bog (CB). Both have acidic (pH 3.5,4.5) peat soils, but the pH of the deeper layers of CB is near-neutral, reflecting its previous existence as a neutral-pH fen. Acetotrophic and hydrogenotrophic methanogenesis could be stimulated in upper samples from both bogs, and phylotypes of methanogens using H2/CO2 (Methanomicrobiales) or acetate (Methanosarcinales) were identified in 16S rRNA gene clone libraries and by terminal restriction fragment length polymorphism (T-RFLP) analyses using a novel primer/restriction enzyme set that we developed. Particularly dominant in the upper layers was a clade in the Methanomicrobiales, called E2 here and the R10 or fen group elsewhere, estimated by quantitative polymerase chain reaction to be present at ,108 cells per gram of dry peat. Methanogenic activity was considerably lower in deeper samples from both bogs. The methanogen populations detected by T-RFLP in deeper portions of MB were mainly E2 and the uncultured euryarchaeal rice cluster (RC)-II group, whereas populations in the less acidic CB deep layers were considerably different, and included a Methanomicrobiales clade we call E1-E1,, as well as RC-I, RC-II, marine benthic group D, and a new cluster that we call the subaqueous cluster. E2 was barely detectable in the deeper samples from CB, further evidence for the associations of most organisms in this group with acidic habitats. [source] Mitochondrial diversity of native pigs in the mainland South and South-east Asian countries and its relationships between local wild boarsANIMAL SCIENCE JOURNAL, Issue 4 2008Kazuaki TANAKA ABSTRACT In this study, we analyzed DNA sequence of mitochondrial DNA (mtDNA) control regions on the 130 native domestic pigs and eight wild boars in the mainland South and South-east Asian countries including Bhutan, Cambodia, Laos, Myanmar, and Vietnam. Forty-four haplotypes were found in the 138 individuals, 41 were in the domestic and four were in wild boars. Only one haplotype was shared by domestic and wild population in Bhutan. In other cases, mtDNA of wild boars did not show close affinity to that of the domestic pigs in the same location, indicating that the native domestic pigs in these countries did not originate in the present habitat. Phylogenetic analyzes of mtDNA haplotypes recapitulated several major clusters identified in other studies, but 11 haplotypes were grouped in a new cluster we named MTSEA. In most cases, more than one lineage group were present in a sampling station, indicating that the present indigenous domestic pigs may have multiple origins. The MTSEA haplotypes were present in relatively high frequencies in domestic pigs in the mountainous area of mainland South-east Asia (Cambodia and Laos), with a few found in Myanmar and Bhutan. The distributions of MTSEA haplotypes are in great conformity with the distribution of present-day Mon-Khmer language and indicated the existence of yet another independent domestication. The D2 haplotypes that distribute high frequency (almost 100%) throughout the Chinese breeds were dominant in Bhutan, Myanmar, and Vietnam. These results suggest an existence of human-mediated dispersal of domestic pigs from north to the south during the historical expansion of Sino-Tibetan and Tai peoples. The D3 haplotypes previously reported in north India were found in sympatric domestic and wild pigs in Bhutan. The D3 haplotype is an important proof of independent domestication event and/or great gene flow between wild and domestic pigs in the foot of Himalaya. [source] Synthesis and Characterization of Cubane-Like Cr4E4 (E = S, Se) Clusters , Molecular Structures of (,5 -RC5H4)4Cr4E4 (E = S, R = MeCO, MeO2C, EtO2C; E = Se, R = H)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2004Li-Cheng Song Abstract Treatment of the Cr,Cr singly-bonded dimers [,5 -RC5H4Cr(CO)3]2 (1, R = MeCO; 2, R = MeO2C; 3, R = EtO2C) with excess sulfur in refluxing THF gave the cubane Cr4S4 clusters (,5 -RC5H4)4Cr4S4 (4, R = MeCO; 5, R = MeO2C; 6, R = EtO2C). The cubane Cr4S4 cluster 4 reacted with excess 2,4-dinitrophenylhydrazine to produce the hydrazone derivative [,5,2,4-(NO2)2C6H3NHN=C(Me)C5H4]4Cr4S4 (7). The singly-bonded dimers of [,5 -RC5H4Cr(CO)3]2 (8, R = Me; 9, R = EtO2C), in the presence of excess selenium, reacted similarly to the linear Cr2Se complexes [,5 -RC5H4Cr(CO)2]2Se (10, R = Me; 11, R = EtO2C), which reacted with an equimolar quantity of selenium to afford the cubane Cr4Se4 clusters (,5 -RC5H4)4Cr4Se4 (12, R = Me; 13, R = EtO2C). A particularly interesting phenomenon is the cross-assembled reaction of the linear Cr2Se complexes [,5 -MeC(O)C5H4Cr(CO)2]2Se (14) and [CpCr(CO)2]2Se (15) in the presence of excess selenium in THF that gave rise to a series of cubane Cr4Se4 clusters [,5 -MeC(O)C5H4]nCp4,nCr4Se4 (16, n = 0; 17, n = 1; 18, n = 2; 19, n = 3; 20, n = 4). The possible pathway for the cross-assembled reaction is suggested. Furthermore the new clusters were characterized by elemental analysis and spectroscopy, and in the case of 4,6 and 16 also by X-ray diffraction techniques. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Adjusted Scaling of FDG Positron Emission Tomography Images for Statistical Evaluation in Patients With Suspected Alzheimer's DiseaseJOURNAL OF NEUROIMAGING, Issue 4 2005Ralph Buchert PhD ABSTRACT Background and Purpose. Statistical parametric mapping (SPM) gained increasing acceptance for the voxel-based statistical evaluation of brain positron emission tomography (PET) with the glucose analog 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) in patients with suspected Alzheimer's disease (AD). To increase the sensitivity for detection of local changes, individual differences of total brain FDG uptake are usually compensated for by proportional scaling. However, in cases of extensive hypometabolic areas, proportional scaling overestimates scaled uptake. This may cause significant underestimation of the extent of hypometabolic areas by the statistical test. Methods. To detect this problem, the authors tested for hyper metabolism. In patients with no visual evidence of true focal hypermetabolism, significant clusters of hypermetabolism in the presence of extended hypometabolism were interpreted as false-positive findings, indicating relevant overestimation of scaled uptake. In this case, scaled uptake was reduced step by step until there were no more significant clusters of hypermetabolism. Results. In 22 consecutive patients with suspected AD, proportional scaling resulted in relevant overestimation of scaled uptake in 9 patients. Scaled uptake had to be reduced by 11.1%± 5.3% in these cases to eliminate the artifacts. Adjusted scaling resulted in extension of existing and appearance of new clusters of hypometabolism. Total volume of the additional voxels with significant hypometabolism depended linearly on the extent of the additional scaling and was 202 ± 118 mL on average. Conclusions. Adjusted scaling helps to identify characteristic metabolic patterns in patients with suspected AD. It is expected to increase specificity of FDGPET in this group of patients. [source] Ultraluminous X-ray sources and star formationMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2004A. R. King ABSTRACT Chandra observations of the Cartwheel galaxy reveal a population of ultraluminous X-ray sources (ULXs) with lifetimes , 107 yr associated with a spreading wave of star formation which began some 3 × 108 yr ago. A population of high-mass X-ray binaries provides a simple model: donor stars of initial masses M2, 15 M, transfer mass on their thermal time-scales to black holes of masses M1, 10 M,. For alternative explanations of the Cartwheel ULX population in terms of intermediate-mass black holes (IMBHs) accreting from massive stars, the inferred production rate ,10,6 yr,1 implies at least 300 IMBHs, and more probably 3 × 104, within the star-forming ring. These estimates are increased by factors of ,,1 if the efficiency , with which IMBHs find companions of ,15 M, within 107 yr is <1. Current models of IMBH production would require a very large mass (,1010 M,) of stars to have formed new clusters. Further, the accretion efficiency must be low (, 6 × 10,3) for IMBH binaries, suggesting super-Eddington accretion, even though intermediate black hole masses are invoked with the purpose of avoiding it. These arguments suggest either that, to make a ULX, an IMBH must accrete from some as yet unknown non-stellar mass reservoir with very specific properties, or that most if not all ULXs in star-forming galaxies are high-mass X-ray binaries. [source] | ||||||||||