1,388 research outputs found
Is there evidence to support Porter-type policies?
The paper examines the views, often associated with Porter, that clusters with deep collaborative networks
and established local supply chains have good performance. The view that good cluster performance is not connected to the industrial
sector is also assessed. Data from a Department of Trade and Industry (DTI) study on UK clusters are used to assess the impact on
performance (employment growth and international competitiveness) of cluster depth, the stage of development of local supply
chains, and industrial sector. The results of the analysis of the DTI data on clusters do not provide strong support for Porter-type
views on cluster policy. Although established clusters are linked to employment growth, deep clusters are not associated with employment
growth or international competitiveness, and clusters in the services, and media, computer-related and biotechnology sectors
are more likely than manufacturing clusters to have good performance. Some of the major policy implications of the results are discussed
in the light of the literature on the importance of regional, national, and international networks for the performance of clusters
B553: Consumer Packages for Maine Mcintosh Apples
Three kinds of consumer packages for apples were developed for testing in the 1955-56 marketing season. In developing these packages, the authors modified the jumble-pack, polyethylene package in a way that would protect the fruit from most of the bruising and still maintain almost complete visibility of the fruit. One consumer package developed was a long narrow polyethylene bag, another was a polyethylene bag with a divider insert, and the third package had a cell partition placed in a similar plastic bag. All three packages were well accepted by consumers in the Portland market.https://digitalcommons.library.umaine.edu/aes_bulletin/1085/thumbnail.jp
A study of rotating globular clusters - the case of the old, metal-poor globular cluster NGC 4372
Aims: We present the first in-depth study of the kinematic properties and
derive the structural parameters of NGC 4372 based on the fit of a Plummer
profile and a rotating, physical model. We explore the link between internal
rotation to different cluster properties and together with similar studies of
more GCs, we put these in the context of globular cluster formation and
evolution. Methods: We present radial velocities for 131 cluster member stars
measured from high-resolution FLAMES/GIRAFFE observations. Their membership to
the GC is additionally confirmed from precise metallicity estimates. Using this
kinematic data set we build a velocity dispersion profile and a systemic
rotation curve. Additionally, we obtain an elliptical number density profile of
NGC 4372 based on optical images using a MCMC fitting algorithm. From this we
derive the cluster's half-light radius and ellipticity as r_h=3.4'+/-0.04' and
e=0.08+/-0.01. Finally, we give a physical interpretation of the observed
morphological and kinematic properties of this GC by fitting an axisymmetric,
differentially rotating, dynamical model. Results: Our results show that NGC
4372 has an unusually high ratio of rotation amplitude to velocity dispersion
(1.2 vs. 4.5 km/s) for its metallicity. This, however, puts it in line with two
other exceptional, very metal-poor GCs - M 15 and NGC 4590. We also find a mild
flattening of NGC 4372 in the direction of its rotation. Given its old age,
this suggests that the flattening is indeed caused by the systemic rotation
rather than tidal interactions with the Galaxy. Additionally, we estimate the
dynamical mass of the GC M_dyn=2.0+/-0.5 x 10^5 M_Sun based on the dynamical
model, which constrains the mass-to-light ratio of NGC 4372 between 1.4 and 2.3
M_Sun/L_Sun, representative of an old, purely stellar population.Comment: Accepted for publication in A&A, 12 pages, 14 figures, 2 table
A case-cohort study of human herpesvirus 8 seropositivity and incident prostate cancer in Tobago
<p>Abstract</p> <p>Background</p> <p>We previously reported a cross-sectional association between the presence of human herpesvirus 8 (HHV-8) serum antibodies and screen-detected prostate cancer in men living in Tobago. In the same study population, we examined the association between HHV-8 seropositivity and incident prostate cancer discovered at later screenings.</p> <p>Methods</p> <p>In 40-81 year-old men without prostate cancer discovered at initial digital rectal examination (DRE) and prostate-specific antigen (PSA) screening, a case-cohort design measured the association between baseline HHV-8 seropositivity (modified immunofluorescence assay for antibodies against HHV-8 lytic antigens) and incident prostate cancer detected at DRE and PSA screenings three or five years later.</p> <p>Results</p> <p>Analyses included 486 unique individuals, 96 incident prostate cancer cases, and 415 randomly selected subjects representing an at-risk cohort. By design, the random sub-cohort contained 25 incident prostate cancer cases. In the sub-cohort, the frequency of HHV-8 seropositivity increased across age groupings (40-49 years: 3.5%, 50-59 years: 13.6%, and ā„ 60 years: 22.9%). HHV-8 seropositivity was higher in men with elevated (ā„ 4.0 ng/mL) than men with non-elevated PSA at initial screening (30.4% <it>vs</it>. 9.9% seropositive; crude odds ratio (OR) 3.96, 95% confidence interval (CI) 1.53-10.2; age-adjusted OR 2.42, 95% CI 0.91-6.47). HHV-8 seropositivity did not increase incident prostate cancer risk (age-adjusted hazard ratio (HR) 0.88, 95% CI 0.46-1.69).</p> <p>Conclusions</p> <p>Case-cohort analysis did not identify association between HHV-8 seropositivity and incident prostate cancer. However, analyses uncovered possible association between HHV-8 and PSA (a marker of prostate inflammation). Co-occurrence of HHV-8 seropositivity and PSA elevation may explain cross-sectional association between HHV-8 and PSA screen-detected prostate cancer.</p
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The impact of autonomy and organisational relationships on subsidiary employment of skilled labour
The paper develops a conceptual model on relationship between the strategic development of subsidiaries, in developed economies, and the development of higher valued operations that leads to increased employment of skilled labour. A concept of effective autonomy is developed in the paper. Effective autonomy is conceived as the ability of the subsidiary to implement and finance its desired increase in skilled labour. The interrelated effects between effective autonomy and intra and inter organisational relationships and employment of skilled labour are found to be uncertain because effective autonomy can be supportive of the development of intra and inter organisational relationships that requires a higher proportion of skilled labour, but effective autonomy can lead to deterioration in intra-organisational relationships thereby leading to a more peripheral role played by the subsidiary thus lowering the need for skilled employment. The conceptual model is based on changes in effective autonomy and intra and inter organisational relationships and is therefore set in the context of the evolution of the development of subsidiaries
Selection of tuning parameters in bridge regression models via Bayesian information criterion
We consider the bridge linear regression modeling, which can produce a sparse
or non-sparse model. A crucial point in the model building process is the
selection of adjusted parameters including a regularization parameter and a
tuning parameter in bridge regression models. The choice of the adjusted
parameters can be viewed as a model selection and evaluation problem. We
propose a model selection criterion for evaluating bridge regression models in
terms of Bayesian approach. This selection criterion enables us to select the
adjusted parameters objectively. We investigate the effectiveness of our
proposed modeling strategy through some numerical examples.Comment: 20 pages, 5 figure
Role of interferonāĪ³ and inflammatory monocytes in driving colonic inflammation during acute Clostridium difficile infection in mice
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136491/1/imm12700.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136491/2/imm12700_am.pd
The pancreatic Ī² cell is a key site for mediating the effects of leptin on glucose homeostasis
SummaryThe hormone leptin plays a crucial role in maintenance of body weight and glucose homeostasis. This occurs through central and peripheral pathways, including regulation of insulin secretion by pancreatic Ī² cells. To study this further in mice, we disrupted the signaling domain of the leptin receptor gene in Ī² cells and hypothalamus. These mice develop obesity, fasting hyperinsulinemia, impaired glucose-stimulated insulin release, and glucose intolerance, similar to leptin receptor null mice. However, whereas complete loss of leptin function causes increased food intake, this tissue-specific attenuation ofĀ leptin signaling does not alter food intake or satiety responses to leptin. Moreover, unlike other obese models, these mice have reduced fasting blood glucose. These results indicate that leptin regulation of glucose homeostasis extends beyond insulin sensitivity to influence Ī² cell function, independent of pathways controlling food intake. These data suggest that defects in this adipoinsular axis could contribute to diabetes associated with obesity
129-derived Strains of Mice Are Deficient in DNA Polymerase Ī¹ and Have Normal Immunoglobulin Hypermutation
Recent studies suggest that DNA polymerase Ī· (polĪ·) and DNA polymerase Ī¹ (polĪ¹) are involved in somatic hypermutation of immunoglobulin variable genes. To test the role of polĪ¹ in generating mutations in an animal model, we first characterized the biochemical properties of murine polĪ¹. Like its human counterpart, murine polĪ¹ is extremely error-prone when catalyzing synthesis on a variety of DNA templates in vitro. Interestingly, when filling in a 1 base-pair gap, DNA synthesis and subsequent strand displacement was greatest in the presence of both pols Ī¹ and Ī·. Genomic sequence analysis of Poli led to the serendipitous discovery that 129-derived strains of mice have a nonsense codon mutation in exon 2 that abrogates production of polĪ¹. Analysis of hypermutation in variable genes from 129/SvJ (Poliā/ā) and C57BL/6J (Poli+/+) mice revealed that the overall frequency and spectrum of mutation were normal in polĪ¹-deficient mice. Thus, either polĪ¹ does not participate in hypermutation, or its role is nonessential and can be readily assumed by another low-fidelity polymerase
A Powerful AGN Outburst in RBS 797
Utilizing ks of Chandra X-ray Observatory imaging, we present an
analysis of the intracluster medium (ICM) and cavity system in the galaxy
cluster RBS 797. In addition to the two previously known cavities in the
cluster core, the new and deeper X-ray image has revealed additional structure
associated with the active galactic nucleus (AGN). The surface brightness
decrements of the two cavities are unusually large, and are consistent with
elongated cavities lying close to our line-of-sight. We estimate a total AGN
outburst energy and mean jet power of erg and
erg s, respectively, depending on the
assumed geometrical configuration of the cavities. Thus, RBS 797 is apparently
among the the most powerful AGN outbursts known in a cluster. The average mass
accretion rate needed to power the AGN by accretion alone is
yr. We show that accretion of cold gas onto the AGN at this level is
plausible, but that Bondi accretion of the hot atmosphere is probably not. The
BCG harbors an unresolved, non-thermal nuclear X-ray source with a bolometric
luminosity of erg s. The nuclear emission is
probably associated with a rapidly-accreting, radiatively inefficient accretion
flow. We present tentative evidence that star formation in the BCG is being
triggered by the radio jets and suggest that the cavities may be driving weak
shocks () into the ICM, similar to the process in the galaxy
cluster MS 0735.6+7421.Comment: Accepted to ApJ; 20 pages, 11 low-resolution figure
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