Characterization of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced modification of hepatic pyruvate carboxylase gene expression in C57BL/6J male mice

The effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure on hepatic pyruvate carboxylase (PC) gene expression were investigated in C57BL/6J Ah[superscipt b/b male mice. A dose-dependent reduction of PC levels and activity occurred in animals given a single intraperitoneal dose of TCDD in a corn oil carrier. The dose ranged from 1 to 75 ug/kg body weight and the analysis performed 8 days postinjection. At the maximum TCDD level investigated, a 10-fold reduction in PC activity occurred. At doses beyond those required to initiate a reduction in PC, a lactate dehydrogenase isozyme patterns shift is observed. This is accompanied by increases in blood lactic acid levels. Northern blot analysis on RNA extracts from hepatic tissues indicated that at 8 days post TCDD treatment, a dose-dependent reduction of hepatic mRNA levels occurs. The aryl hydrocarbon receptor (AhR) is believed to mediate all responses to TCDD. Liganded AhR and the aryl hydrocarbon receptor nuclear translocator (ARNT) protein form a heterodimeric transcription factor which interacts with dioxin response elements (DREs). These are found in enhancer/promoter regions of many genes that respond transcriptionally to TCDD exposure. Cloning and sequencing a region approximately 1.4 kb upstream of the PC translational start site revealed an untranslated leader sequence of 124 nucleotides starting with adenosine. Primary structural analysis of the upstream region revealed an 1nr element in place of a TATA element. Additional transcription factor elements were identified including: Spl, GCF, UBP-1, GRE, CREB, NF-1, HNF-4, TFII-I and E-boxes; DRE elements were notably lacking. A tandem series of 10 evenly spaced E-boxes, which bind ARNT homodimers, are each juxtaposed to a TFII-I element, possibly forming composite elements. Tertiary structure analysis revealed the positioning of nine composite elements displayed as a trio of phased elements. Transient transfections into Hepa lc1c7 cells, using a luciferase reporter gene under the transcriptional control of the PC upstream region, unlike the animal studies, produced an induction in activity in the presence of 10 nM TCDD. Co-transfections with an ARNT encoding plasmid reduced induction indicating overexpression of ARNT protein partially overrides the TCDD-induced increase in activity. These results in relationship to whole animal experiments are discussed

HRM, organizational capacity for change, and performance: a global perspective

This special issue brings together a variety of articles, each one enriching understanding about whether and how human resource management (HRM) influences organizational performance (however defined) against a backdrop of complex change. We present a preliminary framework that enables us to integrate the diverse themes explored in the special issue, proposing a mediating role for organizational change capacity (OCC). OCC represents a particular subset within the resource- based literature labeled as “dynamic capabilities.” Although not well researched, there is evidence that OCC is positively associated with firm performance and that this relationship is stronger given conditions of high uncertainty. Our framework reflects on external and internal parameters, which we suggest moderate the relationship between human resource management (HRM), OCC, and organizational performance. Our intention is to provide compelling insight for both practitioners and researchers, especially those whose remit extends beyond national boundaries, with reference to areas of the globe as disparate as Greece, Ireland, Pakistan, Switzerland, and the United Kingdom

Dynamic capabilities and knowledge management: an integrative role for learning?

Modern strategic management theories try to explain why firms differ, because new sources of competitive advantage are keenly sought in the dynamic and complex environment of global competition. Two areas in particular have attracted the attention of researchers: the role of dynamic capabilities, and the firm's abilities for knowledge management. In this paper, we argue that there is a link between these two concepts, which has not been fully articulated in the literature. The aim of the paper is therefore to ascertain the conceptual connection between them as a basis for future research. Our proposed framework acknowledges and critiques the distinct roots of each field, identifies boundaries, and proposes relationships between the constructs and firm performance

Talent management motives and practices in an emerging market: A comparison between MNEs and local firms

This paper compares the differences in talent management motivations and practices between MNEs and local firms in the emerging market of Turkey. It uses institutional theory and the resource based view of the firm to explain these differences. Examining data from 201 firms the findings show significant differences between the talent management motives of MNEs and local firms, with MNEs having more tactical motivations for their talent management systems. The study also shows significant differences in the talent management practices between MNEs and local firms, with MNEs implementing more robust systems of talent management overall. The findings indicate that the motives for TM and the practices that are pursued by organizations are society-bound. The study of TM motives and practices has to be framed within the context of the institution as this shapes the way in which actors perceive and respond to environmental and organizational stimuli and the extent to which they seek to protect the rules that shape and structure their environments

WHO preferred product characteristics for monoclonal antibodies for passive immunization against respiratory syncytial virus (RSV) disease in infants - Key considerations for global use.

World Health Organization (WHO) preferred product characteristics describe preferences for product attributes that would help optimize value and use to address global public health needs, with a particular focus on low- and middle-income countries. Having previously published preferred product characteristics for both maternal and paediatric respiratory syncytial virus (RSV) vaccines, WHO recently published preferred product characteristics for monoclonal antibodies to prevent severe RSV disease in infants. This article summarizes the key attributes from the preferred product characteristics and discusses key considerations for future access and use of preventive RSV monoclonal antibodies

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

The azimuthal anisotropy of charged particles in PbPb collisions at nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pt) range up to approximately 60 GeV. The data cover both the low-pt region associated with hydrodynamic flow phenomena and the high-pt region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with pt, reaching a maximum around pt = 3 GeV, and then to gradually decrease to almost zero, with the decline persisting up to at least pt = 40 GeV over the full centrality range measured.Comment: Replaced with published version. Added journal reference and DO