Identification of stable endogenous reference genes for real-time PCR in the human fetal gonad using an external standard technique

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Changes in Managerial Pay Structures 1986-1992 and Rising Returns to Skill

We examine the relationship between wages and skill requirements in a sample of over 50,000 managers in 39 companies between 1986 and 1992. The data include an unusually good measure of job requirements and skills that can proxy for human capital. We find that wage inequality increased both within and between firms from 1986 and 1992. Higher returns to our measure of skill accounts for most of the increasing inequality within firms. At the same time, our measure of skill does not explain much of the cross-sectional variance in average wages between employers, and changes in returns to skill do not explain any of the time series increase in between-firm variance over time. Finally, we find only weak evidence of any declines in the rigidity of internal wage structures of large employers.

Management Jobs in the Insurance Industry: Organizational Deskilling and Rising Pay Inequality

The attention of both the research community and the popular press has begun to shift from a traditional focus on production jobs and toward management positions in part because of a perception that a fundamental change is underway in the management ranks. Unlike the temporary layoffs of production workers that were historically driven by business cycles, the changes in management job security seem to be permanent and, in large measure, driven by development inside the firm. The most important of these forces appear to be changes in the structure of management and in the organization of work processes. The authors use a unique set of data to examine the structure of management jobs among a sample of companies and observe how those jobs have changed over time. They examine changes in the skill requirements of jobs by functional area and by level in the organization, changes in the "shape" of the organization chart - the distribution of employees across management job titles - and changes in compensation for these jobs. The data were obtained from Hay Associates, and it included the internal organization of management jobs for 11 life insurance companies. The authors see a sharp expansion in the proportion of line workers, absolute declines in the number of top management positions, and only modest growth in the number of middle managers and supervisors. As a result the organization chart has changed dramatically in these companies, becoming considerably flatter. The "span of control" has increased for every level of the organization and especially for first level management. If the widening of the supervisory span of control resulted from taking decision making and responsibility from supervisors and pushing it down to line workers, it does not seem to have increased the average skill requirements of the exempt line workers. Skill requirements for the other levels rose over the period, especially for top management positions. Overall, the average level of skill in the sample fell substantially between 1986 and 1992 (even though skills rose in two of the four levels) because of a sharp shift in the distribution of employment away from management and toward line positions. The authors suggest that the best description of these patterns is that they represent upskilling of individual jobs and deskilling of organizations. Regarding compensation, none of the levels experienced increases in skill that were statically significant, but top managers received a large (28 percent) increase in pay, middle managers received a modest (10 percent) increase, and the lower two levels received virtually no increases. One conclusion is that earnings inequality is increasing substantially inside these firms in a manner that is not attributable to any increase in skill, and the dividing line for that growth in inequality is no longer exempt/nonexempt but supervisor/manager. A possible explanation for the rising inequality in compensation is that it helps offset change in the probability of promotion. The fact that the span of control is increasing and organizational chart flattening means that the probability of the average worker being promoted is declining. The decline in the probability of promotion might reduce the incentives to work hard. Increases in the compensation of top jobs increase the return to securing a promotion and may offset some of the effect produced by the decline in the probability of promotion. Another explanation is that top mangers are in "better positions to legislate their own pay increases." If true, this sample may actually underrepresent the true extent of income inequality because it consists of companies using an external consultant to help set compensation where internal consistency is an important characteristic of the pay system. These results suggest that "management" as a career will remain attractive, albeit less certain in terms of promotion prospects. Shifts to team-based approaches and the elimination of functional designations would suggest a greater need for generalists than specialists. As technology such as expert systems reduces the need for large units of "experts," the manger's skill will be in recognizing when an expert needs to be called. Leadership skills and the ability to adapt to a changing environment are two qualities that will be sought in the future. Fortunately, these skills will also be useful to team members who are not selected for promotion to mangers. Increasing income inequality may lead to distrust within the organization, though this may be offset by the technical tracks that allow highly skilled non-managers to earn equivalent levels of pay. The fact that insurance companies are relatively unique in facing no major industry-specific shocks from the outside environment suggests that these results should translate well to organizations in other industries.

Effect of live yeast culture supplementation on fibrolytic and saccharolytic bacterial populations in the feces of horses fed a high-fiber or high-starch diet

The objective of this study was to assess the effect of live yeast (Saccharomyces cerevisiae) supplementation on the populations of specific cellulolytic (Fibrobacter succinogenes and Ruminococcus flavefaciens) and saccharolytic (Streptococcus equinus and Streptococcus bovis) bacteria in the feces of horses fed high-starch and high-fiber diets. Four horses were each fed diets consisting of high fiber with no yeast (HF), high fiber with yeast (HFY), high starch with no yeast (HS), and high starch with yeast (HSY) in a 4 × 4 Latin-square design study. Fresh fecal samples were collected on the last 3 days of each 31-day experimental period and were then assessed, using semiquantitative real-time PCR, for total bacterial load and levels of target bacterial species, relative to the total bacterial load. The most abundant of the target species was F. succinogenes, and the HSY diet resulted in a significant (P = .045) reduction in relative levels of this bacterium. No significant effect (P = .224) of diet was observed in relation to abundance of R. flavefaciens. Results show that diet did not have a significant (P = .068) effect on relative quantities of S. equinus, although there appeared to be a trend for increased levels of this bacterium during feeding of high-starch diets. Numbers of S. bovis were higher (P < .001) when horses were fed HS and HSY diets than when fed the HF and HFY diets. Significant variation in levels of S. equinus (P = .024) and S. bovis (P = .049) was observed between individual horses

Comment on “Effects of Arsenite during Fetal Development on Energy Metabolism and Susceptibility to Diet-Induced Fatty Liver Diseases in Male Mice” and “Mechanisms Underlying Latent Disease Risk Associated with Early-Life Arsenic Exposure: Current Trends and Scientific Gaps”

Peer reviewedPublisher PD

Nutrient transporter expression in both the placenta and fetal liver are affected by maternal smoking

ACKNOWLEGDEMENTS Authors would like to thank the nurses of ward 309 (Aberdeen Royal Infirmary) for consenting participants and NHS Grampian Biorepository staff. Also, Gary Cameron for performing the LC-MS/MS cotinine analyses and Ms Linda Robertson for technical assistance. The authors state there are no conflicts of interest. Author contributions: NW, PF and PAF designed the research; NW conducted research, analysed data and wrote paper; PAF responsible for ethics (SAFeR study). All authors read and approved the final manuscript. Authors would like to thank the study funders: Glasgow Children’s Hospital Charity YRSS/PHD/2016/05 and UK Medical Research Council: MR/L010011/1, to PAF & PJOS and MR/P011535/1 to PAF. The funders played no role in the conduct, analysis or publication of the studyPeer reviewedPublisher PD

Novel model for end-neuroma formation in the amputated rabbit forelimb

<p>Abstract</p> <p>Background</p> <p>The forelimb amputee poses many reconstructive challenges in the clinical setting, and there is a paucity of established surgical models for study. To further elucidate the pathogenic process in amputation neuroma formation, we created a reproducible, well-tolerated rabbit forelimb amputation model.</p> <p>Methods</p> <p>Upon approval from the Institutional Animal Care and Use Committee, 5 New Zealand White rabbits underwent left forelimb amputation. During this initial surgery, the median, radial and ulnar nerves were transected 1.6-2.5 (mean 2.0) cm distal to the brachial plexus, transposed onto the anterior chest wall and preserved at length. Six weeks subsequent to the amputation, the distal 5 mm of each neuroma was excised, and the remaining stump underwent histomorphometric analysis.</p> <p>Results</p> <p>The nerve cross sectional areas increased by factors of 1.99, 3.17, and 2.59 in the median (p = 0.077), radial (p < 0.0001) and the ulnar (p = 0.0026) nerves, respectively. At the axonal level, the number and cross-sectional area of myelinated fibers demonstrated an inverse relationship whereby the number of myelinated fibers in the median, radial and ulnar nerves increased by factors of 5.13 (p = 0.0043), 5.25 (p = 0.0056) and 5.59 (p = 0.0027), and the cross-sectional areas of these myelinated fibers decreased by factors of 4.62 (p < 0.001), 3.51 (p < 0.01), and 4.29 (p = 0.0259), respectively.</p> <p>Conclusion</p> <p>Given that the surgical model appears well-tolerated by the rabbits and that patterns of morphologic change are consistent and reproducible, we are encouraged to further investigate the utility of this model in the pathogenesis of neuroma formation.</p

Placental transporter localization and expression in the Human : the importance of species, sex, and gestational age differences

Grant Support: This work was supported by the Medical Research Council, UK (MR/L010011/1 to PAF, PJOS) and a Glasgow Children's Hospital Charity Research Fund and University of Aberdeen, UK, Elphinstone Scholarship to NW.Peer reviewedPublisher PD

Effects of copper nanoparticle exposure on host defense in a murine pulmonary infection model

<p>Abstract</p> <p>Background</p> <p>Human exposure to nanoparticles (NPs) and environmental bacteria can occur simultaneously. NPs induce inflammatory responses and oxidative stress but may also have immune-suppressive effects, impairing macrophage function and altering epithelial barrier functions. The purpose of this study was to assess the potential pulmonary effects of inhalation and instillation exposure to copper (Cu) NPs using a model of lung inflammation and host defense.</p> <p>Methods</p> <p>We used <it>Klebsiella pneumoniae </it>(<it>K.p.</it>) in a murine lung infection model to determine if pulmonary bacterial clearance is enhanced or impaired by Cu NP exposure. Two different exposure modes were tested: sub-acute inhalation (4 hr/day, 5 d/week for 2 weeks, 3.5 mg/m³) and intratracheal instillation (24 hr post-exposure, 3, 35, and 100 μg/mouse). Pulmonary responses were evaluated by lung histopathology plus measurement of differential cell counts, total protein, lactate dehydrogenase (LDH) activity, and inflammatory cytokines in bronchoalveolar lavage (BAL) fluid.</p> <p>Results</p> <p>Cu NP exposure induced inflammatory responses with increased recruitment of total cells and neutrophils to the lungs as well as increased total protein and LDH activity in BAL fluid. Both inhalation and instillation exposure to Cu NPs significantly decreased the pulmonary clearance of <it>K.p.</it>-exposed mice measured 24 hr after bacterial infection following Cu NP exposure versus sham-exposed mice also challenged with <it>K.p </it>(1.4 × 10⁵bacteria/mouse).</p> <p>Conclusions</p> <p>Cu NP exposure impaired host defense against bacterial lung infections and induced a dose-dependent decrease in bacterial clearance in which even our lowest dose demonstrated significantly lower clearance than observed in sham-exposed mice. Thus, exposure to Cu NPs may increase the risk of pulmonary infection.</p