ω(→π+π−π0) \omega (\to \pi^+\pi^-\pi^0) meson photoproduction on proton

The cross section is estimated for the $\pi^+\pi^-\pi^0$ invariant mass distribution in the $\gamma p$ reaction in the GeV region. This reaction is assumed to proceed through the formation of the $\omega$ meson in the intermediate state, since the production cross section for this meson in the $\gamma p$ reaction in GeV region is significant and it has large branching ratio (88.8%) in the $\pi^+\pi^-\pi^0$ channel. The cross sections for this reaction have been calculated using the energy dependent reaction amplitude, i.e., $f_{\gamma p \to \omega p}(0)$, extracted from the latest $\omega$ meson photoproduction data. We use established procedure to calculate other factors, like width and propagator of the $\omega$ meson, so that our calculation can provide reliable cross section. The calculated results reproduce the measured $\pi^+\pi^-\pi^0$ invariant mass distribution spectra in the $\gamma p$ reaction.Comment: 13 pages, 5 figure

The role of rewards and demands in burnout among surgical nurses

Job rewards have both, an intrinsic and an extrinsic motivational potential, and lead to employees’ development as well as help them to achieve work goals. Rewards can balance job demands and protect from burnout. Due to changes on the labour market, new studies are needed. The aim of our study was to examine the role of demands and individual rewards (and their absence) in burnout among surgical nurses. Materials and Methods: The study was conducted in 2009 and 2010 with 263 nurses who worked in surgical wards and clinics in hospitals in Southern Poland. The hypotheses were tested by the use of measures of demands and rewards (Effort-Reward Imbalance Questionnaire by Siegrist) and burnout syndrome (Maslach Burnout Inventory). A cross-sectional, correlational study design was applied. Results: Nurses experienced the largest deficiencies in salary and prestige. Exhaustion was explained by stronger demands and lack of respect (large effect). Depersonalization was explained by stronger demands, lack of respect and greater job security (medium effect). Reduced personal achievement was explained by more demands and greater job security (small effect). Conclusions: Excessive demands and lack of esteem are key reasons for burnout among surgical nurses. Job security can increase burnout when too many resources are invested and career opportunities do not appear. These results may help to improve human resource management in the healthcare sector

Entrepreneurship in the United States

In this paper I examine changes in self-employment that have occurred since the early 1980s in the United States. It is a companion paper to a recent equivalent paper relating to the UK. Data on random samples of twenty million US workers are examined taken from the Basic Monthly files of the CPS (BMCPS), the 2000 Census and the 2005 American Community Survey (ACS). In contrast to the official definition of self-employment which simply counts the numbers of unincorporated self-employed, we also include the incorporated self-employed who are paid wages and salaries. The paper presents evidence on trends in self-employment for the US as a whole as well as in construction. Construction is particularly important given that it accounts for a fifth of all self-employment and self-employment rates are roughly double the national rates. It is also important given the existence of public sector procurement programs that primarily exist in construction that have the intended purpose of assisting firms owned by women and minorities. I document the fact that self-employment rates of white women and minorities in comparison to those of white males have increased in construction and elsewhere as have self-employment earnings. Despite this substantial disparities remain. I also find evidence of discrimination in the small business credit market. Firms owned by minorities in general and blacks in particular are much more likely to have their loans denied and pay higher interest than is the case for white males

Molecular marks for epigenetic identification of developmental and cancer stem cells

Epigenetic regulations of genes by reversible methylation of DNA (at the carbon-5 of cytosine) and numerous reversible modifications of histones play important roles in normal physiology and development, and epigenetic deregulations are associated with developmental disorders and various disease states, including cancer. Stem cells have the capacity to self-renew indefinitely. Similar to stem cells, some malignant cells have the capacity to divide indefinitely and are referred to as cancer stem cells. In recent times, direct correlation between epigenetic modifications and reprogramming of stem cell and cancer stem cell is emerging. Major discoveries were made with investigations on reprogramming gene products, also known as master regulators of totipotency and inducer of pluoripotency, namely, OCT4, NANOG, cMYC, SOX2, Klf4, and LIN28. The challenge to induce pluripotency is the insertion of four reprogramming genes (Oct4, Sox2, Klf4, and c-Myc) into the genome. There are always risks of silencing of these genes by epigenetic modifications in the host cells, particularly, when introduced through retroviral techniques. In this contribution, we will discuss some of the major discoveries on epigenetic modifications within the chromatin of various genes associated with cancer progression and cancer stem cells in comparison to normal development of stem cell. These modifications may be considered as molecular signatures for predicting disorders of development and for identifying disease states