Structure-properties relationships in triarylamine-based donor-acceptor molecules containing naphtyl groups as donor material for organic solar cells

The effects of replacing the phenyl rings of triphenylamine (TPA) by naphtyl groups are analysed on a series of push-pull molecules containing a 2-thienyl-dicyanovinyl acceptor group. UV-Vis absorption spectroscopy and cyclic voltammetry show that the introduction of one or two naphtyl groups in the structure has limited effects on the optical properties and energy levels of the molecule. On the other hand, the evaluation of the compounds as donor material in bi-layer solar cells with C60 as acceptor shows that the number and mode of linkage of the naphtyl groups exert a marked influence on the power conversion efficiency (PCE) of the cell. Two naphtyl groups lead to a decrease of PCE with respect to TPA, while a single naphtyl group produces opposite effects depending on the linking mode. Compared to TPA, an alpha-naphtyl group leads to a small decrease of PCE while in contrast a beta-naphtyl leads to a ~35% increase of PCE due to improved short-circuit current density (Jsc) and fill-factor. The determination of the hole-mobility of these two donors by the space-charge-limited current method shows that these effects are correlated with the higher hole-mobility of the β-naphtyl compound

Off gas preparation for vacuum pumps

Vacuum steel degassing plants generate off-gases that are hot, dangerous and dust laden.Therefore they must be cooled down, post-combusted or conveyed in a safe manner and filtered in order toprotect the vacuum pumps and the environment.A risk analysis is necessary for all kinds of vacuum plant regardless the pump system used.This analysis defines the hazard zones and the necessary means to avoid such hazards or a hazard compliantequipment to be installed. The handling of moisture and the protection against the associated corrosion effectsare a concern for the dust filters and the vacuum pumps.The dust load requires special means of erosion protection. The dust abatement and dust extraction fromthe various gears must be compliant with the dangers of impact by high speed particles, of dust ignition andof aqueous condensates. 50 % of the dust is in a range of 0,2 to 1,5 ?m and thus a challenge for filters thatcombine a high filtering efficiency with a low pressure drop.All necessary gears in the connection between vacuum pump and metallurgical reaction vessel, that areinstalled for post-combustion, gas cooling and dust abatement as well as suction duct with all its bows generatepressure losses that could only be compensated by an increased pump capacity. Since this is an importantinvestment and generates higher operation cost one is tempted to take means to reduce such losses. However,this might again require higher pump down capacities. A detailed study involving all parameters is thereforerecommended in order to evaluate the various measures to be taken

Development of a Molar Command Climate Survey

Studies examining our Military Forces' leadership state command climates form the foundation for the Army's culture. A climate should be measured and the results tied to outcomes. This study responds to Carr et al., (2003) and call for assessments that are more comprehensive and molar than measures currently used. As a test of the molar concept, this paper developed a new climate assessment and extends previous research by proposing a hybrid model linking antecedents of climate to three facets (or states) as moderators which have differential impacts upon a number of molar outcomes. INTRODUCTION General Edward C. Meyer, former Army Chief of Staff, (FM 22-100, 1999) wanted to ensure that the Army was prepared to go to war and to create a personally fulfilling climate. He added "Only by attaining the second could we assure ourselves of the first." A positive command climate is a prerequisite for leader and unit development A great leader builds organizational climates and obtains results. The flexible and adaptable leader, shaped by their climate, uses contingent leadership, and obtains results. Which is better? To answer this, we need to measure climate and tie the results to outcomes Background James and Jones (1974, 1979) developed a climate model. It described relationships to organizational outcomes like satisfaction. Bandwidth Climate is described both as a molar concept about broad outcomes like goals The climate model by Hypothesis 1: This modified climate model would reflect the relationships of climate to outcomes as illustrated in figure 2 and could thus, be used as a guide to developing a research tool and empirical test of this model. FIGURE 2 MODIFIED MODEL HYPOTHESIZING MODERATING RELATIONSHIPS AMONG CLIMATE DIMENSIONS, CLIMATE FACETS/STATES, AND OUTCOMES Climate Dimensions Climate Facets/States Outcomes METHOD The first official Army definition of command climate was published in December 1983 as Reference Book (RB) 22-5 (Lempke, 1988). This paper uses FM 22-100 (1999) command climate definition: "A state or condition existing from shared feelings, perceptions, attitudes, and beliefs among Soldiers about the formal and informal organizational policies, practices, and procedures regarding the day-to-day functioning of their unit." Murray, Survey Construction Most of the climate measures were too specific and measured particular climate types. To investigate the specificity and bandwidth of molar constructs, the LCCS was developed in an attempt to create a more concise and molar climate assessment tool and measure how climate relates to outcomes. Normal test development procedures were used. Items for each of the dimensions were written, focusing upon the FM 22-100 actions, behaviors, and values. The items were screened, reviewed, modified by focus groups at several military installations, and evaluated as climate indicators Thirty Captains who completed the survey were instructed to modify the items to either agree or disagree more strongly with the item's content. The final 150 items were administered to 380 enlisted active-duty Army Soldiers at five military installations. Eliminating records with random and irrelevant responses, resulted in 372 records. 57.7% classified themselves as White, 26.1% as Black, 11.4% as Hispanic, and 4.7% as Asian. 11.6% were female and 88.4% were male. Their ages ranged from 20 to 55 years. Their ranks ranged from PFC (Private First Class) to LTC (Lieutenant Colonel). The dimensions were classified into three facets; affective, cognitive, or instrumental as suggested by Journal of Organizational Psychology vol. 11(1) 2011 91 Hypothesis 2: The facet and states of the same name (cognitive facet and cognitive state, affective facet and affective state, and instrumental facet and instrumental state) will have similar beta-weights in their predictions. SPSS 12.0 was used to conduct a series of stepwise and hierarchical multiple regressions. Using the results from the stepwise procedure, 45 hierarchical regression analyses were conducted. This was a test of which dimensions predicted the facets, states, outcomes and to identify the important differential predictions. The detailed results of the 45 hierarchical regression analyses are not presented. RESULTS A PCA produced 39 components with eigenvalues greater than one and accounted for 69% of the variance (See table 2). These 39 components were used to derive dimension scales with adequate reliability (See A PCA was conducted on the 16 climate dimensions to see if it could approximate Ostroff's (1993) taxonomy. The results are presented in table 5. This PCA found three clusters of 4 to 6 scales with eigenvalues greater than one that accounted for about 78% of the variance. Facet scores were computed for each of the three climate facets by summing up the items identified by the PCA for each subscale. State scale scores were computed by summing up individual items that two raters agreed would relate to each of the specific states. The facet/state scale means, standard deviations, and alpha coefficients are reported in table 6. The coefficient alphas ranged from .91 to .98 for the facets and from .89 to .97 for the states

Brain-predicted age difference mediates the association between PROMIS sleep impairment, and self-reported pain measure in persons with knee pain

Knee pain, the most common cause of musculoskeletal pain (MSK), constitutes a severe public health burden. Its neurobiological causes, however, remain poorly understood. Among many possible causes, it has been proposed that sleep problems could lead to an increase in chronic pain symptomatology, which may be driven by central nervous system changes. In fact, we previously found that brain cortical thickness mediated the relationship between sleep qualities and pain severity in older adults with MSK. We also demonstrated a significant difference in a machine-learning-derived brain-aging biomarker between participants with low-and high-impact knee pain. Considering this, we examined whether brain aging was associated with self-reported sleep and pain measures, and whether brain aging mediated the relationship between sleep problems and knee pain. Exploratory Spearman and Pearson partial correlations, controlling for age, sex, race and study site, showed a significant association of brain aging with sleep related impairment and self-reported pain measures. Moreover, mediation analysis showed that brain aging significantly mediated the effect of sleep related impairment on clinical pain and physical symptoms. Our findings extend our prior work demonstrating advanced brain aging among individuals with chronic pain and the mediating role of brain-aging on the association between sleep and pain severity. Future longitudinal studies are needed to further understand whether the brain can be a therapeutic target to reverse the possible effect of sleep problems on chronic pain

Activation of Human Stearoyl-Coenzyme A Desaturase 1 Contributes to the Lipogenic Effect of PXR in HepG2 Cells

The pregnane X receptor (PXR) was previously known as a xenobiotic receptor. Several recent studies suggested that PXR also played an important role in lipid homeostasis but the underlying mechanism remains to be clearly defined. In this study, we found that rifampicin, an agonist of human PXR, induced lipid accumulation in HepG2 cells. Lipid analysis showed the total cholesterol level increased. However, the free cholesterol and triglyceride levels were not changed. Treatment of HepG2 cells with rifampicin induced the expression of the free fatty acid transporter CD36 and ABCG1, as well as several lipogenic enzymes, including stearoyl-CoA desaturase-1 (SCD1), long chain free fatty acid elongase (FAE), and lecithin-cholesterol acyltransferase (LCAT), while the expression of acyl:cholesterol acetyltransferase(ACAT1) was not affected. Moreover, in PXR over-expressing HepG2 cells (HepG2-PXR), the SCD1 expression was significantly higher than in HepG2-Vector cells, even in the absence of rifampicin. Down-regulation of PXR by shRNA abolished the rifampicin-induced SCD1 gene expression in HepG2 cells. Promoter analysis showed that the human SCD1 gene promoter is activated by PXR and a novel DR-7 type PXR response element (PXRE) response element was located at -338 bp of the SCD1 gene promoter. Taken together, these results indicated that PXR activation promoted lipid synthesis in HepG2 cells and SCD1 is a novel PXR target gene. © 2013 Zhang et al

LXR Deficiency Confers Increased Protection against Visceral Leishmania Infection in Mice

Leishmania spp. are protozoan single-cell parasites that are transmitted to humans by the bite of an infected sand fly, and can cause a wide spectrum of disease, ranging from self-healing skin lesions to potentially fatal systemic infections. Certain species of Leishmania that cause visceral (systemic) disease are a source of significant mortality worldwide. Here, we use a mouse model of visceral Leishmania infection to investigate the effect of a host gene called LXR. The LXRs have demonstrated important functions in both cholesterol regulation and inflammation. These processes, in turn, are closely related to lipid metabolism and the development of atherosclerosis. LXRs have also previously been shown to be involved in protection against other intracellular pathogens that infect macrophages, including certain bacteria. We demonstrate here that LXR is involved in susceptibility to Leishmania, as animals deficient in the LXR gene are much more resistant to infection with the parasite. We also demonstrate that macrophages lacking LXR kill parasites more readily, and make higher levels of nitric oxide (an antimicrobial mediator) and IL-1β (an inflammatory cytokine) in response to Leishmania infection. These results could have important implications in designing therapeutics against this deadly pathogen, as well as other intracellular microbial pathogens

The role of microRNA-155/liver X receptor pathway in experimental and idiopathic pulmonary fibrosis

Background: Idiopathic Pulmonary Fibrosis (IPF) is progressive and rapidly fatal. Improved understanding of pathogenesis is required to prosper novel therapeutics. Epigenetic changes contribute to IPF therefore microRNAs may reveal novel pathogenic pathways. Objectives: To determine the regulatory role of microRNA(miR)-155 in the pro-fibrotic function of murine lung macrophages and fibroblasts, IPF lung fibroblasts and its contribution to experimental pulmonary fibrosis. Methods: Bleomycin-induced lung fibrosis in wild-type and miR-155-/- mice was analyzed by histology, collagen and pro-fibrotic gene expression. Mechanisms were identified by in silico and molecular approaches; validated in mouse lung fibroblasts and macrophages, and in IPF lung fibroblasts, using loss-and-gain of function assays, and in vivo using specific inhibitors. Results: miR-155-/- mice developed exacerbated lung fibrosis, increased collagen deposition, collagen 1 and 3 mRNA expression, TGFβ production, and activation of alternatively-activated macrophages, contributed by deregulation of the microRNA-155 target gene the liver X receptor (LXR)α in lung fibroblasts and macrophages. Inhibition of LXRα in experimental lung fibrosis and in IPF lung fibroblasts reduced the exacerbated fibrotic response. Similarly, enforced expression of miR-155 reduced the pro-fibrotic phenotype of IPF and miR-155-/- fibroblasts. Conclusion: We describe herein a molecular pathway comprising miR-155 and its epigenetic LXRα target that when deregulated enables pathogenic pulmonary fibrosis. Manipulation of the miR-155/LXR pathway may have therapeutic potential for IPF

The farnesoid X receptor regulates transcription of 3 beta-hydroxysteroid dehydrogenase type 2 in human adrenal cells

Recent studies have shown that the adrenal cortex expresses high levels of farnesoid X receptor (FXR), but its function remains not known. Herein, using microarray technology, we tried to identify candidate FXR targeting genes in the adrenal glands, and showed that FXR regulates 3β-hydroxysteroid dehydrogenase type 2 (HSD3B2) expression in human adrenocortical cells. We further demonstrated that FXR stimulated HSD3B2 promoter activity and have defined the cis-element responsible for FXR regulation of HSD3B2 transcription. Transfection of H295R adrenocortical cells with FXR expression vector effectively increased FXR expression levels and additional treatment with chenodeoxycholic acid (CDCA) caused a 25-fold increase in the mRNA for organic solute transporter alpha (OSTα), a known FXR target gene. HSD3B2 mRNA levels also increased following CDCA treatment in a concentration-dependent manner. Cells transfected with a HSD3B2 promoter construct and FXR expression vector responded to CDCA with a 20-fold increase in reporter activity compared to control. Analysis of constructs containing sequential deletions of the HSD3B2 promoter suggested a putative regulatory element between -166 and -101. Mutation of an inverted repeat between -137 and -124 completely blocked CDCA/FXR induced reporter activity. Chromatin immunoprecipitation assays further confirmed the presence of a FXR response element in the HSD3B2 promoter. In view of the emerging role of FXR agonists as therapeutic treatment of diabetes and certain liver diseases, the effects of such agonists on other FXR expressing tissues should be considered. Our findings suggest that in human adrenal cells, FXR increases transcription and expression of HSD3B2. Alterations in this enzyme would influence the capacity of the adrenal gland to produce corticosteroids