243 research outputs found
Mixing of the vibrational angular momentum components of multiply degenerate vibronic states of benzene by vibrational l-type resonance
The rotationally resolved spectra of the 6011002 and 6011602 vibronic transitions of benzene at low rotational temperat reported and analyzed in detail. Deperturbed spectroscopic constants for the 61102 and 61162 states are reported which reproduce the observed line positions to within experimental accuracy. The splitting of 17.9 cm−1 between the two subbands of the 6011002 transition and of 6.2 cm−1 for the 6011602 transition is found to be due to vibrational l-type resonances with matrix element 8.91 and 2.65 cm−1, respectively. These large resonances cause strong distortions of the rotational structure and mix the vibrational angular momentum substates ν6minus-or-plus sign + 2ν100 and ν6± + 2ν10±2 nearly completely and the substates ν6minus-or-plus sign + 2ν160 and ν6± + 2ν16minus-or-plus sign2 substantially. The importance of the mixing for the intramolecular vibrational redistribution (IVR) and the decay behaviour of S1 benzene is discussed
Investigations on the Effects of Different Calcium Supply Exceeding the Requirements on Mineral Serum Concentrations and Bone Metabolism in Young Warmblood Stallions
Since mineral supplements for horses commonly contain macro minerals, although the requirement for such is usually covered by roughage-based diets, the aim of this study was to investigate the effects of different dietary calcium levels on mineral serum concentrations and bone metabolism. The trial was conducted in 30 young warmblood stallions (2–3 years) that were divided into two groups for a five-month feeding trial. The groups were fed a hay- and oat-based diet and were either supplied with high (Ca-High) or moderate (Ca-Moderate) calcium excess. While in Ca-High calcium supply was about 2–2.5-fold of the requirement, in Ca-Moderate calcium requirements were slightly surpassed (1.5–1.6-fold). In order to monitor the effects of the different calcium supply, blood samples were taken during the trial and analysed for levels of macro and trace elements as well as concentrations of two bone markers. In Ca-Moderate a trend towards higher phosphorus serum levels compared to Ca-High was observed which was significant at the end of the trial (p = 0.0002). Furthermore, results showed no influence of the diet on bone markers. Results support the idea that forage-based rations for horses do not necessarily have to be supplemented with macro minerals but with trace elements
Development of Cryogenic Filter Wheels for the HERSCHEL Photodetector Array Camera & Spectrometer (PACS)
This paper describes the two PACS Filter Wheels that are direct-drive rotational mechanisms operated at a temperature below 5K inside the PACS focal plane unit of the Herschel Satellite. The purpose of the mechanisms is to switch between filters. The rotation axis is pivoted to the support structure via a slightly preloaded pair of ball bearings and driven by a Cryotorquer. Position sensing is realized by a pair of Hall effect sensors. Powerless positioning at the filter positions is achieved by a magnetic ratchet system. The key technologies are the Cryotorquer design and the magnetic ratchet design in the low temperature range. Furthermore, we will report on lessons learned during the development and qualification of the mechanism and the paint
Omega-3 polyunsaturated fatty acids and bronchial inflammation in grass pollen allergy after allergen challenge
SummaryRatioAsthma is a major public health problem, with bronchial inflammation as the therapeutic target. The role of dietary fish oil derived polyunsaturated fatty acids (PUFAs) in allergic inflammation is controversial. Most asthmatics suffer from mild disease and non-pharmacologic interventions are attractive. This study investigates the anti-inflammatory potential of nutritional PUFAs in an experimentally induced bronchial inflammation.MethodsWe examined 38 grass pollen allergic asthmatics and 19 controls. History of dietary PUFA intake was compared with levels of PUFAs in erythrocyte membranes, and stratified according to low (25th quartile; Q25) and high (75th quartile; Q75) ratios of omega-3 (n-3) to omega-6 (n-6) PUFAs as a surrogate for anti-inflammatory (Q75) or proinflammatory (Q25) effects. Bronchial inflammation was simulated with one-step inhalation of grass pollen. Bronchial response (exhaled nitric monoxide, eNO as surrogate for inflammation, decrease of FEV1) was correlated with levels of PUFAs in erythrocyte membranes.ResultsRatios of n-3/n-6 PUFA were significantly lower in asthmatics than in healthy controls. Levels of eNO were significantly higher in Q25 asthmatics than in Q75 asthmatics (p = 0.040). There was a trend of higher bronchial hyperreactivity in Q25 asthmatics (median PD20 0.27 vs. 0.14; n.s.), induced by specific bronchial challenge with grass pollen (FEV1 decrease 16.7 vs. 23.1%; n.s.).ConclusionWhen stratifying for erythrocyte membrane PUFA content as a surrogate for alimentary intake, we found mild effects on bronchial allergic inflammation. Future intervention studies with pharmacological PUFA doses appear suitable to clarify dietary PUFA role as an adjunctive intervention to the established treatment of asthma.ClinicalTrials.gov No. NCT00519740
A hospital-wide evaluation of delirium prevalence and outcomes in acute care patients : a cohort study
Background: Delirium is a well-known complication in cardiac surgery and intensive care unit (ICU) patients. However, in many other settings its prevalence and clinical consequences are understudied. The aims of this study were: (1) To assess delirium prevalence in a large, diverse cohort of acute care patients classified as either at risk or not at risk for delirium; (2) To compare these two groups according to defined indicators; and (3) To compare delirious with non-delirious patients regarding hospital mortality, ICU and hospital length of stay, nursing hours and cost per case.
Methods: This cohort study was performed in a Swiss university hospital following implementation of a delirium management guideline. After excluding patients aged < 18 years or with a length of stay (LOS) < 1 day, 29′278 patients hospitalized in the study hospital in 2014 were included.
Delirium period prevalence was calculated based on a Delirium Observation Scale (DOS) score ≥ 3 and / or Intensive Care Delirium Screening Checklist (ICDSC) scores ≥4.
Results: Of 10′906 patients admitted, DOS / ICDSC scores indicated delirium in 28.4%. Delirium was most prevalent (36.2–40.5%) in cardiac surgery, neurosurgery, trauma, radiotherapy and neurology patients. It was also common in geriatrics, internal medicine, visceral surgery, reconstructive plastic surgery and cranio-maxillo-facial surgery patients (prevalence 21.6–28.6%). In the unadjusted and adjusted models, delirious patients had a significantly higher risk of inpatient mortality, stayed significantly longer in the ICU and hospital, needed significantly more nursing hours and generated significantly higher costs per case. For the seven most common ICD-10 diagnoses, each diagnostic group’s delirious patients had worse outcomes compared to those with no delirium.
Conclusions: The results indicate a high number of patients at risk for delirium, with high delirium prevalence across all patient groups. Delirious patients showed significantly worse clinical outcomes and generated higher costs. Subgroup analyses highlighted striking variations in delirium period-prevalence across patient groups. Due to the high prevalence of delirium in patients treated in care centers for radiotherapy, visceral surgery, reconstructive plastic surgery, cranio-maxillofacial surgery and oral surgery, it is recommended to expand the current focus of delirium management to these patient groups
Vascular smooth muscle BK channels limit ouabain‐induced vasocontraction: dual role of the Na/K‐ATPase as a hub for Src‐kinase and the Na/Ca‐exchanger
Large-conductance, calcium-activated potassium channels (BK channels) and the Na/K-ATPase are expressed universally in vascular smooth muscle. The Na/K-ATPase may act via changes in the intracellular Ca2+ concentration mediated by the Na/Ca exchanger (NCX) and via Src kinase. Both pathways are known to regulate BK channels. Whether BK channels functionally interact in vascular smooth muscle cells with the Na/K-ATPase remains to be elucidated. Thus, this study addressed the hypothesis that BK channels limit ouabain-induced vasocontraction. Rat mesenteric arteries were studied using isometric myography, FURA-2 fluorimetry and proximity ligation assay. The BK channel blocker iberiotoxin potentiated methoxamine-induced contractions. The cardiotonic steroid, ouabain (10−5 M), induced a contractile effect of IBTX at basal tension prior to methoxamine administration and enhanced the pro-contractile effect of IBTX on methoxamine-induced contractions. These facilitating effects of ouabain were prevented by the inhibition of either NCX or Src kinase. Furthermore, inhibition of NCX or Src kinase reduced the BK channel-mediated negative feedback regulation of arterial contraction. The effects of NCX and Src kinase inhibition were independent of each other. Co-localization of the Na/K-ATPase and the BK channel was evident. Our data suggest that BK channels limit ouabain-induced vasocontraction by a dual mechanism involving the NCX and Src kinase signaling. The data propose that the NCX and the Src kinase pathways, mediating the ouabain-induced activation of the BK channel, act in an independent manner
Improved hole extraction selectivity of polymer solar cells by combining PEDOT:PSS with WO 3
As the device performance and stability of polymer solar cells strongly depend on the interfacial charge extraction layers, the hole transport layer (HTL) properties are crucial. Furthermore, unfavorable interactions with the electrode or the photoactive layer should be screened and prevented. Organic solar cells of conventional architecture by varying the HTL material and layer stack systematically between PEDOT:PSS and a sol–gel‐derived tungsten oxide (WO 3 ) are investigated. The impact of various HTLs in the solar cells is investigated by optical and electrical characterization. Interestingly, a triple‐layer WO 3 /PEDOT:PSS/WO 3 configuration results in the best device performance specifically compared with the use of pristine WO 3 and pristine PEDOT:PSS hole extraction layers. The triple layer also shows an increased reproducibility in the lifetime, which, combined with the improvement in the efficiency, can be the keys for expectable revenue
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