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The synthesis of Co-NPs and Mn-NPs by microwave-induced decomposition of the metal carbonyls Co-2(CO)(8) and Mn-2(CO)(10), respectively, yields smaller and better separated particles in the functionalized IL 1-methyl-3-(3-carboxyethyl)-imidazolium tetrafluoroborate [EmimCO(2)H][BF4] (1.6 +/- 0.3 nm and 4.3 +/- 1.0 nm, respectively) than in the non-functionalized IL 1-n-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4]. The particles are stable in the absence of capping ligands (surfactants) for more than six months although some variation in particle size could be observed by TEM.
A parameterization for the motion of ice-shelf fronts on a Cartesian grid in finite-difference land-ice models is presented. The scheme prevents artificial thinning of the ice shelf at its edge, which occurs due to the finite resolution of the model. The intuitive numerical implementation diminishes numerical dispersion at the ice front and enables the application of physical boundary conditions to improve the calculation of stress and velocity fields throughout the ice-sheet-shelf system. Numerical properties of this subgrid modification are assessed in the Potsdam Parallel Ice Sheet Model (PISM-PIK) for different geometries in one and two horizontal dimensions and are verified against an analytical solution in a flow-line setup.
This study was conducted to evaluate the effect of different wood vermicompost application rates on some soil physical and chemical properties as well as on growth parameters of a grass seed mixture (RSM 7.2.1) in tertiary sand contaminated with coal spoil. The experiment was carried out in a greenhouse over a period of 42 days. Soil was mixed with vermicompost at ratios of 0.0, 3.0, 12.5, and 25.0% and sown with the grass seed mixture. Soil samples and plant material were analyzed to determine the effect of different vermicompost application rates on the physical and chemical properties. Results revealed that the physical and chemical properties of the soil improved with increasing application rates of vermicompost. In addition, soil treated with vermicompost showed significant increases in fresh-and dry-matter yields of the grass, as well as enhanced uptake of nutrients by the grass. This indicated that treatment of contaminated soils with vermicompost may be beneficial for reclamation processes by facilitating revegetation of disturbed areas.
The selection of 'good' pictures has increasingly become a crucial factor when transmitting news to the recipients. Every day thousands of events are happening and millions of pictures are taken. By choosing photographs for newspapers and magazines, photographic editorial departments want to attract the recipients' attention, evoke emotions and get them to read their stories. But what exactly is a good picture that meets these expectations? Which criteria are decisive for selecting pictures and what effects of this selection can be measured on the recipients' side?
This article presents the results of a research project carried out at the University of Erfurt in 2008 and conducted in collaboration with the German weekly magazine stern. It deals with the selection and impact of press photography by introducing the concept 'photo news factors'. Applying the traditional news value theory to pictures, photo news factors are defined as selection criteria that, on the part of the communicator, decide whether the press photos are worth publishing. Furthermore, they are assumed to exert an influence on the intensity of attention that a picture arouses.
Background: Low birthweight is an independent risk factor of glucose intolerance and type 2 diabetes in later life. Genetically determined insulin resistance and subsequently impaired glucose uptake might explain both reduced fetal growth and elevated blood glucose. The glucose transporter 1 (GLUT!) plays an important role for fetal glucose uptake as well as for maternal-fetal glucose transfer, and it has been associated with insulin resistance in adults. The present study hypothesized that the common fetal GLUT1 XbaI polymorphism might reduce fetal insulin sensitivity and/or glucose supply in utero, thus affecting fetal blood glucose and fetal growth.
Methods: A genetic association study was conducted at the obstetrics department of the Charite University Hospital, Berlin, Germany. 119.1 white women were included after delivery, and all newborns were genotyped for the GLUT1 XbaI polymorphism. Total glycosylated hemoglobin was quantified, serving as a surrogate of glycemia during the last weeks of pregnancy.
Results: The analysis of this large population showed no significant differences in fetal glycosylated hemoglobin or birthweight for the different fetal GLUT1 XbaI genotypes. Only newborns carrying the mutated allele show the previously published inverse association between birthweight and glycosylated hemoglobin.
Conclusions: The results suggest that there is no prenatal effect of the fetal GLUT1 XbaI polymorphism on fetal insulin sensitivity, intrauterine fetal glucose supply or fetal growth. However, the polymorphism seems to modulate the inverse interaction between birthweight and fetal glycemia.
Background: Acute kidney injury (AKI) as well as chronic renal failure are associated with a huge mortality/morbidity. However, so far no drugs have been approved for the treatment of acute kidney failure and only a few for the treatment of chronic kidney disease (CKD). We analysed the effect of SLV 338, a neutral endopeptidase (NEP)/endothelin converting enzyme (ECE)-inhibitor in animal models of acute kidney failure as well as chronic renal failure.
Methods: Acute renal failure was induced in male Wistar rats by uninephrectomy and clamping of the remaining kidney for 55 minutes. SLV338 (total dose: 4.9 mg/kg) or vehicle was continuously infused for 2 hours (starting 20 minutes prior to clamping). Sham operated animals served as controls. Plasma creatinine was measured at baseline and day 2 and 8 after renal ischemia-reperfusion.
Hypertensive renal damage was induced in male Sprague Dawley rats by nitric oxide deficiency using L-NAME (50 mg/kg per day, added to drinking water for 4 weeks). One group was treated over the same time period with SLV338 (30 mg/kg per day, mixed with food). Systolic blood pressure was monitored weekly. At study end, urine and blood samples were collected and kidneys were harvested.
Results: Acute renal ischemia-reperfusion caused a 5-fold plasma creatinine elevation (day 2), which was significantly attenuated by more than 50 % in animals treated with SLV338 (p < 0.05). Renal failure was accompanied by a 67 % mortality in vehicle-treated rats, but only 20 % after SLV338 treatment (p = 0.03 compared to sham controls).
Chronic L-NAME administration caused hypertension, urinary albumin excretion, glomerulosclerosis, renal arterial remodelling, and renal interstitial fibrosis. Treatment with SLV338 did not significantly affect blood pressure, but abolished renal tissue damage (interstitial fibrosis, glomerulosclerosis, renal arterial remodelling (p < 0.05 versus L-NAME group in each case).
Conclusions: The dual ECE/NEP inhibitor SLV338 preserves kidney function and reduces mortality in severe acute ischemic renal failure. Moreover, combined ECE/NEP inhibition prevents hypertensive renal tissue damage in a blood pressure independent manner in L-NAME-treated rats.
Biomarkers for the prediction of mortality and morbidity in patients with renal replacement therapy
(2011)
The mortality of end-stage renal disease (ESRD) patients on dialysis remains high despite great improvement of dialysis technologies in the past decades.
These patients die due to infectious diseases (mainly sepsis), cardiovascular diseases such as myocardial infarction, heart failure, stroke, and, in particular, sudden cardiac death. End stage renal disease is a complex condition, where the failure of kidney function is accompanied by numerous metabolic changes affecting almost all organ systems of the human body. Many of the biomarker characteristics of the individually affected organ systems have been associated with adverse outcomes. These biomarkers are different in patients with ESRD compared to the general population in the prediction of morbidity and mortality. Biomarker research in this field should aim to identify patients at risk for the different disease entities.
Traditional biomarkers such as CRP, BNP, and troponins as well as new biomarkers such as fetuin, CD 154, and relaxin were analyzed in patients on dialysis. We will include observational as well as prospective clinical trials in this review. Furthermore, we will also discuss proteomics biomarker studies. The article assess the potential diagnostic value of different biomarkers in daily clinical practice as well as their usefulness for clinical drug development in end stage renal disease patients.
Greenland ice sheet model parameters constrained using simulations of the Eemian Interglacial
(2011)
Using a new approach to force an ice sheet model, we performed an ensemble of simulations of the Greenland Ice Sheet evolution during the last two glacial cycles, with emphasis on the Eemian Interglacial. This ensemble was generated by perturbing four key parameters in the coupled regional climate-ice sheet model and by introducing additional uncertainty in the prescribed "background" climate change. The sensitivity of the surface melt model to climate change was determined to be the dominant driver of ice sheet instability, as reflected by simulated ice sheet loss during the Eemian Interglacial period. To eliminate unrealistic parameter combinations, constraints from present-day and paleo information were applied. The constraints include (i) the diagnosed present-day surface mass balance partition between surface melting and ice discharge at the margin, (ii) the modeled present-day elevation at GRIP; and (iii) the modeled elevation reduction at GRIP during the Eemian. Using these three constraints, a total of 360 simulations with 90 different model realizations were filtered down to 46 simulations and 20 model realizations considered valid. The paleo constraint eliminated more sensitive melt parameter values, in agreement with the surface mass balance partition assumption. The constrained simulations resulted in a range of Eemian ice loss of 0.4-4.4m sea level equivalent, with a more likely range of about 3.7-4.4m sea level if the GRIP delta O-18 isotope record can be considered an accurate proxy for the precipitation-weighted annual mean temperatures.
Acyclic diene metathesis a versatile tool for the construction of defined polymer architectures
(2011)
Two decades have passed since the metathesis polymerisation of alpha,omega-dienes was successfully demonstrated by the group of Wagener and the term acyclic diene metathesis (ADMET) polymerisation was coined. Since then, the advances of metathesis chemistry have allowed to expand the scope of this versatile polymerisation reaction that nowadays finds applications in different fields, such as polymer, material, or medicinal chemistry. This critical review provides an insight into the historical aspects of ADMET and a detailed overview of the work done to date applying this versatile polymerisation reaction (221 references).