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Rationale, aims, and objectives: During general anaesthesia, body core temperature is influenced by several factors that are either anaesthesia‐related (type and duration of anaesthesia and fluid management), surgery‐related (type of surgery and extent of the surgical procedure), or patient‐related (age, gender, body weight, and preoperative body core temperature). Interestingly, data concerning body mass index (BMI) and its influence on patients' temperature are sparse. The aim of this study was to evaluate the impact of BMI on body core temperature under general anaesthesia. Methods: A single centre, prospective, observational study was conducted at a university hospital. Two cohorts (lower limb surgery and abdominal surgery) were evaluated. Patients were treated according to actual German guidelines for the prevention of hypothermia. Temperature was measured sublingually prior to anaesthesia and during the first 60 minutes of anaesthesia. Each cohort was divided in three subgroups (BMI < 24 kg m−2, BMI 25‐34.9 kg m−2, and BMI > 35 kg m−2) according to body weight. Results: A total of 206 patients were evaluated. One hundred four underwent lower limb surgery; 102 underwent abdominal surgery. After induction of anaesthesia, temperature dropped in all subgroups, but this decline was more pronounced in patients with lower BMI. Significant differences concerning temperature changes were observed in abdominal surgery between low and high BMI groups. After 60 minutes of anaesthesia, group‐dependent temperature differences had levelled out, and relevant differences compared with preoperative temperatures could no longer be observed in any of the groups. Conclusion: Current guidelines provide effective protection against perioperative hypothermia. In the current study, this was true for obese as well as normal weight patients. [ABSTRACT FROM AUTHOR]

Abstract: Fe3N and Fe3C nanocomposites have a wide range of applications thanks to their ceramic nature, magnetic properties, conductivity and catalytic activity, just to cite some. In many fields optimal performances are ensured by crystallinity, homogeneity and hierarchical organization. In the present paper, crystalline, magnetic and well‐defined nanofibres of iron nitride and iron carbide/carbon nanocomposite with tunable composition and size were prepared via electrospinning. The starting polymeric material was directly electrospun into fibres and then calcined, leading to a highly homogeneous final product of nanoparticles along the fibres (both outside and inside). A mechanistic study was undertaken and here discussed. The magnetic properties of the as‐prepared nanofibres were also studied. The as‐prepared final fibre mat composite material can serve as active catalyst, for example, in oxygen reduction reaction (where nanofibres outperformed mere nanoparticles), it can serve as functional support for classical catalytic processes or, thanks to its magnetic properties, can be applied in magnetic‐field assisted separation or as magneto‐active membranes. [ABSTRACT FROM AUTHOR]

Problem The endothelial glycocalyx ( EGX) plays an important role in vascular integrity. Recently, increased levels of EGX components were detected in the circulating blood of healthy pregnant women and were related to the increased tendency to edema formation during gestation. However, the EGX has not yet been systematically studied in non-pregnant women during ovulatory cycles. Method of study Serum levels of EGX components syndecan-1, heparan sulfate, and hyaluronan in healthy women (n = 16) at 3 phases of the ovulatory cycle (early follicular phase, at ovulation, and mid-luteal phase) were compared with a control group of healthy men (n = 10). Using immunofluorescence microscopy in cultured human umbilical vein endothelial cells, the effects of progesterone and estrogen on the EGX were measured. Results Syndecan-1 increased from 11.1 ± 2.4 ng/ mL at ovulation to 12.6 ± 2.3 ng/ mL in mid-luteal phase ( P = .031) and of heparan sulfate from 663 ± 35 ng/ mL to 782 ± 55 ng/ mL ( P = .011). In contrast to estrogen, there was a detrimental effect of progesterone on the EGX in HUVECs. Conclusion The relationship between the natural menstrual cycle and the EGX as an indicator of vascular permeability may provide a new explanation for premenstrual edema in healthy women. This may be an attendant phenomenon of a regular physiological process, the hormonal downregulation of the vascular barrier during pregnancy. [ABSTRACT FROM AUTHOR]

Doping of Li/MgO with additional metal ions is suggested leading to an improved system with respect to the catalytic performance and stability when used for oxidative coupling of methane. We used Gd and Fe as dopants and characterized the resulting materials, showing that Fe seems to be completely and Gd partly incorporated into the MgO lattice. The catalytic performance is improved in most cases, but all materials still suffer from severe deactivation. A loss of Li is observed when being used under reaction conditions, but this Li loss is retarded for Fe-Li/MgO as compared to undoped Li/MgO. [ABSTRACT FROM AUTHOR]

Yield predictions are performed to predict the solar resource, the performance and the energy production over the expected lifetime of a photovoltaic (PV) system. In this study, we compare yield predictions and monitored data for 26 PV power plants located in southern Germany and Spain. The monitoring data include in-plane irradiance for comparison with the estimated solar resource and energy yield for comparison with predicted performance. The results show that because of increased irradiance in recent years ('global brightening') the yield predictions systematically underestimate the energy yield of PV systems by about 5%. Because common irradiance databases and averaging times were used for the yield predictions analysed in this paper, it is concluded that yield predictions for areas where the global brightening effect occurred in general underestimated the energy yield by the same magnitude. Using recent satellite-derived irradiance time series avoids this underestimation. The observed performance ratio of the analysed systems decreases by 0.5%/year in average with a relatively high spread between individual systems. This decrease is a main factor for the combined uncertainty of yield predictions. It is attributed to non-reversible degradation of PV cells or modules and to reversible effects, like soiling. Based on the results of the validation, the combined uncertainty of state of the art yield predictions using recent solar irradiance data is estimated to about 8%. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, we investigate the performance ratio (PR) of about 100 German photovoltaic system installations. Monitored PR is found to be systematically lower by ~2-4% when calculated with irradiation data obtained by pyranometers (henceforth denoted as PRPyr) as compared with irradiation amounts measured by reference cells (denoted as PRSi). Annual PRSi for the ~100 systems is found to be between ~70% and ~90% for the year 2010, with a median PR of ~84%. Next, simulations were performed to determine loss mechanisms of the top 10 performing systems, revealing a number of these loss mechanisms may still allow for some optimization. Despite the fact that we do not see such values from our monitoring data base up to now, we believe PRSi values above 90% are realistic even today, using today's commercially available components, and should be expected more frequently in the future. This contribution may help in deepening our knowledge on both energy loss mechanisms and efficiency limits on the system level and standardization processes of system-related aspects. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Perioperative fluid management and fluid shifting have been main topics of debate in the recent years. Liberal fluid application is still a common practice and fluid overload believed to be a minor problem. Recent studies, however, have shown that liberal fluid management facilitates fluid shifts into the interstitial space especially in the context of major abdominal surgery. Consequently, the integrity of the vascular barrier is a rediscovered target of research. The endothelial glycocalyx, which covers the endothelial cells on the luminal side of every healthy vessel, plays a key role concerning the barrier properties of healthy blood vessels. Together with bound plasma proteins the glycocalyx forms the endothelial surface layer with a thickness of about 1 µm. With these packed proteins, this layer has its own colloid osmotic force. Damage of the endothelial glycocalyx can lead to protein extravasation and tissue edema. The endothelial glycocalyx is also important concerning leukocyte and platelet adhesion and shear-stressed nitric oxide-release and therefore, very probably, with regard to the pathophysiology of diseases like sepsis and ischemia/reperfusion injury. The purpose of this review is to elucidate the physiological and functional impact of the endothelial glycocalyx in transvascular fluid shifts. [ABSTRACT FROM AUTHOR]