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Abstract Global irradiance spectra vary with location, different viewing angles and times of day, depending on the fraction of direct and diffuse irradiance. Owing to big differences in spectral responses, PV module technologies might therefore show a differing behaviour with varying orientation and tilt angles. The purpose of this work is to verify the thesis, that thin film modules are – due to their spectral response – more suitable for horizontal orientation than crystalline. Diffuse irradiation (except from circumsolar radiation) can be captured best by a horizontal surface and consists to a greater fraction of short wavelengths than direct irradiation. At the same time thin film modules primarily absorb photons of short wavelengths and could therefore be better suited for horizontal application. Based on the semi-empirical spectral model Sedes2 and quantum efficiency data, a model has been developed to analyse differences in optimum orientation of several PV module technologies. In a first step, hourly global irradiance spectra are generated from a 1 year dataset of hourly climate data derived from long-term averages by the Meteonorm database for two sites in different climes. Based on this, average photocurrent densities are computed for each technology and for a matrix of different orientation and tilt angles using quantum efficiency data. Normalised to their maximum, the photocurrent densities are compared between the technologies. The results we obtained show, that for each site the maximum relative photocurrent densities are located at about the same orientation for all technologies, i.e. the optimum orientation is the same. At horizontal orientation, thin film modules show a slightly higher value of normalised average photocurrent densities than monocrystalline modules. Yet, for a whole year this advantage lies below 1% for both sites.

AbstractAlcoholism is a major health problem in Western countries, yet relatively little is known about the mechanisms by which chronic alcohol abuse causes the pathologic changes associated with the disease. It is likely that chronic alcoholism affects a number of signaling cascades and transcription factors, which in turn result in distinct gene expression patterns. These patterns are difficult to detect by traditional experiments measuring a few mRNAs at a time, but are well suited to microarray analyses. We used cDNA microarrays to analyze expression of approximately 10 000 genes in the frontal and motor cortices of three groups of chronic alcoholic and matched control cases. A functional hierarchy was devised for classification of brain genes and the resulting groups were compared based on differential expression. Comparison of gene expression patterns in these brain regions revealed a selective reprogramming of gene expression in distinct functional groups. The most pronounced differences were found in myelin‐related genes and genes involved in protein trafficking. Significant changes in the expression of known alcohol‐responsive genes, and genes involved in calcium, cAMP, and thyroid signaling pathways were also identified. These results suggest that multiple pathways may be important for neuropathology and altered neuronal function observed in alcoholism.

In the North-Central USA, switchgrass to be used as a biomass feedstock typically will be harvested in the autumn. The accumulated area harvested over the harvest season (defined here as the harvest progression) will influence the size of the machinery fleet and seasonal labor required to complete the majority of the harvest before the first lasting snow. A harvest progression model was developed that uses drying rate, mower and baler productivity, and weather conditions as major inputs. Ten years of weather data (2005–2014) from Wisconsin, Iowa, and Nebraska (WI, IA, NE) were used. Harvest progression was modeled for four harvest systems involving conventional and intensive conditioning both swathed and tedded (CC, IC, CCT, and ICT, respectively) and two dates at which harvest began (1 September and after a killing frost). To reduce risk of exposing crop to prolonged periods of inclement weather, mowers were idled when more than 80 ha were cut but not yet baled. For all sites, the harvest start date and the mower idled constraint had greater impact on harvest progression than the type of harvest system. Harvest progression was greatest when mowing started on 1 September and continued whenever weather permitted (i.e., no mower idled constraint). Compared to the harvest system used today (CC), using the IC system resulted in more area harvested with less crop exposed to rain after cutting and considerably less area left to be baled in the spring. Starting harvest on 1 September, using intensive conditioning, and not idling the mowers might be considered the system that best balances the desire for rapid harvest progression, small equipment fleet size, low-capital expenditures, and maximum labor utilization.

The limited availability of a high-performance catholyte has hindered the development of aqueous organic redox flow batteries (AORFB) for large-scale energy storage. Here we report a symmetry-breaking design of iron complexes with 2,2′-bipyridine-4,4′-dicarboxylic (Dcbpy) acid and cyanide ligands. By introducing two ligands to the metal centre, the complex compounds (M4[FeII(Dcbpy)2(CN)2], M = Na, K) exhibited up to a 4.2 times higher solubility (1.22 M) than that of M4[FeII(Dcbpy)3] and a 50% increase in potential compared with that of ferrocyanide. The AORFBs with 0.1 M Na4[FeII(Dcbpy)2(CN)2] as the catholyte were demonstrated for 6,000 cycles with a capacity fading rate of 0.00158% per cycle (0.217% per day). Even at a concentration near the solubility limit (1 M Na4[FeII(Dcbpy)2(CN)2]), the flow battery exhibited a capacity fading rate of 0.008% per cycle (0.25% per day) in the first 400 cycles. The AORFB cell with a nearly 1:1 catholyte:anolyte electron ratio achieved a cell voltage of 1.2 V and an energy density of 12.5 Wh l–1. The development of aqueous organic redox flow batteries suffers from the limited availability of high-performance catholytes. Here the authors design a metal organic complex catholyte material with a tunable redox potential, which offers promise for high-energy long-lasting flow batteries.

Neurons in the rat hippocampal formation (the dentate gyrus and the hippocampus) are born over a protracted period, from gestational day (G) 15 into adulthood. Dentate gyral neurons born prenatally are generated from the ventricular zone, whereas those born postnatally are derived from a secondary proliferative zone, the intrahilar zone. In contrast, hippocampal pyramidal neurons are generated only prenatally from the ventricular zone. In the neocortex, ethanol depresses the proliferation of cells in the ventricular zone and stimulates the proliferation of cells in the secondary proliferative zone. The present study tests the hypotheses that prenatal treatment with ethanol has a different effect on the generation of dentate gyral neurons than does postnatal ethanol treatment, and that these differences are determined by the timing of the ethanol exposure relative to the period and site of neuronal generation.Rats were treated with ethanol between G6 and G21 or between postnatal day (P) 4 and P12. They were given an injection of [3H]thymidine on G15, G18, G21, P6, P9, or P12. Rats were killed on P30–P35. The tissue was processed by standard autoradiographic methods and assessed using rigorous stereological procedures. The total number of neurons and the density of radiolabeled neurons in both the dentate gyrus and the CA1 region of the hippocampus were determined.Prenatal ethanol treatment decreased the total number of neurons in the CA1 segment of the hippocampus and had little impact on neuronal number in the dentate gyrus. Likewise, the number of hippocampal and dentate gyral neurons generated daily was significantly lower in ethanol‐treated rats than in controls. Postnatal treatment to ethanol, however, significantly increased the total number of dentate gyral neurons and the density of neurons generated postnatally. These postnatal changes depended on the blood ethanol concentration (BEC). At moderate BECs, the total number of neurons in the dentate gyrus and the number of neurons generated was increased. At high BECs, however, neuronal number and neuronal generation were decreased. Postnatal ethanol treatment had no effect on the number of (total or radiolabeled) CA1 neurons.Thus, pre‐ and postnatal exposure to ethanol have opposite effects both on the number of neurons in the dentate gyrus and on the generation of neurons. These paradoxical effects likely result from three causes: the differential effects of ethanol on the two proliferative zones, the critical period of neuronal development, and the potentially opposite effects of moderate and high BEC.

Abstract DeCART multi-group cross section library generation procedure based on the KAERI library generation system was improved using the new alternative procedures based on the Monte Carlo slowing down calculations. In the new alternative procedures, the resonance integral tables were generated by solving the slowing down equation with continuous energy Monte Carlo calculations and the new procedures for the library generation were incorporated for the additional improvements. Most of fission product and actinide nuclides are processed as resonant nuclides to reduce the errors which are resulted from the approximate treatment of their resonance cross sections, and the one-group effective FPYs (Fission Product Yield) which are calculated by fission reaction rates are incorporated for improving the accuracy of the burnup calculations. Using the new procedure and ENDF/B-VII.1 evaluated nuclear data library, new DeCART cross section libraries are generated and they are tested for various benchmark calculations for pin-cell, FA, and core depletion problem against the McCARD reference solutions. The results confirmed that the new generated libraries can be used in the PWR SMR (Small Modular Reactor) core design.

Background: In the brain, nitric oxide (NO) produced by neuronal nitric oxide synthase (nNOS) has a role in synaptic plasticity. Recent evidence suggests the role of NO in a variety of effects produced by alcohol in the central nervous system. The current study investigated the role of the nNOS gene in the development of behavioral sensitization to ethanol in adolescent and adult mice.Methods: Adolescent and adult wild type (WT; B6;129SF2) and nNOS knockout (KO; B6;129S4‐Nos1) mice of both sexes received saline or ethanol (1.5 g/kg; intraperitoneally) for 5 consecutive days, and locomotor activity was recorded daily. The locomotor response to challenge ethanol and saline injections was investigated at various time points following withdrawal from ethanol.Results: Adolescent WT but not nNOS KO mice developed a long‐lasting sensitized response to ethanol as well as context‐dependent hyperlocomotion (in response to saline) from adolescence through adulthood; sex‐dependent differences were not observed. Compared to adolescent WT mice, adult WT males developed a short‐term sensitized response to ethanol and context‐dependent hyperlocomotion; adult WT females showed only short‐term context‐dependent hyperlocomotion. Adult nNOS KO males (like their adolescent counterparts) did not develop behavioral sensitization; no significant differences between adult nNOS KO and WT females were observed. Blood ethanol concentrations did not show genotype‐ or sex‐dependent differences.Conclusions: (1) The nNOS gene is required for the development of behavioral sensitization to ethanol in adolescent male and female mice. (2) Adolescent exposure to ethanol results in long‐lasting behavioral sensitization through adulthood, while adult exposure to ethanol results in a shorter behavioral sensitization. (3) Sex‐dependent differences are observed when ethanol exposure begins in adulthood but not in adolescence. (4) Ethanol‐induced behavioral sensitization in adulthood is nNOS‐dependent in males but not in females. Taken together, results suggest genotype‐, ontogeny‐, and sex‐dependent differences in the development of behavioral sensitization to ethanol.

AbstractCarbon nanotubes (CNTs) have been used for various bioelectrochemical applications, presumably for substantial improvement in performance. However, often only moderate results observed, with many governing factors have been considered and suggested yet without much systematic evaluation and verification. In this study, CNT‐supported glucose oxidase (CNT–GOx) was examined in the presence of 1,4‐benzoquinone (BQ). The intrinsic Michaelis parameters of the reaction catalyzed by CNT–GOx were found very close to those of native GOx. However, the Nafion entrapment of CNT–GOx for an electrode resulted in a much lower activity due to the limited availability of the embedded enzyme. Interestingly, kinetic studies revealed that the biofuel cell employing such an enzyme electrode only generated a power density equivalent to <40% of the reaction capability of the enzyme on electrode. It appeared to us that factors such as electron and proton transfer resistances can be more overwhelming than the heterogeneous reaction kinetics in limiting the power generation of such biofuel cells. Biotechnol. Bioeng. 2009; 104: 1068–1074. © 2009 Wiley Periodicals, Inc.