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This study was conducted to determine the changes in total sugar, ascorbic acid, α- tocopherol and β-carotene content of fresh fruits of rosehip species during ripening, for three years. Fruits of selected genotypes belonging to Rosa dumalis, R.canina and R.villosa were used. Fruits were harvested in six different times based on hyphantium color change or flesh softening. The total sugars of R.dumalis, R.canina, and R.villosa fruits ranged between 11.22-16.68, 9.28-13.90, and 9.28-16.31%, respectively. Also, ascorbic acids varied between 767.1-1324.9, 168.7-481.5 and 241.2-574.2 mg 100 g-1, respectively; α-tocopherols ranged between 5.87-10.25, 5.29-10.04 and 2.74-11.65 mg 100 g-1, and β-carotenes varied between 0.18-2.03, 0.34-2.42 and 0.49-3.62 mg 100 g-1, respectively. Total sugar, ascorbic acid, α-tocopherol and β-carotene content linearly increased depending on ripening time. Relationships between total sugar and vitamins were significant. It was concluded that harvest should be delayed as much as possible in order to obtain fruits with high content of total sugar and the main components of vitamins. [ABSTRACT FROM AUTHOR]

INTRODUCTION Artificial sweeteners are frequently used to sweeten beverages and to decrease caloric intake by diabetic or nondiabetic adults in daily life. They were thought to be metabolically inactive, but [...], BACKGROUND/OBJECTIVE: Artificial sweeteners were thought to be metabolically inactive, but after demonstrating that the gustatory mechanism was also localized in the small intestine, suspicions about the metabolic effects of artificial sweeteners have emerged. The objective of this study was to determine the effect of artificial sweeteners (aspartame and sucralose) on blood glucose, insulin, c-peptide and glucagon-like peptide-1 (GLP-1) levels. SUBJECTS/METHODS: Eight newly diagnosed drug-naive type 2 diabetic patients (mean age 51.5 ± 9.2 years; F/M: 4/4) and eight healthy subjects (mean age 45.0 ± 4.1 years; F/M: 4/4) underwent 75 g oral glucose tolerance test (OGTT). During OGTT, glucose, insulin, c-peptide and GLP-1 were measured at 15-min intervals for 120 min. The OGTTs were performed at three settings on different days, where subjects were given 72 mg of aspartame and 24 mg of sucralose in 200 ml of water or 200 ml of water alone 15 min before OGTT in a single-blinded randomized order. RESULTS: In healthy subjects, the total area under the curve (AUC) of glucose was statistically significantly lower in the sucralose setting than in the water setting (P = 0.002). There was no difference between the aspartame setting and the water setting (P = 0.53). Total AUC of insulin and c-peptide was similar in aspartame, sucralose and water settings. Total AUC of GLP-1 was significantly higher in the sucralose setting than in the water setting (P = 0.04). Total AUC values of glucose, insulin, c-peptide and GLP-1 were not statistically different in three settings in type 2 diabetic patients. CONCLUSIONS: Sucralose enhances GLP-1 release and lowers blood glucose in the presence of carbohydrate in healthy subjects but not in newly diagnosed type 2 diabetic patients. European Journal of Clinical Nutrition (2015) 69, 162-166;doi:10.1038/ejcn.2014.208;published online 1 October 2014

Previous studies indicate that the dark conductivity in amorphous and microcrystalline silicon may increase or decrease with exposure to deionized water (DIW) or pure oxygen at 80°C but always decreases with light exposure. While the light-induced effect is linked to paramagnetic dangling bonds ([D.sup.o]), the origin of metastability in microcrystalline silicon remains unclear. In this study, we use steady-state photoconductivity (SSPC), dual-beam photoconductivity (DBP), and electron spin resonance (ESR), to study the behaviors under soaking in DIW and (or) pure oxygen at 80°C and light-exposure of amorphous (a-Si:H) and nanostructured (nc-Si:H) silicon samples deposited in a capacitively coupled plasma-enhanced chemical vapor deposition system. Powders from thick samples of low and high crystallinity (Xc) peeling off large substrates were collected in quartz tubes for ESR measurements. Dark conductivity decreases upon exposure to pure oxygen at 80°C for nc-Si:H but remains unchanged for a-Si:H. The ESR signal attributed to [D.sup.o] decreases with soaking in DIW for high and low crystallinity nc-Si:H but the effect is more significant for higher Xc. Changes inSSPC, DBP, and ESR are used to compare the degradation mechanisms because of [O.sub.2] exposure and light for amorphous and nanostructured silicon. PACS Nos.: 68.55.ag, 73.61.Jc, 73.63.Bd. Des etudes anterieures indiquent que la conductivite d'obscurite dans le silicium amorphe et microcristallin peut augmenter ou diminuer lorsqu'en contact avec de l'eau de-ionisee (DIW) ou de l'oxygene pur a 80°C, mais decroit toujours lorsqu'expose a la lumiere. Alors que l'effet induit par la lumiere est lie aux liens pendants paramagnetiques ([D.sup.o]), l'origine de la metastabilite du silicium microcristallin demeure opaque. Nous utilisons ici la photoconductivite stationnaire (SSPC), la photoconductivite modulee a deux faisceaux (DBP) et la resonance de spin electronique (ESR), afin d'etudier les comportements, lorsque plonges dans la DIW et (ou) l'oxygene pur a 80 °C et expose a la lumiere, d'echantillons de silicium amorphe (a-Si:H) et nano-structure (nc-Si:H), deposes dans un systeme a depot de vapeur traite par plasma avec couplage capacitif. Les poudres detachees des echantillons epais sur substrats, de haute et de basse cristallinite (Xc), sont collectees dans des tubes de quartz pour fins de mesures ESR. La conductivite en obscurite diminue sous exposition a l'oxygene pur a 80°C pour nc-Si:H, mais reste inchangee pour a-Si:H. Le signal ESR attribue a [D.sup.o] diminue lorsqu'on plonge un echantillon de nc-Si:H de haute et basse cristallinite dans la DIW, mais l'effet est plus important si Xc est plus grand. Nous utilisons les variations dans SSPC, DBP et ESR pour comparer les mecanismes de degradation dus a l'exposition a [O.sub.2] pur et a la lumiere dans des echantillons de silicium amorphe et nano-structure. [Traduit par la Redaction], Introduction Various structural phases of silicon have been tested in the production of efficient, stable, low-cost photovoltaic devices that compete well with nonrenewable fossil fuel sources of energy. Crystalline silicon [...]

Residential combined heat and power (CHP) systems using fuel cell technology can provide both electricity and heat and can substantially reduce the energy and environmental impact associated with residential applications. The energy, environmental, and economic characteristics of fuel cell CHP systems are investigated for single-family residential applications. Hourly energy use profiles for electricity and thermal energy are determined for typical residential applications. A mathematical model of a residential fuel cell based CHP system is developed. The CHP system incorporates a fuel cell system to supply electricity and thermal energy, a vapor compression heat pump to provide cooling in the summer and heating in the winter, and a thermal storage tank to help match the available thermal energy to the thermal energy needs. The performance of the system is evaluated for different climates. Results from the study include an evaluation of the major design parameters of the system, load duration curves, an evaluation of the effect of climate on energy use characteristics, an assessment of the reduction in emissions, and a comparison of the life cycle cost of the fuel cell based CHP system to the life cycle costs of conventional residential energy systems. The results suggest that the fuel cell CHP system provides substantial energy and environmental benefits but that the cost of the fuel cell sub-system must be reduced to roughly $500/kWe before the system can be economically justified. [DOI: 10.1115/1.1595112] Keywords: Fuel cell, PEMFC, cogeneration, heat, power, residential, energy

The influence of intrinsic carrier concentration on the compositional and temperature dependence of the bandgap of GaxIn1-xN is investigated in nominally undoped samples with Ga fractions of x = 0.019, 0.062, 0.324, 0.52, and 0.56. Hall Effect results show that the free carrier density has a very weak temperature dependence and increases about a factor of 4, when the Ga composition increases from x = 0.019 to 0.56. The photoluminescence (PL) peak energy has also weak temperature dependence shifting to higher energies and the PL line shape becomes increasingly asymmetrical and broadens with increasing Ga composition. The observed characteristics of the PL spectra are explained in terms of the transitions from free electron to localized tail states and the high electron density induced many-body effects. The bowing parameter of GaxIn1-xN is obtained from the raw PL data as 2.5 eV. However, when the high carrier density induced effects are taken into account, it increases by about 14% to 2.9 eV. Furthermore, the temperature dependence of the PL peak becomes more pronounced and follows the expected temperature dependence of the bandgap variation. [ABSTRACT FROM AUTHOR]