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We present results from the characterization and optimization of Skipper charge-coupled devices (CCDs) for use in a focal plane prototype for the Southern Astrophysical Research Integral Field Spectrograph (SIFS). We tested eight Skipper CCDs and selected six for SIFS based on performance results. The Skipper CCDs are 6k × 1k, 15 μm pixels, thick, fully depleted, p-channel devices that have been thinned to ∼250 μm, backside processed, and treated with an anti-reflective coating. We demonstrate a single-sample readout noise of <4.3 e−rms pixel−1in all amplifiers. We optimize the readout sequence timing to achieve a readout noise of 0.5 e−rms pixel−1after 74 non-destructive measurements, which can be accomplished in a region covering 5% of the detector area in a readout time of <4 minutes. We demonstrate single-photon-counting in all 24 amplifiers (four amplifiers per detector) with a readnoise of σN∼ 0.18 e−rms pixel−1after Nsamp= 400 samples, and we constrain the degree of nonlinearity to be ≲1% at low signal levels (0 e−to 50 e−). Clock-induced charge (CIC) remains an important issue when the Skipper CCD is configured to provide a large full-well capacity. We achieve a CIC rate of <1.45 × 10−3e−pixel−1frame−1for a full-well capacity of ∼900 e−, which increases to a CIC rate of ∼3 e−pixel−1frame−1for full-well capacities ∼40,000–65,000 e−. We also perform conventional CCD characterization measurements such as charge transfer inefficiency (3.44 × 10−7on average), dark current (∼2 × 10−4e−pixel−1s−1), photon transfer curves, cosmetic defects (<0.45% “bad” pixels), and charge diffusion (point-spread function < 7.5 μm) to verify that these properties are consistent with expectations from conventional p-channel CCDs used for astronomy. Furthermore, we provide the first measurements of the brighter-fatter effect and absolute quantum efficiency (≳80% between 450 and 980 nm; ≳90% between 600 and 900 nm) using Skipper CCDs.

Objectives:To compare the effects of a palatable cafeteria diet on serum parameters and neuroinflammatory markers of young and aged female Wistar rats.Methods:Three-month-old (young) and 18-month-old (aged) female Wistar rats had access to a cafeteria diet (Caf-Young, Caf-Aged) or a standard chow diet (Std-Young, Std-Aged).Results:The Caf-Young group showed a higher food consumption, weight gain, visceral fat depot, serum insulin and leptin levels, and the insulin resistance index (HOMA-IR) than the Std-Young group. The Caf-Aged group exhibited an increase in interleukin-1 levels in the cerebral cortex and hippocampus. The number of GFAP-positive cells did not differ between the groups, but there was a diet effect in the cerebral cortex and an age effect in the hippocampus. Phospho-tau expression did not differ between the groups.Discussion:The 3- and 18-month-old rats responded differently to a cafeteria diet. Insulin and leptin levels are elevated in young animals fed a cafeteria diet, whereas aged animals are prone to neuroinflammation (indicated by an increase in interleukin-1β levels). A combination of hypercaloric diet and senescence have detrimental effects on the inflammatory response in the brain, which may predispose to neurological diseases.

We prepared a W/WO3/TiO2bicomposite photoanode by simple electrochemical anodization of W foil, followed by cathodic electrodeposition of TiO2and annealing at 450°C for 30min. This photoanode shows good photoactivity under irradiation with UV and visible light. In optimized conditions, it promotes complete photoelectrocatalytic oxidation of 3.33×10-5molL-1basic red 51 solution (which is used in hair dye) at 0.1molL-1Na2SO4, pH 2.0, under a current density of 1.25mAcm-2and ultraviolet and visible radiation–total organic carbon removal is 94 and 88%, respectively. This effect paves the way for the sustainable solar-assisted remediation of water bodies contaminated with organic components of hair dyes.

The effects of anoxic exposure and the post‐anoxia aerobic recovery period on carbohydrate metabolism in the central nervous system (CNS) of the land snail Megalobulimus oblongus, an anoxia‐tolerant land gastropod, were studied. The snails were exposed to anoxia for periods of 1.5, 3, 6, 12, 18, or 24 hr. In order to study the post‐anoxia recovery phase, snails exposed to a 3‐hr period of anoxia were returned to aerobic conditions for 1.5, 3, 6, or 15 hr. Glycogen and glucose concentrations in the CNS, hemolymph glucose concentration, and glycogen phosphorylase (active form, GPa) activity in the CNS were analyzed. Anoxia does not significantly affect the concentration of CNS glucose but induces hyperglycemia and a reduction of CNS GPa activity. The glycogen concentration was decreased at 12 hr of anoxia; however, by 18 and 24 hr in anoxia, the glycogen content was not significantly different from basal control values. During the post‐anoxia period, the reduction in GPa activity and the increased hemolymph glucose concentration induced by anoxia returned to control values. These results suggest that the CNS of M. oblongus may use hemolymph glucose to fulfill the metabolic demands during anoxia. However, the hypothesis of tissue metabolic arrest cannot be excluded. J. Exp. Zool. 301A:968–978, 2004. © 2004 Wiley‐Liss, Inc.

The indiscriminate use of hair dyes has attracted great deal of attention due to its toxicological and mutagenic aspects demonstrated by some of these substances. Thus, the effluent from beauty salons and domestic sewages if not properly treated can reach water treatment plants and water sources, enhancing human health and environmental protection concern. This work explores the application of photoelectrocatalytic process on Basic Brown 16 and Basic Blue 99 degradation as model of basic hair dyes pollutants. W/WO3electrode was used as photoanode under optimized conditions of 0.10 mol L–1Na2SO4as electrolytic solution, pH 2.0, under 1.25 mA cm–2of controlled current density application and visible light irradiation. The process leads to complete color removal, and up to 59 % and 44 % mineralization of Basic Brown 16 and Basic Blue 99, respectively. The use of W/WO3photoanodes under visible irradiation could assist on development of wastewater treatment technology.