Methamphetamine impairs sexual motivation but not sexual performance in male Japanese quail.

The present study investigated the effects of chronic pre-exposure to methamphetamine on sexual motivation and performance in male Japanese quail. Quail were pre-exposed to methamphetamine (1.0 or 3.0 mg/kg ip) or saline (ip) once daily for 10 days and locomotor activity was measured. After a 10 day washout period, sexual motivation was measured in a straight-arm runway with visual access to a female at one end. Three to 5 hr after sexual motivation tests, males were allowed to copulate with a receptive female quail and copulatory behavior was assessed. Tests were conducted once per day for 10 days. Results showed that males pre-exposed to methamphetamine had decreased locomotor activity compared to saline controls. Males pre-exposed to METH later ran slower toward a female in the runway and spent less time near her. In contrast, methamphetamine pre-exposed males showed similar copulatory behavior as saline pre-exposed males. The findings suggest that chronic pre-exposure to methamphetamine may impair sexual motivation but not sexual performance. The findings are discussed from a comparative perspective and with regard to their clinical relevance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Displays for hand-held portable electronic products

Abstract— The hand-held electronic-product field includes most telecommunication, palm computing, and navigation products, making this a large market for smaller displays (typically from 1 to 4 in. on the diagonal). Historically, this market has demanded displays with low power and cost, rather than high image quality, as evidenced by the historical dominance of monochrome TN and STN displays. However, within these constraints there is a strong trend toward larger displays capable of higher information content, including a migration toward low-power color solutions.     

Full sternotomy through a minimally invasive incision: a cardiac surgeon''s true comfort zone

The increasing risk of perioperative stroke after coronary artery bypass grafting can in part be attributed to the increased incidence of carotid stenosis with increasing patient age. The efficacy of carotid endarterectomy has been demonstrated for both symptomatic and asymptomatic patients. Combined operations yield acceptable mortality and stroke risks, provide good freedom from late events, and cost less than staged operations.     

Field measurement and wind tunnel simulation of hurricane wind loads on a single family dwelling

During landfall of Hurricane Ivan on the Florida ’panhandle’ in 2004, pressure time-history data were recorded on multiple pressure sensors installed on the roofs of six single-family homes. An analysis approach was developed to determine the peak negative, mean, peak positive, and standard deviation of pressure coefficients for these datasets. This paper presents a comparison of the full scale pressure coefficients from one of these homes, which experienced sustained hurricane force winds, with the results of wind tunnel experiments on a 1:50 scale model of that home. It was determined that the wind tunnel and full-scale mean and rms pressure coefficients matched very closely at almost every monitored location on the roof, while the peak negative pressure coefficients in the wind tunnel study generally underestimated the full-scale values, consistent with observations from previous full-scale/wind tunnel comparative studies. Field-measured hurricane wind loads may prove useful for evaluating existing wind load provisions. However, recommendations in that regard are premature without the analyses of multiple homes in multiple storms, performed by more than one wind tunnel facility. Future work will focus on building such a joint study.     

Silage review: Recent advances and future technologies for baled silages

Although the concept of ensiling large-round or large-square bales dates back to the late 1970s, many refinements have been made to both equipment and management since that time, resulting in much greater acceptance by small or mid-sized dairy or beef producers. This silage preservation technique is attractive to producers for several reasons, but the primary advantage is a reduced risk of weather damage to valuable forage crops compared with preservation as dry hay. Most core principles for making high-quality precision-chopped silages also apply to baled silages; among these, establishing and subsequently maintaining anaerobiosis are priorities. For baled silages, these priorities are critical, in part because recommended moisture concentrations (45 to 55%) are drier, and particle length is much longer. These factors act to restrict the rate and extent of silage fermentation, often resulting in less production of desirable fermentation acids and a greater (less acidic) final pH. Within this context, preservation of baled silages can be improved by applying polyethylene (PE) film wraps promptly, using an appropriate number of PE film layers (6 to 8), selecting a storage site free of sharp objects or other debris, and by monitoring wrapped bales closely for evidence of puncture, particularly by birds or vermin. Under certain conditions, such as those in which the bale moisture of highly buffered forages exceeds the recommended range, the heterogeneous nature of baled silages coupled with a restricted rate and extent of fermentation may increase susceptibility to clostridial activity compared with precision-chopped forages ensiled at comparable moisture concentrations. To date, research evaluating inoculants or other additives designed to improve the fermentation of challenging forages or aerobic stability has been limited, but should not be discontinued. Development of PE film embedded with an oxygen-limiting barrier has yielded positive results in some trials; however, most differences between these novel formulations and reputable commercial PE film have been related to decreases in yeast and mold counts at the surface layer. Related assessments of fermentation or nutritive value determined on a whole-bale basis have been less conclusive. Baled silages can be produced successfully by adhering to straightforward management principles; as such, this form of silage production is likely to remain popular for the foreseeable future.     

An efficient reduction route for the production of Pd–Pt nanoparticles anchored on graphene nanosheets for use as durable oxygen reduction electrocatalysts

Pt and Pd–Pt nanoparticles were anchored on reduced graphene oxide (RGO) with the aid of poly(diallyldimethylammonium chloride) (PDDA), where Pt and Pd ions were first attached to PDDA-functionalized graphene oxide sheets and the encased metal ions and graphene oxide were then reduced simultaneously by ethylene glycol. As supported by transmission electron microscopy, metal nanoparticles, of small particle size even at a high metal loading, were chemically attached to PDDA–RGO. X-ray diffraction indicates that the as-prepared Pd–Pt nanoparticles have a single-phase fcc structure and are principally alloys of Pd and Pt. Among the RGO-supported Pt and Pd–Pt catalysts, Pt nanoparticles anchored on PDDA–RGO exhibit the highest activity for the oxygen reduction reaction (ORR), and the ORR activity of the Pd–Pt alloy electrocatalysts increases with Pt content. All the catalysts demonstrate an enhanced ORR durability when PDDA is present; strongly suggesting that PDDA plays a crucial role in the dispersion and stabilization of the metal nanoparticles on RGO. The ORR activities of the Pd–Pt catalysts remain enhanced even after accelerated durability testing. The formation of a Pt-rich shell, as confirmed by X-ray photoelectron spectroscopy and CO stripping voltammetry, may account for the increased activity.     

Influence of corn silage hybrid type on lactation performance by Holstein dairy cows

The primary objective of this study was to determine lactation performance by dairy cows fed nutridense (ND), dual-purpose (DP), or brown midrib (BM) corn silage hybrids at the same concentration in the diets. A secondary objective was to determine lactation performance by dairy cows fed NutriDense corn silage at a higher concentration in the diet. One hundred twenty-eight Holstein and Holstein × Jersey cows (105 ± 38 d in milk) were stratified by breed and parity and randomly assigned to 16 pens of 8 cows each. Pens were then randomly assigned to 1 of 4 treatments. Three treatment total mixed rations (TMR; DP40, BM40, and ND40) contained 40% of dry matter (DM) from the respective corn silage hybrid and 20% of DM from alfalfa silage. The fourth treatment TMR had ND corn silage as the sole forage at 65% of DM (ND65). A 2-wk covariate adjustment period preceded the treatment period, with all pens receiving a TMR with equal proportions of DP40, BM40, and ND40. Following the covariate period, cows were fed their assigned treatment diets for 11 wk. nutridense corn silage had greater starch and lower neutral detergent fiber (NDF) content than DP or BM, resulting in ND40 having greater energy content (73.2% of total digestible nutrients, TDN) than DP40 or BM40 (71.9 and 71.4% TDN, respectively). Cows fed BM40 had greater milk yield than DP40, whereas ND40 tended to have greater milk yield and had greater protein and lactose yields compared with DP40. No differences in intake, component-corrected milk yields, or feed efficiency were detected between DP40, BM40, and ND40. Milk yield differences may be due to increased starch intake for ND40 and increased digestible NDF intake for BM40 compared with DP40. Intake and milk yield and composition were similar for ND40 compared with BM40, possibly due to counteracting effects of higher starch intake for ND40 and higher digestible NDF intake for BM40. Feeding ND65 reduced intake, and thus milk and component yields, compared with ND40 due to either increased ruminal starch digestibility or increased rumen fill for ND65. Nutridense corn silage was a viable alternative to both DP and BM at 40% of diet DM; however, lactation performance was reduced when nutridense corn silage was fed at 65% of DM.     

Effects of overstocking at the feedbunk on the growth performance and sorting characteristics of a forage-based diet offered for ad libitum intake to replacement Holstein dairy heifers

Various forms of overcrowding are common in heifer-rearing operations. Our objectives for this study were to evaluate the effects of overstocking at the feedbunk (100, 133, 160, or 200% of capacity) on the growth performance, feedbunk sorting behaviors, and hygiene of 128 gravid Holstein heifers (475 ± 55.3 kg) consuming an alfalfa haylage and corn silage diet diluted with processed wheat straw at an inclusion rate of 25.2% (DM basis). In this study, heifers were overstocked only at the feedbunk, and not with respect to available freestalls or pen area. Heifers were blocked by weight, and subsequently assigned to 1 of 16 identical research pens. A total mixed ration was distributed at 1000 h daily for 91 d via a drive-through feed alley, with heifers allowed access to the feedbunk through head-locking feeding gates. Mean weights for the 4 blocks (32 heifers/block) were 406 ± 14.9, 453 ± 15.3, 493 ± 17.6, and 548 ± 21.9 kg. Generally, nutrient intakes were not affected by stocking rate at the feedbunk; mean intakes of dry matter, neutral detergent fiber, and total digestible nutrients across all feedbunk stocking rates were 10.63, 5.19, and 6.29 kg/d, respectively. Overall, the effects of competition at the feedbunk on heifer growth performance were minor, with a collective average daily gain of 1.02 kg/d across all treatments. Only trends for linear increases in total weight gain and BCS were observed with overstocking at the feedbunk. Collectively, overstocked rates also exhibited a trend for better feed-to-gain ratio than pens stocked at 100% of feedbunk capacity (10.3 vs. 11.0 kg:kg). We observed solid evidence that heifers collectively sorted against large (>19 mm) particles, and also exhibited preference for short (>1.18 and <8 mm) and fine (<1.18 mm) feed particles; however, these responses were not affected by feedbunk stocking rate. Additionally, heifers sorted against neutral detergent fiber as the concentration of neutral detergent fiber remaining in the feedbunk increased during the 24-h period following feeding; conversely, they preferred crude protein, as indicated by a decreasing concentration of this nutrient over time. Heifer hygiene was not affected by competition at the feedbunk. Under the experimental conditions established for this trial, overstocking at the feedbunk did not affect heifer growth performance, but it should not be practiced blindly without attention to other critical components of animal welfare.     

Stimulus control of copulatory behavior in sexually naive male Japanese quail (Coturnix japonica): Effects of test context and stimulus movement.

Sexually experienced male quail (Coturnix japonica) are more likely to engage in copulatory behavior than sexually naive ones. These experiments suggest that sexual experience in a particular place may facilitate later copulatory responding because of increased familiarity with the contextual cues of the environment. Male quail in Exp 1 did not copulate reliably with taxidermic models of females in a novel context, even though some of the subjects were allowed to copulate with female quail in their home cages. In contrast, sexually naive males in Exps 2 and 3 copulated vigorously with taxidermic models of females in a familiar context. In Exp 4, sexually naive males tested in an unfamiliar context were more likely to copulate with a moving than with a static model. The stimulus control of copulatory behavior in sexually naive male quail was similar to that in sexually experienced ones but only in familiar contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)