Biological Markers of Auditory Gap Detection in Young, Middle-Aged, and Older Adults

The capability of processing rapid fluctuations in the temporal envelope of sound declines with age and this contributes to older adults' difficulties in understanding speech. Although, changes in central auditory processing during aging have been proposed as cause for communication deficits, an open question remains which stage of processing is mostly affected by age related changes. We investigated auditory temporal resolution in young, middle-aged, and older listeners with neuromagnetic evoked responses to gap stimuli with different leading marker and gap durations. Signal components specific for processing the physical details of sound stimuli as well as the auditory objects as a whole were derived from the evoked activity and served as biological markers for temporal processing at different cortical levels. Early oscillatory 40-Hz responses were elicited by the onsets of leading and lagging markers and indicated central registration of the gap with similar amplitude in all three age groups. High-gamma responses were predominantly related to the duration of no-gap stimuli or to the duration of gaps when present, and decreased in amplitude and phase locking with increasing age. Correspondingly, low-frequency activity around 200 ms and later was reduced in middle aged and older participants. High-gamma band, and long-latency low-frequency responses were interpreted as reflecting higher order processes related to the grouping of sound items into auditory objects and updating of memory for these objects. The observed effects indicate that age-related changes in auditory acuity have more to do with higher-order brain functions than previously thought

Estudio teórico y experimental de la respuesta a cortante en juntas secas de puentes de dovelas

En este artículo se presentan los estudios realizados en el proyecto de investigación PB98-0927 financiado por el Ministerio de Educación y Cultura en el periodo 1999 a 2002. En este proyecto se ha realizado una extensa campaña experimental, así como un profundo estudio teórico, del comportamiento en ELU, frente a solicitaciones combinadas de cortante y flexión, de juntas secas en puentes construidos mediante dovelas prefabricadas.Peer ReviewedPostprint (published version

Determining the accuracy of gestation feed drops

An experiment was conducted to determine the accuracy of three different gestation feed drops. Each drop was tested at three different angles (90, 75, 60°) from the feed line. Feed was collected and weighed at feeder settings of 2, 4, 6, 8, and 10 lb for the Econo- Drop and Accu-Drop feed dispensers. Samples were taken at 2, 4, 6, and 8 lb for the Ultra- Drop feed dispenser due to a smaller storage capacity for feed with this feed drop. There were five replications (five drops of each type) at each feed setting. There was a drop type by angle interaction (P<0.01) for the feed dispenser settings versus the actual pounds of feed dropped. At angles of 90 or 60 degrees, the Accu-Drop and the Ultra-Drop feed dispensers more (P<0.10) accurately dropped the correct amount of feed at the respective feeder settings. The amount of feed dropped at each dispenser setting was influenced more by angle to the feed line with the Econo-Drop than with the Accu-Drop or Ultra- Drop feed dispensers. This study demonstrated that the Accu-Drop and the Ultra-Drop feed dispensers are more accurate than the Econo-Drop feed dispenser. Therefore, producers should consider the additional feed cost over the lifetime of the feed drops and not rely solely on initial price

Effect of restricted feed intake on finishing pigs weighing between 150 and 250 lb fed twice or six times daily

Two 42-d trials and two 28-d trials were conducted to evaluate the effects of restricted feed intake and feeding frequency (2 or 6 times daily) on the performance of pigs weighing between 150 to 250 lb (initially 148 lb in Exp. 1; 155 lb in Exp. 2; 156 lb in Exp. 3; and 156 lb in Exp. 4). In all experiments, pigs were housed in 6 × 10 ft pens with half-solid concrete and half-slatted flooring and with one nipple waterer. Pigs were fed a corn-soybean meal-based diet formulated to 1.15% TID lysine and 1,491 kcal of ME/lb. In Exp. 1 to 3, energy and lysine were supplied to pigs to target an average growth rate of 1.75 lb/d based on NRC (1998) values. In Exp. 4, the diet was supplied to pigs to target growth rates of 1.75 lb/d (low feed intake) or 2.1 lb/d (high feed intake) based on NRC (1998) values to determine if the amount of energy above maintenance and feeding frequency has an effect on performance. Pigs were fed by dropping similar daily amounts of feed, either 2 (0700 and 1400) or 6 times (3 meals within 2 h at AM and PM feedings) per day, by an Accu-Drop Feed Dispenser® on the solid concrete flooring. In Exp. 1 and 2, increasing the feeding frequency of pigs fed a restricted diet from 2 to 6 times per day improved (P0.05) in performance between pigs fed 2 times per day when feed was dropped from the feed drop or by the modified method. In Exp. 4, increasing the feeding frequency from 2 to 6 feeding periods improved (P<0.01) ADG and F/G for pigs fed a low level of feed intake and tended to increase (P<0.06) ADG and improve (P<0.05) F/G for pigs fed a high level of feed intake. In conclusion, these studies indicate that increasing the frequency of feeding from 2 to 6 times a day improves pig performance compared with feeding 2 times per day

Determining the total sulfur amino acid to lysine requirement of the lactating sow

A total of 163 sows were used in a study to determine the requirement for total sulfur amino acids (TSAA), relative to lysine, during lactation. All experimental diets were cornsoybean meal-based and formulated to contain 0.88% true ileal digestible (TID) lysine (0.97% total lysine). The experimental diets contained 0.37% L-lysine HCl, with other crystalline amino acids added to ensure that TSAA was first limiting. The dietary TID TSAA rates were formulated to 0.44, 0.48, 0.53, 0.57, and 0.62%, corresponding to 50, 55, 60, 65, and 70% of lysine, respectively. Sows farrowed in six farrowing groups, and were randomly allotted to the dietary treatments on the basis of parity. Over the entire lactation period, there were no differences (P>0.14) in ADFI, weight loss, backfat loss, or plasma urea nitrogen among sows fed increasing TSAA:Lys ratios. Increasing TSAA, relative to lysine, had no effect (P>0.25) on litter weaning weight or preweaning mortality. In summary, there were no differences in litter performance with increasing TID TSAA:Lys ratio. These results suggest that the requirement for TID TSAA is no more than 50% of lysine. Additional research is needed to confirm this relatively low TSAA requirement, and that the relatively high feed (and amino acid) intake of sows, coupled with possible tissue breakdown as a source of TSAA, did not decrease the dietary requirement

Determining the accuracy of gestation feed drops

An experiment was conducted to determine the accuracy of three different gestation feed drops. Each drop was tested at three different angles (90, 75, 60°) from the feed line. Feed was collected and weighed at feeder settings of 2, 4, 6, 8, and 10 lb for the Econo- Drop and Accu-Drop feed dispensers. Samples were taken at 2, 4, 6, and 8 lb for the Ultra- Drop feed dispenser due to a smaller storage capacity for feed with this feed drop. There were five replications (five drops of each type) at each feed setting. There was a drop type by angle interaction (P\u3c0.01) for the feed dispenser settings versus the actual pounds of feed dropped. At angles of 90 or 60 degrees, the Accu-Drop and the Ultra-Drop feed dispensers more (P\u3c0.10) accurately dropped the correct amount of feed at the respective feeder settings. The amount of feed dropped at each dispenser setting was influenced more by angle to the feed line with the Econo-Drop than with the Accu-Drop or Ultra- Drop feed dispensers. This study demonstrated that the Accu-Drop and the Ultra-Drop feed dispensers are more accurate than the Econo-Drop feed dispenser. Therefore, producers should consider the additional feed cost over the lifetime of the feed drops and not rely solely on initial price.; Swine Day, 2006, Kansas State University, Manhattan, KS, 200

Stochastic bias of colour-selected BAO tracers by joint clustering-weak lensing analysis

The baryon acoustic oscillation (BAO) feature in the two-point correlation function of galaxies supplies a standard ruler to probe the expansion history of the Universe. We study here several galaxy selection schemes, aiming at building an emission-line galaxy (ELG) sample in the redshift range $0.6<z<1.7$, that would be suitable for future BAO studies, providing a highly biased galaxy sample. We analyse the angular galaxy clustering of galaxy selections at the redshifts 0.5, 0.7, 0.8, 1 and 1.2 and we combine this analysis with a halo occupation distribution (HOD) model to derive the properties of the haloes these galaxies inhabit, in particular the galaxy bias on large scales. We also perform a weak lensing analysis (aperture statistics) to extract the galaxy bias and the cross-correlation coefficient and compare to the HOD prediction. We apply this analysis on a data set composed of the photometry of the deep co-addition on Sloan Digital Sky Survey (SDSS) Stripe 82 (225 deg$^2$), of Canda-France-Hawai Telescope/Stripe 82 deep \emph{i}-band weak lensing survey and of the {\it Wide-Field Infrared Survey Explorer}infrared photometric band W1. The analysis on the SDSS-III/constant mass galaxies selection at $z=0.5$ is in agreement with previous studies on the tracer, moreover we measure its cross-correlation coefficient $r=1.16\pm0.35$. For the higher redshift bins, we confirm the trends that the brightest galaxy populations selected are strongly biased ($b>1.5$), but we are limited by current data sets depth to derive precise values of the galaxy bias. A survey using such tracers of the mass field will guarantee a high significance detection of the BAO.Comment: 17 pages, 15 figures, submitted to MNRA

Investigation into the effects of feeding schedule on body condition, aggressiveness, and reproductive failure in group housed sows

A total of 208 sows and 288 gilts (PIC Line C29) were used to determine the influence of feeding frequency (2 versus 6 times per day) in gestation on performance and welfare measurements. The experiment was conducted on a commercial sow farm in northeast Kansas that typically housed gestating sows and gilts in pens. Treatments consisted of feeding similar amounts of feed to each sow or gilt over 2 (07:00 and 15:30) or 6 meals per day (07:00, 07:30, 08:00, 15:30, 16:00, and 16:30 hours). There were 8 sows or 12 gilts in each pen. Gilts and sows were moved to pens after breeding. In gestating sows, there were no differences (P\u3e0.10) between treatments in ADG, backfat change, or variation in body weight. There was a trend (P\u3c0.08) for sows fed twice a day to farrow more total number born, but number born alive or other measures of reproductive performance were not different (P\u3e0.10) among treatments. Sows fed 6 times a day had increased vocalization during the morning (P\u3c0.07) and afternoon (P\u3c0.01) feeding periods, compared with sows fed twice a day, but sows fed twice a day had more skin (P\u3c0.01) and vulva (P\u3c0.04) lesions, as well as a small, but significant, increase in feet/leg (P\u3c0.01) and hoof (P\u3c0.02) problems. In this commercial facility, the standard management protocol required moving gilts to a different gestation facility. On d 42, two pens of gilts with similar breeding dates and treatment were combined and moved to another facility with larger pens until farrowing. From d 0 to 42, gilts fed 6 times a day had greater ADG (P\u3c0.07) and d-42 backfat (P\u3c0.09). After movement to the larger groups from d 42 to farrowing, ADG was similar (P \u3e 0.10) for gilts fed 2 or 6 times per day. Gilts fed twice a day had less weight variation at both d 42 (P\u3c0.04) and at farrowing (P\u3c0.10). In gilts, there were no differences (P\u3e0.10) for reproductive performance, skin and vulva lesions, and leg/feet and hoof scores. In conclusion, there were few growth, farrowing, or aggression differences among gilts fed either 2 or 6 times per day. This suggests that either feeding method is suitable for group-housed gilts. Among sows, different feeding frequency resulted in few growth or farrowing-performance differences. Feeding 6 times per day did result in a small, but significant, reduction in skin and vulva lesions and structural-problem scores, while increasing vocalization. Increasing the feeding frequency from 2 to 6 times per day does not seem to have a dramatic negative or positive impact on performance or welfare of group-housed gilts and sows.; Swine Day, 2006, Kansas State University, Manhattan, KS, 200

The Long-Term Impact of Physical and Emotional Trauma: The Station Nightclub Fire

Background: Survivors of physical and emotional trauma experience enduring occupational, psychological and quality of life impairments. Examining survivors from a large fire provides a unique opportunity to distinguish the impact of physical and emotional trauma on long-term outcomes. The objective is to detail the multi-dimensional long-term effects of a large fire on its survivor population and assess differences in outcomes between survivors with and without physical injury. Methods and Findings: This is a survey-based cross-sectional study of survivors of The Station fire on February 20, 2003. The relationships between functional outcomes and physical injury were evaluated with multivariate regression models adjusted for pre-injury characteristics and post-injury outcomes. Outcome measures include quality of life (Burn Specific Health Scale–Brief), employment (time off work), post-traumatic stress symptoms (Impact of Event Scale–Revised) and depression symptoms (Beck Depression Inventory). 104 fire survivors completed the survey; 47% experienced a burn injury. There was a 42% to 72% response rate range. Although depression and quality of life were associated with burn injury in univariate analyses (p<0.05), adjusted analyses showed no significant relationship between burn injury and these outcomes (p = 0.91; p = .51). Post-traumatic stress symptoms were not associated with burn injury in the univariate (p = 0.13) or adjusted analyses (p = 0.79). Time off work was the only outcome in which physical injury remained significant in the multivariate analysis (p = 0.03). Conclusions: Survivors of this large fire experienced significant life disruption, including occupational, psychological and quality of life sequelae. The findings suggest that quality of life, depression and post-traumatic stress outcomes are related to emotional trauma, not physical injury. However, physical injury is correlated with employment outcomes. The long-term impact of this traumatic event underscores the importance of longitudinal and mental health care for trauma survivors, with attention to those with and without physical injuries