Timing,frequency, and duration of incubation recesses in dabbling ducks

Nest attendance is an important determinant of avian reproductive success, and identifying factors that influence the frequency and duration of incubation recesses furthers our understanding of how incubating birds balance their needs with those of their offspring. We characterized the frequency and timing (start time, end time, and duration) of incubation recesses for mallard (Anas platyrhynchos) and gadwall (Mareca strepera) hens breeding in Suisun Marsh, California, USA, and examined the influences of day of year, ambient temperature at the nest, incubation day, and clutch size on recess frequency and timing using linear mixed models. Mallard, on average, took more recesses per day (1.69 ± 0.80, mean ± standard deviation) than did gadwall (1.39 ± 0.69), and 45% of mallard nest‐days were characterized by two recesses, while only 27% of gadwall nest‐days were characterized by two recesses. Mallard morning recesses started at 06:14 ± 02:46 and lasted 106.11 ± 2.01 min, whereas mallard afternoon recesses started at 16:39 ± 02:11 and lasted 155.39 ± 1.99 min. Gadwall morning recesses started at 06:30 ± 02:46 and lasted 91.28 ± 2.32 min, and gadwall afternoon recesses started at 16:31 ± 01:57 and lasted 192.69 ± 1.89 min. Mallard and gadwall started recesses earlier in the day with increasing ambient temperature, but later in the day as the season progressed. Recess duration decreased as the season progressed and as clutch size increased, and increased with ambient temperature at the nest. The impending darkness of sunset appeared to be a strong cue for ending a recess and returning to the nest, because hens returned to their nests earlier than expected when recesses were expected to end after sunset. Within hens, the timing of incubation recesses was repeatable across incubation days and was most repeatable for mallard afternoon recesses and on days in which hens took only one recess. Hens were most likely to be away from nests between 04:00 and 07:00 and between 16:00 and 19:00; therefore, investigators should search for nests between 07:00 and 16:00. Our analyses identified important factors influencing incubation recess timing in dabbling ducks and have important implications for nest monitoring programs.     

HLA genetic profile of Mapuche (Araucanian) Amerindians from Chile

Amerindian Mapuche (Araucanians) are now living in Chile and Argentina at both sides of Andean Mountains. They are anthropologically and genetically different from southernmost South America Patagonian Amerindians. Most of the HLA alleles found in our Mapuche sample are frequent or very frequent in North and South America Amerindians: (1) Class I: A*02:01, A*03:01, A*68:01, B*39:09, B*51:01, (2) Class II: DRB1*03:01, DRB1*04:03, DRB1*07:01, DRB1*08:02, DRB1*14:02, DRB1*16:02. One of the nine most frequent extended haplotypes seems to be from European origin, suggesting the existence of a degree of admixture with Europeans in our Mapuche sample. It has been calculated of about 11 % admixture. Three of the extended haplotypes are also found in other Amerindians and five of them are newly found in Mapuche Amerindians: A*68:01-B*39:09-DRB1*08:02-DQB1*04:02; A*68:01-B*51:01-DRB1*04:03-DQB1*03:02; A*29:01-B*08:01-DRB1*03:01-DQB1*02:01; A*02:01-B*15:01-DRB1*04:03-DQB1*03:02; A*33:01-B*14:02-DRB1*07:01-DQB1*03:03. The medical importance of calculating HLA profile is discussed on the diagnostic (HLA and disease) and therapeutical bases of HLA pharmacogenomics and on the construction of a virtual transplantation HLA list profile. Also, anthropological conclusions are drawn.     

HLA alleles associated with the adaptive immune response to smallpox vaccine: a replication study

We previously reported HLA allelic associations with vaccinia virus (VACV)-induced adaptive immune responses in a cohort of healthy individuals (n = 1,071 subjects) after a single dose of the licensed smallpox (Dryvax) vaccine. This study demonstrated that specific HLA alleles were significantly associated with VACV-induced neutralizing antibody (NA) titers (HLA-B*13:02, *38:02, *44:03, *48:01, and HLA-DQB1*03:02, *06:04) and cytokine (HLA-DRB1*01:03, *03:01, *10:01, *13:01, *15:01) immune responses. We undertook an independent study of 1,053 healthy individuals and examined associations between HLA alleles and measures of adaptive immunity after a single dose of Dryvax-derived ACAM2000 vaccine to evaluate previously discovered HLA allelic associations from the Dryvax study and determine if these associations are replicated with ACAM2000. Females had significantly higher NA titers than male subjects in both study cohorts [median ID50 discovery cohort 159 (93, 256) vs. 125 (75, 186), p < 0.001; replication cohort 144 (82, 204) vs. 110 (61, 189), p = 0.024]. The association between the DQB1*03:02 allele (median ID₅₀ discovery cohort 152, p = 0.015; replication cohort 134, p = 0.010) and higher NA titers was replicated. Two HLA associations of comparable magnitudes were consistently found between DRB1*04:03 and DRB1*08:01 alleles and IFN-γ ELISPOT responses. The association between the DRB1*15:01 allele with IFN-γ secretion was also replicated (median pg/mL discovery cohort 182, p = 0.052; replication cohort 203, p = 0.014). Our results suggest that smallpox vaccine-induced adaptive immune responses are significantly influenced by HLA gene polymorphisms. These data provide information for functional studies and design of novel candidate smallpox vaccines.     

Timing Light Treatment for Eastward and Westward Travel Preparation

Jet lag degrades performance and operational readiness of recently deployed military personnel and other travelers. The objective of the studies reported here was to determine, using a narrow bandwidth light tower (500 nm), the optimum timing of light treatment to hasten adaptive circadian phase advance and delay. Three counterbalanced treatment order, repeated measures studies were conducted to compare melatonin suppression and phase shift across multiple light treatment timings. In Experiment 1, 14 normal healthy volunteers (8 men/6 women) aged 34.9±8.2 yrs (mean±SD) underwent light treatment at the following times: A) 06:00 to 07:00 h, B) 05:30 to 07:30 h, and C) 09:00 to 10:00 h (active control). In Experiment 2, 13 normal healthy subjects (7 men/6 women) aged 35.6±6.9 yrs, underwent light treatment at each of the following times: A) 06:00 to 07:00 h, B) 07:00 to 08:00 h, C) 08:00 to 09:00 h, and a no-light control session (D) from 07:00 to 08:00 h. In Experiment 3, 10 normal healthy subjects (6 men/4 women) aged 37.0±7.7 yrs underwent light treatment at the following times: A) 02:00 to 03:00 h, B) 02:30 to 03:30 h, and C) 03:00 to 04:00 h, with a no-light control (D) from 02:30 to 03:30 h. Dim light melatonin onset (DLMO) was established by two methods: when salivary melatonin levels exceeded a 1.0 pg/ml threshold, and when salivary melatonin levels exceeded three times the 0.9 pg/ml sensitivity of the radioimmunoasssy. Using the 1.0 pg/ml DLMO, significant phase advances were found in Experiment 1 for conditions A (p?<?.028) and B (p?<?0.004). Experiment 2 showed significant phase advances in conditions A (p?<?0.018) and B (p?<?0.003) but not C (p?<?0.23), relative to condition D. In Experiment 3, only condition B (p?<?0.035) provided a significant phase delay relative to condition D. Similar but generally smaller phase shifts were found with the 2.7 pg/ml DLMO method. This threshold was used to analyze phase shifts against circadian time of the start of light treatment for all three experiments. The best fit curve applied to these data (R²?=?0.94) provided a partial phase-response curve with maximum advance at approximately 9–11 h and maximum delay at approximately 5–6 h following DLMO. These data suggest largest phase advances will result when light treatment is started between 06:00 and 08:00 h, and greatest phase delays will result from light treatment started between 02:00 to 03:00 h in entrained subjects with a regular sleep wake cycle (23:00 to 07:00 h).     

Time or retiring and sleep quality may be predictors of academic performance and psychosomatic disorder in university students

In an effort to improve school performance, we have examined the effect of sleep–wake patterns, particularly time in bed, and morning psychosomatic conditions in adolescents. A psychosomatic disorder questionnaire was administered to 135 physically healthy students, who were divided into four groups according to time they went to bed: 23–24, 24–01, 01–02 and 02–03 h. (1) The 23–24 and 24–01 h groups had significantly higher grade point averages than the 02–03 h group. (2) Partial correlations, controlling for sleep quality, revealed significant associations between time to bed and psychosomatic disorder, with regard to whole-body fatigue, lack of motivation and the desire to rest. Our results suggest that the sleep–wake pattern, especially the time of retiring, may predict academic performance and psychosomatic disorder.     

Anwendung von Dauerkathetern bei weiblichen wachsenden Schweinen zur Trennung von Kot und Harn für Stickstoffbilanz-und Verdaulichkeitsuntersuchungen

The aim of the present experiment was to investigate an experimental brown midrib (Bm) maize hybrid in comparison with a control (Con) non-Bm maize hybrid on ruminal and total tract digestibility, ruminal fermentation, ruminal ingesta kinetics, nitrogen (N) utilisation and microbial efficiency. A total of six ruminally and duodenally cannulated German Holstein cows were used. Animals were fed diets of either 11.5 kg dry matter (DM) of a Con or a Bm maize silage plus 4.1 kg DM of concentrate. Ruminal and total tract digestibility of organic matter, neutral detergent fibre and acid detergent fibre did not differ between hybrids. Short-chain fatty acid concentrations and pH in the rumen were not affected, but ruminal mean retention time was lower for Diet Bm (Con: 45.4 ± 2.39 h; Bm: 40.6 ± 2.39 h; least squares means ± standard error). Cows fed Diet Bm had greater efficiency of N utilisation (Con: 30.1 ± 1.37%; Bm: 33.1 ± 1.37%) and increased flow of microbial crude protein at the duodenum (MCPF) (Con: 7.0 ± 0.37 g/MJ metabolisable energy (ME); Bm: 8.1 ± 0.37 g/MJ ME). Thus, MCPF and utilisable crude protein at the duodenum (uCP) were greater for Diet Bm (MCPF – Con: 1117 ± 52.1 g/d; Bm: 1306 ± 52.1 g/d; uCP – Con: 1594 ± 57.9 g/d; Bm: 1807 ± 57.9 g/d) and ruminal N balance was lower for Diet Bm (Con: 98.7 ± 8.92 g/d; Bm: 65.6 ± 8.92 g/d). The present results show that the Bm maize hybrid might be advantageous for dairy cow nutrition with regard to N utilisation and MCPF. However, further research is necessary to draw more precise conclusions on the potential of Bm maize hybrids in general.     

Influence of various amounts of fumaric acid on performance and parameters of the acid–base balance of growing bulls fed with grass or maize silage

The aim of the present study was to determine the effects of the potential methane reducer fumaric acid on the fattening performance and acid–base balance of growing bulls fed two different silage types as roughage (maize and grass silage). A total of 62 fattening bulls (German Holstein breed, initial body weight: 266 ± 42 kg), randomly assigned to eight feeding groups, received four levels of fumaric acid (0, 100, 200 or 300 g/d) at each silage type. The daily feed and water intake and the live weight were measured over the whole testing period of 280 days. In blood samples, blood cells and blood gases as a parameter of acid–base status were analysed. Feed and faeces were collected to determine the apparent nutrient digestibility. Five animals from each group fed maize or grass silage, supplemented with 0 g or 300 g fumaric acid, were slaughtered at 580 kg body weight. After slaughter, rumen fluid pH was measured and dressing percentage was calculated. Neither the total feed intake (8.81 ± 0.07 kg/d) nor the daily weight gain (1277±24 g/d) was influenced significantly by treatments. Fumaric acid supplementation did not influence the erythrocyte count or the blood gas concentration. The silage type significantly influenced the apparent digestibility of the whole diet. The dressing percentage was slightly higher (p < 0.1) after fumaric acid supplementation. No signs of an incompatibility to fumaric acid on the animals were observed over the whole experimental period. However, it seems to be necessary to conduct more long-term studies with different silage types and addition of organic acids combined with direct measurements of methane.     

Comprehensive identification of high-frequency and co-occurring Mafa-DPA1, Mafa-DQA1, Mafa-DRA, and Mafa-DOA alleles in Vietnamese cynomolgus macaques

High-frequency alleles and/or co-occurring human leukocyte antigen alleles across loci appear to be more important than individual alleles as markers of disease risk and have clinical value as biomarkers for targeted screening or the development of new disease therapies. To better elucidate the major histocompatibility complex (MHC) background and to facilitate the experimental use of cynomolgus macaques, Mafa-DPA1, Mafa-DQA1, Mafa-DRA, and Mafa-DOA alleles were characterized, and their combinations were investigated in 30 Vietnamese macaques by gene cloning and sequencing. A total of 26 Mafa-DPA1, 18 Mafa-DQA1, 9 Mafa-DRA, and 15 Mafa-DOA alleles, including 7 high-frequency alleles, were identified in this study, respectively. In addition, 15 Mafa-DQA1, 17 Mafa-DPA1, 15 Mafa-DOA, and 2 Mafa-DRA alleles represented novel sequences that had not been documented in earlier studies. Our results also showed that the Vietnamese macaques might be valuable because no less than 30 % of the test animals possessed Mafa-DRA*01:02:01 (90 %), -DQA1*26:01:03 (37 %), -DOA*01:02:07 (34 %), and -DQA1*01:03:03 (30 %). We previously reported that the combinations of MHC class II alleles, including the combination of DOA*01:02:07-DPA1*02:09 and DOA*01:02:07-DQA1*01:03:03, were detected in 17 and 14 % of the animals, respectively. Interestingly, more than two Mafa-DQA1 and Mafa-DPA1 alleles were detected in one animal in this study, which suggested that they might be caused by a chromosomal duplication. If our findings can be validated by other studies, it will further enrich the number of known Mafa-DPA1 and Mafa-DQA1 polymorphisms. Our results identified the co-occurring MHC alleles across loci in a cohort of Vietnamese cynomolgus macaques, which emphasized the value of this species as a model for biomedical research.     

Dietary curcumin supplementation effects on blood immunological profile and liver enzymatic activity of laying hens after exposure to high temperature conditions

Various environmental factors affect livestock production but heat stress is a major challenge in the poultry farming. Poultry exposes to high temperature alters blood immunological parameters and liver enzymatic function which in turn, suppress the immunity and disease resistance of chickens. Thus, the purpose of present study was to explore the effect of dietary curcumin supplementation on blood immunological biomarker and liver enzymatic activity of laying hens under heat stress conditions. Experimental groups contained two control groups (normal temperature control (NC) and heat stress control (HC) and 3 heat stress curcumin treatment groups (HT100, HT200 and HT300). Hens in HC group with basal diet and heat stress curcumin treatment groups were exposed 6 h/day heat stress (32 ± 1 °C) from 10:00 a.m. to 16:00 p.m. for 9 week. The results of present study showed that heat stressed curcumin treatment group had improved liver weight, WBC values and immunoglobulin level as compared to untreated HC and NC groups. The available results also indicated that laying hens supplemented with curcumin under high temperature conditions had reduced H/L ratio, serum corticosterone levels, inflammatory cytokines response and liver enzymatic activity (ALT) which enhanced the immunity of laying hens under hot climatic conditions. Therefore, it is concluded that curcumin has ability to combat harsh environmental conditions which can be used as anti-inflammatory and immune booster feed additive in the poultry nutrition.     

Melatonin suppression during a simulated night shift in medium intensity light is increased by 10-minute breaks in dim light and decreased by 10-minute breaks in bright light

ABSTRACT

Exposure to light at night results in disruption of endogenous circadian rhythmicity and/or suppression of pineal melatonin, which can consequently lead to acute or chronic adverse health problems. In the present study, we investigated whether exposure to very dim light or very bright light for a short duration influences melatonin suppression, subjective sleepiness, and performance during exposure to constant moderately bright light. Twenty-four healthy male university students were divided into two experimental groups: Half of them (mean age: 20.0 ± 0.9 years) participated in an experiment for short-duration (10 min) light conditions of medium intensity light (430 lx, medium breaks) vs. very dim light (< 1 lx, dim breaks) and the other half (mean age: 21.3 ± 2.5 years) participated in an experiment for short-duration light conditions of medium intensity light (430 lx, medium breaks) vs. very bright light (4700 lx, bright breaks). Each simulated night shift consisting of 5 sets (each including 50-minute night work and 10-minute break) was performed from 01:00 to 06:00 h. The subjects were exposed to medium intensity light (550 lx) during the night work. Each 10-minute break was conducted every hour from 02:00 to 06:00 h. Salivary melatonin concentrations were measured, subjective sleepiness was assessed, the psychomotor vigilance task was performed at hourly intervals from 21:00 h until the end of the experiment. Compared to melatonin suppression between 04:00 and 06:00 h in the condition of medium breaks, the condition of dim breaks significantly promoted melatonin suppression and the condition of bright breaks significantly diminished melatonin suppression. However, there was no remarkable effect of either dim breaks or bright breaks on subjective sleepiness and performance of the psychomotor vigilance task. Our findings suggest that periodic exposure to light for short durations during exposure to a constant light environment affects the sensitivity of pineal melatonin to constant light depending on the difference between light intensities in the two light conditions (i.e., short light exposure vs. constant light exposure). Also, our findings indicate that exposure to light of various intensities at night could be a factor influencing the light-induced melatonin suppression in real night work settings.     

HLA class I,KIR, and genome-wide SNP diversity in the RV144 Thai phase 3 HIV vaccine clinical trial

RV144 is the first phase 3 HIV vaccine clinical trial to demonstrate efficacy. This study consisted of more than 8,000 individuals in each arm of the trial, representing the four major regions of Thailand. Human leukocyte antigen (HLA) class I and killer cell immunoglobulin-like receptor (KIR) genes, as well as 96 genome-wide ancestry informative markers (AIMs) were genotyped in 450 placebo HIV-1-uninfected individuals to identify the immunogenetic diversity and population structure of this cohort. High-resolution genotyping identified the common HLA alleles as A*02:03, A*02:07, A*11:01, A*24:02, A*24:07, A*33:03, B*13:01, B*15:02, B*18:01, B*40:01, B*44:03, B*46:01, B*58:01, C*01:02, C*03:02, C*03:04, C*07:01, C*07:02, C*07:04, and C*08:01. The most frequent three-loci haplotype was B*46:01-C*01:02-A*02:07. Framework genes KIR2DL4, 3DL2, and 3DL3 were present in all samples, and KIR2DL1, 2DL3, 3DL1, 2DS4, and 2DP1 occurred at frequencies greater than 90 %. The combined HLA and KIR profile suggests admixture with neighboring Asian populations. Principal component and correspondence analyses comparing the RV144 samples to the phase 3 International HapMap Project (HapMap3) populations using AIMs corroborated these findings. Structure analyses identified a distinct profile in the Thai population that did not match the Asian or other HapMap3 samples. This shows genetic variability unique to Thais in RV144, making it essential to take into account population stratification while performing genetic association studies. The overall analyses from all three genetic markers indicate that the RV144 samples are representative of the Thai population. This will inform subsequent host genetic analyses in the RV144 cohort and provide insight for future genetic association studies in the Thai population.     

Effect of napping opportunity at different times of day on vigilance and shuttle run performance

ABSTRACT

The aim of the present study was to examine the effect of a nap opportunity during the daytime realized at different times of day on physical and mental performance. Eighteen physically active males (age: 20.5 ± 3.0 years, height: 175.3 ± 5.9 cm, body-mass: 70.0 ± 8.6 kg) were tested under four experimental conditions: no-nap condition, nap at 13h00, nap at 14h00 and nap at 15h00. All nap durations were of 25-min and all tests were performed at 17h00. They performed a 5-m shuttle run test, which generated measures of the highest distance (HD) and total distance (TD). The rating of perceived exertion (RPE) was recorded after each of the six sprints in the 5-m shuttle run test. Vigilance was measured using a digit cancellation test. The results showed that TD at 17h00 was 4% greater after a nap at 14h00 than in the no-nap condition (+28 m, p < .05) or after the nap at 13h00 (+29 m, p < .05). HD was 8% higher (+9 m, p < .001) after a nap at 14h00 than in the no-nap condition and 7% higher after nap at 15h00 than in the no-nap condition (+7 m, p < .05). In addition, HD was 6% higher after nap at 14h00 (+7 m, p < .01) and 5% higher after nap at 15h00 (+9 m, p < .01) than HD after a nap at 13h00. Napping at 13h00 had no effect on physical performance at 17h00. No significant differences were observed between RPE and vigilance scores in the nap and no-nap conditions. In conclusion, napping for 25 min at 14h00 and 15h00 produces meaningful improvements in responses during repeated short-term maximal exercise tests performed at 17h00. Napping at 13h00 does not. Vigilance, as measured using a digit cancellation test, and RPE scores are not influenced by any of the nap opportunities.     

Impact of an energy- and nutrient-reduced diet containing 10% lignocellulose on animal performance,body composition and egg quality of dual purpose laying hens

In response to ethical concerns regarding the killing of day-old male chicks of layer breeds, the use of dual purpose chickens is increasingly discussed in public while data on nutritional requirements of dual purpose laying hens are not available. The present study examined the impact of an energy- and nutrient-reduced diet containing lignocellulose on performance, body composition and egg quality of dual purpose hens. Female Lohmann Dual chicks were allocated to 12 pens and fed two different diets for 52 weeks: a control (CON) and a treatment diet (LC), based on CON but diluted with 10% lignocellulose. During the trial, animal performance, whole-body composition and egg quality parameters of hens were consistently ascertained. The results showed that LC-fed hens had lower body weights compared to those receiving CON (p < 0.05). During the laying period, feed intake was increased in LC-fed hens (p < 0.001). LC-fed hens showed a higher egg production and egg mass resulting in an improved feed efficiency (p < 0.05) and laid smaller eggs compared to CON-fed hens (p < 0.001). At 52 weeks of age, bodies of LC-fed hens had higher protein and lower fat contents than those fed with CON diet (p ≤ 0.001). Mean body weight was positively correlated to the body fat content (p = 0.004) and body fat content was negatively correlated to the egg production (p = 0.043). Analyses of the egg quality showed that yolk mass at all sampling points and albumen mass at 27 and 42 weeks were lower in hens fed with diet LC compared to those fed with diet CON (p< 0.05). In conclusion, the feeding of energy- and nutrient-reduced diets containing 10% lignocellulose reduced the body fat content and simultaneously improved the laying performance in dual purpose hens.     

Responses to booster hepatitis B vaccination are significantly correlated with genotypes of human leukocyte antigen (HLA)-DPB1 in neonatally vaccinated adolescents

Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) near the human leukocyte antigen (HLA)-DP loci that were significantly correlated with outcomes of hepatitis B virus (HBV) infection. We performed a case–control study nested in a well-characterized cohort of booster recipients to assess whether genetic variants of HLA-DPB1 are also associated with response to hepatitis B (HB) vaccination. The cases and controls were 171 and 510 booster recipients whose post-booster titers of antibodies against HBV surface antigen (anti-HBs) were undetectable and detectable, respectively. The HLA-DPB1 genotype was determined using sequence-based techniques. The frequencies of HLA-DPB1 alleles were significantly different between cases and controls (p = 1.7 × 10^?8). The HLA-DPB1 05:01 and 09:01 alleles were significantly more frequent in the cases, and 02:01:02, 02:02, 03:01:01, 04:01:01, and 14:01, were significantly more frequent in the controls. The adjusted odds ratio (OR) of undetectable post-booster anti-HBs titers was significantly correlated with the number of risk alleles (p for trend = 3.8 × 10^?5). For the number of protective alleles, the trend was significantly inversed (p for trend = 1.3 × 10^?5). As compared with subjects with two risk alleles, adjusted OR were 0.34 (95 % confidence interval [CI] 0.21–0.55) and 0.20 (95 % CI 0.08–0.48) for subjects with 1 and 2 protective alleles, respectively. The HLA-DPB1 02:02, 04:01:01, 05:01 and 09:01 alleles were also significantly correlated with the likelihoods of undetectable pre-booster anti-HBs titers. Our results indicated that HLA-DPB1 is significantly correlated with response to booster HB vaccination in adolescent who had received postnatal active HB vaccination. HLA-DBP1 may also determine the long-term persistence of response to HB vaccination.     

Twenty-four-hour variation of vestibular function in young and elderly adults

ABSTRACT

Animal and human studies demonstrate anatomical and functional links between the vestibular nuclei and the circadian timing system. This promotes the hypothesis of a circadian rhythm of vestibular function. The objective of this study was to evaluate the vestibular function through the vestibulo-ocular reflex using a rotatory chair at different times of the day to assess circadian rhythmicity of vestibular function. Two identical studies evaluating temporal variation of the vestibulo-ocular reflex (VOR) were performed, the first in young adults (age: 22.4 ± 1.5 y), and the second in older adults (70.7 ± 4.7 y). The slow phase velocity and time constant of the VOR were evaluated in six separate test sessions, i.e., 02:00, 06:00, 10:00, 14:00, 18:00, and 22:00 h. In both studies, markers of circadian rhythmicity (temperature, fatigue, and sleepiness) displayed expected usual temporal variation. In young adults, the time constant of the VOR showed variation throughout the day (p < .005), being maximum 12:25 h (06:00 h test session) before the acrophase of temperature circadian rhythm. In older adults, the slow phase velocity and time constant also displayed temporal variation (p < .05). Maximum values were recorded at 10:35 h (06:00 h test session) before the acrophase of temperature circadian rhythm. The present study demonstrates that vestibular function is not constant throughout the day. The implication of the temporal variation in vestibular system in equilibrium potentially exposes the elderly, in particular, to differential risk during the 24 h of losing balance and falling.     

Dynamic feeding low and high methionine diets affect the diurnal rhythm of amino acid transporters and clock related genes in jejunum of laying hens

This study was conducted to investigate effects of dynamic feeding low and high methionine (Met) diets on circadian clock gene expression in jejunum of laying hens. A total of 180 laying hens (Brown Hy-line, 41 weeks old) were allocated into 3 groups with 6 replicates each. The CON group received diet containing 0.30% Met, LH group received low Met diet (0.27% Met) at 07:30 h and high Met diet (0.33% Met) at 15:30 h, while HL group received high Met diet at 07:30 h and low Met diet at 15:30 h. After 10 weeks, jejunum samples were collected at 4 h intervals in a daily cycle initial starting at 07:30 h before feeding. Results showed that dynamic feeding of Met significantly affected the wave of mRNA expression of B0AT1, LAT1, SNAT2, CAT-2, and y⁺LAT2 by feeding regime during a day (P<0.05). Dynamic feeding of Met also influenced the fluctuation of relative mRNA expression of Clock, Bmal1, Cry1, Cry2, Per2, and Per3 significantly in hens during a day (P<0.05). These results demonstrated that dynamic feeding different Met level diets of hens affected the rhythmic fluctuation of amino acid transporters and may affected intestinal function by influencing the clock-related genes further.     

24-hour Pattern in Lag Time of Response by Firemen to Calls for Urgent Medical Aid

The aim of the study was to assess the group 24-h pattern of lag time (LT) in response by regular and volunteer firemen (RFM and VFM) to calls for medical help (CFMH), specifically calls for out-of-hospital cardiac arrest (OHCA). LT, duration in min between a CFMH and departure of service vehicle equipped with a semiautomated defibrillator and generally staffed with four well-trained and ready-to-go FM, represents the integrated duration of several processes, each with separate reaction and decision-making times. The exact time of each CFHM (in min, h, day, month, yr) was recorded electronically, and the exact departure time from the station of the responding FM vehicle was recorded by an on-duty FM. Overall, CFMH made up 53?±?9% (SEM) of all emergencies calls for aid. To standardize the study methods, the reported findings are based on 568 CFMH specifically regarding OHCA that occurred during the 4-yr study span (January 2005 to December 2008). CFMH exhibited a 24-h pattern with a major peak at 10:00?h (mean?±?SEM: n?=?9.5?±?1.6) and major trough at 01:00?h (n?=?1.3?±?0.3; t test, p?<?.001). From year to year and season to season, a 24-h pattern was detected in the total of CFMH/h with two peaks (～10:00 and ～17:00h) and two troughs (～01:00 and ～15:00?h) (analysis of variance [ANOVA], p?<?.01; Cosinor, p?<?.05 to?<?.003), with neither season- nor year-related differences (χ², p?>?.05). In CFMH/h pooled time series, ANOVA-detected differences between the hourly means (p?<?.01), and Cosinor analysis validated a 24-h rhythm (p?<?.002). In raw data, the longest LT, indicative of poorest performance, occurred at 05:00?h (8.8?±?0.7?min) and the trough of LT, indicative of best performance, at 16:00?h (4.3?±?0.8?min (t test, p?<?.02). 24-h patterning in LT was validated both by ANOVA of hourly means (p?<?.0006) and Cosinor analysis (p?<?.05), with longest LT ～05:00?h and shortest LT ～16.00?h for data of the individual yearly time-series data. The 24-h LT rhythm was also validated in the pooled time series by Cosinor (p?<?.0001), with the 24-h mean?±?SEM?=?6?±?0.17?min and acrophase (peak) of 03:00?h?±?88?min (SD). Curve patterns of CFMH/h and LT/h differed widely. As a group phenomenon, the LT 24-h rhythm mimics the 24-h pattern of performance, as demonstrated by many laboratory and field investigations. The stability of the LT rhythm between years and seasons and its weak relationship with the CFMH 24-h pattern favors the hypothesis of an endogenous component or origin. The nighttime trough of performance is presumably linked to the elevated risk of work accidents in the same population of FM.     

Effects of Chromium Propionate on Egg Production,Egg Quality,Plasma Biochemical Parameters,and Egg Chromium Deposition in Late-Phase Laying Hens

This study was conducted to investigate the effects of chromium propionate on egg production, egg quality, plasma biochemical parameters and egg chromium deposition in late-phase laying hens. Four hundred thirty-two 60-weeks old laying hens were divided into four groups of 108 birds per group according to egg production. The dietary treatments consisted of the basal diet adding with 0, 200, 400, and 600 μg/kg chromium as chromium propionate. All laying hens were given feed and water ad libitum for 8 weeks. The addition of 400 μg/kg Cr as chromium propionate increased egg production (P?<?0.01) during the later 4 weeks, but decreased albumen height, yolk color score, and Haugh unit of eggs. Six hundred micrograms per kilogram Cr as chromium propionate supplementation improved shell thickness (P?<?0.05). 200 μg/kg Cr as chromium propionate supplementation decreased the uric acid concentration by 31 % (P?<?0.05). However, supplemental Cr did not affect the egg chromium deposition of hens (P?>?0.05). These data indicated that feeding of late-phase laying hens with chromium propionate could improve egg production, increase eggshell thickness, but do not result in abnormal levels of chromium deposition in eggs.     

Effect of co-substrate feeding on methane yield of anaerobic digestion of <Emphasis Type="Italic">Chlorella vulgaris</Emphasis>

Microalgal production has many advantages over the use of terrestrial plants; therefore, increases in the use of microalgae for energy production can be expected. Algal biomass can be processed anaerobically to methane; however, the unfavorable C/N ratio of the substrate may have an inhibitory effect. The impact of the application of used cooking oil, maize silage, and mill residue on anaerobic co-digestion of the microalgal Chlorella vulgaris was studied in semi-continuous, laboratory-scale digestion. During the full period of the trial involving anaerobic digestion of algae in the case of mono-digestion and co-digestion with used cooking oil, maize silage, and mill residue, the volumetric methane yields were 0.38?±?0.07, 1.56?±?0.26, 1.19?±?0.18, and 1.16?±?0.13 L L^?1, respectively. Trials were carried out to determine the long-term effect of the total solid (TS) content of substrates (co-digestion of C. vulgaris and used cooking oil at 3.8 and 7.2 % of TS, respectively). Both designs could be increased to 5.5 g VS L^?1 d^?1, but a higher TS% resulted in increased methane production and a longer period of decline in the methane yield due to washout. The sharp decrease in methane content at the end of 90 days was accompanied by a reorganization of the methanogenic archaeal community.     

Light Exposure Among Adolescents With Delayed Sleep Phase Disorder: A Prospective Cohort Study

The objective of this study was to compare light exposure and sleep parameters between adolescents with delayed sleep phase disorder (DSPD; n?=?16, 15.3?±?1.8 yrs) and unaffected controls (n?=?22, 13.7?±?2.4 yrs) using a prospective cohort design. Participants wore wrist actigraphs with photosensors for 14 days. Mean hourly lux levels from 20:00 to 05:00?h and 05:00 to 14:00?h were examined, in addition to the 9-h intervals prior to sleep onset and after sleep offset. Sleep parameters were compared separately, and were also included as covariates within models that analyzed associations with specified light intervals. Additional covariates included group and school night status. Adolescent delayed sleep phase subjects received more evening (p?<?.02, 22:00–02:00?h) and less morning (p?<?.05, 08:00–09:00?h and 10:00–12:00?h) light than controls, but had less pre-sleep exposure with adjustments for the time of sleep onset (p?<?.03, 5–7?h prior to onset hour). No differences were identified with respect to the sleep offset interval. Increased total sleep time and later sleep offset times were associated with decreased evening (p?<?.001 and p?=?.02, respectively) and morning (p?=?.01 and p?<?.001, respectively) light exposure, and later sleep onset times were associated with increased evening exposure (p?<?.001). Increased total sleep time also correlated with increased exposure during the 9?h before sleep onset (p?=?.01), and a later sleep onset time corresponded with decreased light exposure during the same interval (p?<?.001). Outcomes persisted regardless of school night status. In conclusion, light exposure interpretation requires adjustments for sleep timing among adolescents with DSPD. Pre- and post-sleep light exposures do not appear to contribute directly to phase delays. Sensitivity to morning light may be reduced among adolescents with DSPD. (Author correspondence: auger.raymond1@mayo.edu)