In this study, 20 young steers received no beta-agonist (C), 100 animals all received zilpaterol hydrochloride (Z), with 1 group only receiving Z while the other 4 groups received zilpaterol and ...vitamin D3 at the following levels (IU/animal/day) and durations before slaughter: 7million for 3days (3D7M); 7 million for 6days (6D7M); 7million for 6days with 7days no supplementation (6D7M7N) and 1million for 9days (9D1M). Left carcass sides were electrically stimulated (ES) and the right side not stimulated (NES). Samples were aged for 3 or 14days post mortem. Parameters included Warner–Bratzler shear force (WBSF), myofibril filament length, sarcomere length and calpastatin and calpain enzyme activity.
Both ES and prolonged aging reduced WBSF (P<0.001). 6D7M, 6D7M7N and Z remained significantly tougher than C (P<0.001), while 3D7M and 9D1M improved WBSF under NES conditions. ES is more effective to alleviate beta-agonist induced toughness than high vitamin D3 supplements.
► Beta-agonists improve production efficiency but are detrimental to meat quality. ► High vitamin D3 supplements may enhance calcium mediated proteolysis. ► Vitamin D3 supplements could not overcome beta agonist induced toughness. ► Electrical stimulation and prolonged aging is more effective to improve tenderness.
Although fetomaternal disproportion is the major cause of dystocia in heifers, pelvis area (PA) is not recommended as a culling tool due to its relatively low importance and genetic correlation with ...calf birth weight (BWT), the most important factor associated with dystocia. The objective of this observational study of 484 limited bred yearling beef heifers was to compare the effects of different methods of adjustment of PA data for culling to select against dystocia. Multivariable analyses were used to determine predictors of PA, calf BWT, and dystocia. Hypothetical culling rates of 10 and 20% were then applied after ranking heifers by each of the following: unadjusted PA, PA adjusted to 365 d of age by subtracting 0.27 cm(2) per day of age difference between each heifer's age and 365 d (APA), PA:prebreeding BW ratio (PA:BW), PA adjusted to the median BW of the group using the regression coefficient of PA on BW within age group (BWPA), and PA similarly adjusted to the median lean BW (LBWPA). Dam parity, sire, prebreeding age, prebreeding BW, and prebreeding BCS were associated with PA whereas dam parity, sire, own BWT, PA, AI bull, and calf gender were associated with calf BWT (P < 0.05). Dam parity, calf BWT, and either BWPA or LBWPA were the only independent predictors of dystocia (P < 0.05). Adjusting PA to BW or lean BW (LBW) improved the sensitivity and specificity to predict dystocia. After hypothetical culling by PA, retained heifers were heavier and had a higher calving rate and calves tended to be heavier at birth compared to culled heifers, but dystocia rates were not different. Culling by APA resulted in similar effects, except that dystocia rate tended to be lower in retained heifers. Culling by PA:BW resulted in lower dystocia rate in retained than in culled heifers, but retained heifers had lower prebreeding BW than culls. Culling by BWPA and LBWPA resulted in lower proportions with dystocia and a tendency towards higher calving rates in the retained heifers, without affecting the prebreeding BW or calf BWT. It is concluded that pelvimetry is a useful culling tool to aid in the management of dystocia in yearling heifers and that adjustment of PA to median BW or LBW within age group improves its accuracy and avoids the undesirable side effects.
The presence of Aedes albopictus (Skuse) in the Torres Strait of northern Australia increases the potential for colonization and establishment on the mainland. However, there is a possibility that ...native species that occupy the same habitats may influence the population performance of Ae. albopictus, potentially affecting the establishment of this species in Australia. Cohabitation experiments were performed with the endemic Aedes notoscriptus (Skuse), which has been found occupying the same larval habitats as Ae. albopictus in the Torres Strait and is the most widespread container-inhabiting Aedes species in Australia. The influence of environmental factors and cohabitation between the two species was examined using different climates, food resource levels, food resource types, and species densities. Survivorship proportions and a population performance index (λ') were calculated and compared. The consequences of increased Ae. notoscriptus densities were reduced survivorship and λ' for Ae. albopictus. Despite this, the mean λ' of Ae. albopictus and Ae. notoscriptus was consistently ≥ 1.06, indicating both species could increase under all conditions, potentially due to increasing conspecific densities negatively affecting Ae. notoscriptus. The outcomes from this study suggest that the preexisting presence of Ae. notoscriptus may not prevent the establishment of Ae. albopictus in Australia.
LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. ...Using a two-phase xenon detector with an active mass of 7 tonnes, LZ will search primarily for low-energy interactions with weakly interacting massive particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000 live day run using a 5.6-tonne fiducial mass, LZ is projected to exclude at 90% confidence level spin-independent WIMP-nucleon cross sections above 1.4 × 10−48 cm2 for a 40 GeV/c2 mass WIMP. Additionally, a 5 σ discovery potential is projected, reaching cross sections below the exclusion limits of recent experiments. For spin-dependent WIMP-neutron(-proton) scattering, a sensitivity of 2.3 × 10−43 cm2 (7.1 × 10−42 cm2) for a 40 GeV/c2 mass WIMP is expected. With underground installation well underway, LZ is on track for commissioning at SURF in 2020.
We report heterozygous mutations in the genes encoding either type I or type II transforming growth factor β receptor in ten families with a newly described human phenotype that includes widespread ...perturbations in cardiovascular, craniofacial, neurocognitive and skeletal development. Despite evidence that receptors derived from selected mutated alleles cannot support TGFβ signal propagation, cells derived from individuals heterozygous with respect to these mutations did not show altered kinetics of the acute phase response to administered ligand. Furthermore, tissues derived from affected individuals showed increased expression of both collagen and connective tissue growth factor, as well as nuclear enrichment of phosphorylated Smad2, indicative of increased TGFβ signaling. These data definitively implicate perturbation of TGFβ signaling in many common human phenotypes, including craniosynostosis, cleft palate, arterial aneurysms, congenital heart disease and mental retardation, and suggest that comprehensive mechanistic insight will require consideration of both primary and compensatory events.
The sensory attributes of dark, firm and dry (DFD) and normal pH beef, both raw and fried, were evaluated and compared by a consumer panel (
n=64). Consumer sensory evaluations indicated that the ...general appearance (
P<0.05), colour (
P<0.001) and acceptability (
P<0.01) of raw normal pH steaks were preferred to those of raw DFD steaks. Twice as many panellists preferred the raw normal pH than raw DFD steaks because of the more attractive red colour, compared to the almost black colour of raw DFD steaks. No significant differences were found between the hedonic ratings of the sensory attributes of fried normal pH and fried DFD steaks. It was expected but not confirmed that consumers would find the tenderness of the DFD steaks more acceptable compared to the normal pH steaks. However, when forced to choose, female consumers significantly preferred fried normal pH steaks to fried DFD steaks, presumably because of a better flavour and more acceptable colour.
Background: Little is known about cough frequency in adults with cystic fibrosis (CF). This study aimed to determine (1) daytime and overnight cough rates in patients with CF at the beginning and end ...of a course of antibiotics for treatment of an exacerbation; (2) the relationship between cough frequencies and standard clinical measures of disease; and (3) the relationship between objective cough rates and the subjective assessment of cough. Methods: Nineteen adult patients admitted with a pulmonary exacerbation performed daytime and overnight sound recordings on admission; 13 had repeat recordings prior to discharge. Coughs were manually quantified in cough seconds (time spent coughing). Patients subjectively scored their cough using a visual analogue scale (VAS) and numerical score. Lung function, C-reactive protein (CRP) levels, and sputum weights were recorded. Results: Cough rates fell substantially with treatment; median fall in cough rate was 51.3% (IQR 32.3–77.5) (p<0.001) for daytime and 72.2% (28.6–90.1) (p = 0.049) for overnight. Multivariate regression analyses showed that forced expiratory volume in 1 second and CRP levels predicted overnight cough rates on admission. On discharge, sputum volume predicted daytime cough rates. Only the change in overnight VAS correlated with the change in objective cough rates. Conclusions: The cough rate significantly decreases with treatment of a pulmonary exacerbation in adults with CF. Lung function, sputum volume, and CRP influences the cough rate, with the effects differing from day to night and between admission and discharge. Subjective reporting of a nocturnal cough may indicate a pulmonary exacerbation of CF in adults.
Kinetic limitations in the Mg–Si–H system Paskevicius, M.; Sheppard, D.A.; Chaudhary, A.-L. ...
International journal of hydrogen energy,
08/2011, Letnik:
36, Številka:
17
Journal Article
Recenzirano
Magnesium silicide (Mg
2Si) has attracted interest as a hydrogen storage material due to favorable thermodynamics (Δ
H
desorption = 36 kJ/mol H
2) for room temperature operation. To date, direct ...hydriding of Mg
2Si under hydrogen gas to form MgH
2 and Si has only been attempted at low pressure and has been hindered by poor kinetics of absorption. In this paper we study the dehydrogenation reaction with
in-situ neutron powder diffraction and present results of our attempts to hydrogenate Mg
2Si under both hydrogen and deuterium gas up to temperatures of 350 °C and pressures of 1850 bar. Even under these extreme absorption conditions Mg
2Si does not absorb any measureable quantity of hydrogen or deuterium.
► Poor hydrogen desorption kinetics from MgH
2 & Si below 250 °C. ► Hydrogen absorption of Mg
2Si kinetically limited and unfeasible below 1850 bar up to 350 °C. ► Hydrogenation of Mg
2Si at low pressure and temperature will only be possible with highly effective catalysts.
Parasitic chytrid fungi have emerged as a significant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into culture for research purposes. ...However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modified a pre-existing protocol for isolating chytrids from infected animals to use toe clips and biopsies from toe webbing rather than euthanizing hosts, and distributed the protocol to researchers as part of the BiodivERsA project RACE; here called the RML protocol. In tandem, we developed a lethal procedure for isolating chytrids from tadpole mouthparts. Reviewing a database of use a decade after their inception, we find that these methods have been applied across 5 continents, 23 countries and in 62 amphibian species. Isolation of chytrids by the non-lethal RML protocol occured in 18% of attempts with 207 fungal isolates and three species of chytrid being recovered. Isolation of chytrids from tadpoles occured in 43% of attempts with 334 fungal isolates of one species (Batrachochytrium dendrobatidis) being recovered. Together, these methods have resulted in a significant reduction and refinement of our use of threatened amphibian species and have improved our ability to work with this group of emerging pathogens.
Major depressive disorder (MDD) is a common illness accompanied by considerable morbidity, mortality, costs, and heightened risk of suicide. We conducted a genome-wide association meta-analysis based ...in 135,458 cases and 344,901 controls and identified 44 independent and significant loci. The genetic findings were associated with clinical features of major depression and implicated brain regions exhibiting anatomical differences in cases. Targets of antidepressant medications and genes involved in gene splicing were enriched for smaller association signal. We found important relationships of genetic risk for major depression with educational attainment, body mass, and schizophrenia: lower educational attainment and higher body mass were putatively causal, whereas major depression and schizophrenia reflected a partly shared biological etiology. All humans carry lesser or greater numbers of genetic risk factors for major depression. These findings help refine the basis of major depression and imply that a continuous measure of risk underlies the clinical phenotype.
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