The effects of heat stress on the development of the foetal lamb

Environmental heat stress in tropical sheep suppressed lamb birth weight, but the animals which did not experience hyperthermia under natural environmental conditions gave birth to significantly heavicr (P<0.01) lambs than their less adapted counterparts. Climate chamber studies designed to simulate the rectal temperature patterns of tropical sheep demonstrated that, without nutritional intervention, heat stress during the last month of pregnancy significantly retarded foetal growth (birth weight 2.3 kg v. 3.4 kg; P< 0.01) and maturation of wool follicles (P< 0.01). By comparison, severe nutritional restrictions during the last 3 months of pregnancy also caused a significant reduction in lamb birth weight (3.2 kg v. 3.9 kg; P<O.01), but this difference was not so marked

Three Novel Pigmentation Mutants Generated by Genome-Wide Random ENU Mutagenesis in the Mouse

Three mutant mice with pigmentation phenotypes were recovered from a genomewide random mouse chemical mutagenesis study. White toes (Whto; MGI:1861986), Belly spot and white toes (Bswt; MGI:2152776) and Dark footpads 2 (Dfp2; MGI:1861991) were identified following visual inspection of progeny from a male exposed to the point mutagen ethylnitrosourea (ENU). In order to rapidly localize the causative mutations, genome-wide linkage scans were performed on pooled DNA samples from backcross animals for each mutant line. Whto was mapped to proximal mouse chromosome (Mmu) 7 between Cen (the centromere) and D7Mit112 (8.0 cM from the centromere), Bswt was mapped to centric Mmul between D1Mit214 (32.1 cM) and D1Mit480 (32.8 cM) and Dfp2 was mapped to proximalMmu4 between Cen and D4Mit18 (5.2 cM). Whto, Bswt and Dfp2 may provide novel starting points in furthering the elucidation of genetic and biochemical pathways relevant to pigmentation and associated biological processes

A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope

Globular clusters with their large populations of millisecond pulsars (MSPs) are believed to be potential emitters of high-energy gamma-ray emission. Our goal is to constrain the millisecond pulsar populations in globular clusters from analysis of gamma-ray observations. We use 546 days of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to study the gamma-ray emission towards 13 globular clusters. Steady point-like high-energy gamma-ray emission has been significantly detected towards 8 globular clusters. Five of them (47 Tucanae, Omega Cen, NGC 6388, Terzan 5, and M 28) show hard spectral power indices $(0.7 < \Gamma <1.4)$ and clear evidence for an exponential cut-off in the range 1.0-2.6 GeV, which is the characteristic signature of magnetospheric emission from MSPs. Three of them (M 62, NGC 6440 and NGC 6652) also show hard spectral indices $(1.0 < \Gamma < 1.7)$, however the presence of an exponential cut-off can not be unambiguously established. Three of them (Omega Cen, NGC 6388, NGC 6652) have no known radio or X-ray MSPs yet still exhibit MSP spectral properties. From the observed gamma-ray luminosities, we estimate the total number of MSPs that is expected to be present in these globular clusters. We show that our estimates of the MSP population correlate with the stellar encounter rate and we estimate 2600-4700 MSPs in Galactic globular clusters, commensurate with previous estimates. The observation of high-energy gamma-ray emission from a globular cluster thus provides a reliable independent method to assess their millisecond pulsar populations that can be used to make constraints on the original neutron star X-ray binary population, essential for understanding the importance of binary systems in slowing the inevitable core collapse of globular clusters.Comment: Accepted for publication in A&A. Corresponding authors: J. Kn\"odlseder, N. Webb, B. Pancraz

Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the Universe

The Extragalactic Background Light (EBL) includes photons with wavelengths from ultraviolet to infrared, which are effective at attenuating gamma rays with energy above ~10 GeV during propagation from sources at cosmological distances. This results in a redshift- and energy-dependent attenuation of the gamma-ray flux of extragalactic sources such as blazars and Gamma-Ray Bursts (GRBs). The Large Area Telescope onboard Fermi detects a sample of gamma-ray blazars with redshift up to z~3, and GRBs with redshift up to z~4.3. Using photons above 10 GeV collected by Fermi over more than one year of observations for these sources, we investigate the effect of gamma-ray flux attenuation by the EBL. We place upper limits on the gamma-ray opacity of the Universe at various energies and redshifts, and compare this with predictions from well-known EBL models. We find that an EBL intensity in the optical-ultraviolet wavelengths as great as predicted by the "baseline" model of Stecker et al. (2006) can be ruled out with high confidence.Comment: 42 pages, 12 figures, accepted version (24 Aug.2010) for publication in ApJ; Contact authors: A. Bouvier, A. Chen, S. Raino, S. Razzaque, A. Reimer, L.C. Reye

Supporting activity engagement by family carers at home: maintenance of agency and personhood in dementia

Objective: An explorative paper to describe how family carers, through the caregiving journey, reaffirm and promote the agency of people with dementia. Agency is an important concept in dementia care; and is crucial to the promotion of wellbeing and the delivery of person-centred care. This article is based on one of the key findings of a study that explored family carers’ experiences of engaging their relatives in daily activities in domestic settings. Method: Following research governance and ethical approval, 30 in-depth interviews (initial and follow-up) were carried out with 15 resident-carers of people with dementia who were recruited via local community mental health teams. Then five focus groups were conducted with 21 participants accessed through carers support groups. Interviews and focus groups were transcribed, coded and analysed using a grounded theory method. Results: Findings showed the process in which family carers encouraged and sustained a sense of autonomy and control (agency) in their relative’s daily activities. Key strategies used by carers included: being non-judgemental; facilitating a sense of worth; taking calculated risks; maintaining the continuity of their relative’s identity; enhancing a sense of connection with their relative’s role and identity, using enjoyable activities; preventing inactivity and attending to the bodily source of the agency. Lack of support for carers could ultimately pose a risk to the maintenance of the agency of people with dementia. Conclusion: This study provides a deeper insight into the process used by home carers to support the agency of people with dementia. This is essential if practitioners are to identify and develop more realistic intervention strategies and to work in effective partnership with family carers. The implications for the creation of dementia-friendly communities are discussed