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Models of modified gravity offer promising alternatives to the concordance Λ cold dark matter (ΛCDM) cosmology to explain the late-time acceleration of the universe. A popular such model is f(R) gravity, in which the Ricci scalar in the Einstein–Hilbert action is replaced by a general function of it. We study the f(R) model of Hu & Sawicki, which recovers standard general relativity in high-density regimes, while reproducing the desired late time acceleration at cosmological scales. We run a suite of high-resolution zoom simulations using the ecosmog code to examine the effect of f(R) gravity on the properties of a halo that is analogous to the Virgo cluster. We show that the velocity dispersion profiles can potentially discriminate between f(R) models and ΛCDM, and provide complementary analysis of lensing signal profiles to explore the possibility to further distinguish the different f(R) models. Our results confirm the techniques explored by Cabré et al. to quantify the effect of environment in the behaviour of f(R) gravity, and we extend them to study halo satellites at various redshifts. We find that the modified gravity effects in our models are most observable at low redshifts, and that effects are generally stronger for satellites far from the centre of the main halo. We show that the screening properties of halo satellites trace very well that of dark matter particles, which means that low-resolution simulations in which subhaloes are not very well resolved can in principle be used to study satellite properties. We discuss observables, particularly for halo satellites, that can potentially be used to constrain the observational viability of f(R) gravity. [ABSTRACT FROM PUBLISHER]

Metal-poor globular clusters (MPGCs) are a unique probe of the early universe, in particular the reionization era. A popular hypothesis is that the observed truncation of MPGC formation is due to reionization. Under this hypothesis, constraining the formation epoch of MPGCs provides a complementary constraint on the epoch of reionization. Moreover, as the earliest reionizing sources first formed in galaxy clusters, systems of globular clusters in galaxy clusters are of particular interest. We provide a self-consistent dark matter only zoom cosmological simulation to perform an analysis of the Virgo cluster globular cluster system by identifying the present-day globular cluster system with early, rare dark matter peaks. By analysing both the line-of-sight velocity dispersion and the surface density profile of the present-day distribution, we are able to constrain the redshift and mass of the dark matter peaks. Although found to be degenerate, we quantify a dependence on the chosen line of sight of these quantities, whose strength varies with redshift. Coupled with star formation efficiency arguments, we find a best-fitting formation mass and redshift of ≃5 × 108 M⊙ and z ≃ 9. We predict ≃300 intracluster MPGCs in the Virgo cluster. Our results confirm the techniques pioneered by Moore et al. when applied to the Virgo cluster and extend and justify the analytic results of Spitler et al. numerically. [ABSTRACT FROM AUTHOR]

ABSTRACTWe determine the orbital parameters of the three subdwarf B (sdB) stars, PG 0101+039, PG 1432+159 and PG 2345+318. We find orbital periods of 13.6778 ± 0.0002, 5.398 ± 0.008 and 5.7827 ± 0.0002 h, respectively. We calculate lower limits for the mass of the companion star in each case. We also suggest upper mass limits for the companions to PG 1432+159 and PG 2345+318 on the basis of the maximum size of the companion allowed by the Roche lobe geometry. The nature of the companion star is discussed but cannot be determined without further observations. We confirm the previously measured period for the sdB binary PG 1101+249 as 8.49 h. [ABSTRACT FROM AUTHOR]

Examines pig and chicken sequence databases observed in the Genbank database. Observation of mononucleotide to tetranucleotide repeats; Frequency of microsatellite repeats in pig and chicken genes; Diversity of microsatellites; Amplification.

The spleens and livers of mice were investigated histologically on various days subsequent to infection with Plasmodium berghei yoelii using immunofluorescence and autoradiography. At the height of the parasitaemia, at a time when non- specific immunosuppression is known to occur, the `thymus-dependent area' round the central arteriole of the spleen was replaced by proliferating lymphoid cells many of which were IgG containing plasmablasts. There was also at this time a considerable decrease in small lymphocytes in this area. The significance of these findings is discussed in relation to the non-specific immunosuppression. In addition evidence for immune complex deposition was obtained in a number of tissues. [ABSTRACT FROM AUTHOR]

Examines the use of sentinel lymph node biopsy in patients with high-risk ductal carcinoma in situ (DCIS). Identification of patients with screen-detected breast cancer; Discovery of invasive cancer in some patients; Facilitation of single-state surgery; Reduction of the need for a second procedure in high-risk DCIS patients.

Short-period double degenerates (DDs) are close white dwarf–white dwarf binary stars which are the result of the evolution of interacting binary stars. We present the first definitive measurements of the mass ratio for two DDs, WD 0136+768 and WD 1204+450, and an improved measurement of the mass ratio for WD 0957-666. We compare the properties of the six known DDs with measured mass ratios to the predictions of various theoretical models. We confirm the result that standard models for the formation of DDs do not predict sufficient DDs with mass ratios close to 1. We also show that the observed difference in cooling ages between white dwarfs in DDs is a useful constraint on the initial mass ratio of the binary. A more careful analysis of the properties of the white dwarf pair WD 1704+481.2 leads us to conclude that the brighter white dwarf is older than its fainter companion. This is the opposite of the usual case for DDs and is caused by the more massive white dwarf being smaller and cooling faster. The mass ratio in the sense (mass of younger star)/(mass of older star) is then 1.43±0.06 rather than the value of 0.70±0.03 given previously. [ABSTRACT FROM AUTHOR]

We present 594 radial velocity measurements for 71 white dwarfs obtained during our search for binary white dwarfs and not reported elsewhere. We identify three excellent candidate binaries, which require further observations to confirm our preliminary estimates for their orbital periods, and one other good candidate. We investigate whether our data support the existence of a population of single, low-mass (≲0.5 M[sub ⊙]) white dwarfs (LMWDs). These stars are difficult to explain using standard models of stellar evolution. We find that a model with a mixed single/binary population is at least ~20 times more likely to explain our data than a pure binary population. This result depends on assumed period distributions for binary LMWDs, assumed companion masses and several other factors. Therefore, the evidence in favour of the existence of a population of single LMWDs is not sufficient, in our opinion, to firmly establish the existence of such a population, but does suggest that extended observations of LMWDs to obtain a more convincing result would be worthwhile. [ABSTRACT FROM AUTHOR]

The North Sea is one of the most studied and exploited ecosystems worldwide. The multiple uses from industrial, transport, as well as recreational activities have required researchers, regulators, and legislators to understand and, where possible, to minimize any expected negative environmental impacts. As with any international sea, assessing the current pressures and management actions resulting from these activities is centred on several national and international legislative instruments. This variety of co-existing legislations makes development processes and regulatory assessments cumbersome and time consuming. Hence there is a need to integrate environmental risk assessment and management across sectors, ensuring smart, cost-effective data generation, as well as supporting and standardizing environmental practices. This paper provides an overview of the changing regulatory frameworks regarding offshore chemicals used in the oil and gas industry, and the process of chemical risk assessment conducted under the Offshore Chemical Notification Scheme (ONCS) in the UK. Our view of methodological, research, and regulatory needs and challenges that should be addressed to ensure an adequate and sustainable assessment of offshore chemical use in the North Sea is discussed. Furthermore, we discuss the issues faced regarding chemicals used in the UK oil and gas sector with respect to declining hydrocarbon production. [ABSTRACT FROM AUTHOR]

We study the polarization properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg2 survey. We estimate the polarized power by stacking maps at known source positions, and correct for noise bias by subtracting the mean polarized power at random positions in the maps. We show that the method is unbiased using a set of simulated maps with similar noise properties to the real SPTpol maps. We find a flux-weighted mean-squared polarization fraction 〈 p 2〉 = [8.9 ± 1.1] × 10−4 at 95 GHz and [6.9 ± 1.1] × 10−4 at 150 GHz for the full sample. This is consistent with the values obtained for a subsample of active galactic nuclei. For dusty sources, we find 95 per cent upper limits of 〈 p 2〉95 < 16.9 × 10−3 and 〈 p 2〉150 < 2.6 × 10−3. We find no evidence that the polarization fraction depends on the source flux or observing frequency. The 1σ upper limit on measured mean-squared polarization fraction at 150 GHz implies that extragalactic foregrounds will be subdominant to the CMB E and B mode polarization power spectra out to at least ℓ ≲ 5700 (ℓ ≲ 4700) and ℓ ≲ 5300 (ℓ ≲ 3600), respectively, at 95 (150) GHz. [ABSTRACT FROM AUTHOR]

This study explored the hypothesis that mannan oligosaccharide (MOS) acts to reduce systemic inflammation in pigs by evaluating cytokine production of alveolar macrophages (AM) and serum cytokine concentrations. A total of 160 pigs were fed diets containing 0.2 or 0.4% MOS for 2 or 4 wk postweaning compared with control diets without MOS. Dietary MOS did not affect the serum concentration of tumor necrosis factor (TNF)-α and tended (P = 0.081) to increase that of IL-10. These cytokine concentrations also changed over time (P < 0.001). After 2-wk feeding of the control or MOS diets, AM were collected and stimulated ex vivo with lipopolysaccharide (LPS) or polyinosinic:polycytidylic acid (PUG) as infection models. The LPS-stimulated AM from MOS-fed pigs (n = 12) secreted less TNF-α (P < 0.001) and more IL-l0 (P = 0.026) than those from control-fed pigs (n = 6). However, dietary MOS had less effect on ex vivo TNF-α and IL-l0 production by PUG-stimulated AM (P = 0.091 and P > 0.10, respectively. Further, effects of MOS were examined in 4 in vitro experiments. In Exp. 1 (n = 4 pigs), MOS and mannan-rich fraction (MRF), when added to AM cultures, were able to increase TNF-α production. This direct effect of MOS was not due to endotoxin contamination as verified in Exp. 2 (n = 6 pigs) using polymyxin B, an inhibitor of LPS activation of toll-like receptor 4. Polymyxin B inhibited production of TNF-α by AM after treatment with LPS (P < 0.001), but not after treatment with MOS in the absence of LPS (P> 0.70). 1:n Exp. 3 (n = 6 pigs), when MOS was directly applied in vitro, the pattern of cytokine production by LPS-activated AM was similar to that observed ex vivo, as MOS suppressed LPS-induced TNF-α (P < 0.001) and enhanced LPS-induced IL-l0 (P = 0.028). In Exp. 4 (n = 6 pigs), when MRF replaced MOS, AM-produced TNF-α induced by LPS or PLIC was suppressed by MRF (P = 0.015 or P < 0.001, respectively). These data establish that MOS and MRF suppress LPS-inducecl TNF-α secretions by AM. Generally, the study suggests that MOS may be a potent immunomodulator because it directly activates AM to secrete TNF-α and alters the cytokine responses of bacterial endotoxinnduced AM in both ex vivo and in vitro systems. particular, feeding MOS to pigs for 2 wk reduces TNF-α. and increases IL-l0 concentrations after ex vivo treatment of AM with LPS. These immunornodulatory properties of MOS may have important implications for both host defense and avoidance of harmful overstimulation of the immune system. [ABSTRACT FROM AUTHOR]

This study characterized gene expression in peripheral blood mononuclear cells (PBMC) and bronchoalveolar lavage fluid (BALF) cells from control- or mannan oligosaccharide (MOS)-fed pigs with or without porcine reproductive and respiratory syndrome virus (PRRSV) at d 7 postinfection (PI). Weaned pigs (3 wk old) fed 0 or 0.2% MOS (Bio-Mos) diets were intranasally inoculated with PRRSV or a sterile medium at 5 wk of age. Total RNA (3 pigs/treatment) was extracted from cells. Double-stranded cDNA was amplified, labeled, and further hybridized to the Affymetrix GeneChip Porcine Genome Array consisting of 23,937 probe sets representing 20,201 genes. Microarray data were analyzed in R using packages from the Bioconductor project. Differential gene expression was tested by fitting a mixed linear model equivalent to a 2 x 2 factorial ANOVA using the limma package. Dietary MOS and PRRSV changed the expression of thousands of probe sets in PBMC and BALF cells (P < 0.05). The MOS x PRRSV interaction altered the expression of more nonimmune probe sets in PBMC (977 up, 1,128 down) than in BALF cells (117 up, 78 down). The MOS x PRRSV interaction (P < 0.05) for immune probe sets in PBMC affected genes encoding key inflammatory mediators. In uninfected pigs, gene expression of IL-1α, IL-6, myeloid differentiation factor 88, Toll-like receptor (TLR) 4, major histocompatibility complex (MHC) II, and dead box polypeptide 58 increased in PBMC of MOS-fed pigs (P < 0.05). This suggests that MOS enhances disease resistance in pigs and supports the fact that MOS induced a rapid increase in leukocytes at d 3 and 7 PI. Within infected pigs, however, MOS reduced the expression of IL-1β, IL-6, IL-8, macrophage inflammatory protein (MIP)-1α, MIP-1β, monocyte chemotactic protein (MCP)-1, and TLR4 genes in PBMC (P < 0.05). This finding may explain why fever was ameliorated in infected pigs fed MOS by d 7 PI. The expression of IL-1β, IL-6, MIP-1β, MCP-1, and TLR4 genes was confirmed by quantitative real-time reverse-transcription PCR. In BALF cells of infected pigs, MOS reduced the gene expression of TLR4, MHCII, and molecules associated with the complement system, but increased the gene expression of MHCI. In short, MOS regulated the expression of nonimmune and immune genes in pig leukocytes, perhaps providing benefits by enhancing the immune responses of the pigs to an infection, while preventing overstimulation of the immune system. [ABSTRACT FROM AUTHOR]

This study was conducted to determine whether the ingestion of mannan oligosaccharide (MOS, Bio-Mos) alters the immune response of nursery pigs challenged with porcine reproductive and respiratory syndrome virus (PRRSV). A total of 64 pigs (3 wk old), free of PRRSV, were used in 2 separate but similar experiments conducted sequentially. Pigs were blocked by initial BW. Sex and ancestry were equalized across treatments. Pigs were randomly assigned from within blocks to 1 of 4 treatments in a 2 × 2 factorial arrangement [2 types of diet: control (0%) and MOS addition (0.2%); 2 levels of PRRSV: with and without]. There were 8 replicate chambers of 2 pigs each. After 2 wk of a 4-wk period of feeding the treatments, pigs were intranasally inoculated with PRRSV or a sterile medium at 5 wk of age. The PRRSV challenge decreased ADG, ADFI, and G:F throughout the experiment (P < 0.001). Feeding MOS improved G:F of the pigs during d 7 to 14 (P = 0.041) postinfection (PI). Serum concentrations of tumor necrosis factor (TNF)-a, C-reactive protein, and haptoglobin were increased by PRRSV (P < 0.001). The MOS × PRRSV interaction was significant for TNF-a at d 14 PI (P = 0.028), suggesting that infected pigs fed MOS had less TNF-a than those fed the control. Dietary MOS increased serum IL-10 at d 14 PI (P = 0.036). Further, MOS-fed pigs had greater numbers of white blood cells (WBC) at d 3 (P = 0.048) and 7 PI (P = 0.042) and lymphocytes at d 7 PI (P = 0.023) than control-fed pigs. In contrast, PRRSV decreased (P < 0.01) WBC numbers until d 14 PI. Dietary MOS appeared (P = 0.060) to increase the neutrophils in PRRSV-infected pigs at d 3 PI, but no (P = 0.202) MOS × PRRSV interaction was found. Infection with PRRSV increased rectal temperature (RT) of pigs at d 3 PI (P < 0.001) and continued to affect the infected pigs fed the control diet until d 14 PI. The MOS × PRRSV interaction for RT was found at d 7 (P < 0.01) and 10 (P = 0.098) PI, indicating that the infected pigs fed MOS had a decreased RT compared with those fed the control. This could explain why feed efficiency was improved by MOS. No effect (P > 0.05) of treatments on viremia or PRRSV-specific antibody was observed. These results suggest that MOS is associated with rapidly increased numbers of WBC at the early stage of infection and alleviates PRRSV-induced effects on G:F and fever. The results also indicate that the reduced intensity of inflammation by MOS may be related to changes in inflammatory mediator levels at the end of the acute phase. [ABSTRACT FROM AUTHOR]

We determine the orbits of four double-degenerate systems (DDs), composed of two white dwarfs and two white-dwarf–M-dwarf binaries. The four DDs, WD1022+050, WD1428+373, WD1824+040 and WD2032+188, show orbital periods of 1.157 155(5), 1.156 74(2), 6.266 02(6) and 5.0846(3) d, respectively. These periods combined with estimates for the masses of the brighter component, based on their effective temperatures, allow us to constrain the masses of the unseen companions. We estimate that the upper limit for the contribution of the unseen companions to the total luminosity in the four DDs ranges between 10 and 20 per cent. In the case of the two white-dwarf–M-dwarf binaries, WD1042−690 and WD2009+622, we calculate the orbital parameters by fitting simultaneously the absorption line from the white dwarf and the emission core from the M dwarf. Their orbital periods are 0.337 083(1) and 0.741 226(2) d, respectively. We find signatures of irradiation on the inner face of the companion to WD2009+622. We calculate the masses of both components from the gravitational redshift and the mass–radius relationship for white dwarfs and find masses of 0.75–0.78 andfor WD1042−690 and WD2009+622, respectively. This indicates that the stars probably reached the asymptotic giant branch in their evolution before entering a common envelope phase. These two white-dwarf–M-dwarf binaries will become cataclysmic variables, although not within a Hubble time, with orbital periods below the period gap. [ABSTRACT FROM AUTHOR]

Fifteen microsatellite loci were evaluated in farmed saltwater crocodiles for use in parentage testing. One marker (C391) could not be amplied. For the remaining 14, the number of alleles per locus ranged from two to 16, and the observed heterozygosities ranged from 0.219 to 0.875. The cumulative exclusion probability for all 14 loci was .9988. The II loci that showed the greatest level of polymorphism were used for parentage testing, with an exclusion probability of .9980. With these II markers on 107 juveniles from 16 known-breeding pairs, a 5.6% pedigree error rate was detected. This level of pedigree error, if consistent, could have an impact on the accuracy of genetic parameter and breeding value estimation. The usefulness of these markers was also evaluated for assigning parentage in situations where maternity, paternity, or both may not be known. In these situations, a 2% error in parentage assignment was predicted. It is therefore recommended that more micro-satellite markers be used in these situations. The use of these microsatellite markers will broaden the scope of a breeding program, allowing progeny to be tested from adults maintained in large breeding lagoons for selection as future breeding animals. [ABSTRACT FROM AUTHOR]

Studies the systemic velocities of four long-period cataclysmic variable stars. Accretion discs; Cataclysmic variables; Radial velocities.

Introduction: The NHFD has collaborated with the Royal College of Surgeons' Clinical Effectiveness Unit to measure the impact of hip fracture on NHS inpatient bed occupancy.Methods: For the year from April 2011 we used data on 64,993 patients from national databases: Health Episode Statistics (HES) in England, Patient Episode Database Wales (PEDW), and the Fracture Outcome Research Database (FORD) in Northern Ireland. Linking acute, post-acute, and rehabilitation elements of each patient's care allowed us to define ‘super-spell’: their overall length of stay in the hospital to which they presented, and in other trusts or organisations to which they were subsequently transferred.Results: Combining NHFD data with that from HES, PEDW and FORD gave figures for overall ‘super-spell’, which were used to calculate bed occupancy.Total bed daysAdmissions‘Super-spell’England1,335,24059,34422.5Wales133,5203,80435.1Northern Ireland61,4391,84533.3Overall1,499,59364,99323.1Cross-referencing with HES, PEDW and FORD suggested the National Hip Fracture Database had captured data on 95% of all presentations, but may have underestimated overall length of stay because of poor access to discharge dates. This was particularly evident when patients moved between organisations during rehabilitation.Conclusions: The HES figure for mean super-spell in England was 22.5 days, but this figure may still have understated NHS costs, since HES captures intermediate care provided in acute and community hospitals, but not NHS funded rehabilitation in care homes. Our analysis shows that patients with hip fracture accounted for 1.5 million bed days in the year. This equates with continuous occupation of 4,106 beds across the NHS at any one time – the equivalent of several district general hospitals catering just for this one condition. [ABSTRACT FROM AUTHOR]

Introduction: The NHFD has collaborated with the Royal College of Surgeons' Clinical Effectiveness Unit to measure the impact of hip fracture on NHS inpatient bed occupancy.Methods: For the year from April 2011 we used data on 64,993 patients from national databases: Health Episode Statistics (HES) in England, Patient Episode Database Wales (PEDW), and the Fracture Outcome Research Database (FORD) in Northern Ireland. Linking acute, post-acute, and rehabilitation elements of each patient's care allowed us to define ‘super-spell’: their overall length of stay in the hospital to which they presented, and in other trusts or organisations to which they were subsequently transferred.Results: Combining NHFD data with that from HES, PEDW and FORD gave figures for overall ‘super-spell’, which were used to calculate bed occupancy.Total bed daysAdmissions‘Super-spell’England1,335,24059,34422.5Wales133,5203,80435.1Northern Ireland61,4391,84533.3Overall1,499,59364,99323.1Cross-referencing with HES, PEDW and FORD suggested the National Hip Fracture Database had captured data on 95% of all presentations, but may have underestimated overall length of stay because of poor access to discharge dates. This was particularly evident when patients moved between organisations during rehabilitation.Conclusions: The HES figure for mean super-spell in England was 22.5 days, but this figure may still have understated NHS costs, since HES captures intermediate care provided in acute and community hospitals, but not NHS funded rehabilitation in care homes. Our analysis shows that patients with hip fracture accounted for 1.5 million bed days in the year. This equates with continuous occupation of 4,106 beds across the NHS at any one time – the equivalent of several district general hospitals catering just for this one condition. [ABSTRACT FROM PUBLISHER]

Evidence-base: The timely management of hip fractures is now underpinned by NICE Guidance, June 2011. This includes a statement that magnetic resonance imaging (MRI) should be offered if occult femoral neck fracture is suspected and that MRI should be made available within 24 hours.We conducted a full cycle audit to: 1) analyse the time taken for inpatient MRI to be performed for occult femoral neck fracture 2) identify remediable reasons for delay 3) develop and implement changes 4) re-audit.Method: Data was collected from the computerised radiology information system on consecutive patients between 01/04/2010 and 31/03/2012. This data was presented at a number of directorate audit meetings. Following the development and implementation of targeted improvements, a prospective re-audit was carried out from 01/08/2012 to 31/07/2013.Results: Baseline audit and re-audit results are tabulated below. The remediable causes for delay were 1) duty radiologist not directly contacted by clinician to request urgent scan 2) slow vetting and protocolling of electronic requests 3) resistance to weekend scanning 4) delay in completing MRI safety questionnaire.After enacting strategies to address these remediable causes of delay, the re-audit showed a 16% improvement in patients scanned within 24hrs. The mean waiting time to get an MRI was 2025.4 minutes (SD 2406.4) for the baseline audit and 1374 minutes (SD 1635.7) for the re-audit. Mean difference 651.4 minutes (95% CI 85.21, 1217.5, p = 0.0243).Total number of patientsScans done within 24 hrs (%)Scans done within 36 hrs (%)Average waiting time in hrsAUDIT (2 yrs data)167566634RE-AUDIT (12 months data)87728123Conclusion: MRI is a useful and sensitive tool to investigate occult femoral neck fracture (FrihagenF, Acta Orthop2005Aug;76(4):524-30). Inpatient MRI waiting times can significantly be reduced by a targeted approach which embodies improved team working. [ABSTRACT FROM AUTHOR]

Discusses research being done on social deprivation and osteoporotic low trauma fractures in older people. Reference to study by I. Morgan et al, presented at the British Geriatrics Society Communications to the Autumn Meeting in Harrogate, England from October 6 to 8, 2004; Relationship between social deprivation and osteoporotic fractures; Methodology and result of the study.