625 research outputs found

    The Accelerated Recombination, and the ACBAR and WMAP data

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    We have investigated the deviation from the standard recombination process, using the ACBAR 2008 and the WMAP 3 year data. In this investigation, we have considered the possibility of the accelerated recombination as well as the delayed recombination. We find that the accelerated recombination is as likely as the delayed recombination, and there is some degeneracy between ϵα\epsilon_{\alpha} and \{nsn_s, log[1010As]\log[10^{10}A_s], H0H_0\}.Comment: v2: matched with the accepted version (minor change) v3: typo corrections v4: a duplicated pdf file fixe

    New insights into foreground analysis of the WMAP five-year data using FASTICA

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    In this paper, we present a foreground analysis of the WMAP 5-year data using the FASTICA algorithm, improving on the treatment of the WMAP 3-year data in Bottino et al 2008. We revisit the nature of the free-free spectrum with the emphasis on attempting to confirm or otherwise the spectral feature claimed in Dobbler et al 2008b and explained in terms of spinning dust emission in the warm ionised medium. With the application of different Galactic cuts, the index is always flatter than the canonical value of 2.14 except for the Kp0 mask which is steeper. Irrespective of this, we can not confirm the presence of any feature in the free-free spectrum. We experiment with a more extensive approach to the cleaning of the data, introduced in connection with the iterative application of FASTICA. We confirm the presence of a residual foreground whose spatial distribution is concentrated along the Galactic plane, with pronounced emission near the Galactic center. This is consistent with the WMAP haze detected in Finkbeiner 2004. Finally, we attempted to perform the same analysis on full-sky maps. The code returns good results even for those regions where the cross-talk among the components is high. However, slightly better results in terms of the possibility of reconstructing a full-sky CMB map, are achieved with a simultaneous analysis of both the five WMAP maps and foreground templates. Nonetheless, some residuals are still present and detected in terms of an excess in the CMB power spectrum, on small angular scales. Therefore, a minimal mask for the brightest regions of the plane is necessary, and has been defined.Comment: Accepted for publication in MNRAS, 25 pages, 17 figures, 4 tables. Version with full resolution figures available at: http://www.mpa-garching.mpg.de/~bottino/downloads/bottino_etal.pd

    CMB E/B decomposition of incomplete sky: a pixel space approach

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    CMB polarization signal may be decomposed into gradient-like (E) and curl-like (B) mode. We have investigated E/B decomposition in pixel space. We find E/B mixing due to incomplete sky is localized in pixel-space, and negligible in the regions far away from the masked area. By estimating the expected local leakage power, we have diagnosed ambiguous pixels. Our criteria for ambiguous pixels (i.e. r_c) is associated with the tensor-to-scalar ratio of B mode power spectrum, which the leakage power is comparable to. By setting r_c to a lower value, we may reduce leakage level, but reduce sky fraction at the same time. Therefore, we have solved \partial \Delta C_l/\partial r_c=0, and obtained the optimal r_c, which minimizes the estimation uncertainty, given a foreground mask and noise level. We have applied our method to a simulated map blocked by a foreground (diffuse + point source) mask. Our simulation shows leakage power is smaller than primordial (i.e. unlensed) B mode power spectrum of tensor-to-scalar ratio r\sim 10^{-3} at wide range of multipoles (50\lesssim l \lesssim 2000), while allowing us to retain sky fraction ~ 0.48.Comment: v2: the point of the method strengthened, v3: criteria for ambiguous pixels rigorously derived, v4: matched with the accepted version in A&A (minor change), v5: typos correcte

    Laparoscopic simulation training in gynaecology:Current provision and staff attitudes - a cross-sectional survey

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    <p>The objectives of this study were to explore current provision of laparoscopic simulation training, and to determine attitudes of trainers and trainees to the role of simulators in surgical training across the UK. An anonymous cross-sectional survey with cluster sampling was developed and circulated. All Royal College of Obstetricians and Gynaecologists (RCOG) Training Programme Directors (TPD), College Tutors (RCT) and Trainee representatives (TR) across the UK were invited to participate. One hundred and ninety-six obstetricians and gynaecologists participated. Sixty-three percent of hospitals had at least one box trainer, and 14.6% had least one virtual-reality simulator. Only 9.3% and 3.6% stated that trainees used a structured curriculum on box and virtual-reality simulators, respectively. Respondents working in a Large/Teaching hospital (<i>p</i> = 0.008) were more likely to agree that simulators enhance surgical training. Eighty-nine percent agreed that simulators improve the quality of training, and should be mandatory or desirable for junior trainees. Consultants (<i>p</i> = 0.003) and respondents over 40 years (<i>p</i> = 0.011) were more likely to hold that a simulation test should be undertaken before live operation. Our data demonstrated, therefore, that availability of laparoscopic simulators is inconsistent, with limited use of mandatory structured curricula. In contrast, both trainers and trainees recognise a need for greater use of laparoscopic simulation for surgical training.</p

    Ultraviolet irradiation accelerates apoptosis in human polymorphonuclear leukocytes: protection by LPS and GM‐CSF

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    Polymorphonuclear leukocytes (PMN) play a central role in host response to injury and infection. Understanding factors that regulate PMN survival may therefore have a major influence on the development of novel treatment strategies for controlling life‐threatening infections, as well as local and systemic inflammatory responses. Unfortunately, the presently utilized in vitro culture model of PMN apoptosis makes the examination of early biochemical events surrounding PMN apoptosis very difficult. This study demonstrates that a short course of UV irradiation (15 min) can be used to induce rapid progression of PMN through the apoptotic process with 70–90% of PMN displaying features of apoptosis by 4 h after UV exposure. Bacterial lipopolysaccharide and granulocyte‐macrophage colony‐stimulating factor, which are known to prolong PMN survival during in vitro culture, also protected PMN from UV‐accelerated apoptosis. The UV‐accelerated model of PMN apoptosis provides another valuable tool for the investigation of early signaling pathways associated with inducing or delaying PMN apoptosis. J. Leukoc. Biol. 62: 517–523; 1997.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142305/1/jlb0517.pd

    Intrapartum antibiotics for prolonged rupture of membranes at term to prevent Group B Streptococcal sepsis

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    Background: Group B streptococcus (GBS) is the most common cause of neonatal sepsis in United Kingdom (UK). Early onset sepsis (EOS), but not late onset sepsis (LOS) can be prevented by providing intrapartum antibiotic prophylaxis (IAP). In spite of national guidelines since 2003, the incidence of neonatal GBS infections is increasing in UK. Aim: To assess the incidence of culture proven GBS infections before and after a change of practice on antepartum management of GBS in babies <3 months of age, born at Sunderland Royal Hospital between 1st Jan 2008 and 31st December 2017. Setting: Tertiary neonatal unit Study design: Retrospective cohort study Methods: Babies presenting with signs of sepsis from birth up to 3 months of age were included. Data regarding risk factors, intrapartum antibiotic prophylaxis and outcome of babies were collected. Results: 29 cases were identified and presented in two epochs – before and after changing guidelines for antepartum and intrapartum management. There was a statistically significant reduction in EOS rates and no difference in LOS rates

    Reconceptualising medical curriculum design in strategic clinical leadership training for the 21st century physician

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    This chapter provides an insight into the value of tacit knowledge and how this contributes directly to the concept of human factors in the context of multi-disciplinary teamwork. In considering the notion of implicit or intuitive knowledge and how this can be taught in practice, the authors draw on the field of creative praxis as a means of harnessing knowledge from other (often under-acknowledged) signature pedagogies of direct relevance to medical practice. The authors focus on the significance of situational awareness and context of medical and healthcare provision as a means of driving debate around the value of affective domain learning and its role in 21st century physician practice. These are bracketed under the category of non-technical skill acquisition, which is linked heavily, in the published literature to date, with holistically positive patient outcomes

    Anomalous parity asymmetry of the Wilkinson Microwave Anisotropy Probe power spectrum data at low multipoles

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    We have investigated non-Gaussianity of our early Universe by comparing the parity asymmetry of the WMAP power spectrum with simulations. We find that odd-parity preference of the WMAP data (2<= l <=18) is anomalous at 4-in-1000 level. We find it likely that low quadrupole power is part of this parity asymmetry rather than an isolated anomaly. Futher investigation is required to find out whether the origin of this anomaly is cosmological or systematic effect. The data from Planck surveyor, which has systematics distinct from the WMAP, will help us to resolve the origin of the anomalous odd-parity preference.Comment: v5: the title updated to match with the ApJL publicatio

    Faraday Rotation as a diagnostic of Galactic foreground contamination of CMB maps

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    The contribution from the residuals of the foreground can have a significant impact on the temperature maps of the Cosmic Microwave Background (CMB). Mostly, the focus has been on the galactic plane, when foreground cleaning has taken place. However, in this paper, we will investigate the possible foreground contamination, from sources outside the galactic plane in the CMB maps. We will analyze the correlation between the Faraday rotation map and the CMB temperature map. The Faraday rotation map is dependent on the galactic magnetic field, as well as the thermal electron density, and both may contribute to the CMB temperature. We find that the standard deviation for the mean cross correlation deviate from that of simulations at the 99.9% level. Additionally, a comparison between the CMB temperature extrema and the extremum points of the Faraday rotation is also performed, showing a general overlap between the two. Also we find that the CMB Cold Spot is located at an area of strong negative cross correlation, meaning that it may be explained by a galactic origin. Further, we investigate nearby supernova remnants in the galaxy, traced by the galactic radio loops. These super nova remnants are located at high and low galactic latitude, and thus well outside the galactic plane. We find some correlation between the Faraday Rotation and the CMB temperature, at select radio loops. This indicate, that the galactic foregrounds may affect the CMB, at high galactic latitudesComment: 13 pages, 22 figures, 6 table
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