Shuttle/spacelab MMAP/electromagnetic environment experiment phase B definition study

Progress made during the first five months of the Phase B definition study for the MMAP/Electromagnetic Environment Experiment (EEE) was described. An antenna/receiver assembly has been defined and sized for stowing in a three pallet bay area in the shuttle. Six scanning modes for the assembly are analyzed and footprints for various antenna sizes are plotted. Mission profiles have been outlined for a 400 km height, 57 deg inclination angle, circular orbit. Viewing time over 7 geographical areas are listed. Shuttle interfaces have been studied to determine what configuration the antenna assembly must have to be shared with other experiments of the Microwave Multi-Applications Payload (MMAP) and to be stowed in the shuttle bay. Other results reported include a frequency plan, a proposed antenna subsystem design, a proposed receiver design, preliminary outlines of the experiment controls and an analysis of on-board and ground data processing schemes

Light except Lupita: The representation of Black women in magazines

Psychology is dominated by White Westerners. Subsequently researchers have minimised or ignored Black women’s body dissatisfaction. This study sought to account for the intersection of racism and body dissatisfaction by coding the representation of Black women, the number of appearance adverts and articles across 8 issues of mainstream women’s magazines (Elle, Vogue) and Black women’s magazines (Essence and Ebony) from 2015/16. The majority of Black women featured in the magazines (N = 539) were young (83 per cent) slim (62 per cent), had light skin (66 per cent) and straight hair (60 per cent). Compared to the Black women’s magazines, Black women were rarely represented in the mainstream women’s magazines (N = 64, 11 per cent) and when they were represented generally had straighter hair, narrow noses and lighter skin tones. This study underscores the need for psychology, including body dissatisfaction researchers, to recognise (and challenge) the intersections of racism with other impacts to wellbeing including body dissatisfaction

The Mechanical Properties of Fresh and Cryopreserved Arterial Homografts

AbstractObjectives to assess the effect of cryopreservation on the elasticity and compliance of arterial allografts. Materials and methods iliofemoral segments of arteries and veins harvested from multiorgan donors were divided into two groups: fresh–control, tested for 24 hours after harvesting, and cryopreserved in liquid nitrogen after pretreatment with 20% dimethylsulphoxide and stored for an average time of 22 days. Vessel wall elastic properties were evaluated from the stress–strain relationship in a specially designed test cell fixed to the Instron Universal Testing Machine. Results the elastic modulus of the artery control group (1.54±0.33 MPa, n=20) was not significantly different from the cryopreserved group (1.69±0.61 MPa, n=15). Similarly, values for unfrozen veins (3.11±0.65 MPa, n=47) were not significantly different from those of frozen samples (2.71±0.85 MPa, n=38). Control compliance (6.86±1.79×10−5%/Pa, for arteries; 3.84±0.81×10−5%/Pa, for veins) was similar to that of the cryopreserved group (6.66±1.80×10−5%/Pa, for arteries; 4.16±1.21×10−5%/Pa, for veins). Conclusions cryopreservation maintains the important elastic properties of arterial and venous allografts during average storage time of 22 days

Young men’s minimisation of their body dissatisfaction

Objective: To examine men’s body dissatisfaction qualitatively. Design: Forty-two British men aged 18–45 years took part in a two-session group intervention across 12 groups. The intervention was designed to improve body dissatisfaction by engaging them in a critique of the appearance ideal through written and behavioural exercises. Main outcome measures/results: Analysis of the topics discussed during the intervention generated two core themes. Theme 1 showed that, in general, men minimised the existence of their own body dissatisfaction while (somewhat surprisingly) outlining the ubiquity and potency of the appearance ideal for men in general. Theme 2 involved men reporting the problematic impact of body dissatisfaction in their lives (despite earlier minimisation), such as social avoidance, strict eating and supplement regimes, or difficulty in situations where the body was exposed. Conclusion: The results stress the need to acknowledge that men experience a range of impacts of body dissatisfaction beyond clinical presentations (such as disordered eating) that influence their everyday lives, while also recognising that they tend to minimise this dissatisfaction in conversation. These findings have important implications for advocacy and interventions to improve men’s body dissatisfaction

"Peeling property" for linearized gravity in null coordinates

A complete description of the linearized gravitational field on a flat background is given in terms of gauge-independent quasilocal quantities. This is an extension of the results from gr-qc/9801068. Asymptotic spherical quasilocal parameterization of the Weyl field and its relation with Einstein equations is presented. The field equations are equivalent to the wave equation. A generalization for Schwarzschild background is developed and the axial part of gravitational field is fully analyzed. In the case of axial degree of freedom for linearized gravitational field the corresponding generalization of the d'Alembert operator is a Regge-Wheeler equation. Finally, the asymptotics at null infinity is investigated and strong peeling property for axial waves is proved.Comment: 27 page

A New 5-Flavour LO Analysis and Parametrization of Parton Distributions in the Real Photon

New, radiatively generated, LO quark (u,d,s,c,b) and gluon densities in a real, unpolarized photon are presented. We perform a global 3-parameter fit, based on LO DGLAP evolution equations, to all available data for the structure function F2^gamma(x,Q^2). We adopt a new theoretical approach called ACOT(chi), originally introduced for the proton, to deal with the heavy-quark thresholds. This defines our basic model (CJKL model), which gives a very good description of the experimental data on F2^gamma(x,Q^2), for both Q^2 and x dependences. For comparison we perform a standard fit using the Fixed Flavour-Number Scheme (FFNS_CJKL model), updated with respect to the previous fits of this type. We show the superiority of the CJKL fit over the FFNS_CJKL one and other LO fits to the F2^gamma(x,Q^2) data. The CJKL model gives also the best description of the LEP data on the Q^2 dependence of the F2^gamma, averaged over various x-regions, and the F_2,c^gamma, which were not used directly in the fit. Finally, a simple analytic parametrization of the resulting parton densities obtained with the CJKL model is given.Comment: 43 pages, RevTeX4 using axodraw style, 3 tex and 12 postscript figures, version submitted to Phys. Rev. D, small text changes, one reference added, FORTRAN program available at http://www.fuw.edu.pl/~pjank/param.html and at http://www-zeuthen.desy.de/~alorca/id4.htm

Disordered clock protein interactions and charge blocks turn an hourglass into a persistent circadian oscillator

Organismal physiology is widely regulated by the molecular circadian clock, a feedback loop composed of protein complexes whose members are enriched in intrinsically disordered regions. These regions can mediate protein-protein interactions via SLiMs, but the contribution of these disordered regions to clock protein interactions had not been elucidated. To determine the functionality of these disordered regions, we applied a synthetic peptide microarray approach to the disordered clock protein FRQ in Neurospora crassa. We identified residues required for FRQ\u27s interaction with its partner protein FRH, the mutation of which demonstrated FRH is necessary for persistent clock oscillations but not repression of transcriptional activity. Additionally, the microarray demonstrated an enrichment of FRH binding to FRQ peptides with a net positive charge. We found that positively charged residues occurred in significant blocks within the amino acid sequence of FRQ and that ablation of one of these blocks affected both core clock timing and physiological clock output. Finally, we found positive charge clusters were a commonly shared molecular feature in repressive circadian clock proteins. Overall, our study suggests a mechanistic purpose for positive charge blocks and yielded insights into repressive arm protein roles in clock function

Individual crypt genetic heterogeneity and the origin of metaplastic glandular epithelium in human Barrett’s oesophagus

OBJECTIVES: Current models of clonal expansion in human Barrett's oesophagus are based upon heterogenous, flow-purified biopsy analysis taken at multiple segment levels. Detection of identical mutation fingerprints from these biopsy samples led to the proposal that a mutated clone with a selective advantage can clonally expand to fill an entire Barrett's segment at the expense of competing clones (selective sweep to fixation model). We aimed to assess clonality at a much higher resolution by microdissecting and genetically analysing individual crypts. The histogenesis of Barrett's metaplasia and neo-squamous islands has never been demonstrated. We investigated the oesophageal gland squamous ducts as the source of both epithelial sub-types. METHODS: Individual crypts across Barrett's biopsy and oesophagectomy blocks were dissected. Determination of tumour suppressor gene loss of heterozygosity patterns, p16 and p53 point mutations were carried out on a crypt-by-crypt basis. Cases of contiguous neo-squamous islands and columnar metaplasia with oesophageal squamous ducts were identified. Tissues were isolated by laser capture microdissection and genetically analysed. RESULTS: Individual crypt dissection revealed mutation patterns that were masked in whole biopsy analysis. Dissection across oesophagectomy specimens demonstrated marked clonal heterogeneity, with multiple independent clones present. We identified a p16 point mutation arising in the squamous epithelium of the oesophageal gland duct, which was also present in a contiguous metaplastic crypt, whereas neo-squamous islands arising from squamous ducts were wild-type with respect to surrounding Barrett's dysplasia. CONCLUSIONS: By studying clonality at the crypt level we demonstrate that Barrett's heterogeneity arises from multiple independent clones, in contrast to the selective sweep to fixation model of clonal expansion previously described. We suggest that the squamous gland ducts situated throughout the oesophagus are the source of a progenitor cell that may be susceptible to gene mutation resulting in conversion to Barrett's metaplastic epithelium. Additionally, these data suggest that wild-type ducts may be the source of neo-squamous islands