Constraints on dark matter and the shape of the Milky Way dark halo from the 511 keV line

About one year ago, it was speculated that decaying or annihilating Light Dark Matter (LDM) particles could explain the flux and extension of the 511 keV line emission in the galactic centre. Here we present a thorough comparison between theoretical expectations of the galactic positron distribution within the LDM scenario and observational data from INTEGRAL/SPI. Unlike previous analyses, there is now enough statistical evidence to put tight constraints on the shape of the dark matter halo of our galaxy, if the galactic positrons originate from dark matter. For annihilating candidates, the best fit to the observed 511 keV emission is provided by a radial density profile with inner logarithmic slope gamma=1.03+-0.04. In contrast, decaying dark matter requires a much steeper density profile, gamma>1.5, rather disfavoured by both observations and numerical simulations. Within the annihilating LDM scenario, a velocity-independent cross-section would be consistent with the observational data while a cross-section purely proportional to v^2 can be rejected at a high confidence level. Assuming the most simplistic model where the galactic positrons are produced as primaries, we show that the LDM candidate should be a scalar rather than a spin-1/2 particle and obtain a very stringent constraint on the value of the positron production cross-section to explain the 511 keV emission. One consequence is that the value of the fine structure constant should differ from that recommended in the CODATA. This is a very strong test for the LDM scenario and an additional motivation in favour of experiments measuring alpha directly. Our results finally indicate that an accurate measurement of the shape of the dark halo profile could have a tremendous impact on the determination of the origin of the 511 keV line and vice versa.Comment: 11 pages, 4 figures, submitted to MNRA

PediDraw: A web-based tool for drawing a pedigree in genetic counseling

<p>Abstract</p> <p>Background</p> <p>Drawing a pedigree is a prerequisite in genetic counseling. In medical records, a pedigree is useful to document the family history of the patient. Drawing a pedigree is also necessary in collecting genetic resources for medical research such as positional cloning. Currently, most pedigrees are drawn by hand or by drawing software. Due to the special requirements in a standardized pedigree, generating a pedigree by these methods is usually time-consuming and requires professionals. This limits the usage of a pedigree as demanded in remote diagnosis or online counseling from the counselees to send an electronic pedigree.</p> <p>Results</p> <p>We developed an online pedigree drawing tool, PediDraw, which enables users to generate pedigrees after inputting the family information step-by-step on web. It outputs a pedigree or table to present a family history to the counselors.</p> <p>Conclusion</p> <p>PediDraw is a user-friendly web-based drawing tool. It is accessible via Internet.</p

Continuity or change in business representation in Britain? An assessment of the Heseltine initiatives of the 1990s

Britain has a fragmented, overlapping, and underresourced system of business representation. Attempts at reform, however, have proved difficult and largely unsuccessful. A coherent and logical system is relevant, in terms of both an effective dialogue between government and business, and the promotion of competitiveness and productivity. Through interviews and archival evidence, I look at how government has attempted to reform business associations. The main focus is the Heseltine initiatives of the 1990s: I outline the various initiatives taken, reveal the extent to which policy represented continuity or change, and consider whether the initiatives were effective. I show that they had a degree of success but that they would have made greater impact if they had been sustained over a longer period of time. A consideration of the historical context, moreover, suggests there may be limits to the role of government intervention in business association reform

Fatal child maltreatment in England, 2005-9

Objective: This paper presents comprehensive and up-to-date data covering four years of Serious Case Reviews into fatal child maltreatment in England. Methods: Information on all notified cases of fatal maltreatment between April 2005 and March 2009 was examined to obtain case characteristics related to a systemic classification of five broad groups of maltreatment deaths (severe physical assaults; covert homicide/infanticide; overt homicide; extreme neglect/deprivational abuse; deaths related to but not directly caused by maltreatment). Results: A total of 276 cases was recorded giving an incidence of 0.63 cases per 100,000 children (0-17) per year. 246 cases could be classified based on the data available. Of these the commonest specific group was those children who died as a result of severe physical assaults. Apparently deliberate overt and covert homicide was less common, whilst deaths as a direct consequence of neglect were rare. In contrast, some evidence of neglect was found in at least 40% of all cases, though not the direct cause of death. Conclusions: Class characteristics differ between the different categories of death and may suggest the need for different strategies for prevention

Physicochemical and biological responses of streams to wildfire severity in riparian zones

We investigated the effects of a wildfire on stream physical, chemical and biological characteristics in a Mediterranean climate, comparing stream community structure and consumer resource use in burned versus unburned catchments in Santa Barbara County, CA, U.S.A. Canopy cover was lower and water temperature was higher in streams draining basins where the riparian vegetation burned than in streams in unburned basins or burned basins where riparian vegetation remained intact. Stream flow and suspended sediment concentrations during large post-fire storms and wet season nutrient levels were higher in burned than unburned catchments, with increased sedimentation after flood peaks. A year after fires, algal levels were highest in streams where riparian vegetation burned and lowest in streams in burned basins where the riparian canopy remained intact. In contrast, streams in burned basins had lower particulate organic matter, detritivore and predator levels than unburned basins, regardless of whether riparian vegetation burned. Where present, southern California steelhead trout (Oncorhynchus mykiss) were extirpated from burned basins. Algivore densities were high in streams with burned riparian vegetation for two post-fire years before declining to unburned stream levels. Shredder densities rebounded in streams in burned basins with intact riparian vegetation, but remained low for 4 years where riparian vegetation burned. Predatory invertebrate densities increased at sites where trout were eliminated by wildfire. Hydrogen stable isotope analysis indicated that the diets of most invertebrate taxa in streams with burned riparian vegetation a year after fires were comprised of a higher proportion of algal material than riparian detritus relative to invertebrates in streams with intact riparian vegetation. Wildfire impacts on stream food webs are determined, in part, by fire severity in the riparian zone. Streams with burned riparian canopies supported algal-based food webs and streams with intact riparian canopies sustained detrital-based food webs. Fire affected basal resources (nutrients, light, allochthonous inputs) with bottom-up effects on primary producers and consumers, but top-down effects were decoupled at the trophic link between invertebrate predators and primary consumers. © 2015 John Wile

The timing of mandibular tooth formation in two African groups

Background: Ethnic differences in the timing of human tooth development are unclear. Aim: To describe similarities and differences in the timing of tooth formation in two groups of Sudanese children and young adults. Subjects and methods: The sample consisted of healthy individuals from Khartoum, Sudan, aged 2–23 years. The Northern group was of Arab origin (848 males, 802 females) and the Western group was of African origin (846 males, 402 females). Each mandibular left permanent tooth from first incisor to third molar was assessed from dental radiographs into one of 15 development stages. Mean ages at entry for 306 tooth stages were calculated using probit regression in males/females in each group and compared using a t-test. Results: Mean ages were not significantly different in most tooth stage comparisons between ethnic groups for both males (61/75) and females (56/76), despite a tendency of earlier mean ages in the Western group. Mean ages for most tooth stage comparisons between males and females (137/155) were not significantly different within ethnic groups suggesting low sexual dimorphism. Conclusion: The mean ages of most mandibular tooth formation stages were generally not significantly different between ethnic groups or between males and females in this study

Is metal theft committed by organized crime groups, and why does it matter?

Using the example of metal theft in the United Kingdom, this study used mixed methods to evaluate the accuracy of police estimates of the involvement of organised crime groups (OCGs) in crime. Police estimate that 20-30% of metal theft is committed by OCGs, but this study found that only 0.5% of metal thieves had previous convictions for offences related to OCGs, that only 1.3% were linked to OCGs by intelligence information, that metal thieves typically offended close to their homes and that almost no metal thefts involved sophisticated offence methods. It appears that police may over-estimate the involvement of OCGs in some types of crime. The reasons for and consequences of this over-estimation are discussed

Using small molecules to facilitate exchange of bicarbonate and chloride anions across liposomal membranes

Bicarbonate is involved in a wide range of biological processes, which include respiration, regulation of intracellular pH and fertilization. In this study we use a combination of NMR spectroscopy and ion-selective electrode techniques to show that the natural product prodigiosin, a tripyrrolic molecule produced by microorganisms such as Streptomyces and Serratia, facilitates chloride/bicarbonate exchange (antiport) across liposomal membranes. Higher concentrations of simple synthetic molecules based on a 4,6-dihydroxyisophthalamide core are also shown to facilitate this antiport process. Although it is well known that proteins regulate Cl-/HCO3- exchange in cells, these results suggest that small molecules may also be able to regulate the concentration of these anions in biological systems

Clonal karyotype evolution involving ring chromosome 1 with myelodysplastic syndrome subtype RAEB-t progressing into acute leukemia

s Karyotypic evolution is a well-known phenomenon in patients with malignant hernatological disorders during disease progression. We describe a 50-year-old male patient who had originally presented with pancytopenia in October 1992. The diagnosis of a myelodysplastic syndrome (MDS) FAB subtype RAEB-t was established in April 1993 by histological bone marrow (BM) examination, and therapy with low-dose cytosine arabinoside was initiated. In a phase of partial hernatological remission, cytogenetic assessment in August 1993 revealed a ring chromosome 1 in 13 of 21 metaphases beside BM cells with normal karyotypes {[}46,XY,r(1)(p35q31)/46,XY]. One month later, the patient progressed to an acute myeloid leukemia (AML), subtype M4 with 40% BM blasts and cytogenetic examination showed clonal evolution by the appearance of additional numerical aberrations in addition to the ring chromosome{[}46,XY,r(1),+8,-21/45,XY,r(1),+8,-21,-22/46, XY]. Intensive chemotherapy and radiotherapy was applied to induce remission in preparation for allogeneic bone marrow transplantation (BMT) from the patient's HLA-compatible son. After BMT, complete remission was clinically, hematologically and cytogenetically (normal male karyotype) confirmed. A complete hematopoietic chimerism was demonstrated. A relapse in January 1997 was successfully treated using donor lymphocyte infusion and donor peripheral blood stem cells (PB-SC) in combination with GM-CSF as immunostimulating agent in April 1997, and the patient's clinical condition remained stable as of January 2005. This is an interesting case of a patient with AML secondary to MDS. With the ring chromosome 1 we also describe a rare cytogenetic abnormality that predicted the poor prognosis of the patient, but the patient could be cured by adoptive immunotherapy and the application of donor's PB-SC. This case confirms the value of cytogenetic analysis in characterizing the malignant clone in hernatological neoplasias, the importance of controlling the quality of an induced remission and of the detection of a progress of the disease. Copyright (c) 2006 S. Karger AG, Basel