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Detecting Dark Matter annihilation lines with Fermi
Dark matter constitutes one of the most intriguing but so far unresolved issues in physics today. In many extensions of the Standard Model the existence of a stable Weakly Interacting Massive Particle (WIMP) is predicted. The WIMP is an excellent dark matter particle candidate and one of the most interesting scenarios include an annihilation of two WIMPs into two gamma-rays. If the WIMPs are assumed to be non-relativistic, the resulting photons will both have an energy equal to the mass of the WIMP and manifest themselves as a monochromatic spectral line in the energy spectrum. This type of signal would represent a 'smoking gun' for dark matter, since no other known astrophysical process should be able to produce it. In these proceedings we give an overview of the different approaches to a search for dark matter lines that the Fermi-LAT collaboration is pursuing and the various challenges involved
Reducing Asymmetries in Intergenerational Justice: Descent from Modernity or Space Industrialization?
Normally, contractual conceptions of intergenerational justice regard the responsibility held by each generation as symmetrical. This article argues that the late modern society has created an asymmetry because of its unprecendented instrumental and destructive capacity. Historically unique risks such as thermonuclear destruction, global ecological deprivation, and resource depletion all point at this asymmetry and unequal distribution of responsibility between generations. Extending one contractual device used by John Rawls in line with what Brian Barry has suggested, this article analyzes the roots of the asymmetry and presents two political strategies to end it. The first strategy resembles the traditional deep ecological programme whereas the second holds an imaginative vision of a human future in space. Both strategies seek to reduce the influence present generations exercise on the level of opportunity available to future generations. The key normative argument is that intergenerational justice requires spatial and temporal limits on political action
The private military industry and neoliberal imperialism: Mapping the terrain
Despite the international reach, and increasing global importance, of the free market provision of military and security services—which we label the Private Security Industry (PSI)—management and organization studies has yet to pay significant attention to this industry. Taking up Grey’s (2009) call for scholarship at the boundaries between security studies and organization studies and building on Banerjee’s (2008) treatment of the PSI as a key element in necrocapitalism, in this article we aim to trace the long history of the PSI and argue that it has re-emerged over the last two decades against, and as a result of, a very specific politico-economic backdrop. We then suggest that the PSI operates as a mechanism for neoliberal imperialism; demonstrate its substitution for and supplementing of the state; and count some of the costs of this privatization of war. Finally, we take seriously Hughes’s (2007) thesis of the growth of a new security-industrial complex, and of the intersecting elites who benefit from this phenomenon
Robust physical methods that enrich genomic regions identical by descent for linkage studies: confirmation of a locus for osteogenesis imperfecta
<p>Abstract</p> <p>Background</p> <p>The monogenic disease osteogenesis imperfecta (OI) is due to single mutations in either of the collagen genes ColA1 or ColA2, but within the same family a given mutation is accompanied by a wide range of disease severity. Although this phenotypic variability implies the existence of modifier gene variants, genome wide scanning of DNA from OI patients has not been reported. Promising genome wide marker-independent physical methods for identifying disease-related loci have lacked robustness for widespread applicability. Therefore we sought to improve these methods and demonstrate their performance to identify known and novel loci relevant to OI.</p> <p>Results</p> <p>We have improved methods for enriching regions of identity-by-descent (IBD) shared between related, afflicted individuals. The extent of enrichment exceeds 10- to 50-fold for some loci. The efficiency of the new process is shown by confirmation of the identification of the Col1A2 locus in osteogenesis imperfecta patients from Amish families. Moreover the analysis revealed additional candidate linkage loci that may harbour modifier genes for OI; a locus on chromosome 1q includes COX-2, a gene implicated in osteogenesis.</p> <p>Conclusion</p> <p>Technology for physical enrichment of IBD loci is now robust and applicable for finding genes for monogenic diseases and genes for complex diseases. The data support the further investigation of genetic loci other than collagen gene loci to identify genes affecting the clinical expression of osteogenesis imperfecta. The discrimination of IBD mapping will be enhanced when the IBD enrichment procedure is coupled with deep resequencing.</p
Muscle wasting and the temporal gene expression pattern in a novel rat intensive care unit model
<p>Abstract</p> <p>Background</p> <p>Acute quadriplegic myopathy (AQM) or critical illness myopathy (CIM) is frequently observed in intensive care unit (ICU) patients. To elucidate duration-dependent effects of the ICU intervention on molecular and functional networks that control the muscle wasting and weakness associated with AQM, a gene expression profile was analyzed at time points varying from 6 hours to 14 days in a unique experimental rat model mimicking ICU conditions, i.e., post-synaptically paralyzed, mechanically ventilated and extensively monitored animals.</p> <p>Results</p> <p>During the observation period, 1583 genes were significantly up- or down-regulated by factors of two or greater. A significant temporal gene expression pattern was constructed at short (6 h-4 days), intermediate (5-8 days) and long (9-14 days) durations. A striking early and maintained up-regulation (6 h-14d) of muscle atrogenes (muscle ring-finger 1/tripartite motif-containing 63 and F-box protein 32/atrogin-1) was observed, followed by an up-regulation of the proteolytic systems at intermediate and long durations (5-14d). Oxidative stress response genes and genes that take part in amino acid catabolism, cell cycle arrest, apoptosis, muscle development, and protein synthesis together with myogenic factors were significantly up-regulated from 5 to 14 days. At 9-14 d, genes involved in immune response and the caspase cascade were up-regulated. At 5-14d, genes related to contractile (myosin heavy chain and myosin binding protein C), regulatory (troponin, tropomyosin), developmental, caveolin-3, extracellular matrix, glycolysis/gluconeogenesis, cytoskeleton/sarcomere regulation and mitochondrial proteins were down-regulated. An activation of genes related to muscle growth and new muscle fiber formation (increase of myogenic factors and JunB and down-regulation of myostatin) and up-regulation of genes that code protein synthesis and translation factors were found from 5 to 14 days.</p> <p>Conclusions</p> <p>Novel temporal patterns of gene expression have been uncovered, suggesting a unique, coordinated and highly complex mechanism underlying the muscle wasting associated with AQM in ICU patients and providing new target genes and avenues for intervention studies.</p
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