Very Cold Gas and Dark Matter

We have recently proposed a new candidate for baryonic dark matter: very cold molecular gas, in near-isothermal equilibrium with the cosmic background radiation at 2.73 K. The cold gas, of quasi-primordial abundances, is condensed in a fractal structure, resembling the hierarchical structure of the detected interstellar medium. We present some perspectives of detecting this very cold gas, either directly or indirectly. The H$_2$ molecule has an "ultrafine" structure, due to the interaction between the rotation-induced magnetic moment and the nuclear spins. But the lines fall in the km domain, and are very weak. The best opportunity might be the UV absorption of H$_2$ in front of quasars. The unexpected cold dust component, revealed by the COBE/FIRAS submillimetric results, could also be due to this very cold H$_2$ gas, through collision-induced radiation, or solid H$_2$ grains or snowflakes. The $\gamma$-ray distribution, much more radially extended than the supernovae at the origin of cosmic rays acceleration, also points towards and extended gas distribution.Comment: 16 pages, Latex pages, crckapb macro, 3 postscript figures, uuencoded compressed tar file. To be published in the proceeedings of the "Dust-Morphology" conference, Johannesburg, 22-26 January, 1996, D. Block (ed.), (Kluwer Dordrecht

Elusive Copy Number Variation in the Mouse Genome

Array comparative genomic hybridization (aCGH) to detect copy number variants (CNVs) in mammalian genomes has led to a growing awareness of the potential importance of this category of sequence variation as a cause of phenotypic variation. Yet there are large discrepancies between studies, so that the extent of the genome affected by CNVs is unknown. We combined molecular and aCGH analyses of CNVs in inbred mouse strains to investigate this question.Using a 2.1 million probe array we identified 1,477 deletions and 499 gains in 7 inbred mouse strains. Molecular characterization indicated that approximately one third of the CNVs detected by the array were false positives and we estimate the false negative rate to be more than 50%. We show that low concordance between studies is largely due to the molecular nature of CNVs, many of which consist of a series of smaller deletions and gains interspersed by regions where the DNA copy number is normal.Our results indicate that CNVs detected by arrays may be the coincidental co-localization of smaller CNVs, whose presence is more likely to perturb an aCGH hybridization profile than the effect of an isolated, small, copy number alteration. Our findings help explain the hitherto unexplored discrepancies between array-based studies of copy number variation in the mouse genome

Statistical significance of cis-regulatory modules

BACKGROUND: It is becoming increasingly important for researchers to be able to scan through large genomic regions for transcription factor binding sites or clusters of binding sites forming cis-regulatory modules. Correspondingly, there has been a push to develop algorithms for the rapid detection and assessment of cis-regulatory modules. While various algorithms for this purpose have been introduced, most are not well suited for rapid, genome scale scanning. RESULTS: We introduce methods designed for the detection and statistical evaluation of cis-regulatory modules, modeled as either clusters of individual binding sites or as combinations of sites with constrained organization. In order to determine the statistical significance of module sites, we first need a method to determine the statistical significance of single transcription factor binding site matches. We introduce a straightforward method of estimating the statistical significance of single site matches using a database of known promoters to produce data structures that can be used to estimate p-values for binding site matches. We next introduce a technique to calculate the statistical significance of the arrangement of binding sites within a module using a max-gap model. If the module scanned for has defined organizational parameters, the probability of the module is corrected to account for organizational constraints. The statistical significance of single site matches and the architecture of sites within the module can be combined to provide an overall estimation of statistical significance of cis-regulatory module sites. CONCLUSION: The methods introduced in this paper allow for the detection and statistical evaluation of single transcription factor binding sites and cis-regulatory modules. The features described are implemented in the Search Tool for Occurrences of Regulatory Motifs (STORM) and MODSTORM software

A systematic review of intervention effects on potential mediators of children\u27s physical activity

Background : Many interventions aiming to increase children’s physical activity have been developed and implemented in a variety of settings, and these interventions have previously been reviewed; however the focus of these reviews tends to be on the intervention effects on physical activity outcomes without consideration of the reasons and pathways leading to intervention success or otherwise. To systematically review the efficacy of physical activity interventions targeting 5-12 year old children on potential mediators and, where possible, to calculate the size of the intervention effect on the potential mediator. Methods : A systematic search identified intervention studies that reported outcomes on potential mediators of physical activity among 5-12 year old children. Original research articles published between 1985 and April 2012 were reviewed. Results : Eighteen potential mediators were identified from 31 studies. Positive effects on cognitive/psychological potential mediators were reported in 15 out of 31 studies. Positive effects on social environmental potential mediators were reported in three out of seven studies, and no effects on the physical environment were reported. Although no studies were identified that performed a mediating analysis, 33 positive intervention effects were found on targeted potential mediators (with effect sizes ranging from small to large) and 73% of the time a positive effect on the physical activity outcome was reported. Conclusions : Many studies have reported null intervention effects on potential mediators of children’s physical activity; however, it is important that intervention studies statistically examine the mediating effects of interventions so the most effective strategies can be implemented in future programs

Foreign policy and globalization theory: The case of Israel

Since the early 1990s, international relations has witnessed a stimulating debate on globalization. This debate laid the foundations for globalization theory (GT), providing the tools for an empirical examination of the globalization of multiple activities: from politics and organized violence, to finance, trade and production, through culture and environmental degradation. However, examination of what appear to be the best-known works on globalization reveals that foreign policy has been virtually excluded from GT. In this context, based on what is described here as a synergistic transformationalist approach (STA) to globalization, I provide a critique of GT. The critique is geared towards examining why foreign policy hitherto has been overlooked by contemporary GT. I expose the problems this generates and address them by exploring how STA enables GT to incorporate foreign policy. I use the case of Israel heuristically to elicit how incorporating foreign policy into GT may provide a better understanding of the relationship between foreign policy and globalization. Three themes are highlighted: the role of foreign policy in inducing and reproducing globalization; determining the mutually constitutive relationship between globalization and the state; and shaping the interfacing between international politics and globalization

Rinoplastia do nariz negróide por via intra-oral sem ressecções externas: avaliação da eficácia da técnica Negroid nose's rinoplasty through intra-oral approach without external excisions: evaluation of the efficiency of the technique

OBJETIVO: Avaliar a eficácia da técnica de redução da largura da base nasal do nariz negróide, modificando a inclinação dos eixos das narinas pela mobilização de tecidos internos, por abordagem intra-oral, evitando cicatrizes externas. MÉTODOS: Foram operadas 11 pacientes adulta do sexo feminino, com idade variando entre 19 a 45 anos, distribuindo-se em 2 da raça caucasóide e 9 da raça negróide, sendo desta 5 de cor parda e 4 de cor negra. O método de fotografia foi padronizado, e as imagens em papel foram digitalizadas. Por meio de software foram mensurados nas fotografias pré-operatórias e com 3 meses após a rinoplastia, 8 índices relativos à base nasal baseados em pontos antropométricos. Os valores obtidos foram submetidos à análise estatística descritiva e inferencial. RESULTADOS: Não houve diferença estatisticamente significante em 7 índices relativos a redução da largura da base nasal e à inclinação dos eixos das narinas. Apenas houve alteração significante no aumento do Ângulo Nasolabial (p=0,001). CONCLUSÃO: A técnica de rinoplastia de nariz negróide por via intra-oral sem ressecções externas, apenas com mobilização dos tecidos internos, não é eficaz para a reduzir a largura da base nasal.<br>OBJECTIVE: To evaluate effectiveness of the technique of reduction of the width of the nasal base of negroid nose, modifying the inclination of the axes of the nostrils for the mobilization of internal tissues, through intra-oral approach, avoiding external scars. METHODS: Eleven adult female patients were operated with age varying between 19 to 45 years old, being distributed in 2 of the Caucasoid race and 9 of negroid race, being of this 5 brown color and 4 of black color. The picture method was standardized, and images in paper were digitized. Through software they were measured in the pre-operative pictures and with 3 months after the rhinoplasty. 8 relative indexes to the nasal base based on anthropometrics points. The obtained values were submitted to statistically descriptive analysis. RESULTS: No significant statistically differences were found in seven of these features, relative reduction of the width of the nasal base and the variation in the axis of the nostrils inclinations. Just one significant alteration found, an increased in the nasal labial angle (p=0,001). CONCLUSION: The technique of rhinoplasty of negroid nose through intra-oral approach without external resection, just with mobilization of the internal tissues is not effective to reduce the nasal base