579 research outputs found

    Redefining Home: Understanding Congolese Refugee Community Organization in the Greater Boston Area

    Get PDF
    For refugees that have been resettled into hostland nations, the creation of formal refugee community organizations (RCOs) dedicated to assisting immigrants represents a grassroots response to the stresses of migration. Despite their importance to the lives of refugees, RCOs have received little scholarly attention in the United States. Even less attention has been dedicated to studying the role of RCOs for African peoples. This research seeks to address these gaps in scholarship by analyzing community understandings of one RCO, the Congolese Development Center, among the Congolese refugee community located in the North Shore region of Massachusetts. Using qualitative ethnographic data, this research interrogates the interface between the organizational behaviors of the community and the societal structures that impact social organization, including global capitalism, systemic racism, heteropatriarchy, and neoliberal governance pressures. My findings suggest that these systems of marginalization and oppression fragment communities and exert pressure on the individuals and organizations at the bottom of the resettlement chain, replicating inequalities and limiting the ability of refugee communities to address the problems they face

    Transcriptional regulatory networks in the mouse hippocampus

    Get PDF
    Magister Scientiae - MScNeurological diseases are socially disabling and often mortal. To efficiently combat these diseases, a deep understanding of involved cellular processes, gene functions and anatomy is required. However, differential regulation of genes across anatomy is not sufficiently well understood. This study utilized large-scale gene expression data to define the regulatory networks of genes expressing in the hippocampus to which multiple disease pathologies may be associated. Specific aims were: ident i fy key regulatory transcription factors (TFs) responsible for observed gene expression patterns, reconstruct transcription regulatory networks, and prioritize likely TFs responsible for anatomically restricted gene expression. Most of the analysis was restricted to the CA3 sub-region of Ammon’s horn within the hippocampus. We identified 155 core genes expressing throughout the CA3 sub-region and predicted corresponding TF binding site (TFBS) distributions. Our analysis shows plausible transcription regulatory networks for twelve clusters of co-expressed genes. We demonstrate the validity of the predictions by re-clustering genes based on TFBS distributions and found that genes tend to be correctly assigned to groups of previously identified co-expressing genes with sensitivity of 67.74% and positive predictive value of 100%. Taken together, this study represents one of the first to merge anatomical architecture, expression profiles and transcription regulatory potential on such a large scale in hippocampal sub-anatomy.South Afric

    A classification of primitive permutation groups with finite stabilizers

    Get PDF
    We classify all infinite primitive permutation groups possessing a finite point stabilizer, thus extending the seminal Aschbacher-O'Nan-Scott Theorem to all primitive permutation groups with finite point stabilizers.Comment: Accepted in J. Algebra. Various changes, some due to the author, some due to suggestions from readers and others due to the comments of anonymous referee

    Association Between First Attempt Buffalo Concussion Treadmill Test and Days to Recovery in 855 Children With Sport-Related Concussion: A Historical Cohort Study and Prognostic Factors Analysis

    Full text link
    OBJECTIVE: Little is known about the prognostic value of the Buffalo Concussion Treadmill Test (BCTT) after the acute phase of sport-related concussion (SRC). We examined the added prognostic value of the BCTT performed 10 to 21 days after SRC in children, in addition to participant, injury, and clinical process characteristics on days to recovery. DESIGN: Historical clinical cohort study. SETTING: Network of approximately 150 Canadian multidisciplinary primary-care clinics. PARTICIPANTS: 855 children (mean age 14 years, range 6-17 years, 44% female) who presented between January 2016, and April 2019 with SRC. ASSESSMENT OF RISK FACTORS: Participant, injury, and clinical process characteristics, with focus on BCTT exercise intolerance assessed 10 to 21 days after injury. OUTCOME: Days to clinical recovery. RESULTS: Children who were exercise intolerant experienced an increase of 13 days to recovery (95% CI, 9-18 days). Each additional day between SRC and first BCTT was associated with a recovery delay of 1 day (95% CI, 1-2 days), and prior history of concussion was associated with a recovery delay of 3 days (95% CI, 1-5 days). Participant, injury, and clinical process characteristics, and the first attempt BCTT result explained 11% of the variation in recovery time, with 4% accounted for by the BCTT. CONCLUSION: Exercise-intolerance assessed 10 to 21 days after SRC was associated with delayed recovery. However, this was not a strong prognostic factor for days to recovery

    Collineation group as a subgroup of the symmetric group

    Full text link
    Let Ψ\Psi be the projectivization (i.e., the set of one-dimensional vector subspaces) of a vector space of dimension ≥3\ge 3 over a field. Let HH be a closed (in the pointwise convergence topology) subgroup of the permutation group SΨ\mathfrak{S}_{\Psi} of the set Ψ\Psi. Suppose that HH contains the projective group and an arbitrary self-bijection of Ψ\Psi transforming a triple of collinear points to a non-collinear triple. It is well-known from \cite{KantorMcDonough} that if Ψ\Psi is finite then HH contains the alternating subgroup AΨ\mathfrak{A}_{\Psi} of SΨ\mathfrak{S}_{\Psi}. We show in Theorem \ref{density} below that H=SΨH=\mathfrak{S}_{\Psi}, if Ψ\Psi is infinite.Comment: 9 page

    The Supernova Triggered Formation and Enrichment of Our Solar System

    Full text link
    We investigate the enrichment of the pre-solar cloud core with short lived radionuclides (SLRs), especially 26Al. The homogeneity and the surprisingly small spread in the ratio 26Al/27Al observed in the overwhelming majority of calcium-aluminium-rich inclusions (CAIs) in a vast variety of primitive chondritic meteorites places strong constraints on the formation of the the solar system. Freshly synthesized radioactive 26Al has to be included and well mixed within 20kyr. After discussing various scenarios including X-winds, AGB stars and Wolf-Rayet stars, we come to the conclusion that triggering the collapse of a cold cloud core by a nearby supernova is the most promising scenario. We then narrow down the vast parameter space by considering the pre-explosion survivability of such a clump as well as the cross-section necessary for sufficient enrichment. We employ numerical simulations to address the mixing of the radioactively enriched SN gas with the pre-existing gas and the forced collapse within 20kyr. We show that a cold clump of 10Msun at a distance of 5pc can be sufficiently enriched in 26Al and triggered into collapse fast enough - within 18kyr after encountering the supernova shock - for a range of different metallicities and progenitor masses, even if the enriched material is assumed to be distributed homogeneously in the entire supernova bubble. In summary, we envision an environment for the birth place of the Solar System 4.567Gyr ago similar to the situation of the pillars in M16 nowadays, where molecular cloud cores adjacent to an HII region will be hit by a supernova explosion in the future. We show that the triggered collapse and formation of the Solar System as well as the required enrichment with radioactive 26Al are possible in this scenario.Comment: 12 pages, 8 figures, accepted for publication in ApJ. Resolution of most figures degraded to fit within arXiv size limits. A full resolution version is available at http://www.usm.uni-muenchen.de/~gritschm/Gritschneder_2011_sun.pd

    Deciphering the transcriptional circuitry of microRNA genes expressed during human monocytic differentiation

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Macrophages are immune cells involved in various biological processes including host defence, homeostasis, differentiation, and organogenesis. Disruption of macrophage biology has been linked to increased pathogen infection, inflammation and malignant diseases. Differential gene expression observed in monocytic differentiation is primarily regulated by interacting transcription factors (TFs). Current research suggests that microRNAs (miRNAs) degrade and repress translation of mRNA, but also may target genes involved in differentiation. We focus on getting insights into the transcriptional circuitry regulating miRNA genes expressed during monocytic differentiation.</p> <p>Results</p> <p>We computationally analysed the transcriptional circuitry of miRNA genes during monocytic differentiation using <it>in vitro </it>time-course expression data for TFs and miRNAs. A set of TF→miRNA associations was derived from predicted TF binding sites in promoter regions of miRNA genes. Time-lagged expression correlation analysis was utilised to evaluate the TF→miRNA associations. Our analysis identified 12 TFs that potentially play a central role in regulating miRNAs throughout the differentiation process. Six of these 12 TFs (ATF2, E2F3, HOXA4, NFE2L1, SP3, and YY1) have not previously been described to be important for monocytic differentiation. The remaining six TFs are CEBPB, CREB1, ELK1, NFE2L2, RUNX1, and USF2. For several miRNAs (miR-21, miR-155, miR-424, and miR-17-92), we show how their inferred transcriptional regulation impacts monocytic differentiation.</p> <p>Conclusions</p> <p>The study demonstrates that miRNAs and their transcriptional regulatory control are integral molecular mechanisms during differentiation. Furthermore, it is the first study to decipher on a large-scale, how miRNAs are controlled by TFs during human monocytic differentiation. Subsequently, we have identified 12 candidate key controllers of miRNAs during this differentiation process.</p

    Prioritizing genes of potential relevance to diseases affected by sex hormones: an example of Myasthenia Gravis

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>About 5% of western populations are afflicted by autoimmune diseases many of which are affected by sex hormones. Autoimmune diseases are complex and involve many genes. Identifying these disease-associated genes contributes to development of more effective therapies. Also, association studies frequently imply genomic regions that contain disease-associated genes but fall short of pinpointing these genes. The identification of disease-associated genes has always been challenging and to date there is no universal and effective method developed.</p> <p>Results</p> <p>We have developed a method to prioritize disease-associated genes for diseases affected strongly by sex hormones. Our method uses various types of information available for the genes, but no information that directly links genes with the disease. It generates a score for each of the considered genes and ranks genes based on that score. We illustrate our method on early-onset myasthenia gravis (MG) using genes potentially controlled by estrogen and localized in a genomic segment (which contains the MHC and surrounding region) strongly associated with MG. Based on the considered genomic segment 283 genes are ranked for their relevance to MG and responsiveness to estrogen. The top three ranked genes, HLA-G, TAP2 and HLA-DRB1, are implicated in autoimmune diseases, while TAP2 is associated with SNPs characteristic for MG. Within the top 35 prioritized genes our method identifies 90% of the 10 already known MG-associated genes from the considered region without using any information that directly links genes to MG. Among the top eight genes we identified HLA-G and TUBB as new candidates. We show that our <it>ab-initio </it>approach outperforms the other methods for prioritizing disease-associated genes.</p> <p>Conclusion</p> <p>We have developed a method to prioritize disease-associated genes under the potential control of sex hormones. We demonstrate the success of this method by prioritizing the genes localized in the MHC and surrounding region and evaluating the role of these genes as potential candidates for estrogen control as well as MG. We show that our method outperforms the other methods. The method has a potential to be adapted to prioritize genes relevant to other diseases.</p

    Triggering Collapse of the Presolar Dense Cloud Core and Injecting Short-Lived Radioisotopes with a Shock Wave. I. Varied Shock Speeds

    Full text link
    The discovery of decay products of a short-lived radioisotope (SLRI) in the Allende meteorite led to the hypothesis that a supernova shock wave transported freshly synthesized SLRI to the presolar dense cloud core, triggered its self-gravitational collapse, and injected the SLRI into the core. Previous multidimensional numerical calculations of the shock-cloud collision process showed that this hypothesis is plausible when the shock wave and dense cloud core are assumed to remain isothermal at ~10 K, but not when compressional heating to ~1000 K is assumed. Our two-dimensional models (Boss et al. 2008) with the FLASH2.5 adaptive mesh refinement (AMR) hydrodynamics code have shown that a 20 km/sec shock front can simultaneously trigger collapse of a 1 solar mass core and inject shock wave material, provided that cooling by molecular species such as H2O, CO, and H2 is included. Here we present the results for similar calculations with shock speeds ranging from 1 km/sec to 100 km/sec. We find that shock speeds in the range from 5 km/sec to 70 km/sec are able to trigger the collapse of a 2.2 solar mass cloud while simultaneously injecting shock wave material: lower speed shocks do not achieve injection, while higher speed shocks do not trigger sustained collapse. The calculations continue to support the shock-wave trigger hypothesis for the formation of the solar system, though the injection efficiencies in the present models are lower than desired.Comment: 39 pages, 14 figures. in press, Ap
    • …
    corecore