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Cortical cell loss is a core feature of Huntington's disease (HD), beginning many years before clinical motor diagnosis, during the premanifest stage. However, it is unclear how genetic topography relates to cortical cell loss. Here, we explore the biological processes and cell types underlying this relationship and validate these using cell-specific post-mortem data. Eighty premanifest participants on average 15 years from disease onset and 71 controls were included. Using volumetric and diffusion MRI we extracted HD-specific whole brain maps where lower grey matter volume and higher grey matter mean diffusivity, relative to controls, were used as proxies of cortical cell loss. These maps were combined with gene expression data from the Allen Human Brain Atlas (AHBA) to investigate the biological processes relating genetic topography and cortical cell loss. Cortical cell loss was positively correlated with the expression of developmental genes (i.e. higher expression correlated with greater atrophy and increased diffusivity) and negatively correlated with the expression of synaptic and metabolic genes that have been implicated in neurodegeneration. These findings were consistent for diffusion MRI and volumetric HD-specific brain maps. As wild-type huntingtin is known to play a role in neurodevelopment, we explored the association between wild-type huntingtin (HTT) expression and developmental gene expression across the AHBA. Co-expression network analyses in 134 human brains free of neurodegenerative disorders were also performed. HTT expression was correlated with the expression of genes involved in neurodevelopment while co-expression network analyses also revealed that HTT expression was associated with developmental biological processes. Expression weighted cell-type enrichment (EWCE) analyses were used to explore which specific cell types were associated with HD cortical cell loss and these associations were validated using cell specific single nucleus RNAseq (snRNAseq) data from post-mortem HD brains. The developmental transcriptomic profile of cortical cell loss in preHD was enriched in astrocytes and endothelial cells, while the neurodegenerative transcriptomic profile was enriched for neuronal and microglial cells. Astrocyte-specific genes differentially expressed in HD post-mortem brains relative to controls using snRNAseq were enriched in the developmental transcriptomic profile, while neuronal and microglial-specific genes were enriched in the neurodegenerative transcriptomic profile. Our findings suggest that cortical cell loss in preHD may arise from dual pathological processes, emerging as a consequence of neurodevelopmental changes, at the beginning of life, followed by neurodegeneration in adulthood, targeting areas with reduced expression of synaptic and metabolic genes. These events result in age-related cell death across multiple brain cell types. [ABSTRACT FROM AUTHOR]

Structural brain networks may be reconstructed from diffusion MRI tractography data and have great potential to further our understanding of the topological organisation of brain structure in health and disease. Network reconstruction is complex and involves a series of processesing methods including anatomical parcellation, registration, fiber orientation estimation and whole-brain fiber tractography. Methodological choices at each stage can affect the anatomical accuracy and graph theoretical properties of the reconstructed networks, meaning applying different combinations in a network reconstruction pipeline may produce substantially different networks. Furthermore, the choice of which connections are considered important is unclear. In this study, we assessed the similarity between structural networks obtained using two independent state-of-the-art reconstruction pipelines. We aimed to quantify network similarity and identify the core connections emerging most robustly in both pipelines. Similarity of network connections was compared between pipelines employing different atlases by merging parcels to a common and equivalent node scale. We found a high agreement between the networks across a range of fiber density thresholds. In addition, we identified a robust core of highly connected regions coinciding with a peak in similarity across network density thresholds, and replicated these results with atlases at different node scales. The binary network properties of these core connections were similar between pipelines but showed some differences in atlases across node scales. This study demonstrates the utility of applying multiple structural network reconstrution pipelines to diffusion data in order to identify the most important connections for further study. [ABSTRACT FROM AUTHOR]

The author discusses the factors in determining the development of the sickle cell disease (SCD) as well as its history and prevalence in the U.S. He states that the shift of SCD from obscurity in Africa to visibility in the U.S. over a century has been intertwined with race relations and politics unique to the U.S. He also notes the socio-political development of SCD in line to the development of a scientific understanding of the disease and the evolution of disease control strategies.

With its preference for small government and fiscal responsibility, the Tea Party movement claims to be conservative. Yet, their tactics and rhetoric belie this claim. The shrill attacks against Blacks, illegal immigrants, and gay rights are all consistent with conservatism, but suggesting that the president is a socialist bent on ruining the country, is beyond politics. This chapter shows that Richard Hofstadter's thesis about the "paranoid style" of American politics helps characterize the Tea Party's pseudo- conservatism. Through a comprehensive analysis of qualitative interviews, content analysis and public opinion data, we find that Tea Party sympathizers are not mainstream conservatives, but rather, they hold a strong sense of out-group anxiety and a concern over the social and demographic changes in America. [ABSTRACT FROM AUTHOR]

Bleeding and clotting in women is an issue that directly affects the life of every woman, child, and family worldwide. This article summarizes recent activities undertaken by the Division of Blood Disorders (DBD) at the Centers for Disease Control and Prevention (CDC) to identify risk factors through evidence-based research and surveillance to prevent complications of blood disorders in women. Specific focus is given to our efforts to improve early identification and diagnosis of blood disorders among women, improve our understanding of maternal and infant outcomes, and develop surveillance systems to monitor the prevalence and incidence of these events. [ABSTRACT FROM AUTHOR]

Patriotism is an important predictor of political attitudes and preferences. Nevertheless, the complexity of patriotism remains unresolved, especially as it pertains to blind and symbolic patriotism. Symbolic patriotism represents a relatively abstract, affective attachment to the nation and its core values. Blind patriotism, in contrast, is more concrete, indexing uncritical support for national policies and practices. While the concepts appear analytically distinct, their political consequences are often similar, leading one to question whether the distinction is real. The results offer some support for maintaining conceptual differences between blind and symbolic patriotism. [ABSTRACT FROM AUTHOR]

Recent narratives of the civil rights movement document black veterans' contributions to the movement's success, often attributing their efforts to their military experience. While this attribution makes sense intuitively, alternative explanations for black veterans' mobilization are not fully explored in existing work. For instance, black veterans were often among the most active members in many of the civil rights organizations from which insurgency was launched. Therefore, we cannot rule out the possibility that black civic institutions, not military service per se, drove black veterans' activism. Furthermore, if military service did lead to political activism, we lack a microlevel mechanism to explain the means by which it did so. In this article, I show that military service did motivate black veterans' activism independent of their membership in black civic institutions or feelings of group solidarity and theorize a mechanism by which it did so. [ABSTRACT FROM AUTHOR]

Improving the health of our children offers the greatest potential for improving the health of our nation. One paradigm for improving the health of children that may offer the greatest rate of return lies in improving the health of women. Throughout the complete life stages of both women and children, overall good health of women positively influences the health and wellness of our children. [ABSTRACT FROM AUTHOR]

Investigates the consequences of increased arm sales to developing countries. Context in which arms and technology transfers have taken place; Sociological approach to military effectiveness; Covariation of military effectiveness and assimilation; Effects of conventional weapons proliferation to the United States' foreign policy.

The paper suggests that the bridging of the growing university/schools gap (resulting from a growing corpus of theory at research level) may be achieved by the use of various models which act as both teaching aids and conceptual props. In this respect it outlines some of the uses of models in school geography, while concerning itself in more detail with the use of analogue models in human geography. The rules for the valid use of such analogues are reviewed, and illustrated via the medium of a weighted chemical diffusion model to delimit spheres of influence in a given group of settlements. [ABSTRACT FROM PUBLISHER]