Tectonic evolution of Lavinia Planitia, Venus

High resolution radar images from the Magellan spacecraft have revealed the first details of the morphology of the Lavinia Planitia region of Venus. Lavinia is a broad lowland over 2000 km across, centered at about 45 deg S latitude, 345 deg E longitude. Herein, the tectonic evolution of Lavinia is discussed, and its possible relationship to processes operating in the planet's interior. The discussion is restricted to the region from 37.3 to 52.6 deg S latitude and from about 340 to 0 deg E longitude. One of the most interesting characteristics of Lavinia is that the entire region possesses a regional tectonic framework of striking regularity. Lavinia is also transected by a complex pattern of belts of intense tectonic deformation known as ridge belts. Despite the gross topographic similarity of all of the ridge belts in Lavinia, they exhibit two rather distinct styles of near surface deformation. One is composed of sets of broad, arch-like ridges rising above the surrounding plains. In the other type, obvious fold-like ridges are rare to absent in the radar images. Both type show evidence for small amounts of shear distributed across the belts

Blood, donors and dollars: Rethinking financial sustainability of safe blood services in Tanzania

Introduction: Collection, processing and distribution of safe blood in Tanzania occurs within a free-for-service context, that is, a collection from non-remunerated blood donors and distributing freely to the needy people through health facilities. The safe blood services in the country appear to be crippled with many challenges and cannot meet the demand for blood and its products. As such, a need for rethinking collection methods, financial models and possible mechanisms for donor remuneration is evident. Methods: In this paper, we venture on multi-stakeholder meetings and ongoing discussions regarding the internal mechanisms of safe blood transfusion financing. The intent is to offer a perspective on the considerations for self-sustaining safe blood services in the country and the extent to which they may be implemented or not. Results: We suggest that despite huge demand, the external donor dependent financing mechanisms for safe blood services in the country are ineffective. Therefore, we discuss two potential ‘internal’ financing mechanisms that have been identified in recent shareholders forums 1) introducing a blood processing fee accompanied by policy change to allow direct charging of either recipients or hospitals or 2) influencing the introduction of ‘blood services’ within the current insurance schemes. Conclusion: We conclude that there is a need for constructing alternative financial mechanisms to sustain the demand of safe blood in the country. We discuss two cost recovery mechanisms, blood processing fee and insurance schemes; however, warning is noted that their implementation warrants structural adjustments, massive community sensitization and optimum stakeholder engagement to maximize acceptability within the country

Intensity Inhomogeneity Correction of SD-OCT Data Using Macular Flatspace

Images of the retina acquired using optical coherence tomography (OCT) often suffer from intensity inhomogeneity problems that degrade both the quality of the images and the performance of automated algorithms utilized to measure structural changes. This intensity variation has many causes, including off-axis acquisition, signal attenuation, multi-frame averaging, and vignetting, making it difficult to correct the data in a fundamental way. This paper presents a method for inhomogeneity correction by acting to reduce the variability of intensities within each layer. In particular, the N3 algorithm, which is popular in neuroimage analysis, is adapted to work for OCT data. N3 works by sharpening the intensity histogram, which reduces the variation of intensities within different classes. To apply it here, the data are first converted to a standardized space called macular flat space (MFS). MFS allows the intensities within each layer to be more easily normalized by removing the natural curvature of the retina. N3 is then run on the MFS data using a modified smoothing model, which improves the efficiency of the original algorithm. We show that our method more accurately corrects gain fields on synthetic OCT data when compared to running N3 on non-flattened data. It also reduces the overall variability of the intensities within each layer, without sacrificing contrast between layers, and improves the performance of registration between OCT images

Seeing red over black and white: popular and media representations of inter-racial relationships as precursors to racial violence

The recent murder in the UK of Anthony Walker attests to the lingering antipathy, indeed hostility, toward intimate inter-racial relationships, especially those involving black men and white women. Seventeen year-old Walker was brutally beaten then fatally assaulted with an axe to his head - the 'provocation' for the attack was this young black man’s relationship with his white girl friend. This paper assesses the historical and contemporary images and mythologies that continue to stigmatize inter-racial relationships. Specifically, we look at the representations disseminated through varied popular media forms. The paper suggests that these mediated constructs condition an environment that facilitates, if not encourages, violence against those in inter-racial relationships

Doing the Work -- Collectively Pursuing Anti-Racist and Equitable Teaching: One High School English Department’s Journey

Our district has long been heralded as a beacon school, one that delivers exceptional education in an exceptional community. Peeling back the layers, however, revealed a district that lurched towards the traditional, even with the hiring of DEI faculty and the step away from an historical indigenous mascot. In a time where teachers are exhausted and afraid of community backlash, our English department dared to tear off the scabs of old wounds and united to push toward what is best for our changing community and students. Hard conversations, difficult topics, and months of legwork at last successfully provided the impetus to move our department forward. As we dug into our curriculum and dug out of our individual comfort zones and passion projects, we realized that we had a long way to go to truly provide an education for our students that was representative of the students in the room and inclusive of all. Haltingly, we began to revamp our curriculum and unite in our goals. Along the way, we found ways to build bridges between old and new staff members, and ultimately joined together to write this article to submit for publication. This article unpacks our individual and collective journeys toward cohesion and inclusion, outlines our inquiry work to “stretch the field of literacy, language arts, and English” in our district, discusses the “tensions [that we] see in literacy education today,” and details our work to “best meet the needs of [our] students” (Language Arts Journal of Michigan, 2021). The work has been and continues to be difficult, but it is critically important—and worth it

Thymic plasmacytoid dendritic cells are susceptible to productive HIV-1 infection and efficiently transfer R5 HIV-1 to thymocytes in vitro

<p>Abstract</p> <p>Background</p> <p>HIV-1 infection of the thymus contributes to the defective regeneration and loss of CD4⁺T cells in HIV-1-infected individuals. As thymic dendritic cells (DC) are permissive to infection by HIV-1, we examined the ability of thymic DC to enhance infection of thymocytes which may contribute to the overall depletion of CD4⁺T cells. We compared productive infection in isolated human thymic and blood CD11c⁺myeloid DC (mDC) and CD123⁺plasmacytoid DC (pDC) using enhanced green fluorescent protein (EGFP) CCR5 (R5)-tropic NL(AD8) and CXCR4 (X4)-tropic NL4-3 HIV-1 reporter viruses. Transfer of productive HIV-1 infection from thymic mDC and pDC was determined by culturing these DC subsets either alone or with sorted thymocytes.</p> <p>Results</p> <p>Productive infection was observed in both thymic pDC and mDC following exposure to R5 HIV-1 and X4 HIV-1. Thymic pDC were more frequently productively infected by both R5 and X4 HIV-1 than thymic mDC (p = 0.03; n = 6). Thymic pDC efficiently transferred productive R5 HIV-1 infection to both CD3^hi(p = 0.01; mean fold increase of 6.5; n = 6) and CD3^lothymocytes (mean fold increase of 1.6; n = 2). In comparison, transfer of productive infection by thymic mDC was not observed for either X4 or R5 HIV-1.</p> <p>Conclusions</p> <p>The capacity of thymic pDC to efficiently transfer R5 HIV-1 to both mature and immature thymocytes that are otherwise refractory to R5 virus may represent a pathway to early infection and impaired production of thymocytes and CD4⁺T cells in HIV-1-infected individuals.</p

Human Immunodeficiency Virus (HIV)-Infected CCR6+ Rectal CD4+ T Cells and HIV Persistence On Antiretroviral Therapy.

BackgroundIdentifying where human immunodeficiency virus (HIV) persists in people living with HIV and receiving antiretroviral therapy is critical to develop cure strategies. We assessed the relationship of HIV persistence to expression of chemokine receptors and their chemokines in blood (n = 48) and in rectal (n = 20) and lymph node (LN; n = 8) tissue collected from people living with HIV who were receiving suppressive antiretroviral therapy.MethodsCell-associated integrated HIV DNA, unspliced HIV RNA, and chemokine messenger RNA were quantified by quantitative polymerase chain reaction. Chemokine receptor expression on CD4+ T cells was determined using flow cytometry.ResultsIntegrated HIV DNA levels in CD4+ T cells, CCR6+CXCR3+ memory CD4+ T-cell frequency, and CCL20 expression (ligand for CCR6) were highest in rectal tissue, where HIV-infected CCR6+ T cells accounted for nearly all infected cells (median, 89.7%). Conversely in LN tissue, CCR6+ T cells were infrequent, and there was a statistically significant association of cell-associated HIV DNA and RNA with CCL19, CCL21, and CXCL13 chemokines.ConclusionsHIV-infected CCR6+ CD4+ T cells accounted for the majority of infected cells in rectal tissue. The different relationships between HIV persistence and T-cell subsets and chemokines in rectal and LN tissue suggest that different tissue-specific strategies may be required to eliminate HIV persistence and that assessment of biomarkers for HIV persistence may not be generalizable between blood and other tissues

Evaluation of real-world mobility in age-related macular degeneration.

BACKGROUND: Previous research has suggested an association between poor vision and decreased mobility, including restricted levels of physical activity and travel away from home. We sought to determine the impact of age-related macular degeneration (AMD) on these measures of mobility. METHODS: Fifty-seven AMD patients with bilateral, or severe unilateral, visual impairment were compared to 59 controls with normal vision. All study subjects were between the ages of 60 and 80. Subjects wore accelerometers and cellular network-based tracking devices over 7 days of normal activity. Number of steps taken, time spent in moderate-to-vigorous physical activity (MVPA), number of excursions from home, and time spent away from home were the primary outcome measures. RESULTS: In multivariate negative binomial regression models adjusted for age, gender, race, comorbidities, and education, AMD participants took fewer steps than controls (18% fewer steps per day, p = 0.01) and spent significantly less time in MVPA (35% fewer minutes, p \u3c 0.001). In multivariate logistic regression models adjusting for age, sex, race, cognition, comorbidities, and grip strength, AMD subjects showed an increased likelihood of not leaving their home on a given day (odds ratio = 1.36, p = 0.04), but did not show a significant difference in the magnitude of time spent away from home (9% fewer minutes, p = 0.11). CONCLUSION: AMD patients with poorer vision engage in significantly less physical activity and take fewer excursions away from the home. Further studies identifying the factors mediating the relationship between vision loss and mobility are needed to better understand how to improve mobility among AMD patients