Phased Array Feed Calibration, Beamforming and Imaging

Phased array feeds (PAFs) for reflector antennas offer the potential for increased reflector field of view and faster survey speeds. To address some of the development challenges that remain for scientifically useful PAFs, including calibration and beamforming algorithms, sensitivity optimization, and demonstration of wide field of view imaging, we report experimental results from a 19 element room temperature L-band PAF mounted on the Green Bank 20-Meter Telescope. Formed beams achieved an aperture efficiency of 69% and system noise temperature of 66 K. Radio camera images of several sky regions are presented. We investigate the noise performance and sensitivity of the system as a function of elevation angle with statistically optimal beamforming and demonstrate cancelation of radio frequency interference sources with adaptive spatial filtering.Comment: 19 pages, 13 figure

Bird Strike Mitigation, Spring 2021

Bird Strike Migration Project for Sustainability Exchange, Washington University in St. Louis, Spring 202

Sensate sovereignty : A dialogue on Dylan Robinson's hungry lIstening

Dylan Robinson's Hungry Listening: Resonant Theory for Indigenous Sound Studies emerges from encounters between Indigenous sound performance and Western art music. The book takes aim at the pernicious tendency for the latter to insist upon aesthetic assimilation as the end-goal of these encounters, which far too often means derogating the former’s ontologies and protocols of song. In this dialogue-review, members from the The Culture and Technology Discussion and Working Group (The CATDAWG) situate the book within sound studies and critiques of settler colonial listening, reflecting on the major conceptual contributions of the book such as sensate sovereignty, hungry listening, and critical listening positionality

Concert recording 2019-04-13

[Track 1]. Go / Mike Forbes -- [Track 2]. A tribute from the East / Jiro Censhu -- [Track 3]. Conversations. I. Allegretto [Track 4]. II. Lento [Track 5]. III. Jaunty / Barbara York -- [Track 6]. Two Faure duets. I. Puisqu\u27ici-bas toute ame [Track 7]. II. Tarentelle / Gabriel Faure arranged by Steven Mead -- [Track 8]. El Alacran / David Cutler -- [Track 9]. The yellow rose of Texas variations / Lewis J. Buckley

Investigating the Heart of a Community: Archaeological Excavations at the African Meeting House, Boston, Massachusetts

In collaboration with the Museum of African American History, an archaeological research team from the University of Massachusetts Boston carried out a data recovery excavation at the African Meeting House on Beacon Hill. The African Meeting House was a powerful social institution for 19thcentury Boston’s free black community. The site played an important role in the abolition movement, the creation of educational opportunity, and other community action for social and political equality. The Meeting House was originally built in 1806, and renovations in preparation for the 2006 bi-centennial celebration prompted an investigation of areas of the property to be impacted by the proposed construction. Archaeological fieldwork, conducted under Massachusetts Historical Commission Permit Number 2750, was spread over seven weeks in May through July 2005. The field team opened and explored about 19 m2 of the site in the backlot south of the Meeting House and alley to the west. These excavations recorded information about a series of significant features and deposits, and collected over 38,000 artifacts and a series of soil samples for a detailed archaeobiological research program. These excavations met the requirements of the data recovery program as outlined in 950 CMR 70.00 and in the Memorandum of Agreement for the project, and the proposed renovation work proceeded with a finding of no adverse effect (36 CFR 800.5(b)). The depositional history and the nature of the archaeological record allow us to separate the overall excavation into three sub-areas: 1) the west alley between the AMH and 2 Smith Court; 2) the historic Meeting House backlot; and 3) the south yard, which originally belonged to the 44 Joy Street property. In terms of significant features and deposits, the west alley was almost entirely a series of builders’ trenches reflecting the historic sequence of construction and remodeling of the Meeting House and adjacent buildings to the west. In the backlot, the units against the south wall of the Meeting House contained similar builders’ trenches. The backlot also contained a series of stone and brick drains and a trash-rich midden layer. The vast majority of artifacts in the Meeting House backlot date from about 1806–1840. The ceramics assemblage is particularly large, and reflects both community meals at the Meeting House and business of Domingo Williams, a caterer who rented a basement apartment. Finally, only one feature was studied in the south yard, a privy (outhouse) that was for the 44 Joy Street property. The bottommost layer of the privy was an artifact rich nightsoil layer, dating to about 1811–1838, and containing the trash of African American tenants living at 44 Joy Street. Together, the archaeological deposits in the backlot provide a variety of insights into living conditions, economic opportunity, foodways, health, and daily life for 19th-century Boston’s free black community. These results thus provide information to help further the research, interpretation, and public education goals of the Museum of African American History

Computer-aided whole-cell design:taking a holistic approach by integrating synthetic with systems biology

Computer-aided design for synthetic biology promises to accelerate the rational and robust engineering of biological systems; it requires both detailed and quantitative mathematical and experimental models of the processes to (re)design, and software and tools for genetic engineering and DNA assembly. Ultimately, the increased precision in the design phase will have a dramatic impact on the production of designer cells and organisms with bespoke functions and increased modularity. Computer-aided design strategies require quantitative representations of cells, able to capture multiscale processes and link genotypes to phenotypes. Here, we present a perspective on how whole-cell, multiscale models could transform design-build-test-learn cycles in synthetic biology. We show how these models could significantly aid in the design and learn phases while reducing experimental testing by presenting case studies spanning from genome minimization to cell-free systems, and we discuss several challenges for the realization of our vision. The possibility to describe and build in silico whole-cells offers an opportunity to develop increasingly automatized, precise and accessible computer-aided design tools and strategies throughout novel interdisciplinary collaborations

Fertility Desires and Intentions of HIV-Positive Women of Reproductive Age in Ontario, Canada: A Cross-Sectional Study

Improvements in life expectancy and quality of life for HIV-positive women coupled with reduced vertical transmission will likely lead numerous HIV-positive women to consider becoming pregnant. In order to clarify the demand, and aid with appropriate health services planning for this population, our study aims to assess the fertility desires and intentions of HIV-positive women of reproductive age living in Ontario, Canada.A cross-sectional study with recruitment stratified to match the geographic distribution of HIV-positive women of reproductive age (18-52) living in Ontario was carried out. Women were recruited from 38 sites between October 2007 and April 2009 and invited to complete a 189-item self-administered survey entitled "The HIV Pregnancy Planning Questionnaire" designed to assess fertility desires, intentions and actions. Logistic regression models were fit to calculate unadjusted and adjusted odds ratios of significant predictors of fertility intentions. The median age of the 490 participating HIV-positive women was 38 (IQR, 32-43) and 61%, 52%, 47% and 74% were born outside of Canada, living in Toronto, of African ethnicity and currently on antiretroviral therapy, respectively. Of total respondents, 69% (95% CI, 64%-73%) desired to give birth and 57% (95% CI, 53%-62%) intended to give birth in the future. In the multivariable model, the significant predictors of fertility intentions were: younger age (age<40) (p<0.0001), African ethnicity (p<0.0001), living in Toronto (p = 0.002), and a lower number of lifetime births (p = 0.02).The proportions of HIV-positive women of reproductive age living in Ontario desiring and intending pregnancy were higher than reported in earlier North American studies. Proportions were more similar to those reported from African populations. Healthcare providers and policy makers need to consider increasing services and support for pregnancy planning for HIV-positive women. This may be particularly significant in jurisdictions with high levels of African immigration

Abnormal Capillary Vasodynamics Contribute to Ictal Neurodegeneration in Epilepsy

Seizure-driven brain damage in epilepsy accumulates over time, especially in the hippocampus, which can lead to sclerosis, cognitive decline, and death. Excitotoxicity is the prevalent model to explain ictal neurodegeneration. Current labeling technologies cannot distinguish between excitotoxicity and hypoxia, however, because they share common molecular mechanisms. This leaves open the possibility that undetected ischemic hypoxia, due to ictal blood flow restriction, could contribute to neurodegeneration previously ascribed to excitotoxicity. We tested this possibility with Confocal Laser Endomicroscopy (CLE) and novel stereological analyses in several models of epileptic mice. We found a higher number and magnitude of NG2+ mural-cell mediated capillary constrictions in the hippocampus of epileptic mice than in that of normal mice, in addition to spatial coupling between capillary constrictions and oxidative stressed neurons and neurodegeneration. These results reveal a role for hypoxia driven by capillary blood flow restriction in ictal neurodegeneration