Integrated Task And Data Parallel Programming: Language Design

his research investigates the combination of task and data parallel language constructs within a single programming language. There are an number of applications that exhibit properties which would be well served by such an integrated language. Examples include global climate models, aircraft design problems, and multidisciplinary design optimization problems. Our approach incorporates data parallel language constructs into an existing, object oriented, task parallel language. The language will support creation and manipulation of parallel classes and objects of both types (task parallel and data parallel). Ultimately, the language will allow data parallel and task parallel classes to be used either as building blocks or managers of parallel objects of either type, thus allowing the development of single and multi-paradigm parallel applications. 1995 Research Accomplishments In February I presented a paper at Frontiers '95 describing the design of the data parallel language subset. During the spring I wrote and defended my dissertation proposal. Since that time I have developed a runtime model for the language subset. I have begun implementing the model and hand-coding simple examples which demonstrate the language subset. I have identified an astrophysical fluid flow application which will validate the data parallel language subset. 1996 Research Agenda Milestones for the coming year include implementing a significant portion of the data parallel language subset over the Legion system. Using simple hand-coded methods, I plan to demonstrate (1) concurrent task and data parallel objects and (2) task parallel objects managing both task and data parallel objects. My next steps will focus on constructing a compiler and implementing the fluid flow application with the language. Concurrently, I will conduct a search for a real-world application exhibiting both task and data parallelism within the same program m. Additional 1995 Activities During the fall I collaborated with Andrew Grimshaw and Adam Ferrari to write a book chapter which will be included in Parallel Processing in C++ edited by Gregory Wilson. I also finished two courses, Compilers and Advanced Compilers, in 1995. These courses complete my class requirements at the University of Virginia. I have only my dissertation research and defense to complete

Activism, Advertising, and Far-Right Media: The Case of Sleeping Giants

This study examines the international activist movement known as Sleeping Giants, a social-media “campaign to make bigotry and sexism less profitable” (Sleeping Giants, n.d.). The campaign originated in the US with an anonymous Twitter account that enlisted followers in encouraging brands to pull their online advertising from Breitbart News. The campaign achieved dramatic success and rapidly spread to regions outside the US, with other anonymously run and loosely allied chapters emerging in 15 different nations (as well as a regional chapter for the EU). Many of these were initially created to take on Breitbart advertisers in their home countries, but in a number of cases they subsequently turned their attention to disrupting financial support for other far-right news media in—or impacting—their home countries. Based on interviews with leaders of eight Sleeping Giants chapters, as well as the related UK-based Stop Funding Hate campaign, this study examines the Sleeping Giants campaign with respect to its continuity with media activism of previous eras, while also seeking to understand its potential as one of the first high-profile activist campaigns to grapple with the impacts of programmatic advertising on the news ecosystem. In particular, we consider how the campaign’s interventions speak to the larger debate around the normative relationship between advertising and the performance of the news ecosystem

The seasonal origins and ages of water provisioning streams and trees in a tropical montane cloud forest

Determining the sources of water provisioning streams, soils, and vegetation can provide important insights into the water that sustains critical ecosystem functions now and how those functions may be expected to respond given projected changes in the global hydrologic cycle. We developed multi-year time series of water isotope ratios (δ18O and δ2H) based on twice-monthly collections of precipitation, lysimeter, and tree branch xylem waters from a seasonally dry tropical montane cloud forest in the southeastern Andes mountains of Peru. We then used this information to determine indices of the seasonal origins, the young water fractions (Fyw), and the new water fractions (Fnew) of soil, stream, and tree water. There was no evidence for intra-annual variation in the seasonal origins of stream water and lysimeter water from 1 m depth, both of which were predominantly comprised of wet-season precipitation even during the dry seasons. However, branch xylem waters demonstrated an intra-annual shift in seasonal origin: xylem waters were comprised of wet-season precipitation during the wet season and dry-season precipitation during the dry season. The young water fractions of lysimeter (&lt; 15 %) and stream (5 %) waters were lower than the young water fraction (37 %) in branch xylem waters. The new water fraction (an indicator of water ≤ 2 weeks old in this study) was estimated to be 12 % for branch xylem waters, while there was no significant evidence for new water in stream or lysimeter waters from 1 m depth. Our results indicate that the source of water for trees in this system varied seasonally, such that recent precipitation may be more immediately taken up by shallow tree roots. In comparison, the source of water for soils and streams did not vary seasonally, such that precipitation may mix and reside in soils and take longer to transit into the stream. Our insights into the seasonal origins and ages of water in soils, streams, and vegetation in this humid tropical montane cloud forest add to understanding of the mechanisms that govern the partitioning of water moving through different ecosystems.</p

Sixteen years of Collaborative Learning through Active Sense-making in Physics (CLASP) at UC Davis

This paper describes our large reformed introductory physics course at UC Davis, which bioscience students have been taking since 1996. The central feature of this course is a focus on sense-making by the students during the five hours per week discussion/labs in which the students take part in activities emphasizing peer-peer discussions, argumentation, and presentations of ideas. The course differs in many fundamental ways from traditionally taught introductory physics courses. After discussing the unique features of CLASP and its implementation at UC Davis, various student outcome measures are presented showing increased performance by students who took the CLASP course compared to students who took a traditionally taught introductory physics course. Measures we use include upper-division GPAs, MCAT scores, FCI gains, and MPEX-II scores.Comment: Also submitted to American Journal of Physic

Higher Rates of Head Contacts, Body Checking, and Suspected Injuries in Ringette Than Female Ice Hockey:Time to Ring in Opportunities for Prevention

Objective: Ringette is a popular team ice sport in Canada, primarily played by females. Bodychecking is prohibited at all levels of play. This study used video-analysis to evaluate physical contact (PC), head contact (HC), and suspected injury and concussion incidence rates (IR) in youth ringette. Study Design: Cross-sectional. Subjects: Youth ringette players from the 2021-2022 season playing in the U16 (ages 14-15) or U19 (ages 16-18) age groups (A or AA levels). Games were filmed from regular season, provincials, and nationals (AA only). Observation Technique: Game video-recordings were analyzed using Dartfish video-analysis software. Validated criteria were used to assess trunk PC intensity (levels 1-3=lower-intensity PC, levels 4-5=higher-intensity bodychecking), HC type (HC1=direct player-to-player, HC2=indirect), suspected injury (concussion, non-concussion), and penalty enforcement. Outcome Measures: Multivariable Poisson regression analyses (adjusted for cluster by teamgame, offset by game-minutes) were used to estimate PC, HC, and suspected injury and concussion IRs. Incidence rate ratios (IRR) were used to compare IR across age groups, levels of play, and game types. Proportions of bodychecks and HC1s penalized were reported. Results: Seventy-eight team-games were included (U16 n=40, U19 n=38; A n=30, AA n=48; regular season n=30, provincials n=32, nationals n=16). The overall bodychecking IR was 17.34/100 team-minutes (95% CI:14.80-20.33), HC 19.09/100 team-minutes (95% CI:16.7421.78), suspected injury 1.53/100 team-minutes (95% CI:1.13-2.09), and suspected concussion 0.74/100 team-minutes (95% CI:0.48-1.13). Only 29% (95% CI:24.97-32.59) of bodychecks and 7% (95% CI:4.76-9.70) of HC1s were penalized. No differences were found in bodychecking, HCs, or suspected injury and concussion IRs between age groups or levels of play. Bodychecking IRs were 64% (IRR=1.64; 95% CI:1.13-2.39) higher in provincials and 24% (IRR=1.24; 95% CI:1.02-1.50) higher in nationals than regular season games. A 31% (IRR=0.69; 95% CI:0.49-0.97) lower rate of HCs was reported in national games compared to provincial games. Bodychecking was the most common mechanism for concussion (70%) and nonconcussion injuries (67%), with concussions most often associated with HC2s (62.5%). Conclusions: Bodychecking and HC1 IRs were high among youth ringette players, despite rules prohibiting them. Future research should target prevention strategies aimed to reduce HC1s and bodychecking to reduce injury and concussion IRs in youth ringette

High rates of bodychecking, head conatcts, and suspected injuries found in youth ringette through video analysis.

Objective: Ringette is a popular team ice sport in Canada, primarily played by females. Bodychecking is prohibited at all levels of play. This study used video-analysis to evaluate physical contact (PC), head contact (HC), and suspected injury and concussion incidence rates (IR) in youth ringette. Study Design: Cross-sectional. Subjects: Youth ringette players from the 2021-2022 season playing in the U16 (ages 14-15) or U19 (ages 16-18) age groups (A or AA levels). Games were filmed from regular season, provincials, and nationals (AA only). Observation Technique: Game video-recordings were analyzed using Dartfish video-analysis software. Validated criteria were used to assess trunk PC intensity (levels 1-3=lower-intensity PC, levels 4-5=higher-intensity bodychecking), HC type (HC1=direct player-to-player, HC2=indirect), suspected injury (concussion, non-concussion), and penalty enforcement. Outcome Measures: Multivariable Poisson regression analyses (adjusted for cluster by teamgame, offset by game-minutes) were used to estimate PC, HC, and suspected injury and concussion IRs. Incidence rate ratios (IRR) were used to compare IR across age groups, levels of play, and game types. Proportions of bodychecks and HC1s penalized were reported. Results: Seventy-eight team-games were included (U16 n=40, U19 n=38; A n=30, AA n=48; regular season n=30, provincials n=32, nationals n=16). The overall bodychecking IR was 17.34/100 team-minutes (95% CI:14.80-20.33), HC 19.09/100 team-minutes (95% CI:16.7421.78), suspected injury 1.53/100 team-minutes (95% CI:1.13-2.09), and suspected concussion 0.74/100 team-minutes (95% CI:0.48-1.13). Only 29% (95% CI:24.97-32.59) of bodychecks and 7% (95% CI:4.76-9.70) of HC1s were penalized. No differences were found in bodychecking, HCs, or suspected injury and concussion IRs between age groups or levels of play. Bodychecking IRs were 64% (IRR=1.64; 95% CI:1.13-2.39) higher in provincials and 24% (IRR=1.24; 95% CI:1.02-1.50) higher in nationals than regular season games. A 31% (IRR=0.69; 95% CI:0.49-0.97) lower rate of HCs was reported in national games compared to provincial games. Bodychecking was the most common mechanism for concussion (70%) and nonconcussion injuries (67%), with concussions most often associated with HC2s (62.5%). Conclusions: Bodychecking and HC1 IRs were high among youth ringette players, despite rules prohibiting them. Future research should target prevention strategies aimed to reduce HC1s and bodychecking to reduce injury and concussion IRs in youth ringette

Phosphatidylinositide 3-kinase (PI3K) and PI3K-related kinase (PIKK) activity contributes to radioresistance in thyroid carcinomas.

Anaplastic (ATC) and certain follicular thyroid-carcinomas (FTCs) are radioresistant. The Phosphatidylinositide 3-kinase (PI3K) pathway is commonly hyperactivated in thyroid-carcinomas. PI3K can modify the PI3K-related kinases (PIKKs) in response to radiation: How PIKKs interact with PI3K and contribute to radioresistance in thyroid-carcinomas is unknown. Further uncertainties exist in how these interactions function under the radioresistant hypoxic microenvironment. Under normoxia/anoxia, ATC (8505c) and FTC (FTC-133) cells were irradiated, with PI3K-inhibition (via GDC-0941 and PTEN-reconstitution into PTEN-null FTC-133s) and effects on PIKK-activation, DNA-damage, clonogenic-survival and cell cycle, assessed. FTC-xenografts were treated with 5 × 2 Gy, ± 50 mg/kg GDC-0941 (twice-daily; orally) for 14 days and PIKK-activation and tumour-growth assessed. PIKK-expression was additionally assessed in 12 human papillary thyroid-carcinomas, 13 FTCs and 12 ATCs. GDC-0941 inhibited radiation-induced activation of Ataxia-telangiectasia mutated (ATM), ATM-and Rad3-related (ATR) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs). Inhibition of ATM and DNA-PKcs was PI3K-dependent, since activation was reduced in PTEN-reconstituted FTC-133s. Inhibition of PIKK-activation was greater under anoxia: Consequently, whilst DNA-damage was increased and prolonged under both normoxia and anoxia, PI3K-inhibition only reduced clonogenic-survival under anoxia. GDC-0941 abrogated radiation-induced cell cycle arrest, an effect most likely linked to the marked inhibition of ATR-activation. Importantly, GDC-0941 inhibited radiation-induced PIKK-activation in FTC-xenografts leading to a significant increase in time taken for tumours to triple in size: 26.5 ± 5 days (radiation-alone) versus 31.5 ± 5 days (dual-treatment). PIKKs were highly expressed across human thyroid-carcinoma classifications, with ATM scoring consistently lower. Interestingly, some loss of ATM and DNA-PKcs was observed. These data provide new insight into the mechanisms of hypoxia-associated radioresistance in thyroid-carcinoma

Development and characterization of a Yucatan miniature biomedical pig permanent middle cerebral artery occlusion stroke model

BACKGROUND: Efforts to develop stroke treatments have met with limited success despite an intense need to produce novel treatments. The failed translation of many of these therapies in clinical trials has lead to a close examination of the therapeutic development process. One of the major factors believed to be limiting effective screening of these treatments is the absence of an animal model more predictive of human responses to treatments. The pig may potentially fill this gap with a gyrencephalic brain that is larger in size with a more similar gray-white matter composition to humans than traditional stroke animal models. In this study we develop and characterize a novel pig middle cerebral artery occlusion (MCAO) ischemic stroke model. METHODS: Eleven male pigs underwent MCAO surgery with the first 4 landrace pigs utilized to optimize stroke procedure and 7 additional Yucatan stroked pigs studied over a 90 day period. MRI analysis was done at 24 hrs and 90 days and included T2w, T2w FLAIR, T1w FLAIR and DWI sequences and associated ADC maps. Pigs were sacrificed at 90 days and underwent gross and microscopic histological evaluation. Significance in quantitative changes was determined by two-way analysis of variance and post-hoc Tukey’s Pair-Wise comparisons. RESULTS: MRI analysis of animals that underwent MCAO surgery at 24 hrs had hyperintense regions in T2w and DWI images with corresponding ADC maps having hypointense regions indicating cytotoxic edema consistent with an ischemic stroke. At 90 days, region of interest analysis of T1 FLAIR and ADC maps had an average lesion size of 59.17 cc, a loss of 8% brain matter. Histological examination of pig brains showed atrophy and loss of tissue, consistent with MRI, as well as glial scar formation and macrophage infiltration. CONCLUSIONS: The MCAO procedure led to significant and consistent strokes with high survivability. These results suggest that the pig model is potentially a robust system for the study of stroke pathophysiology and potential diagnostics and therapeutics

Role of the highly conserved G68 residue in the yeast phosphorelay protein Ypd1: implications for interactions between histidine phosphotransfer (HPt) and response regulator proteins

Abstract Background Many bacteria and certain eukaryotes utilize multi-step His-to-Asp phosphorelays for adaptive responses to their extracellular environments. Histidine phosphotransfer (HPt) proteins function as key components of these pathways. HPt proteins are genetically diverse, but share a common tertiary fold with conserved residues near the active site. A surface-exposed glycine at the H + 4 position relative to the phosphorylatable histidine is found in a significant number of annotated HPt protein sequences. Previous reports demonstrated that substitutions at this position result in diminished phosphotransfer activity between HPt proteins and their cognate signaling partners. Results We report the analysis of partner binding interactions and phosphotransfer activity of the prototypical HPt protein Ypd1 from Saccharomyces cerevisiae using a set of H + 4 (G68) substituted proteins. Substitutions at this position with large, hydrophobic, or charged amino acids nearly abolished phospho-acceptance from the receiver domain of its upstream signaling partner, Sln1 (Sln1-R1). An in vitro binding assay indicated that G68 substitutions caused only modest decreases in affinity between Ypd1 and Sln1-R1, and these differences did not appear to be large enough to account for the observed decrease in phosphotransfer activity. The crystal structure of one of these H + 4 mutants, Ypd1-G68Q, which exhibited a diminished ability to participate in phosphotransfer, shows a similar overall structure to that of wild-type. Molecular modelling suggests that the highly conserved active site residues within the receiver domain of Sln1 must undergo rearrangement to accommodate larger H + 4 substitutions in Ypd1. Conclusions Phosphotransfer reactions require precise arrangement of active site elements to align the donor-acceptor atoms and stabilize the transition state during the reaction. Any changes likely result in an inability to form a viable transition state during phosphotransfer. Our data suggest that the high degree of evolutionary conservation of residues with small side chains at the H + 4 position in HPt proteins is required for optimal activity and that the presence of larger residues at the H + 4 position would cause alterations in the positioning of active site residues in the partner response regulator