Hypersonic heat transfer and anisotropic visualization with a higher order discontinuous Galerkin finite element method

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.Includes bibliographical references (leaves 83-89).Higher order discretizations of the Navier-Stokes equations promise greater accuracy than conventional computational aerodynamics methods. In particular, the discontinuous Galerkin (DG) finite element method has O(hP+l) design accuracy and allows for subcell resolution of shocks. This work furthers the DG finite element method in two ways. First, it demonstrates the results of DG when used to predict heat transfer to a cylinder in a hypersonic flow. The strong shock is captured with a Laplacian artificial viscosity term. On average, the results are in agreement with an existing hypersonic benchmark. Second, this work improves the visualization of the higher order polynomial solutions generated by DG with an adaptive display algorithm. The new algorithm results in more efficient displays of higher order solutions, including the hypersonic flow solutions generated here.by Douglas J. Quattrochi.S.M

Calorie Restriction Enhances Longevity Without Reducing Lifetime Fecundity or Glucose Titers in Female Lubber Grasshoppers

Calorie restriction, under eating while avoiding malnutrition, enhances longevity in many organisms, in part by delaying fecundity or lowering blood glucose. Calorie restriction begun at middle-age can also enhance longevity. We tested four diets on longevity of female lubber grasshoppers: ad libitum (free access to food), calorie restriction (60% or 71% of ad libitum), and delayed calorie restriction (60% after day 50). Constant calorie restriction increased longevity in grasshoppers by at least 66%. These diets lowered body mass, but it did not reduce lifetime fecundity or chronically lower blood glucose levels. Calorie restriction reduced the levels of stored protein after egg laying. Delayed calorie restriction also increased longevity (also by 66%), but because the body mass gain of this group did keep pace with ad libitum grasshoppers when they were fed identically, this result needs retesting. These extensions of lifespan likely are due to slowed aging

How Cities Breathe: Ground-Referenced, Airborne Hyperspectral Imaging Precursor Measurements To Space-Based Monitoring

Methane's (CH4) large global warming potential (Shindell et al., 2012) and likely increasing future emissions due to global warming feedbacks emphasize its importance to anthropogenic greenhouse warming (IPCC, 2007). Furthermore, CH4 regulation has far greater near-term climate change mitigation potential versus carbon dioxide CO2, the other major anthropogenic Greenhouse Gas (GHG) (Shindell et al., 2009). Uncertainties in CH4 budgets arise from the poor state of knowledge of CH4 sources - in part from a lack of sufficiently accurate assessments of the temporal and spatial emissions and controlling factors of highly variable anthropogenic and natural CH4 surface fluxes (IPCC, 2007) and the lack of global-scale (satellite) data at sufficiently high spatial resolution to resolve sources. Many important methane (and other trace gases) sources arise from urban and mega-urban landscapes where anthropogenic activities are centered - most of humanity lives in urban areas. Studying these complex landscape tapestries is challenged by a wide and varied range of activities at small spatial scale, and difficulty in obtaining up-to-date landuse data in the developed world - a key desire of policy makers towards development of effective regulations. In the developing world, challenges are multiplied with additional political access challenges. As high spatial resolution satellite and airborne data has become available, activity mapping applications have blossomed - i.e., Google maps; however, tap a minute fraction of remote sensing capabilities due to limited (three band) spectral information. Next generation approaches that incorporate high spatial resolution hyperspectral and ultraspectral data will allow detangling of the highly heterogeneous usage megacity patterns by providing diagnostic identification of chemical composition from solids (refs) to gases (refs). To properly enable these next generation technologies for megacity include atmospheric radiative transfer modeling the complex and often aerosol laden, humid, urban microclimates, atmospheric transport and profile monitoring, spatial resolution, temporal cycles (diurnal and seasonal which involve interactions with the surrounding environment diurnal and seasonal cycles) and representative measurement approaches given traffic realities. Promising approaches incorporate contemporaneous airborne remote sensing and in situ measurements, nocturnal surface surveys, with ground station measuremen

A revised evolutionary history of the CYP1A subfamily : gene duplication, gene conversion, and positive selection

Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Journal of Molecular Evolution 62 (2006): 708-717, doi:10.1007/s00239-005-0134-z.Members of cytochrome P450 subfamily 1A (CYP1As) are involved in detoxification and bioactivation of common environmental pollutants. Understanding the functional evolution of these genes is essential to predicting and interpreting species differences in sensitivity to toxicity by such chemicals. The CYP1A gene subfamily comprises a single ancestral representative in most fish species and two paralogs in higher vertebrates, including birds and mammals. Phylogenetic analysis of complete coding sequences suggests that mammalian and bird paralog pairs (CYP1A1/2 and CYP1A4/5, respectively) are the result of independent gene duplication events. However, comparison of vertebrate genome sequences revealed that CYP1A genes lie within an extended region of conserved fine-scale synteny, suggesting that avian and mammalian CYP1A paralogs share a common genomic history. Algorithms designed to detect recombination between nucleotide sequences indicate that gene conversion has homogenized most of the length of the chicken CYP1A genes, as well as the 5’ end of mammalian CYP1As. Together, these data indicate that avian and mammalian CYP1A paralog pairs resulted from a single gene duplication event and that extensive gene conversion is responsible for the exceptionally high degree of sequence similarity between CYP1A4 and CYP1A5. Elevated non-synonymous/synonymous substitution ratios within a putatively unconverted stretch of ~250 bp suggests that positive selection may have reduced the effective rate of gene conversion in this region, which contains two substrate recognition sites. This work significantly alters our understanding of functional evolution in the CYP1A subfamily, suggesting that gene conversion and positive selection have been the dominant processes of sequence evolution.Funding for this work was provided by the NIH Superfund Basic Research Program at Boston University (5-P42-ES-07381) and by the Woods Hole Oceanographic Institution

EPA REGISTRATION AND LICENSING

Originally we had the old Federal Insecticide, Fungicide, Rodenticide Act (FIFRA) which involved Health, Education and Welfare, Interior, Food and Drug Administration but was administered by USDA. This has been changed by the passage of the Federal Environmental Pesticide Control Act (FEPCA). Now in certain cases you will find that EPA is working through the States under the FEPCA law to develop policy. You will find EPA and the amended FIFRA will play a very important role in your business for several years

Replication data for: Keeping a Low Profile: What Determines the Allocation of Aid by Non-Governmental Organizations?

We refine an earlier cross-national analysis by Koch, et al (2009) on the determinants of location and allocation decisions by international non-governmental organizations. Using a more explicit causal framework, multiple imputation and coarsened exact matching, we come to qualitatively similar but analytically more robust conclusions. Shared colonial heritage and shared religion increase the probability that a large international NGO locates in a country. The share of exports from an NGO’s home country that go to a recipient country does not affect the level of aid allocated by the NGO in the recipient country. More harmonious UNGA voting between an NGO’s home country and the recipient country decreases the level of aid allocated by the NGO in the recipient country. We also provide more credible and easily interpretable measures of effect size, and we discuss implications and directions for future research

Impact of the 2018-2020 Democratic Republic of Congo Ebola epidemic on health system utilization and health outcomes

# Background The 2018-2020 Ebola epidemic in the eastern Democratic Republic of Congo caused 3,481 infections and 2,299 deaths. The broader impact on health system utilization and health outcomes remains unclear. # Methods From January to March 2020, a cross-sectional survey was administered to 3,631 households in Ebola-affected and non-affected health zones in North Kivu province to collect data on health behaviors and health status. Using linear models, we tested for associations between residence in an Ebola zone and multiple outcomes. Additionally, administrative data from 56 health facilities in Ebola zones was used to test for statistically significant changes in medical procedures (e.g. Cesarean sections) and disease rates before and during the epidemic. # Results Comparing before the epidemic to during, we found no difference in monthly mean procedures per facility: measles vaccinations -58 (95% confidence interval, CI = -140, 24); Cesarean sections 1.4 (95% CI = -0.8, 3.6); laparotomy 0.2 (95% CI = -0.5, 0.9); open fractures 0.0 (95% CI = -0.1, 0.1); appendectomy 0.0 (95% CI = -0.3, 0.3); inguinal hernia 0.3 (95% CI = 0.0, 0.7). Households in Ebola zones were 16 percentage points (pp) (95% CI = 11, 21) more likely to report going to the hospital more often than normal because of free access, reported fewer measles vaccinations (-10pp 95% CI = -14, -5), and less willingness to vaccinate children (-6pp; 95% CI = -9, -3). However, administrative data showed no change in vaccination before and during Ebola in Ebola zones. Households in Ebola zones were 14pp less likely to report that a child had experienced measles (95% CI = -18, -11) and 8pp less likely to report that a child had experienced diarrhea (95% CI = -12, -4) since 1 Jan 2017. However, administrative data showed no change in either, comparing before-Ebola to during-Ebola in Ebola zones (difference in monthly mean procedures per facility: measles 5.6 (95% CI = -0.8, 12.0); diarrhea 41 (95% CI = -63, 145). # Conclusions The Ebola epidemic did not have large effects on health system utilization or health outcomes (other than Ebola virus disease). This suggests that the Congolese and international response successfully maintained health system capacity during the epidemic

Cash-like vouchers improve psychological well-being of vulnerable and displaced persons fleeing armed conflict

The psychological burden of conflict-induced displacement is severe. Currently, there are 80 million displaced persons around the world, and their number is expected to increase in upcoming decades. Yet, few studies have systematically assessed the effectiveness of programs that assist displaced persons, especially in settings of extreme vulnerability. We focus on eastern Democratic Republic of Congo, where myriad local armed conflicts have driven cycles of displacement for over 20 years. We conducted a within-village randomized field experiment with 976 households, across 25 villages, as part of the United Nations’ Rapid Response to Population Movements program. The program provided humanitarian relief to over a million people each year, including vouchers for essential nonfood items, such as pots, pans, cloth, and mattresses. The vouchers led to large improvements in psychological well-being: a 0.32 standard deviation unit (SDU) improvement at 6 weeks, and a 0.18 SDU improvement at 1 year. There is no evidence that the program undermined social cohesion within the village, which alleviates worries related to programs that target some community members but not others. Finally, there was no improvement in child health