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Dissecting racial bias in an algorithm used to manage the health of populations.
Health systems rely on commercial prediction algorithms to identify and help patients with complex health needs. We show that a widely used algorithm, typical of this industry-wide approach and affecting millions of patients, exhibits significant racial bias: At a given risk score, Black patients are considerably sicker than White patients, as evidenced by signs of uncontrolled illnesses. Remedying this disparity would increase the percentage of Black patients receiving additional help from 17.7 to 46.5%. The bias arises because the algorithm predicts health care costs rather than illness, but unequal access to care means that we spend less money caring for Black patients than for White patients. Thus, despite health care cost appearing to be an effective proxy for health by some measures of predictive accuracy, large racial biases arise. We suggest that the choice of convenient, seemingly effective proxies for ground truth can be an important source of algorithmic bias in many contexts
Semileptonic decays from full lattice QCD
We present first lattice QCD results for semileptonic form factors for the
decays and over the full
range, using both improved non-relativistic QCD (NRQCD) and fully relativistic
(HISQ) formalisms. These can be viewed as prototype calculations for
pseudoscalar to pseudoscalar and pseudoscalar to vector decays involving a transition. In particular we can use information from the relativistic
computations to fix the NRQCD current normalisations, which can then be used in
improved computations of decays such as and .Comment: 3 pages, 3 figures. Poster presented at the 16th International
Conference on B-Physics at Frontier Machines, 2-6 May 2016, Marseille, Franc
The Decay with Highly Improved Staggered Quarks and NRQCD
We report on progress of a lattice QCD calculation of the and
semileptonic form factors. We use a relativistic staggered
action (HISQ) for light and charm quarks, and an improved non-relativistic
(NRQCD) action for bottom, on the second generation MILC ensembles.Comment: Presented at Lattice 2017, the 35th International Symposium on
Lattice Field Theory at Granada, Spain (18-24 June 2017
Haploinsufficiency of the Myc regulator Mtbp extends survival and delays tumor development in aging mice.
Alterations of specific genes can modulate aging. Myc, a transcription factor that regulates the expression of many genes involved in critical cellular functions was shown to have a role in controlling longevity. Decreased expression of Myc inhibited many of the deleterious effects of aging and increased lifespan in mice. Without altering Myc expression, reduced levels of Mtbp, a recently identified regulator of Myc, limit Myc transcriptional activity and proliferation, while increased levels promote Myc-mediated effects. To determine the contribution of Mtbp to the effects of Myc on aging, we studied a large cohort of Mtbp heterozygous mice and littermate matched wild-type controls. Mtbp haploinsufficiency significantly increased longevity and maximal survival in mice. Reduced levels of Mtbp did not alter locomotor activity, litter size, or body size, but Mtbp heterozygous mice did exhibit elevated markers of metabolism, particularly in the liver. Mtbp(+/-) mice also had a significant delay in spontaneous cancer development, which was most prominent in the hematopoietic system, and an altered tumor spectrum compared to Mtbp(+/+) mice. Therefore, the data suggest Mtbp is a regulator of longevity in mice that mimics some, but not all, of the properties of Myc in aging
Technology in Teacher Education : Using Multimedia to Enhance the Design and Make Processes.
This paper reports on the use of a multimedia journal to enhance a subject in technology education. The subject was delivered to preservice teachers studying to be primary school teachers. The multimedia journal was used to assist in the delivery of the subject and to record the progress made by students. It is argued that multimedia used in this manner complements and extends upon the teaching program and becomes an integral part of the learning proces
Tracking REDD+ Finance: 2009-2012 - Finance Flows in Seven REDD+ Countries
Reducing Emissions from Deforestation and Forest Degradation (REDD). This REDDX report tracks the 2009-2012 flow of REDD+ finance from a variety of donors to seven tropical forest countries for various types of REDD+ activities. It is based on the hard work and dedication of seven teams of national partners and other experts who surveyed donors, government agencies, implementing agencies, NGOs, and consulting firms involved in the management of REDD+ finance in key REDD+ recipient countries
Medial prefrontal cortex lesions in mice do not impair effort-based decision making.
The function of the medial prefrontal cortex has previously been determined in the rat to play an important role in effort-based decision making and this, along with functions of other areas, has been assumed largely, to hold true in all rodents. In this study, we attempted to replicate this result in mice and to develop a model for effort-based decision making that could be useful for the study of neurological conditions. Mice were trained on a cost-benefit T-maze paradigm, whereby they chose between a low reward with little effort needed to obtain it or a higher reward, which required increased effort. Following training, the medial prefrontal cortex was lesioned. After surgery, contrary to earlier published rat studies, the performance of the mice did not change. In previous studies, prefrontal cortex lesioned rats chose the low effort/low reward option, but lesioned mice continued to select the high reward/high effort option. However, the other results are in line with previous mouse studies in both the extent of pathology and anxiety-like behaviour. These results illustrate a difference in the functioning of the prefrontal cortex between rats and mice and offer a word of caution on the interpretation of data from studies that employ different species
Electron and Hydride Addition to Gold (I) Thiolate Oligomers: Implications for Gold–Thiolate Nanoparticle Growth Mechanisms
Electron and hydride addition to Au(I):SR oligomers is investigated using density functional theory. Cyclic and chain-like clusters are examined in this work. Dissociation to Au– ions and Aun(SR)n+1– chains is observed after 2–4 electrons are added to these systems. The free thiolate (SR–) is rarely produced in this work; dissociation of Au– is preferred over dissociation of SR–. Electron affinities calculated in gas phase, toluene, and water suggest that the electron addition process is unlikely, although it may be possible in polar solvents. In contrast, hydride addition to Au(I):SR oligomers yields free thiols and complexes containing Au–Au bonds, which are plausible intermediates for gold nanoparticle growth. The resulting compounds can react to form larger nanoparticles or undergo further reduction by hydride to yield additional Au–Au bonds
Oxidation of Gold Clusters by Thiols
The formation of gold–thiolate nanoparticles via oxidation of gold clusters by thiols is examined in this work. Using the BP86 density functional with a triple ζ basis set, the adsorption of methylthiol onto various gold clusters AunZ (n = 1–8, 12, 13, 20; Z = 0, −1, +1) and Au384+ is investigated. The rate-limiting step for the reaction of one thiol with the gold cluster is the dissociation of the thiol proton; the resulting hydrogen atom can move around the gold cluster relatively freely. The addition of a second thiol can lead to H2 formation and the generation of a gold–thiolate staple motif
Characterization of Navassa National Wildlife Refuge: A preliminary report for NF-06-05 (NOAA ship "Nancy Foster", April 18-30, 2006)
Navassa is a small, undeveloped island in the Windward Passage between Jamaica and Haiti. It was designated a National Wildlife Refuge under the jurisdiction of the U.S. Fish and Wildlife Service in 1999, but the remote location makes management and enforcement challenging, and the area is regularly fished by artisanal fishermen from Haiti. In April 2006, the NOAA Center for Coastal Fisheries and Habitat Research conducted a research cruise to Navassa. The cruise produced the first high-resolution multibeam bathymetry for the area, which will facilitate habitat mapping and assist in refuge management. A major emphasis of the cruise was to study the impact of Haitian fishing gear on benthic habitats and fish communities; however, in 10 days on station only one small boat was observed with five fishermen and seven traps. Fifteen monitoring stations were established to characterize fish and benthic communities along the deep (28-34 m) shelf, as these areas have been largely unstudied by previous cruises. The fish communities included numerous squirrelfishes, triggerfishes, and parrotfishes. Snappers and grouper were also present but no small individuals were observed. Similarly, conch surveys indicated the population was in low abundance and was heavily skewed towards adults. Analysis of the benthic photoquadrats is currently underway. Other cruise activities included installation of a temperature logger network, sample collection for stable isotope analyses to examine trophic structure, and drop camera surveys to ground-truth habitat maps and overhead imagery. (PDF contains 58 pages
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