91 research outputs found
Excursions at the North End of the Taconic Allochthon and the Middlebury Synclinorium, West-Central Vermont, with Emphasis on the Stucture of the Sundbury Nappe and Associated Parautochthonous Elements
Guidebook for field trips in Vermont: 64th annual meeting October 13, 14, 15, 1972 Burlington, Vermont: Trip B-
Egalitarian justice and expected value
According to all-luck egalitarianism, the differential distributive effects of both brute luck, which defines the outcome of risks which are not deliberately taken, and option luck, which defines the outcome of deliberate gambles, are unjust. Exactly how to correct the effects of option luck is, however, a complex issue. This article argues that (a) option luck should be neutralized not just by correcting luck among gamblers, but among the community as a whole, because it would be unfair for gamblers as a group to be disadvantaged relative to non-gamblers by bad option luck; (b) individuals should receive the warranted expected results of their gambles, except insofar as individuals blamelessly lacked the ability to ascertain which expectations were warranted; and (c) where societal resources are insufficient to deliver expected results to gamblers, gamblers should receive a lesser distributive share which is in proportion to the expected results. Where all-luck egalitarianism is understood in this way, it allows risk-takers to impose externalities on non-risk-takers, which seems counterintuitive. This may, however, be an advantage as it provides a luck egalitarian rationale for assisting ‘negligent victims’
A half-century of geologic and geothermic investigations in Iceland: The legacy of Kristjn Smundsson
One of the World's premier field geologists, Kristján Sæmundsson led immense geological mapping programs
and authored or co-authored nearly all geological maps of Iceland during the past half century, including the
first modern bedrock and tectonic maps of the whole country. These monumental achievements collectively
yield the most inclusive view of an extensional plate boundary anywhere on Earth. When Kristján began his
work in 1961, the relation of Iceland to sea-floor spreading was not clear, and plate tectonics had not yet been
invented. Kristján resolved key obstacles by demonstrating that the active rifting zones in Iceland had shifted
over time and were linked by complex transforms to the mid-ocean spreading ridge, thus making the concept
of sea-floor spreading in Iceland acceptable to those previously skeptical. Further, his insights and vast geological
and tectonic knowledge on both high- and low-temperature geothermal areas in Iceland yielded a major increase
in knowledge of geothermal systems, and probably no one has contributed more than he to Icelandic energy development. Kristján's legacy is comprised by his numerous superb maps on a variety of scales, the high quality
papers he produced, the impactful ideas generated that were internationally diffused, and the generations of colleagues and younger people he inspired, mentored, or otherwise positively influenced with his knowledge and
generous attitud
Abyssal hydrothermal springs-Cryptic incubators for brooding octopus
Does warmth from hydrothermal springs play a vital role in the biology and ecology of abyssal animals? Deep off central California, thousands of octopus (Muusoctopus robustus) migrate through cold dark waters to hydrothermal springs near an extinct volcano to mate, nest, and die, forming the largest known aggregation of octopus on Earth. Warmth from the springs plays a key role by raising metabolic rates, speeding embryonic development, and presumably increasing reproductive success; we show that brood times for females are ∼1.8 years, far faster than expected for abyssal octopods. Using a high-resolution subsea mapping system, we created landscapescale maps and image mosaics that reveal 6000 octopus in a 2.5-ha area. Because octopuses die after reproducing, hydrothermal springs indirectly provide a food supplement to the local energy budget. Although localized deep-sea heat sources may be essential to octopuses and otherwarm-tolerant species, most of these unique and often cryptic habitats remain undiscovered and unexplored
Pleiotropy Analysis of Quantitative Traits at Gene Level by Multivariate Functional Linear Models
In genetics, pleiotropy describes the genetic effect of a single gene on multiple phenotypic traits. A common approach is to analyze the phenotypic traits separately using univariate analyses and combine the test results through multiple comparisons. This approach may lead to low power. Multivariate functional linear models are developed to connect genetic variant data to multiple quantitative traits adjusting for covariates for a unified analysis. Three types of approximate F‐distribution tests based on Pillai–Bartlett trace, Hotelling–Lawley trace, and Wilks's Lambda are introduced to test for association between multiple quantitative traits and multiple genetic variants in one genetic region. The approximate F‐distribution tests provide much more significant results than those of F‐tests of univariate analysis and optimal sequence kernel association test (SKAT‐O). Extensive simulations were performed to evaluate the false positive rates and power performance of the proposed models and tests. We show that the approximate F‐distribution tests control the type I error rates very well. Overall, simultaneous analysis of multiple traits can increase power performance compared to an individual test of each trait. The proposed methods were applied to analyze (1) four lipid traits in eight European cohorts, and (2) three biochemical traits in the Trinity Students Study. The approximate F‐distribution tests provide much more significant results than those of F‐tests of univariate analysis and SKAT‐O for the three biochemical traits. The approximate F‐distribution tests of the proposed functional linear models are more sensitive than those of the traditional multivariate linear models that in turn are more sensitive than SKAT‐O in the univariate case. The analysis of the four lipid traits and the three biochemical traits detects more association than SKAT‐O in the univariate case.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111259/1/gepi21895.pd
Informed Conditioning on Clinical Covariates Increases Power in Case-Control Association Studies
Genetic case-control association studies often include data on clinical covariates, such as body mass index (BMI), smoking status, or age, that may modify the underlying genetic risk of case or control samples. For example, in type 2 diabetes, odds ratios for established variants estimated from low–BMI cases are larger than those estimated from high–BMI cases. An unanswered question is how to use this information to maximize statistical power in case-control studies that ascertain individuals on the basis of phenotype (case-control ascertainment) or phenotype and clinical covariates (case-control-covariate ascertainment). While current approaches improve power in studies with random ascertainment, they often lose power under case-control ascertainment and fail to capture available power increases under case-control-covariate ascertainment. We show that an informed conditioning approach, based on the liability threshold model with parameters informed by external epidemiological information, fully accounts for disease prevalence and non-random ascertainment of phenotype as well as covariates and provides a substantial increase in power while maintaining a properly controlled false-positive rate. Our method outperforms standard case-control association tests with or without covariates, tests of gene x covariate interaction, and previously proposed tests for dealing with covariates in ascertained data, with especially large improvements in the case of case-control-covariate ascertainment. We investigate empirical case-control studies of type 2 diabetes, prostate cancer, lung cancer, breast cancer, rheumatoid arthritis, age-related macular degeneration, and end-stage kidney disease over a total of 89,726 samples. In these datasets, informed conditioning outperforms logistic regression for 115 of the 157 known associated variants investigated (P-value = 1×10−9). The improvement varied across diseases with a 16% median increase in χ2 test statistics and a commensurate increase in power. This suggests that applying our method to existing and future association studies of these diseases may identify novel disease loci
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