56 research outputs found
Unfrustrated Qudit Chains and their Ground States
We investigate chains of 'd' dimensional quantum spins (qudits) on a line
with generic nearest neighbor interactions without translational invariance. We
find the conditions under which these systems are not frustrated, i.e. when the
ground states are also the common ground states of all the local terms in the
Hamiltonians. The states of a quantum spin chain are naturally represented in
the Matrix Product States (MPS) framework. Using imaginary time evolution in
the MPS ansatz, we numerically investigate the range of parameters in which we
expect the ground states to be highly entangled and find them hard to
approximate using our MPS method.Comment: 5 pages, 5 figures. Typos correcte
Robustly Safe Compilation
Secure compilers generate compiled code that withstands many target-level attacks such as alteration of control flow, data leaks or memory corruption. Many existing secure compilers are proven to be fully abstract, meaning that they reflect and preserve observational equivalence. Fully abstract compilation is strong and useful but, in certain cases, comes at the cost of requiring expensive runtime constructs in compiled code. These constructs may have no relevance for security, but are needed to accommodate differences between the source and target languages that fully abstract compilation necessarily needs
Reflections on Seminole Rock: The Past, Present, and Future of Deference to Agency Regulatory Interpretations
Seminole Rock (or Auer) deference has captured the attention of scholars, policymakers, and the judiciary. That is why Notice & Comment, the blog of the Yale Journal on Regulation and the American Bar Association’s Section of Administrative Law & Regulatory Practice, hosted an online symposium from September 12 to September 23, 2016 on the subject. This symposium contains over 20 contributions addressing different aspects of Seminole Rock deference.
Topics include: History of Seminole Rock Empirical Examinations of Seminole Rock Understanding Seminole Rock Within Agencies Understanding Seminole Rock as Applied to Tax, Environmental Law, and Criminal Sentencing Why Seminole Rock Matters Should the Supreme Court Overrule Seminole Rock? Would Overruling Seminole Rock Have Unintended Consequences? What Might the Supreme Court Do? What Might Congress Do? The Future of Seminole Roc
Estimating Grizzly and Black Bear Population Abundance and Trend in Banff National Park Using Noninvasive Genetic Sampling
We evaluated the potential of two noninvasive genetic sampling methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos) and black bear (U. americanus) populations in Banff National Park, Alberta, Canada. Using Huggins closed population mark-recapture models, we obtained the first precise abundance estimates for grizzly bears ( = 73.5, 95% CI = 64–94 in 2006; = 50.4, 95% CI = 49–59 in 2008) and black bears ( = 62.6, 95% CI = 51–89 in 2006; = 81.8, 95% CI = 72–102 in 2008) in the Bow Valley. Hair traps had high detection rates for female grizzlies, and male and female black bears, but extremely low detection rates for male grizzlies. Conversely, bear rubs had high detection rates for male and female grizzlies, but low rates for black bears. We estimated realized population growth rates, lambda, for grizzly bear males ( = 0.93, 95% CI = 0.74–1.17) and females ( = 0.90, 95% CI = 0.67–1.20) using Pradel open population models with three years of bear rub data. Lambda estimates are supported by abundance estimates from combined hair trap/bear rub closed population models and are consistent with a system that is likely driven by high levels of human-caused mortality. Our results suggest that bear rub surveys would provide an efficient and powerful means to inventory and monitor grizzly bear populations in the Central Canadian Rocky Mountains
New loci for body fat percentage reveal link between adiposity and cardiometabolic disease risk
To increase our understanding of the genetic basis of adiposity and its links to cardiometabolic disease risk, we conducted a genome-wide association meta-analysis of body fat percentage (BF%) in up to 100,716 individuals. Twelve loci reached genome-wide significance (P<5 × 10−8), of which eight were previously associated with increased overall adiposity (BMI, BF%) and four (in or near COBLL1/GRB14, IGF2BP1, PLA2G6, CRTC1) were novel associations with BF%. Seven loci showed a larger effect on BF% than on BMI, suggestive of a primary association with adiposity, while five loci showed larger effects on BMI than on BF%, suggesting association with both fat and lean mass. In particular, the loci more strongly associated with BF% showed distinct cross-phenotype association signatures with a range of cardiometabolic traits revealing new insights in the link between adiposity and disease risk
Large meta-analysis of genome-wide association studies identifies five loci for lean body mass
Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 x 10(-8)) or suggestively genome wide (p < 2.3 x 10(-6)). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/ near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/ near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass
New loci for body fat percentage reveal link between adiposity and cardiometabolic disease risk
To increase our understanding of the genetic basis of adiposity and its links to cardiometabolic disease risk, we conducted a genome-wide association meta-analysis of body fat percentage (BF%) in up to 100,716 individuals. Twelve loci reached genome-wide significance (P <5 x 10(-8)), of which eight were previously associated with increased overall adiposity (BMI, BF%) and four (in or near COBLL1/GRB14, IGF2BP1, PLA2G6, CRTC1) were novel associations with BF%. Seven loci showed a larger effect on BF% than on BMI, suggestive of a primary association with adiposity, while five loci showed larger effects on BMI than on BF%, suggesting association with both fat and lean mass. In particular, the loci more strongly associated with BF% showed distinct cross-phenotype association signatures with a range of cardiometabolic traits revealing new insights in the link between adiposity and disease risk.Peer reviewe
MS
thesisOrgan injury in blunt trauma requires rapid diagnosis to obtain the best outcome, and the optimal means of diagnosis continues to be refined. The focused abdominal sonography in trauma (FAST) examination was initially developed to help rapidly identify those blunt trauma patients who require emergent laparotomy. Since first validated in these patients, the clinical use of the FAST exam has expanded to include all trauma patients generally. When applied to hemodynamically stable blunt trauma patients, the FAST exam is less sensitive for detecting internal injury, and particularly for detecting the need for laparotomy. Combining FAST results with a measure of hemodynamic stability might better predict the need for emergent laparotomy as a therapeutic intervention and thus give a more meaningful predictive value to the positive test. In this study, determination was made as to whether a first measured shock index of > 1, when combined with a positive FAST examination, better predicts the need for therapeutic laparotomy in blunt trauma patients than FAST alone. If validated, such a rule might be used as a decision support element of a computerized clinical point-of-care documentation tool for the traumatically injured. We performed a retrospective, case-control study to evaluate the predictive value of shock index and FAST exam on blunt trauma patients. Data were obtained from an American College of Surgeons-verified Level One trauma center during the year 2003. Patients were included in the study if they were injured by blunt mechanism and if they required the highest level of trauma team activation by standardized institutional criteria. Patients were excluded if they had prior diagnostic peritoneal lavage (DPL) or transfusion, or were less than 14 years of age. The lowest of first emergency department and pre-hospital-recorded values for heart rate and systolic blood pressure were used to calculate the shock index. Four hundred ninety-one patients were included in the study, 27 of whom underwent emergent laparotomy (rate 5.50%). Two of these laparotomies were classified as nontherapeutic."" 344 patients had FAST results recorded for analysis. The sensitivity of a positive FAST exam plus shock index > 1 for therapeutic laparotomy was 44.0% (95% CI 26.3-62.8%), specificity 99.4% (95% CI 98.0-99,9%). Comparing the predictive values of the two tests yielded: +FAST, SI > 1 = 74%; +FAST, SI 1 = 15%, -FAST, SI< 1 = 1% (each at p < 0.01). Results of both predictive tests were obtained using computerized data."
MS
thesisOrgan injury in blunt trauma requires rapid diagnosis to obtain the best outcome, and the optimal means of diagnosis continues to be refined. The focused abdominal sonography in trauma (FAST) examination was initially developed to help rapidly identify those blunt trauma patients who require emergent laparotomy. Since first validated in these patients, the clinical use of the FAST exam has expanded to include all trauma patients generally. When applied to hemodynamically stable blunt trauma patients, the FAST exam is less sensitive for detecting internal injury, and particularly for detecting the need for laparotomy. Combining FAST results with a measure of hemodynamic stability might better predict the need for emergent laparotomy as a therapeutic intervention and thus give a more meaningful predictive value to the positive test. In this study, determination was made as to whether a first measured shock index of > 1, when combined with a positive FAST examination, better predicts the need for therapeutic laparotomy in blunt trauma patients than FAST alone. If validated, such a rule might be used as a decision support element of a computerized clinical point-of-care documentation tool for the traumatically injured. We performed a retrospective, case-control study to evaluate the predictive value of shock index and FAST exam on blunt trauma patients. Data were obtained from an American College of Surgeons-verified Level One trauma center during the year 2003. Patients were included in the study if they were injured by blunt mechanism and if they required the highest level of trauma team activation by standardized institutional criteria. Patients were excluded if they had prior diagnostic peritoneal lavage (DPL) or transfusion, or were less than 14 years of age. The lowest of first emergency department and pre-hospital-recorded values for heart rate and systolic blood pressure were used to calculate the shock index. Four hundred ninety-one patients were included in the study, 27 of whom underwent emergent laparotomy (rate 5.50%). Two of these laparotomies were classified as nontherapeutic."" 344 patients had FAST results recorded for analysis. The sensitivity of a positive FAST exam plus shock index > 1 for therapeutic laparotomy was 44.0% (95% CI 26.3-62.8%), specificity 99.4% (95% CI 98.0-99,9%). Comparing the predictive values of the two tests yielded: +FAST, SI > 1 = 74%; +FAST, SI 1 = 15%, -FAST, SI< 1 = 1% (each at p < 0.01). Results of both predictive tests were obtained using computerized data."
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