2,296 research outputs found
Chiral effective field theory beyond the power-counting regime
Novel techniques are presented, which identify the chiral power-counting
regime (PCR), and realize the existence of an intrinsic energy scale embedded
in lattice QCD results that extend outside the PCR. The nucleon mass is
considered as a benchmark for illustrating this new approach. Using
finite-range regularization, an optimal regularization scale can be extracted
from lattice simulation results by analyzing the renormalization of the low
energy coefficients. The optimal scale allows a description of lattice
simulation results that extend beyond the PCR by quantifying and thus handling
any scheme-dependence. Preliminary results for the nucleon magnetic moment are
also examined, and a consistent optimal regularization scale is obtained. This
indicates the existence of an intrinsic scale corresponding to the finite size
of the source of the pion cloud.Comment: 6 pages, 4 figures, conferenc
Property Forms in Tension: Preference Inefficiency, Rent-Seeking, and the Problem of Notice in the Modern Condominium
There is tension in the universe of entity property forms-tension between the traditional conception of the residential leasehold interest and the expanding property form known as the common-interest community. Commoninterest communities, a mix of both fee simple and tenancy in common property, are distinguished by collective governance regimes that impose restrictions on property owners through the use of ever-evolving covenants. These restrictions are determined, amended, and enforced through majoritarian governance, such that these communities effectively form private governments. \u27 Condominiums, the subject of this Note, are among the fastest growing forms of these private governments
EikoNet: Solving the Eikonal Equation With Deep Neural Networks
The recent deep learning revolution has created enormous opportunities for accelerating compute capabilities in the context of physics-based simulations. In this article, we propose EikoNet, a deep learning approach to solving the Eikonal equation, which characterizes the first-arrival-time field in heterogeneous 3-D velocity structures. Our grid-free approach allows for rapid determination of the travel time between any two points within a continuous 3-D domain. These travel time solutions are allowed to violate the differential equation--which casts the problem as one of optimization--with the goal of finding network parameters that minimize the degree to which the equation is violated. In doing so, the method exploits the differentiability of neural networks to calculate the spatial gradients analytically, meaning that the network can be trained on its own without ever needing solutions from a finite-difference algorithm. EikoNet is rigorously tested on several velocity models and sampling methods to demonstrate robustness and versatility. Training and inference are highly parallelized, making the approach well-suited for GPUs. EikoNet has low memory overhead and further avoids the need for travel-time lookup tables. The developed approach has important applications to earthquake hypocenter inversion, ray multipathing, and tomographic modeling, as well as to other fields beyond seismology where ray tracing is essential
\u3ci\u3eMylanodon rosei\u3c/i\u3e, a New Metacheiromyid (Mammalia: Palaeanodonta) from the Late Tiffanian (Late Paleocene) of Northwestern Wyoming
Mylanodon rosei is a new genus and species of late Paleocene metacheiromyid palaeanodont from a new late Tiffanian locality, Y2K Quarry, in the Clarks Fork Basin, Wyoming. The type is an adult dentary with P4 and a molariform double-rooted M1. This provides the first evidence that molariform teeth were retained in early Metacheiromyidae. A second specimen is a juvenile dentary with a partial P3 and an unerupted P4. This is the first juvenile dentition known for a Paleocene metacheiromyid. The new specimens enable determination of dental homologies. Reduction of teeth in early metacheiromyids took place from back to front, opening the characteristic posterior diastema. Both Mylanodon and Propalaeanodon, a slightly older metacheiromyid, are intermediate morphologically and temporally between the older Tiffanian epoicotheriid Amelotabes and the younger Clarkforkian and Wasatchian metacheiromyid Palaeanodon. Propalaeanodon has a single-rooted M1, a derived characteristic not found in Mylanodon, suggesting that two lineages are involved and Propalaeanodon was not ancestral to Mylanodon
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Quality use of medicines within universal health coverage: challenges and opportunities
Background: Medicines are a major driver of quality, safety, equity, and cost of care in low and middle-income country health systems. Universal health coverage implementers must explicitly address appropriate use of medicines to realize the health benefits of medicines, avoid wasting scarce resources, and sustain the financial viability of universal health coverage schemes. Discussion Medicines are major contributors to the health and well-being of individuals and populations when used appropriately, and they waste resources and endanger health when used unnecessarily or incorrectly. Stakeholders need to balance inherently competing objectives in the pharmaceutical sector. Emerging and expanding UHC schemes provide potential levers to balance competing system objectives. To use these levers, sustainable universal coverage programs will require a) information systems that can track medicines utilization, expenditures, and quality of medicines use; b) routine monitoring of indicators of medicines availability, access, affordability, and use; c) policies and programs that facilitate appropriate medicines use by prescribers, dispensers, and patients; d) transparency in setting priorities for medicines coverage under resource constraints; and e) a system perspective to engage diverse actors. As they operationalize paths toward universal health coverage and include targeted medicines coverage policies and programs, systems can build on, and innovate, pharmaceutical policy frameworks and management tools from different countries’ settings. Summary Ensuring that medicines which achieve important health outcomes are available, accessible to all, used appropriately, and sustainably affordable is essential for realizing universal health coverage. Stakeholder cooperation and use of information and financing system levers provide opportunities to work toward this goal
Will They Stay or Will They Go? Analysis of the 2019 DOE Working Conditions Survey
This report is part of the MERC Teacher Retention study. This study was designed to identify patterns of teacher retention in the MERC region and to determine the school and system-level factors driving them. The study also provides an overview of state and regional policies and programs relevant to teacher retention, and includes evaluations of existing policies and initiatives to determine efficacy and cost benefit. Teacher shortages continue to be a problem in the United States. While a range of policy solutions have attempted to stem the loss of teachers, at the base of many of these efforts is the concept of teacher working conditions, that is the workplace elements related to a teacher’s ability to do their job. Working conditions have been associated with job satisfaction and retention. This report presents the findings from an analysis of the 2019 Virginia Department of Education Working Conditions Survey. The analysis considered the various factors that influence teacher working conditions and whether these working conditions predict a teacher’s intent to stay or leave their current school
Connexin36 knockout mice display increased sensitivity to pentylenetetrazol-induced seizure-like behaviors
Large-scale synchronous firing of neurons during seizures is modulated by electrotonic coupling between neurons via gap junctions. To explore roles for connexin36 (Cx36) gap junctions in seizures, we examined the seizure threshold of connexin36 knockout (Cx36KO) mice using a pentylenetetrazol (PTZ) model
STI testing and subsequent clinic attendance amongst test negative asymptomatic users of an internet STI testing service:one-year retrospective study
AIM: To explore the characteristics of online STI test users, and assess the frequency and factors associated with subsequent service use following a negative online STI test screen in individuals without symptoms.METHODS: One-year retrospective study of online and clinic STI testing within a large integrated sexual health service (Umbrella in Birmingham and Solihull, England) between January and December 2017. A multivariable analysis of sociodemographic and behavioural characteristics of patients was conducted. Sexual health clinic appointments occurring within 90 days of a negative STI test, in asymptomatic individuals who tested either online or in clinic were determined. Factors associated with online STI testing and subsequent clinic use were determined using generalized estimating equations and reported as odds ratios (OR) with corresponding 95% confidence intervals (CI).RESULTS: 31 847 online STI test requests and 40 059 clinic attendances incorporating STI testing were included. 79% (25020/31846) of online STI test users and 49% (19672/40059) of clinic STI test takers were asymptomatic. Online STI testing was less utilised (p<0.05) by men who have sex with men (MSM), non-Caucasians and those living in neighborhoods of greater deprivation. Subsequent clinic appointments within 90 days of an asymptomatic negative STI test occurred in 6.2% (484/7769) of the online testing group and 33% (4960/15238) for the clinic tested group. Re-attendance following online testing was associated with being MSM (aOR 2.55[1.58 to 4.09]-MSM vs Female) and a recent prior history of STI testing (aOR 5.65[4.30 to 7.43] 'clinic tested' vs 'No' recent testing history).CONCLUSIONS: Subsequent clinic attendance amongst online STI test service users with negative test results was infrequent, suggesting that their needs were being met without placing an additional burden on clinic based services. However, unequal use of online services by different patient groups suggests that optimised messaging and the development of online services in partnership with users are required to improve uptake.</p
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