3,950 research outputs found
Stable phase field approximations of anisotropic solidification
We introduce unconditionally stable finite element approximations for a phase
field model for solidification, which take highly anisotropic surface energy and kinetic
effects into account. We hence approximate Stefan problems with anisotropic
Gibbs{Thomson law with kinetic undercooling, and quasi-static variants thereof.
The phase field model is given by
#wt + ïżœ %(') 't = r: (b(')rw) ;
c
a
ïżœ %(')w = " ïżœ
ïżœ ïżœ(r') '
13 + 1: A Comparison of Global Climate Change Policy Architectures
We critically review the Kyoto Protocol and thirteen alternative policy architectures for addressing the threat of global climate change. We employ six criteria to evaluate the policy proposals: environmental outcome, dynamic efficiency, cost effectiveness, equity, flexibility in the presence of new information, and incentives for participation and compliance. The Kyoto Protocol does not fare well on a number of criteria, but none of the alternative proposals fare well along all six dimensions. We identify several major themes among the alternative proposals: Kyoto is âtoo little, too fastâ; developing countries should play a more substantial role and receive incentives to participate; implementation should focus on market-based approaches, especially those with price mechanisms; and participation and compliance incentives are inadequately addressed by most proposals. Our investigation reveals tensions among several of the evaluative criteria, such as between environmental outcome and efficiency, and between cost-effectiveness and incentives for participation and compliance.policy architecture, Kyoto Protocol, efficiency, cost effectiveness, equity,participation, compliance
Asthma and COPD medicines prescription-claims:A time-series analysis of Englandâs national prescriptions during the COVID-19 pandemic (Jan 2019 to Oct 2020)
Detection and Attribution of Long-Term Vegetation Changes in Northern Alaska
Climate change is impacting terrestrial ecosystems world-wide and the Arctic is particularly vulnerable as it is warming faster and with greater magnitude than other regions. Understanding the responses of arctic plants species to abiotic factors is crucial to predicting the impact climate change will have on the Arctic because plants play critical roles in carbon exchange, energy balance, and trophic interactions. Using data from long-term research sites in Barrow and Atqasuk, Alaska, the purpose of this thesis was to investigate how arctic plants respond to 17-19 years of experimental warming, establish the relative strengths of various abiotic factors in predicting the response of plant traits over time, and examine evidence that climate change will significantly affect plants as the region continues to warm. Plants typically responded to longterm experimental warming with increased inflorescence heights, increased leaf lengths, and accelerated reproductive phenologies, while reproductive efforts responded less consistently. Further analysis revealed that responses to experimental warming tended to dampen during warmer years. Though mostly non-significant, several abiotic factors showed trends over time consistent with regional warming patterns observed in the Barrow area including increasing air and soil temperatures, earlier snowmelts, delayed freeze-ups, drier soils, and increasing thaw depths. Several plant species showed significant trends toward increasing inflorescence heights and reproductive efforts over the same time period. Of the abiotic factors examined, air and soil temperatures yielded the greatest predictive capabilities as these factors were consistently correlated with the greatest number of traits across sites. Unlike other traits, the reproductive efforts of many species were best predicted using temperatures during the year prior to flower burst. When we compared experimental warming responses with trends in abiotic factors and traits over time we found strong evidence that climate change will likely cause significant shifts 5 in the growth and reproductive efforts of at least seven plant species at these sites. This study illustrates the value of long-term monitoring coupled with experimentation and lays the groundwork for future studies examining the ecosystem consequences of climate change on the Barrow region
Naloxone/Buprenorphine, Methadone, Naltrexone and Their Role in Medication Assisted Treatment
Abstract
Opioid use disorder (OUD) is an increasingly common diagnosis that has drastically increased in the last 5 years. Though multiple treatment modalities exist for treating OUD (naltrexone, buprenorphine, methadone), few studies have compared treatment outcomes in adults on long term therapy. This is an important topic to understand as providers as we will undoubtedly come into contact with patients either actively abusing opioid antagonists or in recovery from opioid abuse. Since the introduction of Oxycontin and subsequent over prescription of opioid analgesics, opioid overdoses have increased by over twelve-fold. Once providers began to realize a widespread pattern of abuse, patients were widely taken off their prescriptions and turned to illegal means of purchasing opioids. Treatment outcomes with greater efficacy are highly sought after due to the increased mortality associated with opioid relapse, largely due to the introduction of fentanyl into opioid products acquired in a non-medical setting. Along from pure fentanyl introduced into products sold in an illicit fashion as opioids, fentanyl analogues have become increasingly common to find in a laboratory evaluation of these products. This research aims to evaluate the efficacy of naltrexone and buprenorphine-naloxone in maintaining prolonged abstinence following opioid cessation
Kathy Lavezzo, Angels on the Edge of the World: Geography, Literature and English Community, 1000-1534. Cornell University Press, 2006
Thirteen Plus One: A Comparison of Global Climate Policy Architectures
We critically review the Kyoto Protocol and thirteen alternative policy architectures for addressing the threat of global climate change. We employ six criteria to evaluate the policy proposals: environmental outcome, dynamic efficiency, cost effectiveness, equity, flexibility in the presence of new information, and incentives for participation and compliance. The Kyoto Protocol does not fare well on a number of criteria, but none of the alternative proposals fare well along all six dimensions. We identify several major themes among the alternative proposals: Kyoto is âtoo little, too fastâ; developing countries should play a more substantial role and receive incentives to participate; implementation should focus on market-based approaches, especially those with price mechanisms; and participation and compliance incentives are inadequately addressed by most proposals. Our investigation reveals tensions among several of the evaluative criteria, such as between environmental outcome and efficiency, and between cost-effectiveness and incentives for participation and compliance.Policy architecture, Kyoto Protocol, Efficiency, Cost effectiveness, Equity, Participation, Compliance
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