3,528 research outputs found
Duped by Dope: The Sackler Family’s Attempt to Escape Opioid Liability and the Need to Close the Non-Debtor Release Loophole
The opioid epidemic continues to rage on in the United States, ravaging its rural populations. One of its main causes? OxyContin. Purdue Pharma (“Purdue”), the maker of OxyContin, aggressively marketed opioids to the American public while racking up a fortune of over $13 billion dollars for its owners,3 the Sackler family. As a result, roughly 3,000 lawsuits were filed against Purdue and members of the Sackler family. Generally, the lawsuits alleged that Purdue and members of the Sackler family knew OxyContin was highly addictive yet aggressively marketed high dosages of the drug and misrepresented the drug as nonaddictive and without side effects. Facing thousands of lawsuits with damages in the trillions, Purdue soon filed for Chapter 11 bankruptcy to halt litigation. Though Purdue and its executives have twice pleaded guilty to perpetuating the opioid epidemic in litigation with the federal government, the Sackler family has yet to be held liable for their involvement
Duped by Dope: The Sackler Family’s Attempt to Escape Opioid Liability and the Need to Close the Non-Debtor Release Loophole
The opioid epidemic continues to rage on in the United States, ravaging its rural populations. One of its main causes? OxyContin. Purdue Pharma (“Purdue”), the maker of OxyContin, aggressively marketed opioids to the American public while racking up a fortune of over $13 billion dollars for its owners,3 the Sackler family. As a result, roughly 3,000 lawsuits were filed against Purdue and members of the Sackler family. Generally, the lawsuits alleged that Purdue and members of the Sackler family knew OxyContin was highly addictive yet aggressively marketed high dosages of the drug and misrepresented the drug as nonaddictive and without side effects. Facing thousands of lawsuits with damages in the trillions, Purdue soon filed for Chapter 11 bankruptcy to halt litigation. Though Purdue and its executives have twice pleaded guilty to perpetuating the opioid epidemic in litigation with the federal government, the Sackler family has yet to be held liable for their involvement
Initial Chemical Events in the Energetic Material RDX under Shock Loading: Role of Defects
We use the recently developed reactive force field ReaxFF with molecular dynamics (MD) to study the role of voids on the initial chemical events in the high-energy material RDX under shock loading. We find that for strong shocks (particles velocity of 3 km/s) very small gaps (2 nm) lead to important over-heating (~ 1000 K). This over-heating facilitates chemical reactions and leads to a larger production of small molecules (such as NO2, NO, OH) than in perfect crystals shocked with the same strength. The chemical reactions occur after the void has collapsed and the ejected material re-compressed rather than when hot molecules are ejected out of the downstream surface
Series of experiments for empirical validation of solar gain modelling in building energy simulation codes - experimental setup, test cell characterization, specifications and uncertainty analysis
Empirical validation of building energy simulation codes is an important component in understanding the capacity and limitations of the software. Within the framework of Task 34/Annex 43 of the International Energy Agency (IEA), a series of experiments was performed in an outdoor test cell. The objective of these experiments was to provide a high-quality data set for code developers and modelers to validate their solar gain models for windows with and without shading devices. A description of the necessary specifications for modeling these experiments is provided in this paper, which includes information about the test site location, experimental setup, geometrical and thermophysical cell properties including estimated uncertainties. Computed overall thermal cell properties were confirmed by conducting a steady-state experiment without solar gains. A transient experiment, also without solar gains, and corresponding simulations from four different building energy simulation codes showed that the provided specifications result in accurate thermal cell modeling. A good foundation for the following experiments with solar gains was therefore accomplished
Complex hyperkähler structures defined by Donaldson–Thomas invariants
The notion of a Joyce structure was introduced in Bridgeland (Geometry from Donaldson–Thomas invariants, preprint arXiv:1912.06504) to describe the geometric structure on the space of stability conditions of a CY3 category naturally encoded by the Donaldson-Thomas invariants. In this paper we show that a Joyce structure on a complex manifold defines a complex hyperkähler structure on the total space of its tangent bundle, and give a characterisation of the resulting hyperkähler metrics in geometric terms
Empirical validation of models to compute solar irradiance on inclined surfaces for building energy simulation
Accurately computing solar irradiance on external facades is a prerequisite for reliably predicting thermal behavior and cooling loads of buildings. Validation of radiation models and algorithms implemented in building energy simulation codes is an essential endeavor for evaluating solar gain models. Seven solar radiation models implemented in four building energy simulation codes were investigated: (1) isotropic sky, (2) Klucher, (3) Hay-Davies, (4) Reindl, (5) Muneer, (6) 1987 Perez, and (7) 1990 Perez models. The building energy simulation codes included: EnergyPlus, DOE-2.1E, TRNSYS-TUD, and ESP-r. Solar radiation data from two 25 days periods in October and March/April, which included diverse atmospheric conditions and solar altitudes, measured on the EMPA campus in a suburban area in Duebendorf, Switzerland, were used for validation purposes. Two of the three measured components of solar irradiances - global horizontal, diffuse horizontal and direct-normal - were used as inputs for calculating global irradiance on a south-west façade. Numerous statistical parameters were employed to analyze hourly measured and predicted global vertical irradiances. Mean absolute differences for both periods were found to be: (1) 13.7% and 14.9% for the isotropic sky model, (2) 9.1% for the Hay-Davies model, (3) 9.4% for the Reindl model, (4) 7.6% for the Muneer model, (5) 13.2% for the Klucher model, (6) 9.0%, 7.7%, 6.6%, and 7.1% for the 1990 Perez models, and (7) 7.9% for the 1987 Perez model. Detailed sensitivity analyses using Monte Carlo and fitted effects for N-way factorial analyses were applied to assess how uncertainties in input parameters propagated through one of the building energy simulation codes and impacted the output parameter. The implications of deviations in computed solar irradiances on predicted thermal behavior and cooling load of buildings are discussed
Thermal Decomposition of Condensed-Phase Nitromethane from Molecular Dynamics from ReaxFF Reactive Dynamics
We studied the thermal decomposition and subsequent reaction of the energetic material nitromethane (CH_3NO_2) using molecular dynamics with ReaxFF, a first principles-based reactive force field. We characterize the chemistry of liquid and solid nitromethane at high temperatures (2000−3000 K) and density 1.97 g/cm^3 for times up to 200 ps. At T = 3000 K the first reaction in the decomposition of nitromethane is an intermolecular proton transfer leading to CH_3NOOH and CH_2NO_2. For lower temperatures (T = 2500 and 2000 K) the first reaction during decomposition is often an isomerization reaction involving the scission of the C−N bond the formation of a C−O bond to form methyl nitrate (CH_3ONO). Also at very early times we observe intramolecular proton transfer events. The main product of these reactions is H_2O which starts forming following those initiation steps. The appearance of H_2O marks the beginning of the exothermic chemistry. Recent quantum-mechanics-based molecular dynamics simulations on the chemical reactions and time scales for decomposition of a crystalline sample heated to T = 3000 K for a few picoseconds are in excellent agreement with our results, providing an important, direct validation of ReaxFF
High On/Off Ratio Graphene Nanoconstriction Field Effect Transistor
We report a method to pattern monolayer graphene nanoconstriction field
effect transistors (NCFETs) with critical dimensions below 10 nm. NCFET
fabrication is enabled by the use of feedback controlled electromigration (FCE)
to form a constriction in a gold etch mask that is first patterned using
conventional lithographic techniques. The use of FCE allows the etch mask to be
patterned on size scales below the limit of conventional nanolithography. We
observe the opening of a confinement-induced energy gap as the NCFET width is
reduced, as evidenced by a sharp increase in the NCFET on/off ratio. The on/off
ratios we obtain with this procedure can be larger than 1000 at room
temperature for the narrowest devices; this is the first report of such large
room temperature on/off ratios for patterned graphene FETs.Comment: 18 pages, 6 figures, to appear in Smal
Identifying Assessment Opportunities in Postgraduate Learning for Sustainability
Abstract This paper offers a rationale for how ESD related learning at postgraduate level can be assessed. It proposes a framework for evaluating whether assessments in Master’s level programmes align with the pedagogical approach of Education for Sustainable Development (ESD). If assessment is to contribute to the overall learning process, then the nature of the assessment should reflect the pedagogy, values and principles associated with ESD. Utilising an Appreciative Inquiry model, existing models of competences for sustainable development have been used to develop the framework. The framework is not aimed at the performance of the students; rather, it is applied to the course itself to identify if assessment opportunities are in keeping with an ESD approach. The framework is applied to three examples from Master’s programmes, with which the authors are affiliated in England and Jamaica. The findings identify key characteristics that should feature in assessing learning for sustainability. The framework enabled the authors to gauge the extent to which their assessment regimes are in line with the aims, purpose and content of their programmes. While the examples cited are from the field of education, the framework can be applied to any Master’s programmes containing elements of sustainable development
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