4,915 research outputs found
Importance of van der Waals interactions for ab initio studies of topological insulators
We investigate the lattice and electronic structures of the bulk and surface
of the prototypical layered topological insulators BiSe and
BiTe using ab initio density functional methods, and systematically
compare the results of different methods of including van der Waals (vdW)
interactions. We show that the methods utilizing semi-empirical energy
corrections yield accurate descriptions of these materials, with the most
precise results obtained by properly accounting for the long-range tail of the
vdW interactions. The bulk lattice constants, distances between quintuple
layers and the Dirac velocity of the topological surface states (TSS) are all
in excellent agreement with experiment. In BiTe, hexagonal warping of
the energy dispersion leads to complex spin textures of the TSS at moderate
energies, while in BiSe these states remain almost perfectly helical
away from the Dirac point, showing appreciable signs of hexagonal warping at
much higher energies, above the minimum of the bulk conduction band. Our
results establish a framework for unified and systematic self-consistent first
principles calculations of topological insulators in bulk, slab and interface
geometries, and provides the necessary first step towards ab initio modeling of
topological heterostructures.Comment: 26 pages, 7 figures. This is the Accepted Manuscript version of an
article accepted for publication in Journal of Physics: Condensed Matter. IOP
Publishing Ltd is not responsible for any errors or omissions in this version
of the manuscript or any version derived from it. The Version of Record is
available online at https://dx.doi.org/10.1088/1361-648X/abbdb
"Against the Public": Teacher Strikes and the Decline of Liberalism, 1968-1981
In the 1930s, the Democratic Party became the party of working people largely through its support of legislation encouraging the formation of labor unions. As the nation moved leftward, a liberal consensus emerged that placed support--in the name of both economic growth and greater social equality--for labor unions at it center. Support for this labor-liberalism declined considerably during the 1970s, paving the way for the neoliberal conservatism that has emerged in the last quarter century of American politics. This dissertation explains this shift by looking at the intersection between culture and the public sector labor movement in the postwar era. As unionized teachers became increasingly visible in American political culture in the 1960s, lengthy strikes by teachers in major metropolitan areas in the 1970s caused many Americans to question their assumptions about the role of the state and the importance of labor unions. Because of teachers' long-time cultural importance as providers of economic opportunity as well as inculcators of moral values, their labor stoppages (which were often violations of the law) caused many white working- and middle-class Americans to blame the excesses of the liberal state for moral decline and to re-think their views about what had made America so prosperous in the years following World War II. Further, the state's failure to solve the thorny problem of teachers shutting down the school system also caused many of these future "Reagan Democrats" to question the efficacy of the liberal state. With labor-liberalism discredited, free-market conservatives began, by the end of the decade, to argue persuasively for a shift to a more austere state, less government regulation of business, and for the privatization of social goods like education. This dissertation charts these larger developments by putting close examinations of teacher strikes in Newark, Philadelphia, Pittsburgh, Baltimore, and St. Louis in dialogue with the national trajectory of neoliberal conservatism
Far-ultraviolet Emission-line Morphologies of the Supernova Remnant G65.3+5.7
We present the first far-ultraviolet (FUV) emission-line morphologies of the
whole region of the supernova remnant (SNR) G65.3+5.7 using the FIMS/SPEAR
data. The morphologies of the C IV {\lambda}{\lambda}1548, 1551, He II
{\lambda}1640, and O III] {\lambda}{\lambda}1661, 1666 lines appear to be
closely related to the optical and/or soft X-ray images obtained in previous
studies. Dramatic differences between the C IV morphology and the optical [O
III] {\lambda}5007 image provide clues to a large resonant-scattering region
and a foreground dust cloud. The FUV morphologies also reveal the overall
distribution of various shocks in different evolutionary phases and an
evolutionary asymmetry between the east and the southwest sides in terms of
Galactic coordinates, possibly due to a Galactic density gradient in the global
scale. The relative X-ray luminosity of G65.3+5.7 to C IV luminosity is
considerably lower than those of the Cygnus Loop and the Vela SNRs. This
implies that G65.3+5.7 has almost evolved into the radiative stage in the
global sense and supports the previous proposal that G65.3+5.7 has lost its
bright X-ray shell and become a member of mixed-morphology SNRs as it has
evolved beyond the adiabatic stage.Comment: 6 pages, 3 figures, accepted for publication in The Ap
Estimating the Economic Impact of Disease on a Local Economy: The Case of Diabetes in the Lower Rio Grande Valley of Texas
The purpose of this study is to investigate the economic impact of wage reductions that people experience from contracting diabetes. Incorporating wage reduction information into an input-output model reveals that as diabetics' wages decrease by 0.36 and $0.38, respectively.Health Economics and Policy,
Problems in Human Rights and Transboundary Pollution
This case study was intended to be included in Anton & Shelton, Environmental Problems and Human Rights (Cambridge, 2011), but space limitations forced its omission from the printed text. Using the Application Instituting Proceedings in the International Court of Justice case involving Arial Herbicide Spraying (Ecuador v. Columbia) [2008] ICJ 4-28 General List No. 138 (March 31, 2008)(footnote omitted), this case study raises questions associated with human rights and international environmental law
Problems in Human Rights and Large Dams
This case study was intended to be included in Anton & Shelton, Environmental Problems and Human Rights (Cambridge, 2011), but space limitations forced its omission from the printed text. Among large infrastructure projects, damming rivers to provide hydroelectric power have been the source of considerable conflict between governments and the people who are affected by such projects, especially those forced to relocate. In many instances dams are built in pristine natural areas, destroying or degrading nature reserves, indigenous lands and/or archaeological sites. Increasing opposition to large dams has resulted in national and international litigation, as well as substantial changes in the practices of international financial institutions. This case study looks at the case of the Narmada dam in India, as it has evolved over time in response to public action, national litigation, and challenges to World Bank financing. In reading these materials, consider the following issues: (1) In developing countries, do the benefits of flood control and the provision of renewable energy outweigh the environmental and human rights impacts of large dams? (2) Can equal or greater benefits be achieved by alternative development projects that have fewer negative impacts on the environment and human rights? (3) By what procedures and substantive measures can the negative impacts be avoided or mitigated? (4) Even if there are considerable benefits to hydroelectric projects, should certain locations be off-limits to the construction of large dams? If so, what are the relevant criteria by which to decide? (5) How should the rights of local communities and indigenous populations be safeguarded
T-lymphocyte-rich thymoma and myasthenia gravis in a Siberian tiger (Panthera tigris altaica)
A 10-year-old captive male Siberian tiger (Panthera tigris altaica) presented with acute onset collapse, vomiting and dyspnoea, preceded by a 6-month period of progressive muscle wasting. Following humane destruction, post-mortem examination revealed a large multilobulated mass in the cranial mediastinum, which was diagnosed as a T-lymphocyte-rich thymoma with the aid of immunohistochemistry. Retrospective serology for acetylcholine receptor antibodies (titre 3.90 nmol/l) confirmed a diagnosis of thymoma-associated myasthenia gravis. Thymomas are reported rarely in wild carnivores, but when detected they appear to be similar in morphology to those seen in domestic carnivores and may also be accompanied by paraneoplastic syndromes. The clinical signs of myasthenia gravis in the tiger were consistent with those reported in cats and dogs and the condition is proposed as an important differential diagnosis for generalized weakness in captive Felidae
Trans Adults Amidst the COVID-19 Pandemic: Quality of Life, Pandemic Impact, and Vaccine Preferences
The ongoing COVID-19 pandemic is disproportionately impacting marginalized communities, such as Black, Indigenous, and people of color (BIPOC), disabled individuals, and transgender/nonbinary (i.e., trans) individuals. As trans individuals may be multiply marginalized, it is necessary to examine within group differences among trans individuals of different genders, races, socioeconomic statuses, and abilities. This study examines the following research questions: (1) What is the quality of life of trans adults during the COVID-19 pandemic? (2) How does the self-reported impact of the pandemic vary across groups within the trans community? (3) What preferences do trans adults have regarding receiving a COVID-19 vaccine? Survey data were collected in August/September of 2020. Among a sample of 449 trans adults, findings suggest that the profound impact of the pandemic was not consistent across all community members. Being a woman predicted a higher self-reported impact of the pandemic while being a masc(uline) white respondent tended to predict a lower impact of the pandemic. Higher income was associated with a higher quality of life and being a disabled white respondent predicted a lower quality of life. The majority (99%) of the sample reported wanting to receive a COVID-19 vaccine should one become available. Implications for practice include the importance of considering the holistic experiences of clients and community members, as opposed to having homogenized perspectives of even subsets of the trans community. Future research related to barriers faced when attempting to access a vaccine is needed to inform future public health responses to epidemics/pandemics impacting this community.ECU Open Access Publishing Support Fun
Validation of an ICD code for accurately identifying emergency department patients who suffer an out-of-hospital cardiac arrest.
AIM: International classification of disease (ICD-9) code 427.5 (cardiac arrest) is utilized to identify cohorts of patients who suffer out-of-hospital cardiac arrest (OHCA), though the use of ICD codes for this purpose has never been formally validated. We sought to validate the utility of ICD-9 code 427.5 by identifying patients admitted from the emergency department (ED) after OHCA.
METHODS: Adult visits to a single ED between January 2007 and July 2012 were retrospectively examined and a keyword search of the electronic medical record (EMR) was used to identify patients. Cardiac arrest was confirmed; and ICD-9 information and location of return of spontaneous circulation (ROSC) were collected. Separately, the EMR was searched for patients who received ICD-9 code 427.5. The kappa coefficient (κ) was calculated, as was the sensitivity and specificity of the code for identifying OHCA.
RESULTS: The keyword search identified 1717 patients, of which 385 suffered OHCA and 333 were assigned the code 427.5. The agreement between ICD-9 code and cardiac arrest was excellent (κ = 0.895). The ICD-9 code 427.5 was both specific (99.4%) and sensitive (86.5%). Of the 52 cardiac arrests that were not identified by ICD-9 code, 33% had ROSC before arrival to the ED. When searching independently on ICD-9 code, 347 patients with ICD-9 code 427.5 were found, of which 320 were true arrests. This yielded a positive predictive value of 92% for ICD-9 code 427.5 in predicting OHCA.
CONCLUSIONS: ICD-9 code 427.5 is sensitive and specific for identifying ED patients who suffer OHCA with a positive predictive value of 92%
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