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We propose a systematic method to construct crystal-based molecular structures often needed as input for computational chemistry studies. These structures include crystal 'slabs' with periodic boundary conditions (PBCs) and non-periodic solids such as Wulff structures. We also introduce a method to build crystal slabs with orthogonal PBC vectors. These methods are integrated into our code,Los Alamos Crystal Cut(LCC), which is open source and thus fully available to the community. Examples showing the use of these methods are given throughout the manuscript.
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PURPOSE/AIM OF THE STUDY: To report on the successful treatment of idiopathic intracranial hypertension (IIH) in a patient with venous sinus stenosis secondary to a persistent occipital-marginal sinus (POMS) utilizing venous sinus stenting. MATERIALS/METHODS: A 55-year-old female presented with headaches and blurry vision. Ophthalmologic examination demonstrated papilledema. Two lumbar punctures demonstrated opening pressures of 31 and 38 cmH2O and provided temporary symptom relief. Cerebral venography demonstrated hypoplastic bilateral transverse-sigmoid sinuses with dominant drainage through a persistent occipital-marginal sinus (POMS). Multiple enlarged arachnoid granulations resulted in stenosis in the marginal sinus with an 18 mmHg mean pressure gradient across the stenosis. RESULTS: The decision was made for venous sinus stenting of the POMS. Immediate post-stenting venography demonstrated resolution of the POMS stenosis with flow only into the POMS and a mean pressure gradient across the stenosis normalized to 2 mmHg. Six-month follow-up venography demonstrated continued stent patency and clinical symptoms remained resolved. She has remained symptom free at 18 months. CONCLUSION: This writing summarizes the utility of endovascular dural sinus stenting and the importance of recognizing the dominant dural sinus drainage route in the treatment of IIH.
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Cavidades Cranianas/cirurgia , Endoscopia/métodos , Pseudotumor Cerebral/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Stents , Resultado do TratamentoRESUMO
We have investigated the crystal structure and phase stability, elastic incompressibility, and electronic properties of PbS based on high-pressure neutron diffraction, in-situ electrical resistance measurements, and first-principles calculations. The refinements show that the orthorhombic phase is structurally isotypic with indium iodide (InI) adopting a Cmcm structure (B33). The cubic-to-orthorhombic transition occurs at â¼2.1(1) GPa with a 3.8% volume collapse and a positive Clausius-Clapeyron slope. Phase-transition induced elastic softening is also observed, which is presumably attributed to the enhanced metallic bonding in the B33 phase. On the basis of band structure simulations, the cubic and orthorhombic phases are typical of direct and indirect semiconductors with band gaps of 0.47(1) and 1.04(1) eV, respectively, which supports electrical resistivity measurements of an abrupt jump at the structural transition. On the basis of the resolved structure for B33, the phase transition paths for B1âB33âB2 involve translation of a trigonal prism in B1 and motion of the next-nearest neighbor Pb atom into {SPb7} coordination and subsequent lattice distortion in the B33 phase.
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Aim: The environment of the nursing program dean or director within a community college or state university can be politically, fiscally, and emotionally challenging. There are few studies that investigate that environment. The purpose of this study was to describe the major barriers and incentives facing these nursing deans or directors as they implemented their proposed interventions related to the Central Valley Nursing Diversity Project. Additionally, we sought to identify successful strategies used to keep the programs competitive for resources and status within their institutions and within their local communities. Methodology: The study is descriptive; the data collection method was structured interviews and data were analyzed using content analysis. Findings: Findings indicate that among the most difficult barriers faced by the directors and the faculty was the over subscribed status (more applicants than positions) of the programs. The deans or directors described three significant points that acted as barriers. These were 1) limited space in science laboratory pre-requisite courses, 2) limited classroom space in nursing courses, and 3) limited space in clinical (hospital) sites. The largest single external pressure reported was the reduction in funding and all deans or directors indicated they had difficulty hiring qualified or credentialed faculty. Conclusion: Colleges must manage more effectively student demand by modifying admissions criteria to be more selective and admit students with greater likelihood of graduating; encourage innovative partnerships between employers and schools of nursing; and increasing funding for nursing faculty salaries, classrooms, and laboratories.
Objetivo: El ambiente de un(a) decano(a) o director(a) o de un Programa de Enfermería en un colegio comunitario o una universidad estatal puede ser un reto político, físico y emocional. Hay pocos estudios que investiguen ese ambiente. El propósito de este estudio fue describir las principales barreras e incentivos que enfrentan las(os) decanas(os) o directoras(es) al implementar las intervenciones del Proyecto de Diversidad en Enfermería en el Valle Central. Adicionalmente, se identificaron estrategias exitosas para mantener competitivos a los programas en cuanto a recursos y estatus en las comunidades locales. Metodología: El estudio es descriptivo; la información se recolectó mediante entrevistas estructuradas y fue analizada mediante análisis de contenido. Hallazgos: La barrera más difícil fue la demanda exagerada de los programas. Las(os) decanas(os) o directoras(es) describieron tres barreras significativas: 1) espacio limitado en laboratorios de ciencias para los cursos pre-requisito, 2) espacio limitado en los salones de clase para los cursos de enfermería, 3) espacio limitado en los sitios de práctica clínica. La principal presión externa fue la reducción de financiación, lo que produce dificultades para conseguir docentes calificados. Conclusión: Las instituciones deben manejar más efectivamente la demanda estudiantil, modificar los criterios de admisión para hacerlos más selectivos y admitir estudiantes con mayor posibilidad de graduarse; promover alianzas innovadoras entre empleadores y escuelas de enfermería e incrementar la financiación para salarios de docentes, aulas de clase y laboratorios.
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Educação em Enfermagem , Planos e Programas de Saúde , Diretores Médicos , Estudantes de EnfermagemRESUMO
A poor public "image" of the nurse is believed to contribute to nurse shortages. We surveyed more than 3,000 college students in science and math courses in a seven-county region of California's Central Valley to assess their perceptions of a career as a nurse in relation to a career as a physical therapist, a high school teacher, or a physician. Students generally had favorable perceptions of nursing, with two-thirds agreeing that nursing has good income potential, job security, and interesting work. However, nursing lagged behind the other occupations in perceptions of independence at work and was more likely to be perceived as a "women's" occupation. Our findings suggest that these college students have generally gotten the message that nursing is a financially rewarding and desirable career, although they also perceive nursing to be less attractive on some important occupational characteristics such as job independence. Unless nursing training capacity expands substantially, the projected nurse shortage will occur. With continued aggressive marketing of nursing as a career, there is a risk of engendering a backlash from prospective students frustrated in their effort to find a slot in a nursing training program. Much work remains to be done to alter the image of nursing as a women's occupation and to transform the work environment of nurses to make a career in nursing more attractive.