2,991 research outputs found
Revising SA-CCR
From SA-CCR to RSA-CCR: making SA-CCR self-consistent and appropriately
risk-sensitive by cashflow decomposition in a 3-Factor Gaussian Market ModelComment: 20 pages, 13 table
Nursing students' intention to do Clinical Practice during Coronavirus Pandemic
Introduction: Coronavirus infections are known as a respiratory virus that cause disease ranging from a normal cold to a severe respiratory syndrome. On 30th January 2019 the world health organization announced the novel coronavirus (covid-19) as a public health emergency of international concern. Nursing education has significantly affected by this pandemic, Nursing students were forced to stop clinical practice for approximately one year and attend only online classes. During the first year of pandemic nursing students’ fail to do their clinical practice which is considered mandatory in students’ learning experience, the interaction between nursing students and other healthcare workers as well as patients is crucial. However there is a limited number of research evidences regarding the assessment of the nursing students' intention do clinical practice under the existence of covid-19 pandemic.
Objective: To examine how nursing students’ intention to do clinical practice during covid-19 is influenced. Methods: For the scooping review a literature search of electronic databases and web searching were conducted for published and unpublished articles. Four databases will be utilized: CINAHL, MEDLINE, PubMed and Scopus, Web of Science and Cochrane Library. For the cross‑sectional study students under course 33 (3rd year) and course 34 (4th year) at the school of Health Santarém were selected .Data was collected using online structured self-administered questionnaire (Survey Monkey platform used with license granted by the Quality Of Life Research Center, in which the supervisor José Amendoeira is an integrated member) The questionnaire is made up of four sections namely, socio-demographic variables, knowledge of covid‑19, students ‘perception, intention and readiness to do clinical practice.
Results: A total of 84 nursing students from the School of Health Santarém Portugal were included. The majority of responders were female (n=71, 84.5%) with mean age of 22.89 years old (SD=5.0), The duration of exposition to clinical practice was different among participants, 32 (38.1%) students were exposed to clinical practice for a period varying between 5 to 8 weeks, and the remaining 25 students (29.8%) were exposed to clinical practice for a period longer than three months. Furthermore, nursing students at the school of health Santarém showed good knowledge toward coronavirus disease; participants at the aforementioned school answered the majority of questions related coronavirus correctly. Responses related to perception showed that the majority of students 44 (52.4%) are having fear toward coronavirus. However, 62 (73.8%) of the respondents are satisfied with clinical practice during coronavirus time. Concerning the readiness and intention to practice 41 (48.8%) of students answered that they are ready to practice in clinical area and 31 (36.9%) of students are ready to practice where coronavirus patients exist.
Conclusion: Although the existence of Coronavirus Pandemic the nursing students’ intention to do clinical practice remains positive. However the variables that influence this intention are changing from one country to another
Deformation And Phase Transformation Processes In Polycrystalline Niti And Nitihf High Temperature Shape Memory Alloys
The unique ability of shape memory alloys (SMAs) to remember and recover their original shape after large deformation offers vast potential for their integration in advanced engineering applications. SMAs can generate recoverable shape changes of several percent strain even when opposed by large stresses owing to reversible deformation mechanisms such as twinning and stress-induced martensite. For the most part, these alloys have been largely used in the biomedical industry but with limited application in other fields. This limitation arises from the complexities of prevailing microstructural mechanisms that lead to dimensional instabilities during repeated thermomechanical cycling. Most of these mechanisms are still not fully understood, and for the most part unexplored. The objective of this work was to investigate these deformation and transformation mechanisms that operate within the low temperature martensite and high temperature austenite phases, and changes between these two states during thermomechanical cycling. This was accomplished by combined experimental and modeling efforts aided by an in situ neutron diffraction technique at stress and temperature. The primary focus was to investigate the thermomechanical response of a polycrystalline Ni49.9Ti50.1 (in at.%) shape memory alloy under uniaxial deformation conditions. Starting with the deformation of the cubic austenitic phase, the microstructural mechanisms responsible for the macroscopic inelastic strains during isothermal loading were investigated over a broad range of conditions. Stress-induced martensite, retained martensite, deformation twinning and slip processes were observed which helped in constructing a deformation map that contained the iv limits over which each of the identified mechanisms was dominant. Deformation of the monoclinic martensitic phase was also investigated where the microstructural changes (texture, lattice strains, and phase fractions) during room-temperature deformation and subsequent thermal cycling were captured and compared to the bulk macroscopic response of the alloy. This isothermal deformation was found to be a quick and efficient method for creating a strong and stable two-way shape memory effect. The evolution of inelastic strains with thermomechanical cycling of the same NiTi alloy, as it relates to the alloy stability, was also studied. The role of pre-loading the material in the austenite phase versus the martensite phase as a function of the active deformation modes (deformation processes as revealed in this work) were investigated from a macroscopic and microstructural perspective. The unique contribution from this work was the optimization of the transformation properties (e.g., actuation strain) as a function of deformation levels and pre-loading temperatures. Finally, the process used to set actuators, referred to as shape setting, was investigated while examining the bulk polycrystalline NiTi and the microstructure simultaneously through in situ neutron diffraction at stress and temperature. Knowledge gained from the binary NiTi study was extended to the investigation of a ternary Ni-rich Ni50.3Ti29.7Hf20 (in at.%) for use in high-temperature, high-force actuator applications. This alloy exhibited excellent dimensional stability and high work output that were attributed to a coherent, nanometer size precipitate phase that resulted from an aging treatment. Finally, work was initiated as part of this dissertation to develop sample environment equipment with multiaxial capabilities at elevated temperatures for the in situ neutron diffraction measurements of shape memory alloys on the VULCAN Diffractometer at Oak Ridge National Laboratory. The developed capability will immediately aid in making rapid multiaxial v measurements on shape memory alloys wherein the texture, strain and phase fraction evolution are followed with changes in temperature and stress. This work was supported by funding from the NASA Fundamental Aeronautics Program, Supersonics Project including (Grant No. NNX08AB51A). This work has also benefited from the use of the Lujan Neutron Scattering Center at LANSCE, which is funded by the Office of Basic Energy Sciences DOE. LANL is operated by Los Alamos National Security LLC under DOE Contract No. DE-AC52-06NA25396
Managing migration flows at the European level: a dilemma between externalizing European borders and creating legal pathways.
Effects of genotype and sowing date on phytostanol-phytosterol content and agronomic traits in wheat under organic agriculture
Cereals are an important source of sterols and stanols in the human diet. The present study underlines the effect of genotype and weather conditions in bread wheat, on total sterol and stanol content (TSS), agronomic traits, proteins and ash content under organic conditions. Variations in TSS as well as other characters between two sowing dates were observed. A broad genotypic variability was also reported since extreme genotypes differed by more than 30 mg 100. g-1 DW for TSS, with total stanol content varying twofold. Moreover, two groups of genotypes that differed in agronomic production, ash and protein content were depicted, based on their response to an increase in temperature. This result suggests that the genotypic factor prevails over the sowing date factor for determining sterol and stanol traits in wheat cultivated under organic conditions. Nevertheless, a strong interaction exists between the two factors, which can be used to drive bioaccumulation of these molecules
Insights on finite size effects in Ab-initio study of CO adsorption and dissociation on Fe 110 surface
Adsorption and dissociation of hydrocarbons on metallic surfaces represent
crucial steps to carburization of metal. Here, we use density functional theory
total energy calculations with the climbing-image nudged elastic band method to
estimate the adsorption energies and dissociation barriers for different CO
coverages with surface supercells of different sizes. For the absorption of CO,
the contribution from van der Waals interaction in the computation of
adsorption parameters is found important in small systems with high
CO-coverages. The dissociation process involves carbon insertion into the Fe
surface causing a lattice deformation that requires a larger surface system for
unrestricted relaxation. We show that, in larger surface systems associated
with dilute CO-coverages, the dissociation barrier is significantly decreased.
The elastic deformation of the surface is generic and can potentially
applicable for all similar metal-hydrocarbon reactions and therefore a dilute
coverage is necessary for the simulation of these reactions as isolated
processes.Comment: 12 pages, 6 figures. Submitted to Journal of Applied Physic
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