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1.
JMIR Res Protoc ; 11(7): e36780, 2022 Jul 06.
Article in English | MEDLINE | ID: mdl-35793124

ABSTRACT

BACKGROUND: There are sparse data on the long-term and late effects of hematopoietic cell transplantation (HCT) for sickle cell disease (SCD). OBJECTIVE: This study aims to establish an international registry of long-term outcomes post-HCT for SCD and demonstrate the feasibility of recruitment at a single site in the United States. METHODS: The Sickle Cell Transplantation Evaluation of Long-Term and Late Effects Registry (STELLAR) was designed to enroll patients with SCD ≥1 year post-HCT, their siblings without SCD, and nontransplanted controls with SCD to collect web-based participant self-reports of health status and practices by using the Bone Marrow Transplant Survivor Study (BMTSS) surveys, health-related quality of life (HRQOL) using the Patient-Reported Outcomes Measurement Information System (PROMIS) Pediatric Profile-25 or Pediatric Profile-29 survey, chronic graft-versus-host disease (cGVHD) using the symptom scale survey, daily pain using an electronic pain diary, the economic impact of HCT using the financial hardship survey, sexual function using the PROMIS Sexual Function SexFSv2.0 survey, and economic productivity using the American Time Use Survey (ATUS). We also piloted retrieval of clinical data previously submitted to the Center for International Blood and Marrow Transplant Research (CIBMTR); recorded demographics, height, weight, blood pressure, waist and hip circumferences, timed up and go (TUG) test, and handgrip test; and obtained blood for metabolic screening, gonadal function, fertility potential, and biorepository of plasma, serum, RNA, and DNA. RESULTS: Of 100 eligible post-HCT patients, we enrolled 72 (72%) participants aged 9-38 (median 17) years. We also enrolled 19 siblings aged 5-32 (median 10) years and 28 nontransplanted controls with SCD aged 4-46 (median 22) years. Of the total 119 participants, 73 (61%) completed 85 sets of surveys and 41 (35%) contributed samples to the biorepository. We completed ATUS interviews of 28 (24%) participants. We successfully piloted retrieval of data submitted to the CIBMTR and expanded recruitment to multiple sites in the United States, Canada, the United Kingdom, and Nigeria. CONCLUSIONS: It is feasible to recruit subjects and conduct study procedures for STELLAR in order to determine the long-term and late effects of HCT for SCD. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36780.

2.
Materials (Basel) ; 14(11)2021 May 31.
Article in English | MEDLINE | ID: mdl-34072987

ABSTRACT

The microstructure directly influences the subsequent mechanical properties of materials. In the manufactured parts, the elaboration processes set the microstructure features such as phase types or the characteristics of defects and grains. In this light, this article aims to understand the evolution of the microstructure during the directed energy deposition (DED) manufacturing process of Ti6Al4V alloy. It sets out a new concept of time-phase transformation-block (TTB). This innovative segmentation of the temperature history in different blocks allows us to correlate the thermal histories computed by a 3D finite element (FE) thermal model and the final microstructure of a multilayered Ti6Al4V alloy obtained from the DED process. As a first step, a review of the state of the art on mechanisms that trigger solid-phase transformations of Ti6Al4V alloy is carried out. This shows the inadequacy of the current kinetic models to predict microstructure evolution during DED as multiple values are reported for transformation start temperatures. Secondly, a 3D finite element (FE) thermal simulation is developed and its results are validated against a Ti6Al4V part representative of repair technique using a DED process. The building strategy promotes the heat accumulation and the part exhibits heterogeneity of hardness and of the nature and the number of phases. Within the generated thermal field history, three points of interest (POI) representative of different microstructures are selected. An in-depth analysis of the thermal curves enables distinguishing solid-phase transformations according to their diffusive or displacive mechanisms. Coupled with the state of the art, this analysis highlights both the variable character of the critical points of transformations, and the different phase transformation mechanisms activated depending on the temperature value and on the heating or cooling rate. The validation of this approach is achieved by means of a thorough qualitative description of the evolution of the microstructure at each of the POI during DED process. The new TTB concept is thus shown to provide a flowchart basis to predict the final microstructure based on FE temperature fields.

3.
Sci Rep ; 10(1): 22285, 2020 Dec 17.
Article in English | MEDLINE | ID: mdl-33335195

ABSTRACT

In polyjet printing photopolymer droplets are deposited on a build tray, leveled off by a roller and cured by UV light. This technique is attractive to fabricate heterogeneous architectures combining compliant and stiff constituents. Considering the layer-by-layer nature, interfaces between different photopolymers can be formed either before or after UV curing. We analyzed the properties of interfaces in 3D printed composites combining experiments with computer simulations. To investigate photopolymer blending, we characterized the mechanical properties of the so-called digital materials, obtained by mixing compliant and stiff voxels according to different volume fractions. We then used nanoindentation to measure the spatial variation in mechanical properties across bimaterial interfaces at the micrometer level. Finally, to characterize the impact of finite-size interfaces, we fabricated and tested composites having compliant and stiff layers alternating along different directions. We found that interfaces formed by deposition after curing were sharp whereas those formed before curing showed blending of the two materials over a length scale bigger than individual droplet size. We found structural and functional differences of the layered composites depending on the printing orientation and corresponding interface characteristics, which influenced deformation mechanisms. With the wide dissemination of 3D printing techniques, our results should be considered in the development of architectured materials with tailored interfaces between building blocks.

4.
Pflege ; 32(1): 17-29, 2019 Feb.
Article in German | MEDLINE | ID: mdl-30430913

ABSTRACT

Hospital nurses' perspective on academic nursing education: a cross-sectional study in hospitals in the northwestern part of Germany Abstract. BACKGROUND: Currently, there is an increasing need for highly qualified nurses in Germany. Against this background, an academic nursing education is frequently demanded in order to meet the high level of competences nurses must fulfil. AIM: This cross-sectional study aimed to explore nurses' attitudes towards academic nursing education as well as their self-reported scientific competences. METHODS: Based on a standardized questionnaire, we surveyed 547 hospital nurses from six different hospitals in the northwestern part of Germany. By means of a bivariate analysis and two multivariate regression models, we examined the influence of the independent variables "professional position", "degree of academic education", "age" and "gender" on the dependent variables "attitude towards academic nursing education" and "scientific competences". The multivariate analysis included three co-variates analysing different ways of support of academic nursing education within the hospitals. RESULTS: Especially nursing staff who has completed a study programme, is currently studying or hold executive positions has a more positive attitude towards academic education than its colleagues have. Moreover, opportunities for advancement within the hospitals influence the staff's attitude positively. With regard to the assessment of scientific competences, the analysis shows that a completed or currently conducted study programme as well as an executive position have a positive influence. In addition, male nursing staff, young nursing staff and staff with access to scientific articles assess their scientific skills more positively than their colleagues do. CONCLUSIONS: The attitudes towards academic education are still heterogeneous and influenced by different factors. Accordingly, the worth of academic education needs to be demonstrated.


Subject(s)
Attitude of Health Personnel , Education, Nursing , Nursing Staff, Hospital/psychology , Cross-Sectional Studies , Female , Germany , Humans , Male , Nursing Education Research , Nursing Staff, Hospital/statistics & numerical data , Surveys and Questionnaires
5.
J Thorac Oncol ; 10(3): 454-61, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25376514

ABSTRACT

INTRODUCTION: Despite the lack of randomized evidence, stereotactic body radiotherapy (SBRT) is being accepted as superior to conventional radiotherapy for patients with T1-2N0 non-small-cell lung cancer in the periphery of the lung and unfit or unwilling to undergo surgery. To introduce SBRT in a system of coverage with evidence development, a correct financing had to be determined. METHODS: A time-driven activity-based costing model for radiotherapy was developed. Resource cost calculation of all radiotherapy treatments, standard and innovative, was conducted in 10 Belgian radiotherapy centers in the second half of 2012. RESULTS: The average cost of lung SBRT across the 10 centers (6221&OV0556;) is in the range of the average costs of standard fractionated 3D-conformal radiotherapy (5919&OV0556;) and intensity-modulated radiotherapy (7379&OV0556;) for lung cancer. Hypofractionated 3D-conformal radiotherapy and intensity-modulated radiotherapy schemes are less costly (3993&OV0556; respectively 4730&OV0556;). The SBRT cost increases with the number of fractions and is highly dependent of personnel and equipment use. SBRT cost varies more by centre than conventional radiotherapy cost, reflecting different technologies, stages in the learning curve and a lack of clear guidance in this field. CONCLUSIONS: Time-driven activity-based costing of radiotherapy is feasible in a multicentre setup, resulting in real-life resource costs that can form the basis for correct reimbursement schemes, supporting an early yet controlled introduction of innovative radiotherapy techniques in clinical practice.


Subject(s)
Cost-Benefit Analysis , Lung Neoplasms/economics , Lung Neoplasms/surgery , Radiosurgery/economics , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated/economics , Follow-Up Studies , Humans , Prognosis
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