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1.
Radiography (Lond) ; 30(4): 1219-1224, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38905766

RESUMO

INTRODUCTION: This paper presents motivational factors to engage, start a research project and pursue a research career. The study aimed to investigate radiographer's motivation for engaging in research. METHODS: Eight radiographers from Denmark with experience in research were interviewed in a 2-h focus group interview in October 2023. This qualitative approach was selected to allow the participants to discuss their opinions and values. The discussions were audio recorded and transcribed before the thematic analysis was performed. RESULTS: The analysis revealed six main themes: the importance of radiographic research, the importance of radiographers' participation in research, research radiographers' motivation, funding and participation in research projects, demotivation and difficulties, and facilitating radiographic research in the future. CONCLUSION: The participants were motivated by different factors. The participants found both research in radiography and radiographers' participation in research-related activities important, although they found lack of support from managers, funding, and time to be demotivational factors. IMPLICATION FOR PRACTICE: This study contributes to the limited literature on motivational factors for becoming a researcher within radiography.

2.
Radiography (Lond) ; 30(2): 651-658, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341986

RESUMO

INTRODUCTION: Social media (SoMe) is widely used as a communication platform in everyday life. Also, healthcare professionals have embraced SoMe as a communication tool for both peers and patients. It is becoming an interactive tool for discussing professionals' issues and a place where learning and education occur. This study explores the specific patterns of SoMe use for radiographers' in the Nordic countries. The aim of this survey was to investigate radiographers use of social platforms in a professional setting. METHODS: A 29-item survey was prepared, and pilot-tested. The survey was produced in Danish a language that all Nordic countries master. In general, most Nordic languages are very similar. The survey was distributed by online platforms such as Facebook, LinkedIn, Twitter/X, and also distributed by newsletters by the Norwegian and Danish national radiographers societies. All data was collected anonymously. An Ethical Research approval was obtained from the University of Southern Denmark. RESULTS: A total of 242 respondents completed the survey (Denmark n = 183, Norway n = 48, Sweden n = 8, and n = 3 from other Scandinavian countries). The respondents included 186 females, 52 males and four were undisclosed. On average, the respondents spent approximately 2 h and 23 min daily on SoMe, with 27 min specifically dedicated to content relevant to radiographers. Facebook was the preferred platform with 93 % (n = 226). A total of 5.4 % (n = 13) respondents had experienced contact from patients and/or next of kin, while 92 % (n = 222) reported no such interactions and 2.9 % (n = 7) were undisclosed. A total of 52.8 % (n = 128) used SoMe in relation to courses, conferences, or online meetings. This shows that time spent on content relevant to radiographers imply that SoMe can be a relevant tool for reaching radiographers. CONCLUSION: The survey demonstrates radiographers' use of SoMe for personal and professional interest, with Facebook as the preferred social media platform. SoMe were mostly used during courses, conferences, or online meetings with half of the respondent reported using SoMe platforms during working hours. These results underscore the untapped potential of SoMe in professional healthcare settings. Additionally, the study offers insight into current practices, facilitating comparisons to identify trends in SoMe usage within the radiographer community. IMPLICATIONS FOR PRACTICE: The findings advocate for the strategic use of SoMe by radiographers', emphasizing professional networking and knowledge sharing. However, clear guidelines are necessary to ensure patient confidentiality and data security in these digital interactions.


Assuntos
Mídias Sociais , Masculino , Feminino , Humanos , Pessoal Técnico de Saúde , Pessoal de Saúde , Noruega , Suécia
3.
Radiography (Lond) ; 28(2): 426-432, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34556417

RESUMO

INTRODUCTION: To design a custom phantom of the coronary arteries to optimize CT coronary angiography (CCTA) protocols. METHODS: Characteristics of the left and right coronary arteries (mean Hounsfield Unit (HU) values and diameters) were collected from consecutive CCTA examinations (n = 43). Four different materials (two mixtures of glycerine, gelatine and water, pig hearts, Ecoflex™ silicone) were scanned inside a Lungman phantom using the CCTA protocol to find the closest model to in vivo data. A 3D printed model of the coronary artery tree was created using CCTA data by exporting a CT volume rendering into Autodesk Meshmixer™ software. The model was placed in an acid bath for 5 h, then covered in Ecoflex™, which was removed after drying. Both the Ecoflex™ and pig heart were later filled with a mixture of contrast (Visipaque 320 mg I/ml), NaCl and gelatin and scanned with different levels of tube current and iterative reconstruction (ASiR-V). Objective (HU, noise and size (vessel diameter) and subjective analysis were performed on all scans. RESULTS: The gelatine mixtures had HU values of 130 and 129, Ecoflex™ 65 and the pig heart 56. At the different mA/ASiR-V levels the contrast filled Ecoflex™ had a mean HU 318 ± 4, noise 47±7HU and diameter of 4.4 mm. The pig heart had a mean HU of 209 ± 5, noise 38±4HU and a diameter of 4.4 mm. With increasing iterative reconstruction level the visualisation of the pig heart arteries decreased so no measurements could be performed. CONCLUSION: The use of a 3D printed model of the arteries and casting with the Ecoflex™ silicone is the most suitable solution for a custom-designed phantom. IMPLICATIONS FOR PRACTICE: Custom designed phantoms using 3D printing technology enable cost effective optimisation of CT protocols.


Assuntos
Vasos Coronários , Tomografia Computadorizada por Raios X , Animais , Vasos Coronários/diagnóstico por imagem , Humanos , Impressão Tridimensional , Doses de Radiação , Silicones , Suínos , Tomografia Computadorizada por Raios X/métodos
4.
Radiography (Lond) ; 27(1): 1-7, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32402706

RESUMO

INTRODUCTION: Organ-based tube current modulation (OBTCM) is designed for anterior dose reduction in Computed Tomography (CT). The purpose was to assess dose reduction capability in chest CT using three organ dose modulation systems at different kVp settings. Furthermore, noise, diagnostic image quality and tumour detection was assessed. METHODS: A Lungman phantom was scanned with and without OBTCM at 80-135/140 kVp using three CT scanners; Canon Aquillion Prime, GE Revolution CT and Siemens Somatom Flash. Thermo-luminescent dosimeters were attached to the phantom surface and all scans were repeated five times. Image noise was measured in three ROIs at the level of the carina. Three observers visually scored the images using a fivestep scale. A Wilcoxon Signed-Rank test was used for statistical analysis of differences. RESULTS: Using the GE revolution CT scanner, dose reductions between 1.10 mSv (12%) and 1.56 mSv (24%) (p < 0.01) were found in the anterior segment and no differences posteriorly and laterally. Total dose reductions between 0.64 (8%) and 0.91 mSv (13%) were found across kVp levels (p < 0.00001). Maximum noise increase with OBTCM was 0.8 HU. With the Canon system, anterior dose reductions of 6-10% and total dose reduction of 0.74-0.76 mSv across kVp levels (p < 0.001) were found with a maximum noise increase of 1.1 HU. For the Siemens system, dose increased by 22-51% anteriorly; except at 100 kVp where no dose difference was found. Noise decreased by 1 to 1.5 HU. CONCLUSION: Organ based tube current modulation is capable of anterior and total dose reduction with minimal loss of image quality in vendors that do not increase posterior dose. IMPLICATIONS FOR PRACTICE: This research highlights the importance of being familiar with dose reduction technologies.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Imagens de Fantasmas , Doses de Radiação
5.
Artigo em Inglês | MEDLINE | ID: mdl-19766531

RESUMO

We have demonstrated the usefulness of the archetypical solid state-technique of Mössbauer spectroscopy to non-invasive studies of the redox and coordination chemistry of iron in a natural hyperacid solution from Iron Mountain, CA. Suitable fast cooling conditions were used to prepare a glass from the natural solution. Measurements of spectra at low temperatures (6 and 15K) and in large external magnetic fields (6T) of the glassy, frozen solution revealed a behaviour characteristic of slow paramagnetic relaxation of ferric ions. Analyses of the spectral components are in good agreement with dominance of hexaaquairon(III) ions.


Assuntos
Ferro/química , Espectroscopia de Mossbauer , Água/química , Ácidos/química , Oxirredução
6.
J Phys Condens Matter ; 21(1): 016007, 2009 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21817244

RESUMO

Mössbauer spectra of antiferromagnetic goethite (α-FeOOH) particles usually show an asymmetric line broadening, which increases with increasing temperature, although the magnetic anisotropy is expected to be so large that magnetic relaxation effects should be negligible. By use of high resolution transmission electron microscopy we have studied a sample of goethite particles and have found that the particles contain many defects such as low angle grain boundaries, in accordance with previous studies of other samples of goethite particles. Such defects can result in a magnetic mismatch at the grain boundaries between nanometer-sized grains, leading to a weakened magnetic coupling between the grains. We show that the Mössbauer data of goethite can be explained by fluctuations of the sublattice magnetization directions in such weakly coupled grains. It is likely that the influence of defects such as low angle grain boundaries also plays a role with regards to the magnetic properties in other antiferromagnetic nanograin systems. We discuss the results in relation to Mössbauer studies of α-Fe(2)O(3) and α-Fe(2)O(3)/NiO nanoparticles.

7.
J Phys Chem B ; 112(29): 8507-13, 2008 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-18590326

RESUMO

The magnetic properties of cobalt ferrite nanoparticles dispersed in a silica matrix in samples with different concentrations (5 and 10 wt% CoFe2O 4) and same particle size (3 nm) were studied by magnetization, DC and AC susceptibility, and Mossbauer spectroscopy measurements. The results indicate that the particles are very weakly interacting. The magnetic properties (saturation magnetization, anisotropy constant, and spin-canting) are discussed in relation to the cation distribution.

8.
Nanotechnology ; 19(31): 315712, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21828804

RESUMO

Experimental data for antiferromagnetic nanoparticles are often analyzed as if the particles were ferromagnetic. However, due to the volume dependence of the magnetization resulting from uncompensated spins, such analysis will yield erroneous results. This is demonstrated as we analyze ac and dc magnetization data as well as Mössbauer spectra obtained for ferritin. The values of the median energy barrier obtained from the different data are in very close agreement when a distribution of volumes and a volume dependence of the magnetization are taken into account. However, when the volume dependence of the magnetization is neglected, erroneous values of the anisotropy energy barrier and the attempt time τ(0) are obtained.

9.
J Chem Phys ; 125(16): 164714, 2006 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-17092127

RESUMO

The magnetic properties of cobalt ferrite-silica nanocomposites with different concentrations (15, 30, and 50 wt %) and sizes (7, 16, and 28 nm) of ferrite particles have been studied by static magnetization measurements and Mossbauer spectroscopy. The results indicate a superparamagnetic behavior of the nanoparticles, with weak interactions slightly increasing with the cobalt ferrite content and with the particle size. From high-field Mossbauer spectra at low temperatures, the cationic distribution and the degree of spin canting have been estimated and both parameters are only slightly dependent on the particle size. The magnetic anisotropy constant increases with decreasing particle size, but in contrast to many other systems, the cobalt ferrite nanoparticles are found to have an anisotropy constant that is smaller than the bulk value. This can be explained by the distribution of the cations. The weak dependence of spin canting degree on particle size indicates that the spin canting is not simply a surface phenomenon but also occurs in the interiors of the particles.


Assuntos
Cobalto/química , Compostos Férricos/química , Magnetismo , Nanocompostos/química , Transição de Fase , Dióxido de Silício/química , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura , Tamanho da Partícula , Espectrofotometria , Temperatura , Termodinâmica
10.
J Phys Condens Matter ; 18(17): 4161-75, 2006 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-21690771

RESUMO

We have studied the magnetic properties of (57)Fe-doped NiO nanoparticles using Mössbauer spectroscopy and magnetization measurements. Two samples with different degrees of interparticle interaction were studied. In both samples the particles were characterized by high-resolution transmission electron microscopy and x-ray diffraction and found to be plate-shaped. Computer simulations showed that high-field Mössbauer data are very sensitive to the size of the uncompensated magnetic moment. From analyses of the Mössbauer spectra we have estimated that the size of the uncompensated magnetic moment is in accordance with a model based on random occupation of surface sites. The analyses of the magnetization data gave larger magnetic moments, but the difference can be explained by the different sensitivity of the two methods to a particle size distribution and by interactions between the particles, which may have a strong influence on the moments estimated from magnetization data.

12.
Phys Rev Lett ; 72(20): 3278-3281, 1994 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-10056152
13.
Phys Rev Lett ; 72(2): 282-285, 1994 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-10056105
14.
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