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1.
Radiography (Lond) ; 30(3): 715-722, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38428195

RESUMO

INTRODUCTION: Ultrasound education varies greatly across European healthcare systems. This paper focuses on ultrasound academic education as a part of wider suite of surveys on radiographers working in ultrasound. The aim was to investigate sonography educational levels, methods of training, course duration and other factors in European Federation of Radiographers Societies (EFRS) member countries. METHOD: In 2019 an online survey was sent to the 38 EFRS member societies to distribute to higher education institutions within their own country. The survey was in English and contained different types of questions such as closed questions, free text options, and scale responses, to investigate sonography education including academic course types and duration, curriculum content, learning and teaching methods. RESULTS: A total of 45 responses were received, showing wide variation in the duration of training between the respective countries. Academic level 7 (part-time) ultrasound education was most frequently reported (n = 13), followed by direct entry ultrasound courses (n = 9) and bachelor's degree programmes at EQF level 6 (n = 7). The duration of part-time courses ranged from nine months up to four years. CONCLUSION: Sonography training and education varies among EFRS member countries ranging from short focused courses to postgraduate awards. Few countries offer sonography education leading to an award. The majority of clinical teaching and learning takes place in the learner's workplace. IMPLICATIONS FOR PRACTICE: High quality academic and clinical education for radiographers extending their role into ultrasound is important to ensure safe, effective sonography practice and good patient care.


Assuntos
Currículo , Ultrassonografia , Europa (Continente) , Humanos , Inquéritos e Questionários , Sociedades Médicas , Competência Clínica
2.
Radiography (Lond) ; 30(2): 483-491, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219390

RESUMO

INTRODUCTION: Research has been performed by sonographers (also known as ultrasound reporting radiographers) for many years for improving diagnosis of disease, developing new imaging approaches, and enhancing patient outcomes. Despite this, sonographers' perspectives on research have not been well studied. To understand the views of sonographers is essential, as they have an important role in the successful implementation of research outcomes during their daily work. The study aimed to explore sonographers' perspectives on research. METHODS: This cross-sectional online questionnaire was developed, and pilot tested, before distribution on social media platforms by the research group to sonographers or reporting radiographers in ultrasound worldwide. The questionnaire included 21-items. The link was open for 8 weeks in the spring of 2023. A mix of closed, open and scale questions were used. Informed consent was mandatory, and information about the study and anonymity was presented. RESULTS: A total of 165 sonographers participated in the questionnaire of which 66.1 % were from Europe (n = 109), 6.1 % from North America (n = 10), 0.6 % from South America (n = 1), 2.4 % from Asia (n = 4), 13.3 % from Africa (n = 22) and 11.5 % from Oceania (n = 19). A total of 32 % of the participants had performed research. Also, 68.5 % would like to become more involved in research. CONCLUSION: Most sonographers work in large hospitals, and half of them have obtained academic level 7 education. A limited number of sonographers have published peer reviewed papers. Many sonographers expressed an interest in research. This suggests a potential for future development of the sonographers' role in research. IMPLICATIONS FOR PRACTICE: The findings for this study provide insight that could be used to improve research practice for sonographers.


Assuntos
Pessoal Técnico de Saúde , Humanos , Estudos Transversais , Ultrassonografia , Inquéritos e Questionários , Europa (Continente)
3.
Opt Express ; 30(25): 44992-45007, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522911

RESUMO

Providing phase stable laser light is important to extend the interrogation time of optical clocks towards many seconds and thus achieve small statistical uncertainties. We report a laser system providing more than 50 µW phase-stabilized UV light at 267.4 nm for an aluminium ion optical clock. The light is generated by frequency-quadrupling a fibre laser at 1069.6 nm in two cascaded non-linear crystals, both in single-pass configuration. In the first stage, a 10 mm long PPLN waveguide crystal converts 1 W fundamental light to more than 0.2 W at 534.8 nm. In the following 50 mm long DKDP crystal, more than 50 µW of light at 267.4 nm are generated. An upper limit for the passive short-term phase stability has been measured by a beat-node measurement with an existing phase-stabilized quadrupling system employing the same source laser. The resulting fractional frequency instability of less than 5×10-17 after 1 s supports lifetime-limited probing of the 27Al+ clock transition, given a sufficiently stable laser source. A further improved stability of the fourth harmonic light is expected through interferometric path length stabilisation of the pump light by back-reflecting it through the entire setup and correcting for frequency deviations. The in-loop error signal indicates an electronically limited instability of 1 × 10-18 at 1 s.

4.
Phys Rev Lett ; 129(23): 235001, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36563203

RESUMO

Solids ablate under laser irradiation, but experiments have not previously characterized the initiation of this process at ultrarelativistic laser intensities. We present first measurements of bulk ion velocity distributions as ablation begins, captured as a function of depth via Doppler-shifted x-ray line emission from two viewing angles. Bayesian analysis indicates that bulk ions are either nearly stationary or flowing outward at the plasma sound speed. The measurements quantitatively constrain the laser-plasma ablation mechanism, suggesting that a steplike electrostatic potential structure drives solid disassembly.

5.
Rev Sci Instrum ; 93(10): 103527, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319349

RESUMO

A high-resolution x-ray spectrometer was coupled with an ultrafast x-ray streak camera to produce time-resolved line shape spectra measured from hot, solid-density plasmas. A Bragg crystal was placed near laser-produced plasma to maximize throughput; alignment tolerances were established by ray tracing. The streak camera produced single-shot, time-resolved spectra, heavily sloped due to photon time-of-flight differences, with sufficient reproducibility to accumulate photon statistics. The images are time-calibrated by the slope of streaked spectra and dewarped to generate spectra emitted at different times defined at the source. The streaked spectra demonstrate the evolution of spectral shoulders and other features on ps timescales, showing the feasibility of plasma parameter measurements on the rapid timescales necessary to study high-energy-density plasmas.

6.
Phys Rev Lett ; 128(18): 185002, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35594117

RESUMO

Evolution of the hot spot plasma conditions was measured using high-resolution x-ray spectroscopy at the National Ignition Facility. The capsules were filled with DD gas with trace levels of Kr and had either a high-density-carbon (HDC) ablator or a tungsten (W)-doped HDC ablator. Time-resolved measurement of the Kr Heß spectra, absolutely calibrated by a simultaneous time-integrated measurement, allows inference of the electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. By matching the calculated hot spot emission using a collisional-radiative code to experimental observations, the hot spot size and areal density are determined. These advanced spectroscopy techniques further reveal the effect of W dopant in the ablator on the hot spot parameters for their improved implosion performance.

7.
Radiography (Lond) ; 28(1): 31-38, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34391653

RESUMO

INTRODUCTION: Radiographers can elect to work within many different modalities, one being ultrasound. Within Europe there are differing opinions about how much of a role radiographers should take in relation to the ultrasound examination, particularly report writing. This paper provides findings exploring the radiographer's views on working within sonography. METHODS: In 2019 an electronic survey was disseminated to radiographer members by European Federation of Radiographer Societies (EFRS) national radiographer societies, following a pilot study. A mix of closed questions, free text, and scale responses aimed to investigate radiographers' practice, legal responsibilities, report writing, educational level and experiences of support and mentoring. RESULTS: Of 561 radiographers participating, most (92%) reported performing ultrasound scans. Challenges with legislation, medical protectionism and lack of high-quality education restricted other radiographers. On average, the respondents have practiced ultrasound for 13.5 years. A total of 60% had postgraduate education and carried out a wide range of examinations. A full interpretative report, including advice on further investigations is performed by 52%, whilst 22% provide a checklist or descriptive report. Over 55% of radiographers took legal responsibility for the examination and the majority had clear protocols, good mentoring and support in the workplace. Peer review of their work was less common. CONCLUSION: The result shows that in 21 (n = 25) countries radiographers perform ultrasound, however not without challenges. Educational levels range from no formal education or short courses to an MSc in ultrasound. Report writing practice differs across the EFRS countries responding to the survey, as does peer review to enhance skills and clinical practice. IMPLICATIONS FOR PRACTICE: National Radiographer societies could review findings to support campaigning for a change in legislation and improvements to educational offerings in ultrasound.


Assuntos
Pessoal Técnico de Saúde , Europa (Continente) , Humanos , Projetos Piloto , Inquéritos e Questionários , Ultrassonografia
8.
Phys Rev Lett ; 127(20): 205001, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860067

RESUMO

Heß spectral line shapes are important for diagnosing temperature and density in many dense plasmas. This work presents Heß line shapes measured with high spectral resolution from solid-density plasmas with minimized gradients. The line shapes show hallmark features of Stark broadening, including quantifiable redshifts and double-peaked structure with a significant dip between the peaks; these features are compared to models through a Markov chain Monte Carlo framework. Line shape theory using the dipole approximation can fit the width and peak separation of measured line shapes, but it cannot resolve an ambiguity between electron density n_{e} and ion temperature T_{i}, since both parameters influence the strength of quasistatic ion microfields. Here a line shape model employing a full Coulomb interaction for the electron broadening computes self-consistent line widths and redshifts through the monopole term; redshifts have different dependence on plasma parameters and thus resolve the n_{e}-T_{i} ambiguity. The measured line shapes indicate densities that are 80-100% of solid, identifying a regime of highly ionized but well-tamped plasma. This analysis also provides the first strong evidence that dense ions and electrons are not in thermal equilibrium, despite equilibration times much shorter than the duration of x-ray emission; cooler ions may arise from nonclassical thermalization rates or anomalous energy transport. The experimental platform and diagnostic technique constitute a promising new approach for studying ion-electron equilibration in dense plasmas.

9.
Rev Sci Instrum ; 92(9): 093904, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598494

RESUMO

A novel high-resolution x-ray spectrometer for point-like emission sources has been developed using a crystal shape having both a variable major and a variable minor radius of curvature. This variable-radii sinusoidal spiral spectrometer (VR-Spiral) allows three common spectrometer design goals to be achieved simultaneously: 1. reduction of aberrations and improved spectral (energy) resolution, 2. reduction of source size broadening, and 3. use of large crystals to improve total throughput. The VR-Spiral concept and its application to practical spectrometer design are described in detail. This concept is then used to design a spectrometer for an extreme extended x-ray absorption fine structure experiment at the National Ignition Facility looking at the Pb L3 absorption edge at 13.0352 keV. The expected performance of this VR-Spiral spectrometer, both in terms of energy resolution and spatial resolution, is evaluated through the use of a newly developed raytracing tool, xicsrt. Finally, the expected performance of the VR-Spiral concept is compared to that of spectrometers based on conventional toroidal and variable-radii toroidal crystal geometries showing a greatly improved energy resolution.

10.
Radiography (Lond) ; 27(4): 1185-1191, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34294506

RESUMO

INTRODUCTION: Variability in non-medical ultrasound practice across Europe has been highlighted in studies. Meanwhile, advanced practice in radiography has undergone rapid development in the United Kingdom (UK). This survey aimed to review results relating to extended role and advanced practice skills, motivation and job satisfaction from a wider survey of radiographers undertaking ultrasound examinations across the European Federation of Radiographer Societies' (EFRS) community. METHODS: Following a pilot study, a SurveyMonkey™ on-line questionnaire was disseminated to EFRS member societies to share with their members, and via social media platforms. Quantitative questions for this article related to extended and advanced practice skills, communication of results, job satisfaction, motivation and career development. Theme analysis was used to assess qualitative feedback concerning priorities for future developments within the ultrasound role. RESULTS: There were 561 responses, mainly from the UK, Ireland and Spain (81%). The majority (83.4%) of UK sonographers communicate findings to patients, compared with 27.1% in other EFRS countries. More engage with teaching (UK = 90.1%, non-UK 72.9%) compared with activities in the other advanced practice domains. The lowest involvement was the research domain, with only 33% actively involved in research. Radiographers were motivated to undertake ultrasound to develop their knowledge and skills and assume more responsibility. CONCLUSION: Wide variations in ultrasound practice were seen across respondent countries. Generally, radiographers are happy with their ultrasound roles, although priorities include legislation for the sonographer role, remuneration, respect or support from medical colleagues, high quality education and role progression opportunities. IMPLICATIONS FOR PRACTICE: The findings provide a better understanding of radiographer views which can assist radiographer societies and local teams to develop strategies to enhance advanced practice skills development and career prospects in ultrasound.


Assuntos
Pessoal Técnico de Saúde , Motivação , Humanos , Projetos Piloto , Inquéritos e Questionários , Ultrassonografia
11.
Rev Sci Instrum ; 92(5): 053102, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243250

RESUMO

We report the development of a high-resolution spectrometer for extended x-ray absorption fine structure (EXAFS) studies of materials under extreme conditions. A curved crystal and detector in the spectrometer are replaceable such that a single body is employed to perform EXAFS measurements at different x-ray energy intervals of interest. Two configurations have been implemented using toroidal crystals with Ge 311 reflection set to provide EXAFS at the Cu K-edge (energy range 8.9-9.8 keV) and Ge 400 reflection set to provide EXAFS at the Ta L3-edge (9.8-10.7 keV). Key performance characteristics of the spectrometer were found to be consistent with design parameters. The data generated at the National Ignition Facility have shown an ≃3 eV spectral resolution for the Cu K-edge configuration and ≃6 eV for the Ta L3-edge configuration.

12.
Rev Sci Instrum ; 92(4): 043531, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243385

RESUMO

This paper describes a new class of focusing crystal forms for the x-ray Bragg crystal spectroscopy of small, point-like, x-ray sources. These new crystal forms are designed with the aid of sinusoidal spirals, a family of curves, whose shapes are defined by only one parameter, which can assume any real value. The potential of the sinusoidal spirals for the design x-ray crystal spectrometers is demonstrated with the design of a toroidally bent crystal of varying major and minor radii for measurements of the extended x-ray absorption fine structure near the Ta-L3 absorption edge at the National Ignition Facility.

13.
Rev Sci Instrum ; 92(3): 033525, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820090

RESUMO

Fine-structure x-ray spectra have been measured from foils with embedded tracer layers at two laser facilities. A suite of layered foils with thin Ti tracers under varied tamper layers was studied at both the Titan and the ALEPH 400 nm laser facilities, where Ti Heα emission was recorded using a high-resolution Bragg crystal spectrometer. Several indicators of plasma parameters are examined in the spectra, including temperature- and density-dependent line ratios and line broadening from Stark and opacity effects. Spectra indicate that (1) the plasma density at ALEPH is significantly higher than at Titan and (2) the electron temperature is high for near-surface layers at both facilities but drops more quickly with depth at ALEPH. These inferences of plasma conditions are consistent with differing levels of temporal contrast at each laser facility.

14.
Radiography (Lond) ; 27(3): 761-767, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33658166

RESUMO

INTRODUCTION: Ultrasound is one of many areas of specialism for radiographers to develop their skills in. As part of a wider suite of surveys, the European Federation of Radiographer Societies (EFRS) wanted to investigate the extent and scope of practice for radiographers practising ultrasound across Europe. This report details the results of the initial survey, exploring the views of the EFRS countries' National Radiographer Societies. METHODS: An electronic survey was sent to representatives of the 43 national radiographer societies who were members of the EFRS. Questions asked about radiographer practice in ultrasound within individual countries, scope of the role, particularly report writing, in addition to investigating current ultrasound education, barriers and opinions on priorities for radiographer ultrasound practice. RESULTS: Forty individual responses were received, from a total of 27 countries, covering 62.8% of the EFRS member societies invited to participate. Radiologists or specialised medical practitioners performed ultrasound in the majority of countries. Radiographers practise ultrasound in 48% of countries and 11% have some limited involvement in ultrasound. Countries without radiographer engagement in ultrasound reported legislative issues or lack of acceptance from the medical professions (52%) and/or limited specific ultrasound education (39%) as predominant factors. In most countries where radiographers practise ultrasound, clinical reporting is a descriptive report or checklist approved by a medical doctor/radiologist. CONCLUSION: The results highlight the scope of practice and barriers faced in some EFRS countries to enabling radiographers to develop their skills and competencies in ultrasound. IMPLICATIONS FOR PRACTICE: Priorities for radiographer societies to assist in the development of ultrasound as a pathway for radiographer progression in countries, where it is not yet available, include education programmes, acceptance by medical professionals and changes to legislation.


Assuntos
Pessoal Técnico de Saúde , Radiologistas , Europa (Continente) , Humanos , Inquéritos e Questionários , Ultrassonografia
15.
Radiography (Lond) ; 27(2): 464-474, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33223416

RESUMO

INTRODUCTION: To investigate student clinical placement concerns and opinions, during the initial COVID-19 pandemic outbreak and to inform educational institution support planning. METHODS: Between mid-June to mid-July 2020, educational institutions from 12 countries were invited to participate in an online survey designed to gain student radiographer opinion from a wide geographical spread and countries with varying levels of COVID-19 cases. RESULTS: 1277 respondents participated, of these 592 had completed clinical placements during January to June 2020. Accommodation and cohabiting risks were identified as challenging, as was isolation from family, travel to clinical placements, and to a lesser extent childcare. Students stated they had been affected by the feeling of isolation and concerns about the virus whilst on placement. Overall 35.4% of all respondents were 'Not at all worried' about being a radiographer, however, 64.6% expressed varying levels of concern and individual domestic or health situations significantly impacted responses (p ≤ 0.05). Year 4 students and recent graduates were significantly more likely to be 'Not worried at all' compared to Year 2 and 3 students (p ≤ 0.05). The need for improved communication regarding clinical placements scheduling was identified as almost 50% of students on clinical placements between January to June 2020 identified the completion of assessments as challenging. Furthermore, only 66% of respondents with COVID-19 imaging experience stated being confident with personal protective equipment (PPE) use. CONCLUSION: Student radiographers identified key challenges which require consideration to ensure appropriate measures are in place to support their ongoing needs. Importantly PPE training is required before placement regardless of prior COVID-19 imaging experience. IMPLICATIONS FOR PRACTICE: As the next academic year commences, the study findings identify important matters to be considered by education institutions with responsibility for Radiography training and as students commence clinical placements during the on-going global COVID-19 pandemic.


Assuntos
Atitude do Pessoal de Saúde , COVID-19/epidemiologia , Estresse Ocupacional , Pandemias , Radiografia , Radiologia/educação , Estudantes de Medicina/psicologia , Adolescente , Adulto , Ansiedade , COVID-19/transmissão , Competência Clínica , Comunicação , Humanos , Controle de Infecções , Preceptoria , Fatores de Risco , SARS-CoV-2 , Adulto Jovem
16.
Phys Rev Lett ; 123(8): 080503, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491201

RESUMO

Magic states were introduced in the context of Clifford circuits as a resource that elevates classically simulatable computations to quantum universal capability, while maintaining the same gate set. Here we study magic states in the context of matchgate (MG) circuits, where the notion becomes more subtle, as MGs are subject to locality constraints. Nevertheless a similar picture of gate-gadget constructions applies, and we show that every pure fermionic state which is non-Gaussian, i.e., which cannot be generated by MGs from a computational basis state, is a magic state for MG computations. This result has significance for prospective quantum computing implementation in view of the fact that MG circuit evolutions coincide with the quantum physical evolution of noninteracting fermions.

17.
Ultrasonics ; 94: 285-291, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30177283

RESUMO

A new generation of speed of sound (SOS) test object is presented that is fully constructed using additive manufacturing processes with a 3D-printer. The object contains 2 compartments with thin filaments and tubes that can be filled with fluid substances. The filaments are located at equal distances to each other; the tubes have fixed diameters. Depending on the chosen fluids (e.g. water, glycerol-water, corn oil, salt water) and room temperature, the mismatch in distance or diameter depending on the SOS error has been measured using ultrasound imaging equipment. The velocity of the fluid could be calculated deductively with high accuracy (range of total error: 0.1-3.4%). The results show that 3D-printed objects or additive manufacturing techniques can be suitable to use as teaching test objects within skills labs.

18.
Rev Sci Instrum ; 89(10): 10F118, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399766

RESUMO

The here-described spectrometer was developed for the extended x-ray absorption fine structure spectroscopy of high-density plasmas at the National Ignition Facility. It employs as the Bragg reflecting element a new type of toroidally bent crystal with a constant and very large major radius R and a much smaller, locally varying, minor radius r. The focusing properties of this crystal and the experimental arrangement of the source and detector make it possible to (a) fulfill the conditions for a perfect imaging of an ideal point source for each wavelength, (b) obtain a high photon throughput, (c) obtain a high spectral resolution by eliminating the effects of source-size broadening, and (d) obtain a one-dimensional spatial resolution with a high magnification perpendicular to the main dispersion plane.

19.
Rev Sci Instrum ; 89(10): 10F125, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399848

RESUMO

A high resolution, Diagnostic Instrument Manipulator (DIM)-based x-ray Bragg crystal spectrometer has been calibrated for and deployed at the National Ignition Facility (NIF) to diagnose plasma conditions in ignition capsules near stagnation times. The spectrometer has two conical crystals in the Hall geometry focusing rays from the Kr Heα, Lyα, and Heß complexes onto a streak camera, with the physics objectives of measuring time-resolved electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. A third von Hámos crystal that time-integrates the Kr Heα, Heß and intervening energy range provides in situ calibration for the streak camera signals. The spectrometer has been absolutely calibrated using a microfocus x-ray source, an array of CCD and single-photon-counting detectors, and multiple K- and L-absorption edge filters at the Princeton Plasma Physics Laboratory (PPPL) x-ray laboratory. Measurements of the integrated reflectivity, energy range, and energy resolution for each crystal are discussed. These calibration data provide absolute x-ray signal levels for NIF measurements, enabling precise filter selection and comparisons to simulations.

20.
HNO ; 66(6): 438-446, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-29740678

RESUMO

Anterior skull base operations are complex surgical procedures that are performed to treat serious and complicated diseases. Despite significant advances in surgical techniques, complications are relatively frequent and can be serious. Endoscopic skull base surgery seems to be associated with less complications than open techniques. Different classifications aimed at categorizing these complications have been suggested, the use of which can be recommended when reporting complication rates. The most relevant and frequent complications of anterior skull base surgery are hemorrhage, cerebrospinal fluid (CSF) leak, meningitis, and cranial nerve injury. Careful planning, close interdisciplinary cooperation, the competence of the skull base center and its members, and rigorous quality management are decisive for the avoidance of complications. With respect to the frequency and the seriousness of the complications, their meticulous and complete discussion with the patient before obtaining informed consent plays a central role.


Assuntos
Procedimentos Neurocirúrgicos , Complicações Pós-Operatórias , Neoplasias da Base do Crânio , Vazamento de Líquido Cefalorraquidiano , Endoscopia , Humanos , Procedimentos Neurocirúrgicos/efeitos adversos , Estudos Retrospectivos , Base do Crânio , Neoplasias da Base do Crânio/cirurgia
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