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1.
Int J Food Microbiol ; 301: 27-33, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31082697

RESUMO

Pre-chilling leads to a temperature decline of the pre-rigor muscle of poultry carcasses, and a reduction of the initial bacterial load may occur. Both ultrasound (US) and slightly acidic electrolyzed water (SAEW) have been used alone in the meat industry for the manufacture of emulsions, pasteurization, and prevention of bacteria growth. However, the impact of the combination of these technologies during the pre-chilling of chicken carcasses has not been evaluated. In this study, breast chicken cylinders (CBCs) were pre-chilled for 10 min at 10 °C using SAEW and different US frequencies (25 and 130 kHz). The microbiological characteristics, lipid and protein oxidation, shear force, and anaerobic glycolysis were evaluated. The US + SAEW combination led to an effective reduction (P < 0.05) of enterobacteria, mesophilic bacteria, lactic acid bacteria, and psychrotrophic bacteria, while the lipid and protein oxidation, shear force, anaerobic glycolysis, and muscle structure were not affected (P > 0.05). Therefore, the combination of these technologies may be promising in the pre-chilling stage of chicken carcasses.


Assuntos
Ácidos/farmacologia , Carga Bacteriana/efeitos dos fármacos , Microbiologia de Alimentos/métodos , Carne/microbiologia , Ultrassom/normas , Animais , Galinhas/microbiologia , Temperatura Baixa , Eletrólise , Água/química
2.
Ostomy Wound Manage ; 64(9): 39-46, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30256750

RESUMO

Management of diabetes-related foot ulcers often involves debridement of devitalized tissue, but evidence regarding the most effective debridement method is limited. PURPOSE: A systematic review was conducted to determine the effectiveness of nonsurgical sharp debridement (NSSD) versus low-frequency ultrasonic debridement (LFUD) for diabetes-related foot ulceration in adults. METHOD: Published studies (earliest date available to April 2017) comparing healing outcomes of LFUD- and NSSD-treated foot ulcers in adults were considered. The quality of publications that met inclusion criteria were assessed using the PEDro scale, and a meta-analysis was undertaken to compare percentage healed and percentage of ulcer size reduction. RESULTS: Of the 259 publications identified, 4 met the inclusion criteria but 2 of the 4 did not contain sufficient patient outcomes details for meta-analysis, leaving a sample size of 173 patients. Outcome data for the 2 studies included percentage of ulcers healed between the 2 debridement methods. This difference was not significant (RR = 0.92; 95% CI = 0.76-1.11). The risk of bias for both studies was low. CONCLUSION: No difference in healing outcomes between NSSD and LFUD debridement of diabetic foot ulcers was found. Well-designed, controlled clinical studies are needed to address the current paucity of studies examining the efficacy and comparative effectiveness of debridement methods.


Assuntos
Desbridamento/normas , Pé Diabético/cirurgia , Ultrassom/normas , Adulto , Desbridamento/métodos , Diabetes Mellitus/enfermagem , Humanos , Cicatrização/fisiologia
3.
Med Educ ; 51(2): 196-206, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27943372

RESUMO

CONTEXT: Traditionally, trainees are instructed to practise with as few errors as possible during simulation-based training. However, transfer of learning may improve if trainees are encouraged to commit errors. The aim of this study was to assess the effects of error management instructions compared with error avoidance instructions during simulation-based ultrasound training. METHODS: Medical students (n = 60) with no prior ultrasound experience were randomised to error management training (EMT) (n = 32) or error avoidance training (EAT) (n = 28). The EMT group was instructed to deliberately make errors during training. The EAT group was instructed to follow the simulator instructions and to commit as few errors as possible. Training consisted of 3 hours of simulation-based ultrasound training focusing on fetal weight estimation. Simulation-based tests were administered before and after training. Transfer tests were performed on real patients 7-10 days after the completion of training. Primary outcomes were transfer test performance scores and diagnostic accuracy. Secondary outcomes included performance scores and diagnostic accuracy during the simulation-based pre- and post-tests. RESULTS: A total of 56 participants completed the study. On the transfer test, EMT group participants attained higher performance scores (mean score: 67.7%, 95% confidence interval [CI]: 62.4-72.9%) than EAT group members (mean score: 51.7%, 95% CI: 45.8-57.6%) (p < 0.001; Cohen's d = 1.1, 95% CI: 0.5-1.7). There was a moderate improvement in diagnostic accuracy in the EMT group compared with the EAT group (16.7%, 95% CI: 10.2-23.3% weight deviation versus 26.6%, 95% CI: 16.5-36.7% weight deviation [p = 0.082; Cohen's d = 0.46, 95% CI: -0.06 to 1.0]). No significant interaction effects between group and performance improvements between the pre- and post-tests were found in either performance scores (p = 0.25) or diagnostic accuracy (p = 0.09). CONCLUSIONS: The provision of error management instructions during simulation-based training improves the transfer of learning to the clinical setting compared with error avoidance instructions. Rather than teaching to avoid errors, the use of errors for learning should be explored further in medical education theory and practice.


Assuntos
Competência Clínica/normas , Educação de Graduação em Medicina/métodos , Estudantes de Medicina , Transferência de Experiência , Ultrassom/educação , Humanos , Aprendizagem , Prática Psicológica , Treinamento por Simulação/métodos , Ultrassom/normas
4.
Artigo em Inglês | MEDLINE | ID: mdl-27834633

RESUMO

In this paper, we report a calibration of acoustic trapping force of single-beam acoustic tweezer (SBAT) at ultrahigh frequency using micropipette aspiration. The acoustic trapping forces ( Ftrapping) and the trap stiffness on a 5- [Formula: see text] polystyrene microbead for a 110-MHz SBAT were measured against the known force generated from a micropipette. The trap stiffness ( k ), which represents Ftrapping corresponding to a displacement ( x ) of a microbead from the trap center, was measured and the results showed that a higher duty factor and excitation voltage lead to a stronger trapping force and trap stiffness for a given displacement. Since a precisely calibrated force generated from a micropipette is directly applied to the calculation of acoustic trapping force, the approach should be more flexible than those previously reported. In addition, with this method, precisely controlling the tip size of a micropipette within a few micrometers allows the possibility of calibrating the trapping force on an object of the size of a single cell. It not only helps better evaluate the trapping performance of SBAT as a tool of cell manipulation, but also helps develop SBAT as a useful tool for assessing cellular interactions.


Assuntos
Micromanipulação/métodos , Ultrassom/métodos , Engenharia Biomédica , Calibragem , Técnicas Citológicas/métodos , Técnicas Citológicas/normas , Micromanipulação/normas , Tamanho da Partícula , Ultrassom/normas
5.
Med Ultrason ; 18(3): 275-80, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27622401

RESUMO

AIM: To evaluate the usefulness of on-site education for clinical imaging evaluation using quality assurance (QA) testing of surveillance ultrasonography (US) for hepatocellular carcinoma (HCC). MATERIAL AND METHODS: Thirty-eight medical institutes underwent on-site education in 2012 for QA testing of clinical imaging evaluation of surveillance US for HCC. Failure rates and mean scores of clinical imaging evaluation for surveillance US of the 2011 survey, the 2012 survey after on-site education and the 2013 survey were compared. RESULTS: Failure rates and mean scores of the 2011 survey, the 2012 survey after education and the 2013 survey were 81.6%, 18.4%, 21.1% and 61.7, 82.7 and 74.6, respectively. Pair-wise analyses demonstrated that the failure rate of the 2011 survey was significantly larger compared to that observed in the other surveys. Mean score of the 2013 survey was worse than that of the 2012 survey after on-site education. CONCLUSIONS: On-site education positively impacts the failure rate and scores of clinical imaging evaluation of screening US for HCC. However, the impact may be reduced over time, and repeated, annual education might be necessary to maintain US quality.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Garantia da Qualidade dos Cuidados de Saúde/métodos , Ultrassom/educação , Ultrassonografia/normas , Humanos , Reprodutibilidade dos Testes , Ultrassom/normas
6.
Anesth Analg ; 123(6): 1372-1379, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27224934

RESUMO

Major surgical procedures often result in significant intra- and postoperative bleeding. The ability to identify the cause of the bleeding has the potential to reduce the transfusion of blood products and improve patient care. We present a novel device, the Quantra Hemostasis Analyzer, which has been designed for automated, rapid, near-patient monitoring of hemostasis. The Quantra is based on Sonic Estimation of Elasticity via Resonance Sonorheometry, a proprietary technology that uses ultrasound to measure clot time and clot stiffness from changes in viscoelastic properties of whole blood during coagulation. We present results of internal validation and analytical performance testing of the technology and demonstrate the ability to characterize the key functional components of hemostasis.


Assuntos
Testes de Coagulação Sanguínea/instrumentação , Cuidados Críticos , Hemostasia , Reologia/instrumentação , Ultrassom/instrumentação , Automação , Coagulação Sanguínea , Testes de Coagulação Sanguínea/normas , Viscosidade Sanguínea , Calibragem , Módulo de Elasticidade , Desenho de Equipamento , Hemorreologia , Humanos , Valor Preditivo dos Testes , Padrões de Referência , Reprodutibilidade dos Testes , Reologia/normas , Fatores de Tempo , Ultrassom/normas
7.
J Crit Care ; 30(5): 871-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122274

RESUMO

PURPOSE: Intensive care unit telemedicine (tele-ICU) uses audiovisual systems to remotely monitor and manage patients. Intensive care unit ultrasound can augment an otherwise limited bedside evaluation. To date, no studies have utilized tele-ICU technology to assess the quality and clinical use of real-time ultrasound images. We assessed whether tele-intensivists can instruct nonphysicians to obtain high-quality, clinically useful ultrasound images. METHODS: This prospective pilot evaluated the effectiveness of a brief educational session of nonphysician "ultrasonographers" on their ability to obtain ultrasound images (right internal jugular vein, bilateral lung apices and bases, cardiac subxiphoid view, bladder) with real-time tele-intensivist guidance. All ultrasound screen images were simultaneously photographed with a 2-way camera and saved on the ultrasound machine. The tele-intensivist assessed image quality, and an independent ultrasound expert rated their use in guiding clinical decisions. RESULTS: The intensivist rated the tele-ICU camera images as high quality (70/77, 91%) and suitable for guiding clinical decisions (74/77, 96%). Only bilateral lung apices demonstrated differences in quality and clinical use. All other images were rated noninferior and clinically useful. CONCLUSION: Tele-intensivists can guide minimally trained nonphysicians to obtain high-quality, clinically useful ultrasound images. For most anatomic sites, tele-ICU images are of similar quality to those acquired directly by ultrasound.


Assuntos
Cuidados Críticos/métodos , Telemedicina/métodos , Ultrassom/educação , Ultrassonografia/normas , Adulto , Feminino , Pessoal de Saúde/educação , Humanos , Unidades de Terapia Intensiva , Masculino , Projetos Piloto , Estudos Prospectivos , Ensino/métodos , Ultrassom/normas
8.
J Cataract Refract Surg ; 41(6): 1264-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26100958

RESUMO

PURPOSE: To determine the optimum power settings in micropulsed ultrasound (US). SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. DESIGN: Experimental study. METHODS: Pig lenses hardened to be comparable to dense human cataracts were cut into 2.0 mm cubes and removed using micropulsed longitudinal US with previously optimized settings (6 milliseconds on and 6 milliseconds off and using a 0.9 mm 30-degree beveled bent phaco tip). The aspiration was set at 40 mL/min and the vacuum level at 550 mm Hg. Twenty lens cubes were tested with the power set from 10% to 100% in increments of 10%. Primary outcome measures were efficiency time (time to lens removal) and chatter (number of times the lens fragment visibly bounced off the tip). RESULTS: Efficiency time decreased with increasing power. There was a correlation between power and efficiency time (R(2) = 0.41, P = .046), which was more substantial between 30% and 100% power (R(2) = 0.71, P = .004). The mean number of chatter events did not differ significantly between power settings (R(2) = 0.012, P = .1195). CONCLUSIONS: There was a 5-fold increase in efficiency between 10% power and 20% power, which likely indicates that there is a minimum power threshold for efficient breakup of the lens. Between 20% and 100% power, there was a linear, strong, and statistically significant improvement in efficiency in these lens fragments. In addition, with micropulsed US there was little chatter or microchatter throughout the power range. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Ondas de Choque de Alta Energia , Cristalino/cirurgia , Facoemulsificação/instrumentação , Ultrassom/normas , Animais , Duração da Cirurgia , Suínos
9.
Pesqui. vet. bras ; 35(3): 297-303, 03/2015. tab, graf
Artigo em Português | LILACS | ID: lil-751973

RESUMO

A ultrassonografia é um método de diagnóstico por imagem que permite a avaliação de diferentes órgãos e estruturas corpóreas de maneira não invasiva. No entanto, a avaliação subjetiva das imagens caracteriza um dos grandes entraves na utilização desta técnica de diagnóstico, havendo necessidade de mecanismos que minimizem a subjetividade do exame e a divergência na interpretação dos achados ultrassonográficos. Desta forma este trabalho objetivou caracterizar a ecogenicidade do parênquima e mediastino testicular de ovinos utilizando a técnica do histograma escala-cinza. Foram utilizados 30 animais divididos em três grupos de acordo com a faixa etária (FE): de três a seis meses (FE1), sete a 12 meses (FE2), 13 a 18 meses (FE3) e realizadas varreduras testiculares nos planos frontal, sagital e transversal, elaborando ao final um histograma a partir das imagens ultrassonográficas. Observou-se que tanto a ecogenicidade do parênquima quanto a do mediastino testicular aumentaram gradativamente com a progressão das idades dos animais, com média e desvio-padrão de 95,00±19,05 e 94,35±18,82 para a ecogenicidade do parênquima do antímero direito e esquerdo, respectivamente, e 127,95±12,97 para o mediastino direito e 126,59±11,78 para o esquerdo. A técnica do histograma escala-cinza demonstrou ser um método eficiente na determinação da ecogenicidade testicular, possibilitando o estabelecimento de padrões de normalidade que venham a auxiliar pesquisas futuras no monitoramento do desenvolvimento testicular bem como na detecção de patologias. Para a regimes exclusivos de criação extensiva, como na baixada maranhense, representa ferramenta valiosa para sua utilização em projetos sociais do Estado que atendem a agricultura familiar.


Ultrasound is a diagnostic imaging method that allows a no invasive evaluation of different organs and body structures. However, the personal evaluation of images is one of the major hampers in using this technique. In order to reduce this drawback, it is necessary to find out tools that can help diminish the divergence in the interpretation of sonographic findings. Therefore, this study aimed to identify features of the parenchyma's and mediastinum's testis of sheep echogenicity using the technique of gray scale histogram. 30 animals were divided into three groups according to age (FE): three to six months (FE1), seven to 12 months (FE2), 13 to 18 months (FE3). The testicular scans were performed in the frontal, sagital and transverse views, and the gray scale histograms were analyzed. It was observed that such parenchymal as the mediastinum testis echogenicity gradually increased with the aging of the animals, with mean and standard deviation of 95.00±19.05 and 94.35±18.82 for the echogenicity parenchyma of the right and left antimere, respectively, and 127.95±12.97 to 126.59±11.78, for the right and the left mediastinum. The technique of gray scale histogram was an efficient method for determination of testicular echogenicity, enabling the establishment of normal standards that may assist future research in monitoring testicular development as well as for detecting pathologies. For exclusive regimes of extensive farming, as the western lowland region of Maranhão, is a valuable tool for use in social projects of the State to attend the family farm.


Assuntos
Animais , Masculino , Interpretação de Imagem Assistida por Computador/métodos , Ovinos/anatomia & histologia , Testículo , Ultrassom/normas , Distribuição por Idade , Ultrassom/métodos
10.
Ultrasound Med Biol ; 41(4): 1079-94, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25701520

RESUMO

Calibration is essential in freehand 3-D ultrasound to find the spatial transformation from the image coordinates to the sensor coordinate system. Ease of use, simplicity, precision and accuracy are among the most important factors in ultrasound calibration, especially when aiming to make calibration more reliable for day-to-day clinical use. We introduce a new mathematical framework for the simple and popular single-wall calibration phantom with a plane equation pre-determination step and the use of differential measurements to obtain accurate measurements. The proposed method provides a novel solution for ultrasound calibration that is accurate and easy to perform. This method is applicable to both radiofrequency (RF) and B-mode data, and both linear and curvilinear transducers. For a linear L14-5 transducer, the point reconstruction accuracy (PRA) of reconstructing 370 points is 0.73 ± 0.23 mm using 100 RF images, whereas the triple N-wire PRA is 0.67 ± 0.20 mm using 100 B-mode images. For a curvilinear C5-2 transducer, the PRA using the proposed method is 0.86 ± 0.28 mm on 400 points using 100 RF images, whereas N-wire calibration gives a PRA of 0.80 ± 0.46 mm using 100 B-mode images. Therefore, the accuracy of the proposed variation of the single-wall method using RF data is practically similar to the N-wire method while offering a simpler phantom with no need for accurate design and construction.


Assuntos
Imageamento Tridimensional/normas , Imagens de Fantasmas , Ultrassom/normas , Algoritmos , Calibragem , Reprodutibilidade dos Testes
11.
Ultrasonics ; 57: 65-71, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25465962

RESUMO

The accuracy of density, reflection coefficient, and acoustic impedance determination via multiple reflection method was validated experimentally. The ternary system water-maltose-ethanol was used to execute a systematic, temperature dependent study over a wide range of densities and viscosities aiming an application as inline sensor in beverage industries. The validation results of the presented method and setup show root mean square errors of: 1.201E-3 g cm(-3) (±0.12%) density, 0.515E-3 (0.15%) reflection coefficient and 1.851E+3 kg s(-1) m(-2) (0.12%) specific acoustic impedance. The results of the diffraction corrected absorption showed an average standard deviation of only 0.12%. It was found that the absorption change shows a good correlation to concentration variations and may be useful for laboratory analysis of sufficiently pure liquids. The main part of the observed errors can be explained by the observed noise, temperature variation and the low signal resolution of 50 MHz. In particular, the poor signal-to-noise ratio of the second reflector echo was found to be a main accuracy limitation. Concerning the investigation of liquids the unstable properties of the reference material PMMA, due to hygroscopicity, were identified to be an additional, unpredictable source of uncertainty. While dimensional changes can be considered by adequate methodology, the impact of the time and temperature dependent water absorption on relevant reference properties like the buffer's sound velocity and density could not be considered and may explain part of the observed deviations.


Assuntos
Bebidas/análise , Misturas Complexas/análise , Indústria Alimentícia/métodos , Ultrassom/métodos , Ultrassom/normas , Acústica , Calibragem , Misturas Complexas/química , Impedância Elétrica , Etanol/análise , Etanol/química , Indústria Alimentícia/instrumentação , Ondas de Choque de Alta Energia , Maltose/análise , Maltose/química , Modelos Teóricos , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Soluções/química , Ultrassom/instrumentação , Viscosidade , Água/análise , Água/química
12.
ScientificWorldJournal ; 2014: 283024, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25243207

RESUMO

An ionic liquids based simultaneous ultrasonic and microwave assisted extraction (ILs-UMAE) method has been proposed for the extraction of rutin (RU), quercetin (QU), from velvetleaf leaves. The influential parameters of the ILs-UMAE were optimized by the single factor and the central composite design (CCD) experiments. A 2.00 M 1-butyl-3-methylimidazolium bromide ([C4mim]Br) was used as the experimental ionic liquid, extraction temperature 60°C, extraction time 12 min, liquid-solid ratio 32 mL/g, microwave power of 534 W, and a fixed ultrasonic power of 50 W. Compared to conventional heating reflux extraction (HRE), the RU and QU extraction yields obtained by ILs-UMAE were, respectively, 5.49 mg/g and 0.27 mg/g, which increased, respectively, 2.01-fold and 2.34-fold with the recoveries that were in the range of 97.62-102.36% for RU and 97.33-102.21% for QU with RSDs lower than 3.2% under the optimized UMAE conditions. In addition, the shorter extraction time was used in ILs-UMAE, compared with HRE. Therefore, ILs-UMAE was a rapid and an efficient method for the extraction of RU and QU from the leaves of velvetleaf.


Assuntos
Líquidos Iônicos/química , Malvaceae , Micro-Ondas , Quercetina/isolamento & purificação , Rutina/isolamento & purificação , Ultrassom/métodos , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Quercetina/química , Rutina/química , Ultrassom/normas
13.
Int J Food Microbiol ; 179: 18-23, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24704862

RESUMO

The efficacy of two leafy produce wash methods, the traditional cutting-before-washing process and a new washing-before-cutting method, on reduction of Escherichia coli O157:H7 inoculated on Iceberg lettuce was compared. The washing tests were conducted in a pilot-scale washer using combinations of water, chlorine, peroxyacetic acid, and ultrasound. The washing-before-cutting process recorded an E. coli O157:H7 count reduction 0.79-0.80 log10 CFU/g higher than that achieved with the cutting-before-washing process in treatments involving only a sanitizer. When ultrasound was applied to the washing-before-cutting process, a further improvement of 0.37-0.68 log10 CFU/g in microbial count reduction was obtained, reaching total reductions of 2.43 and 2.24 log10 CFU/g for chlorine and peroxyacetic acid washes, respectively.


Assuntos
Manipulação de Alimentos/normas , Microbiologia de Alimentos/métodos , Lactuca/microbiologia , Cloro/normas , Contagem de Colônia Microbiana , Desinfetantes/normas , Escherichia coli O157 , Ácido Peracético/normas , Temperatura , Ultrassom/normas , Água/normas
14.
J Cataract Refract Surg ; 40(5): 811-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24767913

RESUMO

PURPOSE: To evaluate 3 phacoemulsification tips of different sizes and determine which size is most efficient in lens fragment removal using 3 ultrasound (US) approaches. SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. DESIGN: Experimental study. METHODS: Porcine lens nuclei were formalin-soaked for 2 hours then divided into 2.0 mm cubes; 1.1 mm, 0.9 mm, and 0.7 mm phaco tips were used with torsional and micropulsed US. The 1.1 mm tips were unavailable for torsional US, so 0.9 mm and 0.7 mm tips were used. Efficiency (amount of time for lens removal) and chatter (number of lens-fragment repulsions from the tip) were determined. RESULTS: The mean phacoemulsification efficiency was highest with the 0.9 mm tip for all US variations. There were statistically significant differences between the 0.9 mm and 0.7 mm tips with micropulsed US (0.8 seconds ± 0.29 [SD] versus 1.4 ± 0.93 seconds; P=.0112) and transversal US (0.8 ± 0.17 seconds versus 1.4 ± 0.89 seconds; P=.0065). There was no significant difference between 0.9 mm and 0.7 mm tips with torsional US or between the 1.1 mm and 0.9 mm tips with micropulsed or transversal US; however, trends were identical, with 0.9 mm tips performing better than 0.7 mm and 1.1 mm tips. CONCLUSION: With all 3 systems, the 0.9 mm tip was most efficient, with the fewest outliers and smallest standard deviation. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Ondas de Choque de Alta Energia , Núcleo do Cristalino/cirurgia , Facoemulsificação/instrumentação , Ultrassom/normas , Animais , Facoemulsificação/métodos , Suínos
15.
Ultrasound Obstet Gynecol ; 43(4): 444-51, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24105723

RESUMO

OBJECTIVE: To explore the association between clinical training characteristics and trainees' level of confidence in performing ultrasound scans independently. METHODS: A cross-sectional e-survey was distributed to members of the national societies of junior obstetricians/gynecologists in Denmark, Sweden and Norway (n = 973). Multiple linear regression models were used to explore the effect that amount of time spent in specialized ultrasound units and clinical experience had on trainees' confidence in performing ultrasonography independently. Exploratory factor analysis was used to identify factors that contributed to trainees' confidence in performing ultrasonography. Trainees' ultrasound confidence was finally compared with their expected levels of performance. RESULTS: Of the 682 respondents (response rate 70.1%), 621 met the inclusion criteria. Clinical experience and time spent in specialized ultrasound units were predictors of trainees' confidence in performing ultrasonography independently (P < 0.001). Trainees required more than 24 months of clinical experience and 12-24 days of training in specialized ultrasound units in order to feel confident about performing transvaginal and transabdominal ultrasound scans independently. Three factors were related to ultrasound confidence: technical aspects, image perception and integration of scan into patient care. There were significant differences between trainees' level of confidence and their expected levels of performance (P < 0.001). CONCLUSIONS: Clinical experience and time spent in specialized ultrasound units were predictors of trainees' confidence in performing ultrasonography independently. Discrepancies between trainees' confidence and their expected levels of performance raised concerns about the adequacy of current ultrasound training programs.


Assuntos
Competência Clínica , Ginecologia , Obstetrícia , Ultrassom , Adulto , Atitude do Pessoal de Saúde , Competência Clínica/normas , Estudos Transversais , Dinamarca , Educação Médica Continuada , Educação de Pós-Graduação em Medicina , Feminino , Ginecologia/educação , Ginecologia/normas , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Obstetrícia/educação , Obstetrícia/normas , Gravidez , Inquéritos e Questionários , Suécia , Ultrassom/educação , Ultrassom/normas
16.
Hum Exp Toxicol ; 33(8): 863-72, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24275645

RESUMO

Aminophenol isomers (2-, 3-, and 4-aminophenols) are typically classified as industrial pollutants with genotoxic and mutagenic effects due to their easy penetration through the skin and membranes of human, animals, and plants. In the present study, a simple and efficient ultrasound-assisted emulsification microextraction procedure coupled with high-performance liquid chromatography with ultraviolet detector was developed for preconcentration and determination of these compounds in human fluid and environmental water samples. Effective parameters (such as type and volume of extraction solvent, pH and ionic strength of sample, and ultrasonication and centrifuging time) were investigated and optimized. Under optimum conditions (including sample volume: 5 mL; extraction solvent: chloroform, 80 µL; pH: 6.5; without salt addition; ultrasonication: 3.5 min; and centrifuging time: 3 min, 5000 rpm min(-1)), the enrichment factors and limits of detection were ranged from 42 to 51 and 0.028 to 0.112 µg mL(-1), respectively. Once optimized, analytical performance of the method was studied in terms of linearity (0.085-157 µg mL(-1), r (2) > 0.998), accuracy (recovery = 88.6- 101.7%), and precision (repeatability: intraday precision < 3.98%, and interday precision < 5.12%). Finally, applicability of the method was evaluated by the extraction and determination of these compounds in human urine, hair dye, and real water samples.


Assuntos
Aminofenóis/análise , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Tinturas para Cabelo/química , Microextração em Fase Líquida/métodos , Ultrassom/métodos , Poluentes Químicos da Água/análise , Aminofenóis/urina , Centrifugação , Clorofórmio/química , Cromatografia Líquida de Alta Pressão/normas , Monitoramento Ambiental/normas , Humanos , Concentração de Íons de Hidrogênio , Isomerismo , Limite de Detecção , Modelos Lineares , Microextração em Fase Líquida/normas , Concentração Osmolar , Reprodutibilidade dos Testes , Cloreto de Sódio/química , Solventes/química , Sonicação , Espectrofotometria Ultravioleta , Fatores de Tempo , Ultrassom/normas , Poluentes Químicos da Água/urina
18.
J Acoust Soc Am ; 132(2): 738-45, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22894196

RESUMO

A previously described laser ultrasonic technique known as spatially resolved acoustic spectroscopy (SRAS) can be used to image surface microstructure, using the local surface acoustic wave (SAW) velocity as a contrast mechanism. It is shown here that measuring the SAW velocity in multiple directions can be used to determine the crystallographic orientation of grains. The orientations are determined by fitting experimentally measured velocities to theoretical velocities. Using this technique the orientations of 12 nickel and 3 aluminum single crystal samples have been measured, and these are compared with x-ray Laue backreflection (LBR) measurements with good agreement. The root mean square difference between SRAS and LBR measurements in terms of an R-value is less than 4.1°. The influence of systematic errors in the SAW velocity determination due to instrument miscalibration, which affects the accurate determination of the planes, is discussed. SRAS has great potential for complementary measurements or even for replacing established orientation determination and imaging techniques.


Assuntos
Alumínio/química , Cristalografia , Níquel/química , Análise Espectral , Ultrassom , Calibragem , Cristalografia/instrumentação , Cristalografia/normas , Cristalografia por Raios X , Elasticidade , Lasers , Modelos Químicos , Estrutura Molecular , Movimento (Física) , Reprodutibilidade dos Testes , Análise Espectral/instrumentação , Análise Espectral/normas , Propriedades de Superfície , Ultrassom/instrumentação , Ultrassom/normas
19.
Rheumatology (Oxford) ; 51(11): 2013-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22843774

RESUMO

OBJECTIVE: To assess the interobserver reliability between sonographers with different levels of experience in detecting inflammatory and structural damage abnormalities in patients with knee OA. METHODS: After achieving consensus on definitions and scanning protocols, three ultrasonographers with different levels of experience in musculoskeletal US examined the knees of nine patients with OA. US examinations were conducted with independent blinded evaluations of inflammatory (joint effusion, synovial hypertrophy, power Doppler signal, Baker's cysts) and structural (osteophytes, cortical bone irregularities, femoral hyaline cartilage abnormalities, protrusion of the medial meniscus) lesions. All abnormalities were scored by applying a dichotomous scale (0-1). In addition, at each knee joint site global scores for joint inflammation, cortical bone abnormalities and cartilage damage were calculated by summing the single-lesion scores. Reliability was assessed using kappa (κ) coefficients. RESULTS: Seventeen knees were examined. Inflammatory abnormalities were observed with moderate to very good agreement (κ = 0.55-0.88) between the observers. From fair to very good agreement (κ = 0.31-0.82) was registered between sonographers for structural damage lesions. The overall κ was 0.716 for junior and 0.571 for beginner sonographers comparing their findings with those of senior sonographers. CONCLUSION: This represents the first ultrasonographic study focusing on the analysis of interobserver reliability between sonographers with different levels of experience in demonstrating inflammatory and structural abnormalities in knee OA. Globally, even considering some variable results that were mainly obtained by the evaluation of single components of bone involvement, US offered a reliable assessment of a wide set of abnormalities in knee OA.


Assuntos
Competência Clínica/normas , Osteoartrite do Joelho/diagnóstico por imagem , Ultrassom/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Musculoesquelética/etiologia , Variações Dependentes do Observador , Medição da Dor , Ultrassonografia
20.
J Cataract Refract Surg ; 38(6): 1065-71, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22624907

RESUMO

PURPOSE: To compare efficiency and chatter of Infiniti Ozil with and without Intelligent Phacoemulsification (IP) and the Signature Ellips with and without FX. SETTING: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. DESIGN: Experimental study. METHODS: Brunescent 2.0 mm human lens cubes were created by an instrument devised for this study. Cubes were tested (10 per test) for time of particle removal (efficiency) and for the number of times the lens particle bounced off the tip (chatter) at 300 mm Hg and 550 mm Hg, 50% and 100% power, and 50% and 100% amplitudes (amplitude for Ozil only). RESULTS: Of the ultrasound settings, efficiency varied from a mean of 3.3 seconds ± 1.4 (SD) to 50.4 ± 11.7 seconds and chatter from 0.0 to 52.0 ± 16.7 bounces per run. The Ozil-IP was generally more efficient than the Ozil and the Ellips FX more efficient than the Ellips. At optimized values, the Ozil-IP and Ellips-FX were similar. In general, efficiency and chatter were better at 550 mm Hg and at 50% power. The amplitude effect was complex. Efficiency closely correlated with chatter (Pearson r(2) = .31, P<.0001). CONCLUSIONS: Objective comparison of phacoemulsification efficiency and chatter found that optimized Ozil-IP and Ellips-FX were similar in both parameters and in general, both performed better than preceding technology. The study parameters can significantly affect efficiency and chatter, which strongly correlate with each other.


Assuntos
Catarata/patologia , Ondas de Choque de Alta Energia , Cristalino/cirurgia , Facoemulsificação/instrumentação , Ultrassom/normas , Humanos , Cristalino/química , Cristalino/patologia , Facoemulsificação/normas
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