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1.
Waste Manag ; 157: 269-278, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36580882

RESUMO

The problem of waste generation has grown because of the need to extract natural resources, obtain materials, and consume energy to meet current societal needs. Many studies have been conducted worldwide in favor of technological solutions for the valorization of industrial waste (IW) but few discussed relevant data for effective recovery. In this study, a case study of ceramic shell waste (CSW) was performed using, for the first time, a waste valorization system based on the classification, potentiality, quantity/viability, and applicability criteria (CPQvA) in a specific region (Brazil). CPQvA is a multicriteria decision-making system that acts as a guide to help managers and researchers connect the potential of IW with the feasibility of its application in a product or another process. Using the proposed systematic criteria, it was possible to demonstrate similarities and differences in waste applications. Thirteen possible products made from CSW were analyzed based on all the parameters of CPQvA. Ceramic filters and refractory aggregates were the most viable products. Creating public policies that encourage the use of waste as a raw material could make the precision casting industry process cleaner and the economy more circular.


Assuntos
Cerâmica , Gerenciamento de Resíduos , Resíduos Industriais , Política Pública , Brasil
2.
Eur Radiol ; 30(1): 487-500, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31359122

RESUMO

PURPOSE: To assess the dose performance in terms of image quality of filtered back projection (FBP) and two generations of iterative reconstruction (IR) algorithms developed by the most common CT vendors. MATERIALS AND METHODS: We used four CT systems equipped with a hybrid/statistical IR (H/SIR) and a full/partial/advanced model-based IR (MBIR) algorithms. Acquisitions were performed on an ACR phantom at five dose levels. Raw data were reconstructed using a standard soft tissue kernel for FBP and one iterative level of the two IR algorithm generations. The noise power spectrum (NPS) and the task-based transfer function (TTF) were computed. A detectability index (d') was computed to model the detection task of a large mass in the liver (large feature; 120 HU and 25-mm diameter) and a small calcification (small feature; 500 HU and 1.5-mm diameter). RESULTS: With H/SIR, the highest values of d' for both features were found for Siemens, then for Canon and the lowest values for Philips and GE. For the large feature, potential dose reductions with MBIR compared with H/SIR were - 35% for GE, - 62% for Philips, and - 13% for Siemens; for the small feature, corresponding reductions were - 45%, - 78%, and - 14%, respectively. With the Canon system, a potential dose reduction of - 32% was observed only for the small feature with MBIR compared with the H/SIR algorithm. For the large feature, the dose increased by 100%. CONCLUSION: This multivendor comparison of several versions of IR algorithms allowed to compare the different evolution within each vendor. The use of d' is highly adapted and robust for an optimization process. KEY POINTS: • The performance of four CT systems was evaluated by using imQuest software to assess noise characteristic, spatial resolution, and lesion detection. • Two task functions were defined to model the detection task of a large mass in the liver and a small calcification. • The advantage of task-based image quality assessment for radiologists is that it does not include only complicated metrics, but also clinically meaningful image quality.


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Calcinose/diagnóstico por imagem , Humanos , Hepatopatias/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imagens de Fantasmas , Garantia da Qualidade dos Cuidados de Saúde/métodos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Radiometria/métodos , Cintilografia , Software , Tomografia Computadorizada por Raios X/normas
3.
Diagn Interv Imaging ; 100(12): 763-770, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31473164

RESUMO

PURPOSE: To compare the noise-magnitude and noise-texture obtained using strong kernel across two generations of iterative reconstruction (IR) algorithms proposed by three manufacturers. MATERIALS AND METHODS: Five computed tomography (CT) systems equipped with two generations of IR algorithm (hybrid/statistical IR [H/SIR] or full/partial model-based IR [MBIR]) were compared. Acquisitions on Catphan 600 phantom were performed at 120kV and three dose levels (CTDIvol: 3, 7 and 12mGy). Raw data were reconstructed using standard "bone" kernel for filtered back projection and one iterative level of two generations of IR algorithms. Contrast-to-noise ratio (CNR) was computed using three regions of interest placed semi-automatically: two placed in the low-density polyethylene and Teflon inserts and another placed on the solid water. Noise power spectrum (NPS) was computed to assess the NPS-peak and noise-texture. RESULTS: CNR was significantly greater in MBIR compared to H/SIR algorithms for all CT systems (P<0.01). CNR were improved on average from H/SIR to MBIR of 36±14% [SD] (range: 24-57%) for GE-Healthcare, 109±19 [SD] % (range: 89-139%) for Philips Healthcare and 42±5 [SD] % (range: 36-47%) for Siemens Healthineers. The mean NPS peak decreased from H/SIR to MBIR by -41±6 [SD] % (range: -47--35%) for GE Healthcare, -79±3 [SD] % (range: -82--76%) for Philips Healthcare and -52±2 [SD] % (range: -54--51%) for Siemens Healthineers systems. NPS spatial frequencies were greater with MBIR than with H/SIR for Philips Healthcare (20 ± 2 [SD] %; range: 19-22%) and for Siemens Healthineers (9±5 [SD] %; range: 4-14%) but lower for GE Healthcare (-17±3 [SD] %; range: -14--20%). CONCLUSION: Using bone kernel with recent MBIR algorithms reduces the noise-magnitude for all CT systems assessed. Noise texture shifted towards high frequency for Siemens Healthineers and Philips Healthcare but the opposite for GE Healthcare.


Assuntos
Algoritmos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X , Humanos , Aumento da Imagem , Imagens de Fantasmas , Dosagem Radioterapêutica
4.
Diagn Interv Imaging ; 99(5): 321-329, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29396087

RESUMO

PURPOSE: To assess the value of the routine use of radiochromic films in abdominopelvic embolization procedures to improve patient follow-up. METHODS: A total of 55 patients who underwent transcatheter abdominopelvic embolization were prospectively included. Six types of procedures were evaluated including hepatic chemoembolization (HCE), gonadal veins embolization (GVE), uterine elective embolization (UEE), uterine urgent embolization (UUE), abdominal elective embolization (AEE), and abdominal urgent embolization (AUE). Dosimetric indicators (DIs) such as air-kerma (AK) and kerma-area-product (KAP) were collected and peak skin dose (PSD) was measured with radiochromic films. Correlations between PSD and DIs were searched for. RESULTS: The mean (±standard deviation [SD]) PSD for the various procedures were: 1033±502 mGy for HCE; 476±271 mGy for GVE; 460±171 mGy for UEE; 531±263 mGy for UUE; 708±896 mGy for AEE; 683±392 mGy for AUE. Strong correlations were observed between PSD and DIs (r=0.974 for AK and r=0.925 for KAP). PSD was>2Gy in one procedure and all procedures (7/132) procedures resulted in AK>2Gy, mostly for HCE and AEE. CONCLUSION: Dosimetry using radiochromic film is only appropriate for HCE, AEE and AUE, whereas dose-mapping systems present a more suitable solution for all embolizations including those with AK that occasionally exceed 2Gy.


Assuntos
Embolização Terapêutica/métodos , Doses de Radiação , Radiografia Intervencionista/métodos , Abdome , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pelve , Estudos Prospectivos , Radiometria/métodos , Pele/efeitos da radiação
5.
Eur J Clin Nutr ; 72(1): 69-76, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28853743

RESUMO

Evaluating and testing hydration status is increasingly requested by rehabilitation, sport, military and performance-related activities. Besides commonly used biochemical hydration assessment markers within blood and urine, which have their advantages and limitations in collection and evaluating hydration status, there are other potential markers present within saliva, sweat or tear. This literature review focuses on body fluids saliva, sweat and tear compared to blood and urine regarding practicality and hydration status influenced by fluid restriction and/or physical activity. The selected articles included healthy subjects, biochemical hydration assessment markers and a well-described (de)hydration procedure. The included studies (n=16) revealed that the setting and the method of collecting respectively accessing body fluids are particularly important aspects to choose the optimal hydration marker. To obtain a sample of saliva is one of the simplest ways to collect body fluids. During exercise and heat exposures, saliva composition might be an effective index but seems to be highly variable. The collection of sweat is a more extensive and time-consuming technique making it more difficult to evaluate dehydration and to make a statement about the hydration status at a particular time. The collection procedure of tear fluid is easy to access and causes very little discomfort to the subject. Tear osmolarity increases with dehydration in parallel to alterations in plasma osmolality and urine-specific gravity. But at the individual level, its sensitivity has to be further determined.


Assuntos
Desidratação/diagnóstico , Estado de Hidratação do Organismo , Saliva/química , Suor/química , Lágrimas/química , Atividades Cotidianas , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/urina , Pesquisa Comparativa da Efetividade , Desidratação/sangue , Desidratação/metabolismo , Desidratação/urina , Humanos , Concentração Osmolar , Reprodutibilidade dos Testes
6.
Phys Med ; 38: 16-22, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28610693

RESUMO

OBJECTIVE: To compare the use of a dose mapping software to Gafchromic film measurement for a simplified peak skin dose (PSD) estimation in interventional cardiology procedure. METHODS: The study was conducted on a total of 40 cardiac procedures (20 complex coronary angioplasty of chronic total occlusion (CTO) and 20 coronary angiography and coronary angioplasty (CA-PTCA)) conducted between January 2014 to December 2015. PSD measurement (PSDFilm) was obtained by placing XR-RV3 Gafchromic under the patient's back for each procedure. PSD (PSDem.dose) was computed with the software em.dose©. The calculation was performed on the dose metrics collected from the private dose report of each procedure. Two calculation methods (method A: fluoroscopic kerma equally spread on cine acquisition and B: fluoroscopic kerma is added to one air Kerma cine acquisition that contributes to the PSD) were used to calculate the fluoroscopic dose contribution as fluoroscopic data were not recorded in our interventional room. Statistical analyses were carried out to compare PSDFilm and PSDem.dose. RESULTS: The PSDFilm median (1st quartile; 3rd quartile) was 0.251(0.190;0.336)Gy for CA-PTCA and 1.453(0.767;2.011)Gy for CTO. For method-A, the PSDem.dose was 0.248(0.182;0.369)Gy for CA-PTCA and 1.601(0.892;2.178)Gy for CTO, and 0.267(0.223;0.446)Gy and 1.75 (0.912;2.584)Gy for method-B, respectively. For the two methods, the correlation between PSDFilm and PSDem.dose was strong. For all cardiology procedures investigated, the mean deviation between PSDFilm and PSDem.dose was 3.4±21.1% for method-A and 17.3%±23.9% for method-B. CONCLUSION: The dose mapping software is convenient to calculate peak skin dose in interventional cardiology.


Assuntos
Doses de Radiação , Pele/efeitos da radiação , Software , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia , Cardiologia/métodos , Angiografia Coronária , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Dosímetros de Radiação , Radiometria
7.
Radiat Prot Dosimetry ; 174(3): 395-405, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27522056

RESUMO

To assess the interest of Gafchromic films in detection of patient's peak skin dose (PSD) in interventional cardiology. A prospective study of 112 patients was conducted (July-December 2015). Three diagnostic and therapeutic procedures were evaluated: coronary angiography (CA), coronary angiography and coronary angioplasty for one or two vessels disease (CA-PTCA) and coronary angioplasty of complex chronic total occlusion (CTO). Dosimetric indicators (DIs) were collected and PSD were measured with Gafchromic films. Dose distribution was evaluated within 10 'Thorax Body-zone' defined by the system. Correlations between PSD and DI or dose distribution were computed. Delivered dose increased in complex procedures. The PSD were 0.121 ± 0.063 Gy for CA, 0.256 ± 0.142 Gy for CA-PTCA and 1.116 ± 0.721 Gy for CTO. High correlations were observed for PSD and DI as well for dose distribution within the 'Thorax Body-zone'. Film dosimetry is suggested for CTO procedures since the threshold of 2 Gy for skin injuries is likely to be exceeded.


Assuntos
Angiografia Coronária , Doses de Radiação , Cardiologia , Dosimetria Fotográfica , Humanos , Estudos Prospectivos , Radiografia Intervencionista , Pele
8.
Radiat Prot Dosimetry ; 174(2): 207-215, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-27150522

RESUMO

In this study, the impact of radiochromic films' (XR-RV3) calibration on PSD measurements was investigated under various peak kilovoltage (kVp) and additional filtration conditions. Films were calibrated free-in-air for six beam qualities with Allura Xper FD20 system (Philips). Six calibration curves (CCs) were constructed. Each beam quality was characterized in terms of mean energy (ME) in the air, with table, with table and water phantom using Monte Carlo simulations. A cohort of 155 patient films from cardiology (37) and vascular (118) procedures were read with each CC. Routine calibration beam quality was taken as reference (DoseNorm). Overall, it was observed that for a wider ME difference between the exposed film and the CC used, a larger deviation (from -28% to +41%) was observed. The choice of beam quality for the calibration is a key point when additional filtration and kVp are automatically controlled in clinical conditions.


Assuntos
Método de Monte Carlo , Radiologia Intervencionista , Calibragem , Dosimetria Fotográfica , Humanos , Imagens de Fantasmas
9.
Dermatology ; 225(1): 45-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22922888

RESUMO

Economic evaluation is an increasingly important aspect of assessment of the burden of skin diseases. Although dermatology data were not used in its development, the use of the EQ-5D questionnaire has been encouraged by the requirement of health technology assessment agencies for utility comparisons informing reimbursement decisions. The aim of this review was to examine the use of the EQ-5D in dermatology and to consider its future role in the economic evaluation of skin diseases. Published studies reporting the use of the EQ-5D in the economic analysis of skin diseases were carefully examined. Nineteen articles and 1 abstract published between 2003 and 2011 were identified, in which cost-of-illness, cost-effectiveness and cost-utility analyses were described. The EQ-5D is not a dermatology-specific measure, and it is not yet clear whether it is the most appropriate measure to support economic evaluation in the context of dermatology.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Índice de Gravidade de Doença , Dermatopatias/economia , Inquéritos e Questionários , Análise Custo-Benefício , Nível de Saúde , Humanos , Qualidade de Vida/psicologia , Anos de Vida Ajustados por Qualidade de Vida , Dermatopatias/terapia
10.
J Fr Ophtalmol ; 34(9): 629-33, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21889229

RESUMO

AIM: To assess the costs and cost-effectiveness ratio of topical and peribulbar anesthesia in non-penetrating deep sclerectomy for the surgical treatment of open-angle glaucoma. PATIENTS AND METHODS: We evaluated the associated direct costs with both topical and peribulbar anesthesia. Effectiveness was defined as the proportion of patients that experienced no pain during the surgical procedure and was obtained from the literature. Cost-effectiveness was defined as direct cost of anesthesia per patient with no pain. We also calculated the incremental cost-effectiveness ratio (ICER) in order to determine which intervention was dominant. RESULTS: Direct costs were US$ 45.60 and US$ 49.18 for topical and peribulbar anesthesia respectively. The great majority of patients experienced no pain with any of the procedures (91.7% for the topical group and 69.7% for the peribulbar group). Cost-effectiveness ratio was US$ 49.73 for topical anesthesia and US$ 70.56 for peribulbar anesthesia. The ICER was negative and topical anesthesia was dominant over peribulbar anesthesia. CONCLUSION: Topical anesthesia was less costly and more effective than peribulbar anesthesia in avoiding pain in non-penetrating deep sclerectomy.


Assuntos
Anestesia Local/economia , Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Procedimentos Cirúrgicos Oftalmológicos , Administração Tópica , Adulto , Idoso , Algoritmos , Anestésicos Locais/economia , Brasil , Análise Custo-Benefício , Custos e Análise de Custo , Glaucoma de Ângulo Aberto/cirurgia , Custos de Cuidados de Saúde , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Procedimentos Cirúrgicos Oftalmológicos/economia , Procedimentos Cirúrgicos Oftalmológicos/reabilitação , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Int J Sports Med ; 31(1): 10-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20029734

RESUMO

This study intended to investigate walking economy (WE) in response to different treadmill speeds and grades in adults with Down syndrome (DS) and in non-disabled controls. Eighteen participants (14 males; 4 females) with DS (33.6+/-7.6 years) and 16 non-disabled (12 males, 4 females) controls (33.3+/-8.0 years) performed submaximal (2.5 km . h (-1) and 4 km . h (-1) at 0% grade; 4 km . h (-1) at 2.5% and 5% grade, for 5 min each) and maximal treadmill tests with metabolic and heart rate measurements. Oxygen uptake (VO(2)) was not different between groups at rest or during the slowest treadmill speed. However, at faster speeds and increased grades, adults with DS presented lower WE than controls (p<0.0001). Subsequent analyses revealed that, despite showing higher delta VO(2) response to the selected speed increments (p<0.0001), individuals with DS produced similar VO(2) increase as controls to grade variations. Therefore, adults with DS exhibit lower WE than non-disabled controls at a speed faster than their preferred walking speed. Additionally, in comparison to controls, individuals with DS show a greater change in energy expenditure with a change in walking speed. In conclusion, lower WE in individuals with DS is mainly related to their inability to adapt efficiently to positive variations in walking speed.


Assuntos
Síndrome de Down/fisiopatologia , Consumo de Oxigênio/fisiologia , Caminhada/fisiologia , Adulto , Estudos de Casos e Controles , Síndrome de Down/metabolismo , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino
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