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1.
Rev Gastroenterol Mex (Engl Ed) ; 87(3): 297-304, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34794928

RESUMO

INTRODUCTION AND AIMS: Colonoscopy quality is measured by the degree in which the examination increases the likelihood of obtaining adequate results on health. Our aim was to develop an instrument for evaluating the quality of screening colonoscopies, taking into account the performance of endoscopists and endoscopy units. MATERIALS AND METHODS: Mixed methodology was employed. The first stage (qualitative) consisted of a Medline search, from which a group of experts developed the quality score items. The second stage (quantitative) utilized a modified Delphi technique to reach consensus (3 rounds). We evaluated the psychometric properties of the instrument (reliability and construct validity) in elective screening colonoscopies (in patients ≥ 50 years of age), performed within the January-April 2017 time frame. RESULTS: A final instrument with 8 items was produced: (1) the Boston Bowel Preparation Scale score; (2) cecal intubation rate; (3) colonoscopy withdrawal time; (4) image documentation; (5) adenoma detection rate; (6) endoscopic surveillance planning; (7) perforation rate, and (8) continuous improvement programs. The instrument was evaluated in 323 colonoscopies performed by 31 endoscopists and found to be one-dimensional and reliable (Cronbach's alpha 0.76). Performance was compared between endoscopists (center 1) and an expert endoscopist from another center (center 2): Boston Bowel Preparation Scale score 8.3 vs. 7.36 (P < .001), cecal intubation rate 93.5 vs. 96%, colonoscopy withdrawal time 14.8 vs. 8.4 min (P < .001), and adenoma detection rate 34 vs. 52.2% (P < .001), respectively. CONCLUSION: The Colonoscopy Quality Score is a reliable and valid instrument for evaluating screening colonoscopy quality. Its results could be adapted to the usual endoscopic report to adjust monitorization frequency post-colonoscopy.


Assuntos
Adenoma , Neoplasias Colorretais , Adenoma/diagnóstico , Ceco , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Humanos , Psicometria , Reprodutibilidade dos Testes
2.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34312017

RESUMO

INTRODUCTION AND AIMS: Colonoscopy quality is measured by the degree in which the examination increases the likelihood of obtaining adequate results on health. Our aim was to develop an instrument for evaluating the quality of screening colonoscopies, taking into account the performance of endoscopists and endoscopy units. MATERIALS AND METHODS: Mixed methodology was employed. The first stage (qualitative) consisted of a Medline search, from which a group of experts developed the quality score items. The second stage (quantitative) utilized a modified Delphi technique to reach consensus (3 rounds). We evaluated the psychometric properties of the instrument (reliability and construct validity) in elective screening colonoscopies (in patients≥50 years of age), performed within the January-April 2017 time frame. RESULTS: A final instrument with 8 items was produced: 1) the Boston Bowel Preparation Scale score; 2) cecal intubation rate; 3) colonoscopy withdrawal time; 4) image documentation; 5) adenoma detection rate; 6) endoscopic surveillance planning; 7) perforation rate, and 8) continuous improvement programs. The instrument was evaluated in 323 colonoscopies performed by 31 endoscopists and found to be one-dimensional and reliable (Cronbach's alpha 0.76). Performance was compared between endoscopists (center 1) and an expert endoscopist from another center (center 2): Boston Bowel Preparation Scale score 8.3 vs. 7.36 (P<.001), cecal intubation rate 93.5 vs. 96%, colonoscopy withdrawal time 14.8 vs. 8.4min (P<.001), and adenoma detection rate 34 vs. 52.2% (P<.001), respectively. CONCLUSION: The Colonoscopy Quality Score is a reliable and valid instrument for evaluating screening colonoscopy quality. Its results could be adapted to the usual endoscopic report to adjust monitorization frequency post-colonoscopy.

3.
Waste Manag ; 51: 182-189, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26777778

RESUMO

The aim of the study is the recovery by thermal treatment of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, on the basis of the different phase change temperatures of the two metal-bearing phases. ASR (Automotive Shredder Residue), containing 68% of carbon, was added to the mixture to act as a reductant to metallic Zn of the zinc-bearing phases. The mixture was subsequently heated in different atmospheres (air, CO2 and N2) and at different temperatures (900°C, 1000°C and 1200°C) and stoichiometric excess of ASR (300%, 600% and 900%). Characterization of the mixture and of the residues of thermal treatment was carried out by chemical analysis, TGA/DTA, SEM and XRD. The results show that recovery of 99% of zinc (grade 97%) is achieved at 1000°C in N2 with a stoichiometric excess of car-fluff of 900%. This product could be suitable for production of new batteries after refining by hydrometallurgical way. Recovery of Mn around 98% in the residue of the treatment is achieved at any temperature and atmosphere tested with a grade of 57% at 900% excess of car-fluff. This residue is enriched in manganese oxide and could be used in the production of iron-manganese alloys.


Assuntos
Fontes de Energia Elétrica , Resíduos Industriais/análise , Manganês/análise , Reciclagem/métodos , Gerenciamento de Resíduos/métodos , Zinco/análise , Automóveis , Carbono , Ferro/análise , Compostos de Manganês/análise , Óxidos/análise , Temperatura
4.
Waste Manag ; 32(10): 1945-51, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22677015

RESUMO

The aim of this paper is the recovery of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, containing 40.9% of Mn and 30.1% of Zn, after preliminary physical treatment followed by removal of mercury. Separation of the metals has been carried out on the basis of their different boiling points, being 357°C and 906°C the boiling point of mercury and zinc and 1564°C the melting point of Mn(2)O(3). Characterization by chemical analysis, TGA/DTA and X-ray powder diffraction of the mixture has been carried out after comminution sieving and shaking table treatment to remove the anodic collectors and most of chlorides contained in the mixture. The mixture has been roasted at various temperatures and resident times in a flow of air to set the best conditions to remove mercury that were 400°C and 10 min. After that, the flow of air has been turned into a nitrogen one (inert atmosphere) and the temperatures raised, thus permitting the zinc oxide to be reduced to metallic zinc by the carbon present in the original mixture and recovered after volatilization as a high grade concentrate, while manganese was left in the residue. The recovery and the grade of the two metals, at 1000°C and 30 min residence time, were 84% and 100% for zinc and 85% and 63% for manganese, respectively. The recovery of zinc increased to 99% with a grade of 97% at 1200°C and 30 min residence time, while the recovery and grade of manganese were 86% and 87%, respectively, at that temperature. Moreover, the chlorinated compounds that could form by the combustion of the plastics contained in the spent batteries, are destroyed at the temperature required by the process.


Assuntos
Manganês/isolamento & purificação , Reciclagem , Zinco/isolamento & purificação , Temperatura Alta , Mercúrio/isolamento & purificação , Termogravimetria , Difração de Raios X
5.
Waste Manag ; 27(2): 238-47, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16527475

RESUMO

A step-wise treatment of Municipal Solid Waste (MSW) incinerator fly ash including washing, milling and sintering was investigated in order to manufacture ceramic materials with improved physical, mechanical and environmental properties and, possibly, to reduce the power input of the sintering process. An interpretation of the test results based on the microstructure of sintered products and sintering kinetic modeling was also attempted to identify the densification mechanisms. It was found that milling of washed fly ash represents a basic step for manufacturing high-density ceramic materials with very high compressive strengths (up to 500 N/mm2). A significant reduction in the power input of the sintering process (reduction of firing temperature from 1210 degrees C for washed fly ash to 1140 degrees C for milled-washed fly ash) is also achieved. A dense, well-sintered microstructure is formed through an intermediate-stage, liquid-phase sintering mechanism controlled by liquid-phase diffusion and grain shape accommodation. Such a microstructure is able to strongly immobilise heavy metals, thus giving good environmental properties to sintered product.


Assuntos
Carbono/química , Cidades , Incineração , Material Particulado/química , Cinza de Carvão , Tamanho da Partícula , Temperatura , Gerenciamento de Resíduos
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