RESUMEN
OBJECTIVE: The objective of the study was to examine the association between occupational exposure to pesticides and cutaneous melanoma, controlling for all possible confounders. METHODS: A pooled analysis of two case-control studies was conducted in two different geographic areas (Italy and Brazil). Detailed pesticides exposure histories were obtained. RESULTS: Ever use of any pesticide was associated with a high risk of cutaneous melanoma (odds ratio 2.58; 95% confidence interval 1.18-5.65) in particular exposure to herbicides (glyphosate) and fungicides (mancozeb, maneb), after controlling for confounding factors. When subjects were exposed to both pesticides and occupational sun exposure, the risk increased even more (odds ratio 4.68; 95% confidence interval 1.29-17.0). CONCLUSIONS: The study suggests an augmented risk of cutaneous melanoma among subjects with exposure to pesticides, in particular among those exposed to occupational sun exposure.
Asunto(s)
Melanoma/epidemiología , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Plaguicidas/toxicidad , Neoplasias Cutáneas/epidemiología , Luz Solar/efectos adversos , Adulto , Anciano , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Fungicidas Industriales/toxicidad , Glicina/análogos & derivados , Glicina/toxicidad , Herbicidas/toxicidad , Humanos , Italia/epidemiología , Masculino , Maneb/toxicidad , Melanoma/etiología , Persona de Mediana Edad , Enfermedades Profesionales/etiología , Oportunidad Relativa , Factores de Riesgo , Neoplasias Cutáneas/etiología , Encuestas y Cuestionarios , Adulto Joven , Zineb/toxicidad , GlifosatoRESUMEN
This paper proposes a new design methodology for discrete multi-pumped Raman amplifier. In a multi-objective optimization scenario, in a first step the whole solution-space is inspected by a CW analytical formulation. Then, the most promising solutions are fully investigated by a rigorous numerical treatment and the Raman amplification performance is thus determined by the combination of analytical and numerical approaches. As an application of our methodology we designed an photonic crystal fiber Raman amplifier configuration which provides low ripple, high gain, clear eye opening and a low power penalty. The amplifier configuration also enables to fully compensate the dispersion introduced by a 70-km singlemode fiber in a 10 Gbit/s system. We have successfully obtained a configuration with 8.5 dB average gain over the C-band and 0.71 dB ripple with almost zero eye-penalty using only two pump lasers with relatively low pump power.
Asunto(s)
Amplificadores Electrónicos , Tecnología de Fibra Óptica/instrumentación , Rayos Láser , Espectrometría Raman/instrumentación , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Modelos Teóricos , Fotones , Dispersión de RadiaciónRESUMEN
In this paper we discuss the use of photonic crystal fibers (PCFs) as discrete devices for simultaneous wideband dispersion compensation and Raman amplification. The performance of the PCFs in terms of gain, ripple, optical signal-to-noise ratio (OSNR) and required fiber length for complete dispersion compensation is compared with conventional dispersion compensating fibers (DCFs). The main goal is to determine the minimum PCF loss beyond which its performance surpasses a state-of-the-art DCF and justifies practical use in telecommunication systems.
Asunto(s)
Amplificadores Electrónicos , Fibras Ópticas , Espectrometría Raman/instrumentación , Diseño Asistido por Computadora , Cristalización , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
ABSTRACT Meat is an excellent medium for the growth of microorganisms and it can be responsible for the transmission of pathogenic bacteria to human. The aim of this work was to analyze the sanitary-hygienic quality of ground beef and fresh sausages commercialized in southern Brazil and to evaluate the resistance profile of Salmonella isolates to antimicrobial agents. The methods used in the thermotolerant coliforms counting and in the Salmonella isolation were according to Instrução Normativa nº 62/2003 from Brazils Ministério da Agricultura, Pecuária e Abastecimento. The Salmonella isolates were tested in regard to susceptibility to ampicilin (10 mcg), norfloxacin (10 mcg), tetracycline (30 mcg), nalidixic acid (30 mcg) and chloramphenicol (30 mcg) antimicrobials. From 67 samples analized, 12 were not within the limits established by the current legislation to thermotolerant coliforms and Salmonella. Salmonella Typhimurium was isolated from 1 (4.2%) sample of ground beef. Salmonella serotypes Typhimurium and Infantis were isolated from 2 (9.5%) samples of pork meat sausages, and serotypes Typhimurium, Infantis, Derby from 3 (13.6%) samples of poultry sausages. The 6 (100%) isolates were sensitive to norfloxacina and ampicilina. Three (50%) isolates were sensitive to tetracycline, 3 (50%) to chloramphenicol and 2 (33.3%) to nalidixic acid. The results highlight the importance of meat products from swine, cattle and chicken as sources of Salmonella contamination.
RESUMO A carne constitui excelente meio para a multiplicação de microrganismos, podendo ser responsável pela transmissão de doenças para o homem através de bactérias patogênicas. O trabalho teve por objetivo analisar a qualidade higiênico-sanitária da carne bovina moída e de embutidos frescais comercializados no sul do Brasil e avaliar o perfil de resistência dos isolados de Salmonella a agentes antimicrobianos. Os métodos utilizados na contagem de coliformes termotolerantes e no isolamento de Salmonella foram realizados de acordo com a Instrução Normativa nº 62/2003 do Ministério da Agricultura, Pecuária e Abastecimento. Os isolados de Salmonella foram testados quanto à sensibilidade aos antimicrobianos ampicilina (10 mcg), norfloxacina (10 mcg), tetraciclina (30 mcg), ácido nalidíxico (30 mcg) e cloranfenicol (30 mcg). De 67 amostras analisadas, doze não atenderam aos limites estabelecidos pela legislação vigente para coliformes termotolerantes e Salmonella. Salmonella Typhimurium foi isolada de uma (4,2%) amostra de carne moída. Salmonella sorotipos Typhimurium e Infantis foram isoladas de duas (9,5%) amostras de lingüiça suína e sorotipos Typhimurium, Infantis e Derby de três (13,6%) amostras de lingüiça de frango. Os seis (100%) isolados foram sensíveis à norfloxacina e à ampicilina. Três (50%) isolados foram sensíveis à tetraciclina, três (50%) ao cloranfenicol e dois (33,3%) ao ácido nalidíxico. Os resultados obtidos ressaltam a importância dos produtos cárneos de origem suína, bovina e avícola como fonte de contaminação por Salmonella.