180 research outputs found

    Procedura di verifica del rispetto dei livelli di riferimento dell\u27induzione magnetica in presenza di forme d\u27onda complesse con frequenze fino a 100 kHz. PARTE I: ASPETTI GENERALI

    Get PDF
    .Le Linee Guida ICNIRP del 1998 (1) e lo Statement ICNIRP del 2003 (2) propongono nel complesso quattro approcci distinti per la verifica del rispetto dei livelli di riferimento ICNIRP in presenza di forme d\u27onda "complesse" a bassa frequenza, intendendosi con questo termine le forme d\u27onda pulsate o, in generale, non sinusoidali, aventi componenti spettrali di frequenza fino a 100 kHz. Tutti questi approcci conducono a definire un indice che rappresenta l\u27intensit? dell\u27esposizione ed a proporre un metodo per calcolarne il valore. I livelli di riferimento ICNIRP sono rispettati se tale valore risulta minore o uguale ad 1. In ogni caso gli indici sono calcolati separatamente per ogni componente cartesiana X,Y,Z del campo; l\u27indice complessivo ? dato dalla somma vettoriale degli indici delle tre componenti. In questo documento descriveremo questi metodi con riferimento alle esposizioni al campo magnetico in ambito occupazionale, ma quanto esporremo pu? essere sia facilmente esteso alle esposizioni della popolazione sia adattato al caso del campo elettrico

    DOMANDE E RISPOSTE SUL SISTEMA INTEGRATO DI VALUTAZIONE PREVENTIVA DELL'INQUINAMENTO ELETTROMAGNETICO AMBIENTALE A BASSISSIMA FREQUENZA PLEIA-CERT

    Get PDF
    L’ARPAT e l’IFAC-CNR collaborano ormai da oltre cinque anni allo sviluppo del Catasto degli Elettrodotti della Regione Toscana (CERT) e di un sistema integrato di applicazioni, denominato PLEIA (Power Line Electromagnetic Impact Assessment), per il suo utilizzo ai fini del calcolo del campo magnetico nello spazio circostante gli elettrodotti e, in particolare, della determinazione delle fasce di rispetto. Per rendere possibile a queste istituzioni un utilizzo corretto e consapevole degli strumenti realizzati e dei risultati da essi forniti, è stato indispensabile documentare innanzitutto i presupposti tecnici e metodologici che stanno alla base delle applicazioni sviluppate: a questo scopo, è venuto spontaneamente a crearsi un gruppo di lavoro informale tra esperti dell’ARPAT, dell’IFAC e della Regione Toscana. Il gruppo ha lavorato secondo un meccanismo virtuoso in cui, da un lato, si è cercato di formulare quesiti puntuali e ben definiti e, dall'altro, di rispondervi nel modo più chiaro ed esauriente possibile. Ne è scaturito un documento a domande e risposte che, opportunamente modificato, è riproposto in questa sede, perché mette in evidenza in modo semplice ma non banale alcuni rilevanti aspetti tecnici, e costituisce un buon documento introduttivo sulle potenzialità del sistema sviluppato. Le prime domande riguardano il sistema PLEIA-CERT in generale, mentre nella seconda parte si approfondiscono in particolare le modalità di calcolo delle fasce di rispetto che, anche alla luce di recenti sviluppi normativi, hanno assunto un ruolo di primaria importanza

    Ergonomics and Workflow Evaluation of Automatic Doppler Angle Technology Implemented in a Diagnostic Ultrasound System

    Get PDF
    AbstractCommonly available Pulsed Wave Doppler (PW) flow velocity measurements for Ultrasound (US) investigation require the operator to manually set the direction of the flow velocity vector along the blood vessel axis on the US image, in order to determine the Doppler angle and then to estimate the real flow velocity. The present work investigates the possibility to implement on a commercially available US system an innovative Automatic Doppler Angle (ADA) Technology by analyzing the best workflow in terms of higher execution speed, lower keystrokes/adjustments helping in the prevention of Work-related Musculoskeletal Disorders (WRMSD) and a Doppler angle correction precision, comparable to the one obtained manually by expert sonographer. Ergonomics and workflow tests, then accuracy and repeatability evaluations of the Doppler velocity measurement, were performed on a portable US system (MyLabAlpha, Esaote S.p.A., Florence, Italy) by an expert sonographer. Ergonomics and workflow Tests were performed to analyze the potential of ADA in terms of reduction of muscular activation applied (by SEMG), number of activations (by cameras optoelectronic system) and time needed using ADA, in comparison to manual procedure. Accuracy and intra-operator repeatability tests of the velocity measurement were performed to evaluate the precision of the obtained PW trace velocity measurements with ADA technology, compared to manual ones. Results provided evidence that ADA tool allowed: a reduction of muscular activation (from 12% for trapezius descendens, to 25% for deltoideus anterior) a lower total number of keystrokes and a reduction of the US scan time of about 56%. The maximal variation between PW Doppler trace velocity measurement set automatically by ADA and set manually by sonographer was 11%. ADA technology can provide a Doppler angle correction precision comparable to the manual one, while decreasing the risk of WRMSD

    Classification and standardization of tomatoes cv. Carmem and Debora in the CEAGESP - São Paulo - Brazil

    Get PDF
    The creation of the Brazilian Program for the Modernization of the Horticulture by the Secretariat of Agriculture and Supplying of the State of São Paulo at CEAGESP, determined the standardization of fruit and vegetables in the follow aspects: degree of coloration, format, calibers, defects and packing. Therefore, the main goal of this research is to correlate the classification given by the Brazilian Program with the one used by the wholesalers at CEAGESP, verifying if the established norms are being fulfilled for cultivar Carmen and Debora (SAKATA SEED). The results showed, that for cultivar Carmem, for the averages of the observed values it does not move away from the norms created by the Program for sizes small and medium. However, for the case of cultivar Debora, the results showed differences between the adopted classifications. The tomatoes were devaluated, because had been commercialized below of the standardization indicated for the Brazilian Program.A criação do Programa Brasileiro para a Modernização da Horticultura pela Secretaria de Agricultura e Abastecimento do Estado de São Paulo, em conjunto com a Companhia de Entrepostos e Armazéns Gerais de São Paulo (CEAGESP), determinou a padronização das hortaliças e frutas comercializadas nos seguintes aspectos: grau de coloração, formato, calibres, defeitos e embalagens, um trabalho iniciado em setembro de 1997. O objetivo deste trabalho foi relacionar a classificação fornecida pelo Programa Brasileiro com a realizada pelos atacadistas no mercado da CEAGESP, verificando se as normas estabelecidas estão sendo cumpridas para os tomates cultivares Carmem e Débora (SAKATA SEED). Os resultados mostraram que, para o tomate cultivar Carmem, a partir da análise de teste de hipótese de proporção, as médias dos valores observados não se afastam muito das normas criadas pelo Programa para os tamanhos pequeno e médio. Porém, para o caso do tomate cultivar Débora, encontraram-se, a partir dos resultados, diferenças entre as classificações adotadas, percebendo que os tomates estavam desvalorizados, pois estavam sendo comercializados em padronização inferior às normas indicadas pelo Programa Brasileiro.790798Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Real time determination of physical impact damage in packing lines and under laboratory conditions and its effects in tomato fruits quality

    Get PDF
    Tomatoes are one of the most important vegetable crops grown in Brazil and are among the crops that have one of the highest post-harvest losses indexes in the country. The present work aimed at evaluating impact damage observed in packing lines of fresh tomatoes as well as to determine, under laboratory conditions, quality alterations of tomato fruits submitted to impact damage in different surface types. Critical points evaluation was accomplished using an instrumented sphere. Critical transference points found showed variations in acceleration levels from 30 to 129 G (m s-2). Tests carried out under laboratory conditions showed that padded surfaces reduced up to 31% impact damage. Incidence of severe internal physical damage was evaluated by a subjective scale and increased by 79% on hard surfaces for the highest fall drop. On the other hand, it was observed an effective reduction in physical damage on fruits when padded surfaces were used. When a 10-cm drop was performed, the maximum reduction measured was 10% for hard surfaces and 5% for previously padded surfaces. For quality parameters, it was observed for high drops on hard surfaces, highest values for weight loss, total acidity, lower values for vitamin C and Soluble Solids.O tomate de mesa é uma das principais hortaliças consumidas no Brasil e apresenta elevados índices de perdas pós-colheita. O objetivo deste trabalho foi avaliar a magnitude dos impactos verificados em linhas de beneficiamento para tomate de mesa, bem como determinar, em laboratório, as alterações na qualidade de tomates submetidos a danos físicos controlados em diferentes superfícies. Para a avaliação dos pontos críticos e registro da magnitude dos impactos, foi usada uma esfera instrumentada. Os pontos críticos de transferência demonstraram valores de aceleração entre 30 e 129 G (m s-2). Os testes laboratoriais evidenciaram que superfícies acolchoadas reduziram em até 31% a magnitude de impacto. A incidência de danos físicos internos foi crescente e atingiu 79% em superfícies rígidas para a maior altura de queda livre. Por outro lado, observou-se redução na incidência de danos físicos nos frutos quando superfícies protetoras foram utilizadas, verificando-se na altura de 10 cm um limite mínimo de 5% de danos severos, enquanto para superfície rígida o mínimo correspondeu a 10%. As variáveis de qualidade foram alteradas, verificando-se maior perda de massa, maiores valores de acidez total, menores valores de ácido ascórbico e sólidos solúveis para maiores alturas de queda livre sobre superfícies rígidas.630641Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Extremely low-frequency electromagnetic fields do not affect DNA damage and gene expression profiles of yeast and human lymphocytes

    Get PDF
    We studied the effects of extremely low-frequency (50 Hz) electromagnetic fields (EMFs) on peripheral human blood lymphocytes and DBY747 Saccharomyces cerevisiae. Graded exposure to 50 Hz magnetic flux density was obtained with a Helmholtz coil system set at 1, 10 or 100 microT for 18 h. The effects of EMFs on DNA damage were studied with the single-cell gel electrophoresis assay (comet assay) in lymphocytes. Gene expression profiles of EMF-exposed human and yeast cells were evaluated with DNA microarrays containing 13,971 and 6,212 oligonucleotides, respectively. After exposure to the EMF, we did not observe an increase in the amount of strand breaks or oxidated DNA bases relative to controls or a variation in gene expression profiles. The results suggest that extremely low-frequency EMFs do not induce DNA damage or affect gene expression in these two different eukaryotic cell systems

    Impact of neoadjuvant therapy followed by laparoscopic radical gastrectomy with D2 lymph node dissection in Western population: A multi-institutional propensity score-matched study

    Get PDF
    Background and Objectives: In the setting of a minimally invasive approach, we aimed to compare short and long-term postoperative outcomes of patients treated with neoadjuvant therapy (NAT) + surgery or upfront surgery in Western population. Methods: All consecutive patients from six Italian and one Serbian center with locally advanced gastric cancer who had undergone laparoscopic gastrectomy with D2 lymph node dissection were selected between 2005 and 2019. After propensity score-matching, postoperative morbidity and oncologic outcomes were investigated. Results: After matching, 97 patients were allocated in each cohort with a mean age of 69.4 and 70.5 years. The two groups showed no difference in operative details except for a higher conversion rate in the NAT group (p = 0.038). The overall postoperative complications rate significantly differed between NAT + surgery (38.1%) and US (21.6%) group (p = 0.019). NAT was found to be related to a higher risk of postoperative morbidity in patients older than 60 years old (p = 0.013) but not in patients younger (p = 0.620). Conversely, no difference in overall survival (p = 0.41) and disease-free-survival (p = 0.34) was found between groups. Conclusions: NAT appears to be related to a higher postoperative complication rate and equivalent oncological outcomes when compared with surgery alone. However, poor short-term outcomes are more evident in patients over 60 years old receiving NAT
    • …
    corecore