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71.
RL Cerqueira M Kawarabayashi AC Guimar?es PM Nakamura SN Ferraz PL Pinto HF de Andrade 《Canadian Metallurgical Quarterly》1998,59(5):736-740
The northeastern highlands of Brazil are endemic for several tropical diseases, especially American trypanosomiasis (Chagas' disease) and schistosomiasis. Twenty years ago, we measured the seroprevalence of protozoan diseases in Santo Inácio, a village of approximately 1,000 inhabitants located 1,000 m above sea level. We detected small numbers of sera with antibodies against Trypanosoma cruzi and Toxoplasma gondii, and the area had a low prevalence both of American trypanosomiasis (3.54%) and toxoplasmosis (27.43%) compared with nearby Brazilian areas. This was attributed to a specific triatomine vector and local housing conditions. Twenty years later, we again determined the prevalences of both diseases and compared these results with those from Iraquara, a larger town with the same ethnic and social background but with a higher prevalence of rural activities. The incidence of Chagas' disease in San Inácio showed the same low level, i.e., 3.78% (5 of 132) with only adult males affected in contrast with Iraquara, which had an incidence of 34.5%, but a low prevalence of only one of 22 among children up to 14 years of age. Santo Inácio maintained a low (25.8%) seroprevalence for toxoplasmosis. Housewives presented a higher incidence of toxoplasmosis during both periods, probably due to related risk factors. Cats were found less frequently in Santo Inácio than in Iraquara, which showed an incidence of 65.5% seropositivity for Toxoplasma gondii. These results suggest that the environmental conditions of Santo Inácio were preserved after 20 years, with a low incidence of these selected protozoan diseases. 相似文献
72.
Eduardo Rafael Barreda del Campo Srgio Augusto Araújo da Gama Cerqueira Silvia Azucena Nebra 《Energy Conversion and Management》1998,39(16-18)
Cogeneration is usual practice in sugar-cane mills. In this work, thermoeconomic analysis is applied to the cogeneration system of a typical Cuban sugar-cane mill. Two different cost attribution methods, the extraction method and the equality method are used to evaluate the exergetic and monetary (operational) costs of each flux within the system, especially the steam and generated power. The methodology indicates the equipment responsible for the greatest irreversibility and for the increase in the costs of the products of the system. 相似文献
73.
Recurrent unipolar depression with an early age of onset is a severe form of unipolar depression that has both genetic and environmental components. We genotyped the members of 16 families identified by probands with early onset (< or = 25 years), recurrent unipolar, major depression for 38 simple sequence tandem repeat polymorphisms (SSTRPs) from chromosomal regions containing 12 genes involved in neuroendocrine or serotonergic functioning. Pairwise linkage analysis was performed with the software package FASTLINK. The affected phenotype was defined four ways, and both dominant and recessive models of depression were analyzed. Seven SSTRPs showed lod scores > 1.00 at theta values between 0.10-0.20. The members of an additional 18 families were genotyped for these seven SSTRPs, and the complete sample of 34 families was evaluated using lod score analysis, affected pedigree member linkage analysis, and within-family association analysis. Evidence for linkage between D11S929 and affective illness remained positive, necessitating the analysis of four additional SSTRPs within 3 cM of D11S929. After all confirmatory analyses were completed, no evidence suggestive of linkage remained between any of the 38 SSTRPs and the affected phenotypes. 相似文献
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75.
Mesquita JR Vaz L Cerqueira S Castilho F Santos R Monteiro S Manso CF Romalde JL Nascimento MS 《Food microbiology》2011,28(5):936-941
This is the first report on the screening of shellfish from Portugal for the presence of human enteropathogenic viruses. Approximately 2000 shellfish (Curbicula fluminea, Ruditapes decussatus, Tellina crassa, Spisula solida, Dosinia exoleta, Ensis spp., Mytilus spp., Ostrea edulis and Cerastoderma edule), organized in 49 batches, were collected between March 2008 and February 2009. They were tested for norovirus (NoV), hepatitis A virus (HAV) and enterovirus (EV) by RT-PCR followed by nucleotide sequencing. Bacterial contamination was also evaluated by Escherichia coli counts. Viral contamination was detected throughout the year in all shellfish species and in all collection areas, independently of their harvesting areas classification. Overall, 67% of all analyzed batches were contaminated by at least one of the studied viruses while the simultaneous presence of two and three viruses was detected in 22% and 6% batches, respectively. Of the three viruses, NoV was detected in 37% of the batches, followed by EV in 35%, and HAV in 33%. Nucleotide sequencing of the NoV and HAV RT-PCR products demonstrated that all strains belonged to NoV genotype GII.4 and HAV subgenotype 1B. The presence of NoV and HAV in shellfish from “A class” harvesting areas of Portugal can represent a potential health risk. 相似文献
76.
Geraldo Mauricio Cândido Mirabel Cerqueira Rezende Sérgio Frascino M. de Almeida 《Polymer-Plastics Technology and Engineering》2013,52(10):1109-1115
Moisture and high temperature may cause a variety of effects on the mechanical and thermophysical properties of polymeric composites. The diffusion of moisture in the laminate occurs primarily by capillarity until a state of equilibrium is reached. Moisture affects the matrix and the fiber/matrix interface. The stacking sequence and the free edge finishing may affect the laminate tensile strength causing a free edge delamination; they can also affect the moisture absorption process. Laminates produced with molded edges do not require machining operations for the trimming and finishing of the free edges causing a gain in productivity. However, the mechanical behavior of laminates with molded edges saturated with moisture has not been characterized. This work presents a comparative study of the tensile strength of cross ply laminates with molded and machined edges under dry condition and saturated with moisture. 相似文献
77.
Bartolomeu G. de S. Medeiros Marthyna P. Souza Ana C. Pinheiro Ana I. Bourbon Miguel A. Cerqueira António A. Vicente Maria G. Carneiro-da-Cunha 《Food and Bioprocess Technology》2014,7(4):1088-1098
This work aimed at the characterisation of a nano-laminate coating produced by the layer-by-layer methodology and its evaluation on the preservation of ‘Coalho’ cheese. Initially, five alternate layers of alginate and lysozyme were assembled in an aminolysed/charged polyethylene terephthalate (A/C PET) and physically characterised by UV/VIS spectroscopy, contact angle, water vapour (WVTR) and oxygen (OTR) transmission rates and scanning electron microscopy. Afterwards, the same methodology was used to apply the nano-laminate coating in ‘Coalho’ cheese and its shelf life was evaluated during 20 days in terms of mass loss, pH, lipid peroxidation, titratable acidity and microbial count. UV/VIS spectroscopy and contact angle analyses confirmed the layers’ deposition and the successful assembly of nano-laminate coating on A/C PET surface. The coating presented WVTR and OTR values of 1.03?×?10?3 and 1.28?×?10?4 g m?2 s?1, respectively. After 20 days, coated cheese showed lower values of mass loss, pH, lipidic peroxidation, microorganisms’ proliferation and higher titratable acidity in comparison with uncoated cheese. These results suggest that gas barrier and antibacterial properties of alginate/lysozyme nanocoating can be used to extend the shelf life of ‘Coalho’ cheese. 相似文献
78.
79.
Wireless Networks - The adoption of video-equipped vehicles in Vehicular ad-hoc networks (VANETs) is experiencing a rapid growth. It is also anticipated a substantial increase in the video content... 相似文献
80.
Alexandre Zacarias Ignácio Pereira Marcia Cerqueira Delpech Francileide Gomes da Costa Flávio Bittencourt da Cruz Pedro Rocha Tavares 《应用聚合物科学杂志》2019,136(16):47362
Two hydrolyzable polymers, poly(methylene oxide) (PMO) and poly(glycolic acid) (PGA), were tested for association with mechanical systems to promote diversion of formation acid treatments in oil wells. Samples were confined to chemical products commonly employed in oil well completion processes, HCl 15% w/w and NaCl 23% w/w aqueous solutions, in separate metallic cylindrical cells, under conditions observed in southeastern Brazilian offshore fields (50 and 75°C and pressure of 41.4 MPa). Pristine samples were characterized by 13C-NMR. Hydrolytic influences were evaluated by differential scanning calorimetry, scanning electron microscopy, wide angle X-ray diffraction, and computerized microtomography. The intense effects observed showed a specific correspondence with each tested polymer and were evidenced by postexposure analysis. The results indicate that both polymers can be used in association with mechanical diverting systems to promote chemical treatment distribution and, therefore, improve oil well productivity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47362. 相似文献