635 research outputs found

    Study of complexes of Poly(9-vinylcarbazole) with copper, cobalt and chromium on solid state

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    In this paper we have studied the synthesis and characterization in solution and on solid state of different poly(9-vinylcarbazole) with some transition metal chlorides suchas CuCl2・2H2O, CoCl2・6H2O and CrCl3・6H2O. The polymermetal complexes were characterized by FTIR and the result revealed that the infrared spectra of the complexes show significant shift with respect to that of PNVC, indicating that linking between the polymer and metal may be tacking place only through the tertiary nitrogen of the carbazole side group. The thermal stability and glass transition temperature of the polymer-metal complexes were found to be higher than that of the polymer. The pores of the polymer are filled after interaction with cation with polymeric ligand

    Evolution of Surface Roughness in Grinding and its Relationship with the Dressing Parameters and the Radial Wear

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    Grinding is a machining process specially indicated for finishing operations in hard materials, in order to obtain low surface roughness (Ra 0.1 μm to 2μm) and tight tolerances. The cutting tool is the grinding wheel which is formed by abrasive particles attached in a bond. The wear of these abrasive particles modifies significantly the roughness obtained in the workpiece. In this work, the evolution of part roughness has been continuously monitored as the grinding process progresses and the wheel gets worn. The roughness evolution is then related to different process variables such as the dressing parameters, the grinding conditions, the grinding forces and the radial wear of the wheel

    Prevalence of anemia and iron deficiency in pregnant women living in Cartagena, Colombia

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    According to the World Health Organization, anemia affects more than 40% of pregnant women worldwide. Iron-deficiency anemia is the most common type of anemia, and has been shown to have a direct impact on health and quality of life of both mother and child.Ferritin, and iron binding protein, can be used to assess the body’s stored iron and support diagnosis. This study assessed the prevalence of anemia and iron deficiency amongst pregnant women in the ESE Clinica Maternidad Rafael Calvo, a reference maternity unit in the department of Bolivar, Colombia

    Fall Protection Training: A Case Study Using Cbt for Latino Construction Workers

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    Latino construction workers are at an increased risk of worksite injuries and fatalities due to language, cultural barriers, and ineffective training. This case-study investigated computer-based video training (CBT) for scaffold safety. The CBT training was developed using a participatory approach involving direct input from Latino roofers and framers. This paper focuses on evaluation-improvement of training that combined workers’ ideas of a safe work environment with OSHA standards. Researchers investigated the appropriateness and effectiveness of a brief CBT presentation addressing fall protection and scaffold use among Latino roofers. The results indicated that Latino construction workers at a roofing company in Colorado gained knowledge (p-value \u3c0.05) and liked the use of a culturally appropriate educational video as a method of training. The positive reactions to the training intervention are encouraging and support information and communication technologies (ICTs) for training Latino construction workers with lessons learned for follow-up training and evaluation

    Inverse relationship between anemia in the third trimester of pregnancy and low birth weight in a reference maternity unit of a carribean region of Colombia

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    Anemia is common amongst women in developing countries. Although a relationship has been established between gestational anemia and negative perinatal outcomes, it remains a controversial debate as opposite associations have been found. This study assessed the relationship between gestational anemia in the third trimester and low birth weight (LBW) in the ESE Clinica Maternidad Rafael Calvo, a reference maternity unit in the department of Bolivar, Colombia

    Notes on the hematology of free-living Phrynops geoffroanus (Testudines: Chelidae) in polluted rivers of Southeastern Brazil

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    Phrynops geoffroanus (Schweigger, 1812) is the freshwater turtle with the widest geographical distribution in South America. During 2006, physical examination and hematological evaluation were performed on free-ranging turtles from two polluted rivers, the Piracicaba River (n = 51) and its tributary Piracicamirim (n = 42), in southeastern Brazil. Red blood cell and thrombocyte counts, mean corpuscular volume and mean corpuscular hemoglobin levels differed in turtles from the two water courses. Although free-ranging turtles showed ectoparasites and boat propeler lesions, animals apparently had no signs of clinical disease. In spite of our results, further monitoring of the demography and health status of Phrynops geoffroanus in anthropogenically altered environments is recommended.FAPESP [05/00210-9]CNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES
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