BACKGROUND Deforestation, driven by anthropogenic change in land use, influences the behaviour and abundance of vector-borne diseases. For various species of Chagas disease vectors, there is evidence that change in land use affects population density and abundance. Triatoma dimidiata is the most important Chagas vector in Guatemala, and at least one million people live in T. dimidiata endemic areas; however, infestation dynamics vary among regions, from high infestation with all life stages to low seasonal infestation by sylvatic adults. OBJECTIVES The aim of this study was to evaluate how land-use, combined with domiciliary risk factors, influences the infestation dynamics of T. dimidiata for four villages in a dry forest region with a strong deforestation history. METHODS Land use, measured with drone and satellite images, was classified into four categories (houses, monocultures and pastures, woodland and shrubland, and bare soil). Domiciliary risk factors and infestation were assessed through entomological surveys. Statistical analyses compared infestation indices and the ability of land use and domiciliary risk factors to explain infestation. FINDINGS Two villages had significantly higher infestation (26 and 30% vs. 5 and 6%), yet all villages had high colonisation (71-100% of infested houses had immature insects), with no significant difference among them. Because of the high level of deforestation across the study area, land use was not related to infestation; however, domiciliary risk factors were. A model based on four weighted domiciliary risk factors (adobe or bajareque walls, intradomicile animals, intradomicile clutter, and dirt floors) explains the infestation risk. MAIN CONCLUSIONS Because almost all infested houses have reproducing populations in this deforested dry forest region and statistical analysis identified the domiciliary risk factors for infestation, intermediate and long-term control of Chagas disease vectors in this region requires management of these risk factors.

The chemical modification of cellulose by grafting reaction with Acrylic Acid (AA) considering different reaction factors was investigated. Natural polymers such as Santa Fe Cellulose, Microcrystalline Cellulose (Avicell) and Secondary Pulp were studied as substrates. pH effect; Ce (IV), Mn(VII) and Fenton as initiators; time and temperature polymerization were investigated. Grafting reachs a maximum, 90 % graft, at pH 7. A medium to weak C=0 band at 1715 cm"¹ for carboxylic group in FTIR spectroscopy is presented. Santa Fe and Avicel cellulose grafted whith AA at 17 hours are degraded. Secondary pulp with Fenton at 50-60 and 70 °C at 17 hours are degraded too. The degradation of polymers at long reaction times at 17 hours and 70°C were analized by FTIR spectroscopy and electronic microscopy analysis (SEM).

JUSTIFICATIVA E OBJETIVOS: A endocardite é rara e grave complicação de brucelose humana. O diagnóstico é suspeito em casos de endocardite sem resposta ao tratamento comum e é confirmado com sorologia com teste de ELISA maior que 1:160. O tratamento na maioria dos casos é cirúrgico, associado a antibioticoterapia prolongada. Alguns casos são resolvidos com tratamento clínico, que inclui doxiciclina, rifampicina, ciproproxacina, gentamicina e tetraciclina. O objetivo deste estudo foi relatar um caso raro de endocardite por brucelose. RELATO DO CASO: Paciente do sexo masculino, 51 anos, trabalhador rural, admitido com quadro de febre e emagrecimento. O ecocardiograma mostrou espessamento e vegetação de válvula aórtica. Uma hemocultura foi positiva para Staphylococcus epidermidis. O tratamento foi iniciado no dia da internação com penicilina cristalina, associada com garamicina, sem melhora em três semanas. Foi suspeitada endocardite por brucelose, colhida sorologia e iniciado o tratamento. Os antibióticos usados foram rifampicina e ciprofloxacin associado à vancomicina, devido o resultado da primeira hemocultura. A sorologia de aglutinação para brucelose foi positiva com resultado de 1:360. O paciente melhorou e recebeu alta da UTI, hemodinamicamente estável e em uso de ciprofloxacin e gentamicina. CONCLUSÕES: A endocardite por brucelose não é comum, mas deve ser sempre lembrada quando o tratamento convencional de endocardite não tem boa resposta, principalmente nos pacientes com possível contato com animais e derivados de leite.

BACKGROUND AND OBJECTIVES: Endocarditis is a rare and serious complication of human brucellosis. The diagnosis is suspected in cases of endocarditis without response to conservative antibiotic treatment and it is confirmed with enzyme-linked immunosorbent assay (ELISA) test, titers being higher than 1:160. The treatment is usually a surgery, followed with antibiotics for long period of time. Some cases can be cured with antibiotic treatment only, with antibiotics such as doxiciclin, rifampicin, ciprofloxacin, gentamicin and tetracycline. We present a case report of a patient with brucellose endocarditis. CASE REPORT: Fifty one year old male patient, a farmer, was admitted with clinical history of fever and weight loss. Echocardiography showed thickening and vegetation on the aortic valve and blood culture was positive for Staphylococcus epidermidis. The treatment with crystal penicillin and garamycin was initiated with no improval during three weeks. Endocarditis caused by human brucellosis was suspected and a new treatment with rifampicin and ciprofloxacin, associated with vancomycin because of the first blood culture, was initiated. Agglutination sorology was positive for brucellosis, with titers of 1:360. The patient got better with new treatment and was dismissed from the intensive care unit clinically stable, taking ciprofloxacin and gentamicin. CONCLUSIONS: Endocarditis caused by human brucellosis is rare; however it should always be considered when conservative antibiotic treatment fails, especially in patients that have contact with animals and dairy products.

Polyacrylic acid (PAA) is degraded in an aqueous medium with Fenton's reagent. At long reaction times, 17 hours at 60°C, acrylic acid polymer suffer decarboxylation with Fenton's reagent. At the end of the degradation process, the polymeric product has physically changed, becoming an amorphous smooth material. It has lost the initial crystallinity. The DSC data indicates polymer degradation with weight loss of volatile products as a consequence of the decarboxylation. Macroradial formation that experiments intercrossing reactions, forming a more stable structure, this is indicating by the lower weight loss percentage. At the same time, PAA with Fenton's reagent at 5 and 17 hours, presents an exoterm at 418 °C and 416 °C, respectively. This indicates volatile products degradation and macrostructure loose of the polymer