Resumen El potencial didáctico de los monolitos edafológicos es bien conocido en ámbitos relacionados con la Ciencia del Suelo; sin embargo, los eventos divulgativos sobre el suelo, aunque en auge, son todavía escasos. El Área de Edafología y Química Agrícola de la Escuela Técnica Superior de Ingenierías Agrarias de Palencia (Universidad de Valladolid) ha promovido la creación de una colección de monolitos de suelos característicos de las provincias de Palencia y Valladolid. Esta iniciativa surge con fines educativos, divulgativos y de sensibilización ambiental. Actualmente cuenta con dos mononolitos listos para ser expuestos junto con información adicional detallada. Su uso más inmediato será formar parte de una exposición sobre bosques y cambio climático en el Museo de la Ciencia de Valladolid, un evento integrado dentro del Proyecto “Ciencia en acción: Bosques y emergencia climática” (FECYT). En este contexto se pretende dar visibilidad al papel crucial de los suelos para combatir el cambio climático como secuestradores de CO2 entre un público no especializado. A corto plazo los monolitos se utilizarán en talleres de divulgación dentro de “La Noche Europea de los Investigadores” o la “Semana de la Ciencia de Castilla y León”, entre otros. Esta colección se irá ampliando en los próximos años y su uso se irá diversificando.

Abstract The didactic potential of soil monoliths is well known in areas related to soil science. However, informative events on soil, although on the rise, are still scarce. The Soil Science and Agricultural Chemistry Department of the Higher Technical School of Agricultural Engineering of Palencia (University of Valladolid) has promoted the creation of a collection of monoliths of characteristic soils from the provinces of Palencia and Valladolid. This initiative arises with educational, disseminative and environmental awareness purposes. There are currently two mononoliths ready to be exhibited along with additional detailed information. Its most immediate use will be to take part in an exhibition on forests and climate change at the Science Museum of Valladolid, an event integrated within the project "Science in action: Forests and climate emergency" (FECYT). In this context, the aim is to draw attention to the crucial role of soils in tackling climate change as CO2 sequestrators among a non-specialist public. In the short term, the monoliths will be used in outreach workshops as part of the "European Researchers' Night" or the "Castilla y León Science Week", among others. This collection will be expanded in the coming years and their use will be diversified.

Abstract The inappropriate disposal of toxic compounds generated by industrial activity has considerably impacted the environment. Microbial communities inhabiting contaminated sites may represent ecological alternatives for the decontamination of environments. The present work aimed to search the potential of fungi isolated from wastewater treatment plant of a textile industry for bioremediation processes. Twenty-three fungi previously isolated from textile effluent were evaluated for their abilities to degrade pollutants using heavy metal and hydrocarbon tolerance assays. One isolate was subjected to pyrene degradation due its ability to tolerate hydrocarbon. The majority of isolates were resistant to at least two metals tested, i.e. chrome, copper, lead and aluminum. Isolates Penicillium sp. ITF 2, Penicillium rubens ITF 4, Penicillium sp. ITF 12 and ITF 20 (not identified) showed tolerance to tested heavy metals in all concentrations. ITF 12 and ITF 20 were able to tolerate benzene, toluene and hexane, separately. ITF 12 was able to degrade 24.9% of pyrene after 5 days of cultivation. The results encourage future studies to optimize the tolerance and degradation assay using the isolates that showed the best results, as well as studies on the treatment of environments contaminated with heavy metals and hydrocarbons, including industrial textile effluents.

RESUMO Este estudo teve por objetivo avaliar o desenvolvimento ponderal e a dinâmica dos parâmetros hematológicos e bioquímicos de cordeiros Pantaneiros submetidos a diferentes manejos de amamentação dos 15 aos 43 dias. Foram separados 30 cordeiros em três diferentes grupos (n=10). Os grupos foram caracterizados conforme o tempo de permanência das ovelhas com suas crias em diferentes sistemas de amamentação: MAM24 - ovelhas e cordeiros 24 horas em conjunto; MAM12 - ovelhas e cordeiros 12 horas em conjunto durante a noite; MAM2x30 - ovelhas e cordeiros 30 minutos de manhã e 30 minutos à tarde em conjunto. As coletas de amostras sanguíneas e as pesagens ocorriam a cada sete dias. Houve aumento significativo no peso com o avanço da idade dos cordeiros nos três manejos, mas os tratamentos não diferiram entre si para o ganho de peso. Houve diferenças entre os três tratamentos para a variável hematológica CHGM e para as variáveis bioquímicas AST, glicose, ureia e proteína total. As variáveis bioquímicas foram influenciadas pela faixa etária dos animais. Os diferentes manejos de amamentação não influenciaram o desenvolvimento ponderal dos cordeiros. Não ocorreram alterações patológicas. Alguns parâmetros hematológicos e bioquímicos podem ser influenciados pelo desenvolvimento etário dos cordeiros.

ABSTRACT This study aimed to evaluate the weight development and the dynamics of hematological and biochemical parameters of Pantaneiro lambs submitted to different breastfeeding management from 15 to 43 days. First, 30 lambs were separated into three different groups (n = 10). The groups were characterized according to the length of stay of ewes with their young in different breastfeeding systems: MAM24 - ewes and lambs 24 hours together. MAM12- Sheep and lambs 12 hours together at night. MAM2x30 - sheep and lambs 30 minutes in the morning and 30 minutes in the afternoon together. Blood samples were collected and weighed every seven days. Significant increase in weight was observed with the age of the lambs in the three managements, but the treatments did not differ for weight gain. Differences were identified between the three treatments for the hematological variable CHGM and for the biochemical variables AST, glucose, urea and total protein. Correlating the age of the lambs with the biochemical variables, there was variation influenced by the age of the animals. The different management of breastfeeding did not influence the weight development of the lambs. Hematological and biochemical variations did not represent pathological changes. Some hematological and biochemical parameters may be influenced by the age development of lambs.

RESUMO: Este trabalho investigou as principais alterações clínicas e dermatopatológicas de equinos intoxicados natural e experimentalmente por Leucaena leucocephala. Os surtos ocorreram nos estados de São Paulo e Goiás, onde seis cavalos após a ingestão de casca e/ou folhas de L. leucocephala apresentaram alopecia, principalmente na crina e cauda. Nesses animais o diagnóstico foi baseado na observação da ingestão da planta e dos sinais clínicos. Nos animais intoxicados experimentalmente, foi realizado o exame clínico, biópsias da pele das regiões de crina, dorso e cauda e foi feita dosagem sérica de tri-iodotironina (T3) e tiroxina (T4). Alopecia da crina e cauda foi o principal sinal clínico observado, seguido de anorexia, emagrecimento e apatia em todos os equinos. Os níveis de T3 e T4 total apresentaram redução significativa (p≤0,05) na terceira semana de ingestão da leucena quando comparado aos níveis basais. As alterações histológicas observadas nas biópsias de pele demonstram acentuada telogenização dos folículos pilosos ao final dos experimentos. Os achados clínico-patológicos em equinos intoxicados são semelhantes aos observados em ruminantes. A intoxicação experimental de equinos por L. leucocephala evidenciou o acentuado declínio dos níveis dos hormônios tireoideanos, sugerindo efeito bociogênico da mimosina e seus compostos derivados, com hipotireoidismo transitório e alopecia devido à acentuada redução da atividade folicular.

ABSTRACT: This paper reports the main clinical changes of natural and experimentally poisoning by Leucaena leucocephala in horses. Outbreaks of poisoning occurred in São Paulo and Goiás States, where six horses after ingestion of bark and/or leaves of the plant showed alopecia mainly in mane and tail. The diagnosis was based on the observation of plant intake and clinical signs. In horses experimentally poisoned, clinical examination was performed and skin biopsies were taken from mane, back and tail regions, and triiodothyronine (T3) and thyroxine (T4) serum levels were assayed. Alopecia in mane and tail was the main clinical sign, accompanied by anorexia, weight loss and lethargy in all horses. T3 and total T4 showed significant decrease in serum levels (p≤0.05) in the third week of leucaena intake compared with baseline levels. Marked telogenization of hair follicles at the end of the experiments were observed in skin biopsies. The clinical and pathological findings in poisoned horses are similar to those observed in ruminants. Experimental poisoning of horses by the plant highlights the marked decline in levels of thyroid hormones, suggesting goitrogenic effect of mimosine and its derived compounds, with transient hypothyroidism and alopecia due to accentuated reduction in follicular activity.

RESUMO: A febre catarral maligna (FCM) é uma doença causada pela infecção de bovinos pelo herpesvírus ovino tipo 2 (OvHV-2), responsável por perdas econômicas em diferentes regiões do Brasil. Neste trabalho descreve-se a detecção molecular por nested-PCR (nPCR) do OvHV-2 em amostras de secreção/esfoliação nasal e fração celular sanguínea (FCS) de ovinos provenientes de 8 propriedades do Distrito Federal. Das 188 amostras nasais analisadas, 88 (41,5%) foram positivas. Ovelhas prenhes não apresentaram diferenças na taxa de infecção em comparação com fêmeas paridas. Fêmeas recém-paridas apresentaram taxa de infecção pelo OvHV-2 maior que em animais que pariram há mais de 60 dias. Amostras de secreção/esfoliação nasal permitiram a detecção por nPCR de animais infectados com uma eficiência aproximadamente duas vezes maior que em amostras de fração celular sanguínea. No Brasil, informações epidemiológicas sobre a infecção pelo OvHV-2 nos rebanhos ovinos e fatores envolvidos no surgimento de surtos de FCM em bovinos são escassos. Este estudo pode servir de subsídio para elucidar as características da enfermidade e para novos estudos sobre a epidemiologia da doença no Distrito Federal e em outros Estados do Brasil.

ABSTRACT: Malignant catarrhal fever (MCF) is a disease caused by bovine infection with ovine herpesvirus type 2 (OvHV-2) and responsible for economic losses in different Brazilian regions. This paper describes the molecular detection of OvHV-2 by nested-PCR (nPCR) in nasal secretion/exfoliation samples and blood cell fraction (BCF) of sheep from 8 properties in the Federal District. Among the 188 nasal samples, 88 (41.5%) were positive to OvHV-2. Pregnant ewe presented no differences at the infection rate in comparison with parous females. Newly calved sheep showed higher OvHV-2 infection rate than female over 60 days of calving. Nasal samples allowed the detection of infected animals by nPCR with efficiency about twice than that in the blood cell fraction samples. In Brazil, epidemiological information about OvHV-2 infection in sheep flocks and factors involved in emergence of FCM outbreaks in cattle are still scarce. This study may provide support for elucidating some characteristics of the disease and for further epidemiological studies in the Federal District and other Brazilian States.

Resumo As enfermidades que acometem a cavidade nasal de pequenos ruminantes podem causar prejuízos aos rebanhos de ovinos e caprinos na região central do Brasil. Foi realizado estudo retrospectivo dos laudos de necropsia do Laboratório de Patologia Veterinária da Universidade de Brasília (LPV-UnB) nos anos de 2003 a 2014 para verificar a ocorrência das doenças que acometeram a cavidade nasal de pequenos ruminantes. Foram analisados 463 protocolos de ovinos e 75 de caprinos totalizando 538 casos. Seis ovinos (6/463 1,29%) foram necropsiados com rinite granulomatosa micótica ou oomicótica e 22 animais do estudo (22/538; 4,08%) tiveram o diagnóstico de oestrose, sendo 86,36% ovinos e 13,64% caprinos. As rinites piogranulomatosas em ovinos ocorreram em áreas alagadas, com abundante material vegetal em decomposição. Os ovinos com pitiose rinofacial apresentaram como principais alterações aumento de volume na região nasal devido a extensas lesões granulomatosas associadas a necrose tecidual, caracterizadas por inúmeros macrófagos e polimorfonucleares circundando centros necróticos contendo o agente envolto por reação de Splendore-Hoeppli. Os ovinos com conidiobolomicose exibiram extensas áreas de necrose e inflamação piogranulomatosa, associadas à presença de hifas fúngicas na nasofaringe e também na região peribulbar e exoftalmia. A maioria dos animais com oestrose não apresentou alterações clínico-patológicas significativas, apesar de serem encontradas larvas principalmente nos seios e conchas nasais, traqueia e seio paranasal. A importância dessas enfermidades ainda é pouco conhecida na região, sendo de grande relevância que as condições clínico-patológicas e epidemiológicas sejam elucidadas para o diagnóstico, o controle e a prevenção, para evitar a expansão e prejuízos para os rebanhos.

Abstract Nasal cavity diseases that affect small ruminants can cause losses to sheep and goat herds in Central Brazil. A retrospective study of the University of Brasilia´s Veterinary Pathology Laboratory autopsy reports from 2003 to 2014 was conducted to verify the occurrence of small ruminants nasal cavity diseases. Six necropsied sheep (6/463 1.29%) showed mycotic or oomicotic granulomatous rhinitis and 22 animals (22/538, 4.08%) presented oestrosis diagnosis, affecting 86.36% of sheep and 13.64% of goats. The pyogranulomatous rhinitis in sheep occurred in flooded areas with abundant plant material decomposing. Rhinofacial pythiosis infection in animals showed as major changes swelling in the nasal region due to extensive granulomatous lesions associated with tissue necrosis, characterized by numerous macrophages and polymorphonuclear cells surrounding necrotic centers containing the agent surrounded by Splendore-Hoeppli reaction. Sheep with conidiobolomycosis showed extensive areas of necrosis and pyogranulomatous inflammation associated with fungal hyphae, localized in the nasopharynx and also in peribulbar region and exophthalmia. Most animals with oestrosis showed no significant clinical and pathological changes, even with the presence of larvae mainly in the sinuses and nasal turbinates, trachea and paranasal sinus. The importance of such diseases is still unknown in the region, and the knowledge of the clinical-pathological and epidemiological conditions is of great relevance for the diagnosis, control and prevention to avoid the expansion and losses to livestock.

Increasing volumes of synthetic polymers are manufactured for various applications, a way to address the problem of the polymer waste is by adding natural occurring polymers to a synthetic polymeric matrix. In this work, it was possible to extrude films of polyethylene (PE) with poly (lactic acid) (PLA) at any weight ratio; however, a range of 10 to 50 wt% PLA was selected.The results of tensile strength tests demonstrated a strong interaction of the chains of PE and poly (lactic acid) in the presence of 5 wt% of compatibilizer. Thermal analysis showed an improvement in thermal stability of the compatibilized films. SEM images showed a smooth and homogeneous surface in the films, regardless of the presence of the compatibilizer.The sensitivity to temperature, relative humidity, and solar radiation was evaluated for the films containing a 50 wt% of PLA in the polymeric matrix of PE; this was done through solar degradation experiments.

Una forma de abordar el problema de los residuos poliméricos que se generan es mediante la adición de polímeros de origen natural a una matriz polimérica sintética y de esta forma otorgarle una capacidad degradativa al material compuesto. En este trabajo, se extruyeron películas de polietileno con poli (ácido láctico) en un rango de 10 a 50% en peso de poli (ácido láctico).Los resultados de la caracterización mecánica demostraron una fuerte interacción de las cadenas de polietileno y poli (ácido láctico) en presencia de anhídrido maléico como compatibilizante. El análisis térmico mostró una mejora en la estabilidad térmica de las películas compatibilizados. Imágenes de microscopia electrónica de barrido mostraron una superficie lisa y homogénea en las películas.Las películas de polietileno y poli(ácido láctico) puro y las mezclas con 50% de poli(ácido láctico) fueron expuestas por 180 días a una degradación solar natural, con el objetivo de evaluar su sensibilidad a la temperatura, humedad relativa y radiación solar.

Foram utilizados 26 ovinos, entre 3 e 4 meses de idade, divididos em 3 grupos, provenientes de rebanhos que nunca tiveram contato com pastos de Brachiaria spp.. Dois grupos receberam Brachiaria decumbens no cocho diariamente ad libitum, sendo que um deles permaneceu em área com exposição solar (GS) e o outro foi mantido em baias cobertas protegidos do sol (GSB). O grupo controle (GC) foi também mantido em local com exposição solar e alimentado com feno de Cynodon dactylon e capim Pennisetum purpureum triturado. Todos os grupos receberam alimentação em cochos e foram suplementados com 200g/dia/animal de ração comercial para ovinos. Foi realizada a avaliação clínica diária dos ovinos e colhidas amostras duas vezes por semana para dosagem sérica de AST e GGT. Os animais que morreram foram submetidos a necropsia e em todos os ovinos sobreviventes foi realizada biópsia hepática no final do experimento. Três animais do grupo GS adoeceram e dois morreram. Um ovino do grupo GSB adoeceu e morreu. Não houve alterações clínicas nos ovinos controles. Os principais sinais clínicos observados nos animais que adoeceram foram apatia, emagrecimento, fotofobia, hiperemia e secreção ocular e icterícia. Nenhum animal apresentou lesões cutâneas de fotossensibilização. O grupo que permaneceu no sol apresentou atividades séricas médias de AST e GGT significativamente maiores que a dos demais grupos (p<0,05) e os animais que permaneceram na sombra apresentaram níveis maiores de GGT (p<0,05) em comparação ao grupo controle. A histopatologia das amostras de fígados dos ovinos com sinais clínicos demonstrou tumefação e vacuolização de hepatócitos, necrose individual de hepatócitos, macrófagos espumosos com cristais birrefringentes intracitoplasmáticos e dentro de ductos biliares e infiltrado mononuclear periportal. Amostras do capim fornecidas aos cordeiros evidenciaram níveis médios de 0,94±0,80% da saponina protodioscina. As observações do presente experimento sugerem que a não exposição ao sol não evita a presença de sinais clínicos da intoxicação, mas que a exposição solar exacerba os sinais clínicos.

Twenty-six five-month-old lambs originated from flocks with no previous contact with Brachiaria spp. pastures were divided into three groups. Two groups (GS and GSB) were fed daily with fresh harvested Brachiaria decumbens ad libitum. GS was kept in an area with solar exposure and GSB was kept in stalls sheltered from solar exposure. Control group (GC) was also kept under solar exposure, but fed with Cynodon dactylon grass hay and Pennisetum purpureum fresh grass. All sheep from the three groups were supplemented with 200g daily of a commercial concentrated food. Evaluation of clinical signs was carried out daily and blood samples were collected twice a week to determine AST and GGT serum activities. Three out of nine lambs of GS presented clinical signs of Brachiaria spp. poisoning, and two died. One animal showed clinical signs and died in GSB. The main clinical signs observed were apathy, weight loss, photophobia, conjunctivitis, ocular mucous discharge and jaundice. Dermatitis due to photosensitization was not observed. Mean serum AST and GGT activities were significantly higher (p<0,05) in the group exposed to sun, than in the other two groups, and the GGT activities were significantly higher in the group sheltered than in the control group (p<0,05). All animals at the end of the experiment were submitted to liver biopsy and died lambs were necropsied. Histopathological evaluation of liver samples from sheep with clinical signs evidenced swelling and vacuolization of hepatocytes, individual hepatocytes necrosis, presence of foamy macrophages, crystal negative images within bile ducts and foamy macrophages, biliary duct hyperplasia and periportal mononuclear infiltration. These results suggest that sun exposure does not define intoxication, but exacerbates the toxicity of the grass.

Avaliou-se a eficácia dos tratamentos, definidos pela International Embryo Transfer Society (IETS), de oócitos bovinos, maturados in vitro e expostos experimentalmente à Leptospira interrogans sorovar Grippotyphosa. Os oócitos foram obtidos por meio de punção folicular, selecionados e distribuídos em quatro grupos, expostos ao patógeno e submetidos aos diferentes tipos de tratamentos. Foram expostos à cepa na concentração de 4,7.10(5)/µL, virulenta e não adaptada ao meio de manutenção EMJH, e, de 6,3.10(5)/µL, avirulenta e adaptada ao meio, por 24 horas. Os grupos tratados com tripsina ou antibióticos apresentaram eficácia de 21,7%, e o grupo lavado sequencialmente 33,4%. Os tratamentos não foram eficazes para os contaminados com a cepa avirulenta. Concluiu-se que as normas de controle de qualidade estabelecidas pela IETS poderiam ser revisadas e, possivelmente, redefinidas, uma vez que a eficácia dos tratamentos, provavelmente, não depende somente da espécie do patógeno, pois há interferência da virulência e de ação dos tratamentos sobre o tipo de patógeno.

The research purpose was to evaluate the effectiveness of treatments established by the IETS, in bovine oocytes maturated in vitro, exposed experimentally to Leptospira interrogans serovar Grippotyphosa. The oocytes were obtained through follicular puncture, selected and randomly allotted in four groups, exposed to the pathogen and subjected to different types of treatments. They were exposed to the strain in the concentration of 4.7x10(5)/µL virulent and not adapted to the EMJH, and to 6,3x10(5)/µL, virulent and adapted to the medium, for 24 hours. The treatments presented for the groups with trypsin or antibiotics, 21.7% efficiency, and the group washed sequentially presented 33.4% efficiency. The treatments were not effective for those infected with avirulent strain. In the statistical analysis, by χ², was found significance in the results obtained. The standards of quality control established by IETS could be reviewed and possibly redefined, since the effectiveness of treatment probably depends not only on the species of the pathogen, but is also affected by its virulence and treatment effectiveness.

Avaliou-se o efeito da endotoxemia sobre a atividade antioxidante de macrófagos alveolares em ratos da linhagem Wistar. Foram utilizados 24 ratos machos, com idade entre 90 e 120 dias, os quais foram divididos em dois grupos: controle e endotoxêmico. O grupo endotoxêmico foi submetido à injeção intraperitonial de lipopolissacarídio na dose de 1mg/kg de peso corporal. Após 24 h, coletou-se sangue para contagem total e diferencial de leucócitos; lavado broncoalveolar para contagem total e diferencial dos leucócitos e, a partir de macrófagos isolados deste lavado, foram realizadas as dosagens de superóxido e superóxido dismutase. A endotoxemia aumentou a contagem total de leucócitos e o número de neutrófilos no sangue periférico, no lavado broncoalveolar, e aumentou a produção de superóxido sem modificar a produção da superóxido dismutase. Esses resultados sugerem que a endotoxemia induz a uma resposta inflamatória no pulmão. Contudo, não altera a atividade antioxidante em ratos adultos. Tal fato potencializa a resposta contra agentes infecciosos pelo hospedeiro, mas também pode contribuir na patogênese de injúria pulmonar.

The effects of endotoxemia on the antioxidant activity in alveolar macrophages of Wistar rats were evaluated. Twenty-four male rats, 90-120 days of age, were separated into 2 groups: control and endotoxemic. To the endotoxemic animals was administered, intraperitoneally, a lipopolyssaccaride at dosage of 1mg/kg body weight. Twenty-four hours after this procedure, blood was collected for total and differential leukocytes counts. In addition, bronchoalveolar lavage was collected for total and differential leukocyte counting. From this lavage macrophages were isolated for the dosage of superoxide and superoxide dismutase. The endotoxemia increased the total leukocyte counts and the number of neutrophils in the peripheral blood and bronchoalveolar lavage of the rats. There was an increased superoxide production without changing the superoxide dismutase. Our findings indicate that endotoxemia induces lung inflammatory response. However, it does not alter the antioxidant activity in adult rats. This fact not only enhances host response against infectious agents, but might also contribute to the pathogenesis of pulmonary injury.

Se determinó la carga de sedimentos en suspensión (SS) y fósforo (P) durante eventos de lluvia-escorrentía en un arroyo de cabecera, que drena una cuenca rural ubicada en Galicia (NO España). Asimismo, se trató de conocer las principales fuentes de SS y P exportados. Se observaron acusadas diferencias en la carga de SS y P entre eventos, lo cual se asocia con el volumen de escorrentía, así como con el desarrollo de surcos y cárcavas efímeras en parcelas de cultivo bien conectadas con la red de drenaje. La carga de SS osciló entre 0,8 y 21,0 t mientras que la de P varió entre 2,5 y 20,0 kg. El fósforo particulado (PP) mostró relaciones significativas con los SS, lo que indica el origen erosivo de una parte importante de P, especialmente considerando que el PP supone más de un 80% del P exportado en cada evento.

This work examines the suspended sediment (SS) and phosphorus (P) load during rainfall-runoff events in a headwater stream which drains a rural catchment located in Galicia (NW Spain). Another objective is to know the major sources of SS and P exported. Important differences in the SS and P load between events were found, which is associated with the runoff volume, as well as to develop of rills and ephemeral gullies in cultivated fields well connected to the drainage network. The SS load ranged between 0.8 and 21.0 t, while the P load varied between 2.5 and 20.0 kg. The particulate phosphorus (PP) showed significant relationship with SS, which indicates the erosive origin of P, especially considering that PP means more 80% of P exported each event.

Interfacial dielectric relaxation has been studying in composite materials made with epoxy resin and aluminum. Electric modulus, which has been proposed for the description of systems with relaxation process, presents advantages in comparison to the classic approach of the real and imaginary part of dielectric permittivity. In composite polymer materials, relaxation phenomena at the low frequency region are attributed to the heterogeneity of the system. Epoxy was diluted using tetrahydrofuran as solvent in order to reduce matrix viscosity and to facilitate the mixing step. The fillers were mixed with the resin using an ultrasonic mixer during 4 minutes. The composites were prepared pouring them into suitable moulds and cured at 100ºC for 2 hours. Density was measured by the Arquimedes method and real volume fraction of each composite was found by termogravimetric analysis. Dielectric measurements were performed from 25 Hz to 1 MHz and 20 ºC to 120 ºC. It was found that the epoxy - aluminum composites had higher permittivity and a strong dependence with filler concentration. Relaxation processes were influenced by the epoxy resin near their Tg, while metal content modified the real permittivity values. Interfacial polarisation processes known as Maxwell-Wagner-Sillar were generated by particles. This process is attributed to the accumulation of charges on the interface that helped to displace peaks to higher frequencies.

En este trabajo se estudiaron los fenómenos de relajación de materiales compuestos polímero/metal en función de la cantidad de partículas de metálicas incorporadas (aluminio). El concepto de módulo eléctrico fue empleado para analizar los procesos de relajación tipo Debye y Maxwell-Wagner-Sillar, debido a que presenta varias ventajas con respecto al análisis clásico de la parte real (ε') e imaginaria (ε") de la permitividad. El material compuesto se obtuvo por colada y posterior curado a 100ºC por 2 horas, previa mezcla en un mezclador ultrasónico de ambos componentes. La densidad de las muestras se determinó por el método de Arquímedes, mientras que las fracciones en volumen se establecieron mediante termogravimetría. Las mediciones de propiedades dieléctricas se realizaron en el rango de frecuencias de 25Hz a 1Mhz y temperatura de 30 a 120ºC. Por último, la microestructura fue observada mediante Microscopía Electrónica de Barrido. Las micrografías revelaron que la incorporación del metal no incrementó en forma significativa la cantidad de defectos o la porosidad. Los resultados del análisis dieléctrico mostraron que los materiales poseen muy buenas propiedades dieléctricas a bajas temperaturas, y que los fenómenos de relajación son propios de la resina y modificados por la influencia de las cargas metálicas debido a fenómenos de relajación interfacial tipo MWS.

O estudo avaliou a contaminação microbiológica e parasitológica de 88 hortas produtoras de verduras, das quais 47 haviam sido investigadas anteriormente. A taxa de contaminação foi de 38,3% nas hortas previamente investigadas e de 43,9% nas novas hortas. A segurança alimentar requer um contínuo e eficiente sistema de vigilância sanitária das hortas.

This study evaluated the microbiological and parasitological contamination of 88 market gardens producing green vegetables, of which 47 had been investigated previously. The contamination rate was 38.3% in the market gardens previously evaluated and 43.9% in the new market gardens. Food safety requires a continuous and efficient sanitary surveillance system for market gardens.

We have shown that myocardial dysfunction induced by food restriction is related to calcium handling. Although cardiac function is depressed in food-restricted animals, there is limited information about the molecular mechanisms that lead to this abnormality. The present study evaluated the effects of food restriction on calcium cycling, focusing on sarcoplasmic Ca2+-ATPase (SERCA2), phospholamban (PLB), and ryanodine channel (RYR2) mRNA expressions in rat myocardium. Male Wistar-Kyoto rats, 60 days old, were submitted to ad libitum feeding (control rats) or 50% diet restriction for 90 days. The levels of left ventricle SERCA2, PLB, and RYR2 were measured using semi-quantitative RT-PCR. Body and ventricular weights were reduced in 50% food-restricted animals. RYR2 mRNA was significantly decreased in the left ventricle of the food-restricted group (control = 5.92 ± 0.48 vs food-restricted group = 4.84 ± 0.33, P < 0.01). The levels of SERCA2 and PLB mRNA were similar between groups (control = 8.38 ± 0.44 vs food-restricted group = 7.96 ± 0.45, and control = 1.52 ± 0.06 vs food-restricted group = 1.53 ± 0.10, respectively). Down-regulation of RYR2 mRNA expressions suggests that chronic food restriction promotes abnormalities in sarcoplasmic reticulum Ca2+ release.

RESUMO Pesquisou-se anticorpos anti Mycoplasma gallisepticum (MG) e Mycoplasma synoviae (MS) nas populações de aves de produção não tecnificada e com finalidade de subsistência, em propriedades rurais em áreas geográficas próximas a granjas de reprodutoras (matrizeiros) do Estado de São Paulo. Foram selecionadas quinze criações vizinhas a 3 granjas de matrizes, consideradas livres de MG e MS. Soros sanguíneos de 406 galinhas foram estudados quanto a presença de anticorpos anti MG e MS. A avaliação foi realizada pela técnica de soroaglutinação rápida em placa. As freqüências de positividade encontradas foram de 73% e 100% das aves aos antígenos de MG e MS, respectivamente. As ocorrências observadas de aves sororreagentes foram de 30,3% e 40,6% para os antígenos de MG e MS, respectivamente. Os resultados indicaram que MG e MS estão amplamente difundidos nas criações informais de aves de “fundo de quintal”, colocando em risco constante os criatórios de exploração industrial, os quais necessitam adotar e manter boas práticas de biossegurança para preservar a integridade sanitária dos plantéis.

ABSTRACT This investigation aimed to demonstrate the occurrence of serological reactions to Mycoplasma gallisepticum and Mycoplasma synoviae in domestic backyard poultryfor self consumtion located next to parent flocks in the State of São Paulo. Fifteen backyard flocks around 3 parent flocks officially recognized as free from MG and MS were selected.Sera from 406 chickens were researched on antibodies anti MG and MS, by means of plate agglutination test. The frequencies found were 73% and 100% of flocks with chickens reacting to the antigens of MG and MS, respectively. The frequencies of reacting chickens were 30.3% and 40.6% for the antigens of MG and MS, respectively. The results showed that the aetiological agents studied are widespread among the backyard flocks, posing a constant risk for the commercial poultry flocks, which need to adopt and keep good biosecurity practices to preserve their sanitary status.