994 resultados para anti-skid mat


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The use of lashing means, for example load securing straps or nets, is often time-consuming, especially for courier, express and parcel-services (CEP) using a lot stops. The following article describes the development of an automated load securing system with a three-dimensional-preformed net. Mainly two components interact in this system. On the one hand, an anti-skid system is integrated, which uses the advantages of a low-friction surface for loading and the anti-slip properties of an adhesive coating for the transport. On the other hand, a flexibly adaptive net consisting of high-performance synthetic fibers and integrated shorteners lash different sized transport units. Especially, the automatic lashing should increase the acceptance of the drivers for the new load securing system.

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Vehicles affect the concentrations of ambient airborne particles through exhaust emissions, but particles are also formed in the mechanical processes in the tire-road interface, brakes, and engine. Particles deposited on or in the vicinity of the road may be re-entrained, or resuspended, into air through vehicle-induced turbulence and shearing stress of the tires. A commonly used term for these particles is road dust . The processes affecting road dust emissions are complex and currently not well known. Road dust has been acknowledged as a dominant source of PM10 especially during spring in the sub-arctic urban areas, e.g. in Scandinavia, Finland, North America and Japan. The high proportion of road dust in sub-arctic regions of the world has been linked to the snowy winter conditions that make it necessary to use traction control methods. Traction control methods include dispersion of traction sand, melting of ice with brine solutions, and equipping the tires with either metal studs (studded winter tires), snow chains, or special tire design (friction tires). Several of these methods enhance the formation of mineral particles from pavement wear and/or from traction sand that accumulate in the road environment during winter. When snow and ice melt and surfaces dry out, traffic-induced turbulence makes some of the particles airborne. A general aim of this study was to study processes and factors underlying and affecting the formation and emissions of road dust from paved road surfaces. Special emphasis was placed on studying particle formation and sources during tire road interaction, especially when different applications of traction control, namely traction sanding and/or winter tires were in use. Respirable particles with aerodynamic diameter below 10 micrometers (PM10) have been the main concern, but other size ranges and particle size distributions were also studied. The following specific research questions were addressed: i) How do traction sanding and physical properties of the traction sand aggregate affect formation of road dust? ii) How do studded tires affect the formation of road dust when compared with friction tires? iii) What are the composition and sources of airborne road dust in a road simulator and during a springtime road dust episode in Finland? iv) What is the size distribution of abrasion particles from tire-road interaction? The studies were conducted both in a road simulator and in field conditions. The test results from the road simulator showed that traction sanding increased road dust emissions, and that the effect became more dominant with increasing sand load. A high percentage of fine-grained anti-skid aggregate of overall grading increased the PM10 concentrations. Anti-skid aggregate with poor resistance to fragmentation resulted in higher PM levels compared with the other aggregates, and the effect became more significant with higher aggregate loads. Glaciofluvial aggregates tended to cause higher particle concentrations than crushed rocks with good fragmentation resistance. Comparison of tire types showed that studded tires result in higher formation of PM emissions compared with friction tires. The same trend between the tires was present in the tests with and without anti-skid aggregate. This finding applies to test conditions of the road simulator with negligible resuspension. Source and composition analysis showed that the particles in the road simulator were mainly minerals and originated from both traction sand and pavement aggregates. A clear contribution of particles from anti-skid aggregate to ambient PM and dust deposition was also observed in urban conditions. The road simulator results showed that the interaction between tires, anti-skid aggregate and road surface is important in dust production and the relative contributions of these sources depend on their properties. Traction sand grains are fragmented into smaller particles under the tires, but they also wear the pavement aggregate. Therefore particles from both aggregates are observed. The mass size distribution of traction sand and pavement wear particles was mainly coarse, but fine and submicron particles were also present.

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Besonders für Kurier-Express-Paket-Dienste (KEP) mit vielen Haltepunkten sind verfügbare Mittel zur Ladungssicherung, wie z.B. Sicherungsnetze oder Sicherheitsgurte viel zu zeitaufwendig in der Anwendung. Im vorliegenden Artikel wird die Entwicklung eines automatisierten Ladungssicherungssystems mit dreidimensionalem-vorgeformten Sicherungsnetz vorgestellt. Für die Ladungssicherung wirken zwei Kernkomponenten zusammen. Zum einen ist ein Antirutschsystem integriert, welches die Vorteile einer reibarmen Oberfläche zum Beladen und die rutschhemmende Wirkung eines haftenden Belags beim Transport ausnutzt. Zum anderen werden unterschiedlich große Transporteinheiten durch ein sich flexibel anpassendes Netz überspannt, welches aus hochfestem Material, mit integrierten Netzverkürzern besteht. Die automatische Bedienbarkeit soll vor allem bei den Fahrern die Akzeptanz für das Ladungssicherungssystem erhöhen.

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The study evaluated the efficiency of diagnostic laboratory methods to detect anti-Toxoplasma gondii antibodies in paired serum and aqueous humour samples from experimentally infected pigs. 18-mixed breed pigs were used during the experiment; these were divided into two groups, G1 (infected group, n = 10) and G2 (uninfected group, n = 8). Infection was performed with 4 × 10 4 VEG strain oocysts at day 0 by the oral route in G1 animals. All pigs were euthanized at day 60, when retina, aqueous humour, and blood samples were collected. Anti-T. gondii antibody levels were assessed in serum (s) and aqueous humour (ah) by indirect immunofluorescence assay (IFA), modified agglutination test (MAT), m-ELISA (using crude membranes from T. gondii tachyzoites as antigen) and r-ELISA (using rhoptries from T. gondii tachyzoites as antigen). Polymerase chain reactions (PCR) of samples from the retina were performed by using Tox4 and Tox5 primers. Antibody titers of G1 animals ranged from 128 to 1024 and from 16 to 256 in serum and aqueous humour, respectively. There were differences in the correlation coefficients between IFA(s) × IFA (ah) (r = 0.62, P = 0.05), MAT(s) × MAT (ah) (r = 0.97, P < 0.0001); however, there was no significant difference between r-ELISA(s) × r-ELISA (ah) (r = 0.14, P = 0.7). Antibodies present in serum and aqueous humour recognized similar antigens. Samples of retina were positive by PCR in 30% (3/10) of infected pigs. G2 animals remained without antibody levels and were PCR negative throughout the experiment. These results suggest that the use of a combination of tests and immunoblotting for paired aqueous humour and serum samples could improve the sensitivity and specificity for the diagnosis of ocular toxoplasmosis. © 2007 Elsevier Ltd. All rights reserved.

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Perturbations of asymptotically Anti-de-Sitter (AdS) spacetimes are often considered by imposing field vanishing boundary conditions (BCs) at the AdS boundary. Such BCs, of Dirichlet-type, imply a vanishing energy flux at the boundary, but the converse is, generically, not true. Regarding AdS as a gravitational box, we consider vanishing energy flux (VEF) BCs as a more fundamental physical requirement and we show that these BCs can lead to a new branch of modes. As a concrete example, we consider Maxwell perturbations on Kerr-AdS black holes in the Teukolsky formalism, but our formulation applies also for other spin fields. Imposing VEF BCs, we find a set of two Robin BCs, even for Schwarzschild-AdS black holes. The Robin BCs on the Teukolsky variables can be used to study quasinormal modes, superradiant instabilities and vector clouds. As a first application, we consider here the quasinormal modes of Schwarzschild-AdS black holes. We find that one of the Robin BCs yields the quasinormal spectrum reported in the literature, while the other one unveils a new branch for the quasinormal spectrum.

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The aim of this study was to determine the prevalence of anti-Leptospira spp. antibodies in dogs living in the urban area of the city of Ilheus, Bahia, Brazil using the microscopic agglutination test (MAT) to investigate 24 serovars. A semi-structured questionnaire was administered to dog owners to collect data about demography, husbandry and environmental factors. The prevalence of anti-Leptospira spp. antibodies in the population of 282 dogs was 7.1% (95% confidence interval: 4.4-10.7%). Serovar Copenhageni was the most prevalent, followed by serovars Bratislava, Canicola and Gryppotyphosa. No risk factor was detected with regard to demography (age, gender and breed), husbandry (Leptospira vaccinations, food and water exposure through their environment, hunting habits, contact with other animals and contact with rats) and environmental factors (sewage network, garbage collection, history of flooding, river proximity and wastelands). Despite the low prevalence found in this study, the seroprevalence of Leptospira spp. in healthy dogs in Ilheus indicates the presence of this agent in the environment, which may be a source of human infection. Knowledge of the serovars present in this environment is important for understanding the epidemiology of leptospirosis and establishing public health policies aimed at its control. (C) 2012 Elsevier B.V. All rights reserved.

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The rate of anti-Toxoplasma gondii antibodies was evaluated in equines, cats, dogs, poultry, pigs, cattle and sheep of farms in Eldorado, southern Mato Grosso do Sul. Blood samples were collected and sera were examined by the modified agglutination test (MAT), considering positives samples reactants with titers >= 25. Rates of reactor animals in the antibody detection test were: 22.89% (46/201) in poultry, 5.15% (20/388) in cattle, 47.61% (20/42) in dogs, 60.87% (14/23) in equines, 57.14% (8/14) in cats, 14.7% (5/34) in pigs. None of the sheep (0/14) were positive. High antibody rates were found in several species, a fact that raise concerns due to the possibility of risk to humans, once these animal species either share the same source of infection with humans or are food sources for them.

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Leptospirosis is a worldwide infection, transmitted between man and animals that causes a decrease in the production of bovine flocks, and offer risks for public health, as an important zoonosis. The rodents are the main reservoirs of leptospires. It was studied 27 dairy farm properties located in or near from Botucatu-SP, Brazil. In these farms were collected blood and kidney samples from rodents, blood and urine samples from bovines and blood samples from the workers. The serology was performed with microscopic agglutination test (MAT). Samples of bovine urine and rodent kidneys were cultivated searching for leptospires isolation. The polymerase chain reaction (PCR) of the kidneys of the rodents was performed. In MAT, 46/ 140 (32.85%) bovine and 8/34 (23.53%) human sera samples were positive, respectively. In human samples, the serovar Brastilava (37.51%) presented the highest occurrence, while in bovines, the serovars Hardjo and Castellonis were most frequent, with 26.08% each one. All of the rodents were negatives in serology. No leptospire was isolated, and kidney samples were negative in PCR. In bovines, the dam water and the bad hygiene quality of milking process were considered important risks of infection in the affected properties (p<0.05), where other reproductive problems, except abortion, can be related. In other side, to human beings the drainage system was the most important risk factor in the studied properties. Thus, it was verified the necessity of an improvement in zoosanitary handling of the properties, mainly of water supply.

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Indirect ELISA and IFAT have been reported to be more sensitive and specific than agglutination tests. However, MAT is cheaper, easier than the others and does not need special equipment. The purpose of this study was to compare an enzyme linked immunosorbent assay using crude rhoptries of Toxoplasma gondii as coating wells (r-ELISA) with indirect fluorescence antibody test (IFAT) and modified agglutination test (MAT) to detect anti-T. gondii antibodies in sera of experimentally infected pigs. Ten mixed breed pigs between 6.5 and 7.5 weeks old were used. All pigs were negative for the presence of T. gondii antibodies by IFAT (titre < 16), r-ELISA (OD < 0.295) and MAT (titre < 16). Animals received 7 × 107 viable tachyzoites of the RH strain by intramuscular (IM) route at day 0. Serum samples were collected at days -6, 0, 7, 14, 21, 28, 35, 42, 50, and 57. IFAT detected anti-T. gondii antibodies earlier than r-ELISA and MAT. The average of antibody levels was higher at day 35 in IFAT (Log10 = 2.9) and in MAT (Log10 = 3.5), and at day 42 in r-ELISA (OD = 0.797). The antibody levels remained high through the 57th day after inoculation in MAT, and there was a decrease tendency in r-ELISA and IFAT. IFAT was used as gold standard and r-ELISA demonstrated a higher prevalence (73.3%), sensitivity (94.3%), negative predictive value (83.3%), and accuracy (95.6%) than MAT. Kappa agreements among tests were calculated, and the best results were shown by r-ELISA × IFAT (κ = 0.88, p < 0.001). Cross-reaction with Sarcocystis miescheriana was investigated in r-ELISA and OD mean was 0.163 ± 0.035 (n = 65). Additionally, none of the animals inoculated with Sarcocystis reacted positively in r-ELISA. Our results indicate that r-ELISA could be a good method for serological detection of T. gondii infection in pigs. © 2005 Elsevier Inc. All rights reserved.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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A toxoplasmose é uma zoonose causada pelo Toxoplasma gondii, comum nos animais domésticos e que tem sido objeto de estudos no Brasil e em todas as partes do mundo. Este parasita intracelular obrigatório infecta mamíferos e aves e tem nos felídeos seus hospedeiros definitivos. Nas aves, a infecção toxoplásmica pode ser assintomática, a forma mais provável de contaminação é através da ingestão de oocistos presentes no solo, água e rações contaminadas e a carne de frangos uma das principais vias de transmissão para o homem. Com objetivo de estudar a ocorrência de anticorpos anti-Toxoplasma gondii em frangos de corte abatidos para consumo na região metropolitana de Belém, 300 amostras de soro procedentes de abate em escala industrial e clandestino, foram submetidas ao Teste de Aglutinação Modificada (MAT). Anticorpos anti-T. gondii foram detectados em uma (1/300, 0,33%) amostra, procedente de abate clandestino e em nenhuma amostra procedente de abate em escala industrial. Embora as amostras de soro de frangos de corte procedentes de abate em escala industrial não tenham demonstrado anticorpos anti-T. gondii, recomenda-se a adoção rotineira de pesquisa sorológica desse organismo em qualquer tipo de abate e no nível de consumo como medida de prevenção ao risco sanitário humano e estudos para determinar a real importância das galinhas de criação livre na epidemiologia da toxoplasmose em nosso meio.

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A toxoplasmose, uma das zoonoses mais difundidas no mundo, é causada pelo Toxoplasma gondii, um protozoário que tem os felídeos como únicos hospedeiros definitivos. Avaliou-se 21 animais de quatro espécies, gato-mourisco (Herpailurus yaguarondi), jaguatirica (Leopardus pardalis), gato-maracajá (Leopardus wiedii), onça-pintada e preta (Panthera onca) a fim de averiguar a situação da toxoplasmose em dois municípios do estado do Pará, utilizando dois testes sorológicos, a hemaglutinação indireta (HAI) e aglutinação direta modificada (MAT), além de exame coproparasitológico. Dos animais testados, 18 (85,72%) foram positivos. Doze (57,14%) animais foram soropositivos pela técnica HAI e, 14 (66,66%) pela técnica MAT. Não houve diferença estatística entre a soropositividade e os gêneros, nas duas técnicas utilizadas. No gênero Herpailurus encontrou-se 4,6% de soropositividade em ambos os testes; no Leopardus, 19,05% na HAI e 28,57% na MAT; e, no Panthera, 33,33% nas duas técnicas. Foi constatado resultado coincidente em 11 animais. Comparando-se as duas técnicas, não houve diferença estatística. A titulação mais alta foi verificada em um gato-maracajá (1024), na MAT. Não foi encontrado oocisto de T. gondii nas fezes de nenhum dos animais estudados. Verificou-se que há uma alta ocorrência da toxoplasmose nos municípios estudados e que ambas as técnicas utilizadas são eficazes no diagnóstico sorológico desta doença.

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The sheep industry has become increasingly prominent in agribusiness, transforming the stage production of Brazil, and thus contributes more to the socio-economic development of the country. The work aimed to verify the occurrence of brucellosis and leptospirosis in sheep from northwestern São Paulo state. In addition to determining the prevalence of major Leptospira in the region and to trace the diagnosis of sheep breeding in this part of the country. All the 1222 sheep serum samples from 49 properties did not react serologically to evidentiary testing for brucellosis, compared to antigens of B. abortus and B. ovis used in the testing of 2-ME and IDGA, respectively. The Microscopic Agglutination Test (MAT) test revealed that 19.14% (232/1212) of samples were positive for one or more serovars, with titles ranging from 100 to 800. The most frequent serovar was hebdomadis in the region, with Sentot and Sherman (18.10%, 11.64% and 8.62%, respectively). By profiling the system of sheep farming in the region, we found that most herds are composed of more than one race being the main purpose is for the court. According to the scheme adopted immunoprophylactics there is a homogeneous set schedule. It adopts the use of anti-helminth, non-prescription veterinary antibiotic. There is also the presence of diarrhea and abortions and the lack of criteria for los ovinos on management, making it the need for emergency development of programs for disease control, schema immunoprophylactics adequate sanitation and hygienic measures in sheep breeding.