Adhesion attenuation and enhancement in aqueous solutions

When two surfaces confine water layers between them at the nanoscale, the behaviour of these confined water molecules can deviate significantly from the behaviour of bulk water, and it could reflect on the adhesion of such surfaces. This study assesses the role of confined water layers on the adhesion of hydrophilic surfaces and how sensitive this adhesion is to the presence of contaminants. Our methodology used atomic force microscopy adhesion measurements, whereby an alumina-sputtered sphere-tipped cantilever was interacted versus a flat alumina single crystal. Testing was performed under immersed conditions using (i) water, (ii) water/dimethylformamide mixtures, (iii) water/ethanol mixtures, and (iv) water/formamide mixtures. These solutions were intended to assess the influence of dielectric constant, molecule size, and the number of hydrogen bonding opportunities available to molecules upon confinement between surfaces. It was found that dilute concentrations of ethanol and formamide decreased the adhesion. In contrast, the adhesion increased in the presence of dilute concentrations of dimethylformamide. The adhesion was attenuated by in excess of two orders of magnitude for high concentrations of the organic solutes

Interactive Search and Exploration in Online Discussion Forums Using Multimodal Embeddings

In this paper we present a novel interactive multimodal learning system, which facilitates search and exploration in large networks of social multimedia users. It allows the analyst to identify and select users of interest, and to find similar users in an interactive learning setting. Our approach is based on novel multimodal representations of users, words and concepts, which we simultaneously learn by deploying a general-purpose neural embedding model. We show these representations to be useful not only for categorizing users, but also for automatically generating user and community profiles. Inspired by traditional summarization approaches, we create the profiles by selecting diverse and representative content from all available modalities, i.e. the text, image and user modality. The usefulness of the approach is evaluated using artificial actors, which simulate user behavior in a relevance feedback scenario. Multiple experiments were conducted in order to evaluate the quality of our multimodal representations, to compare different embedding strategies, and to determine the importance of different modalities. We demonstrate the capabilities of the proposed approach on two different multimedia collections originating from the violent online extremism forum Stormfront and the microblogging platform Twitter, which are particularly interesting due to the high semantic level of the discussions they feature

Redução da viabilidade de esporângios de Plasmopara viticola por bactérias nativas do filoplano da videira.

Resumo: O míldio é uma das principais doenças da videira, capaz de causar danos significativos à cultura e aumentar os custos de produção. Seu controle demanda o uso intensivo de agrotóxicos, cujos resíduos são indesejáveis. Este trabalho teve como objetivo investigar o potencial uso de bactérias do filoplano em reduzir a viabilidade de esporângios de Plasmopara viticola. Foram testados trinta e cinco isolados bacterianos obtidos do filoplano de videira. Os testes de antagonismo foram feitos em lâminas de microscopia e em discos de folha, adicionando-se 50 microL de uma suspensão bacteriana e 50 microL de uma suspensão de esporângios. Nos testes em lâmina de microscopia, vinte e nove isolados inibiram a germinação dos esporângios de Plasmopara viticola. Destes, os isolados 1, 37 e 12 se destacaram, por serem capazes de inibir também a liberação de zoósporos. Em discos de folha, o isolado 1 foi o único capaz de inibir a liberação dos zoósporos, significativamente em relação à testemunha. Nesta condição, não houve a germinação dos esporângios, apenas a liberação de zoósporos. Abstract: The downy mildew is one of the main grapevine diseases, able to cause significant damage to the crop and increase production costs. It?s control demand intensive use of pesticides, which residues are undesirable. This study aimed to investigate the potential of phylloplane bacteria in reducing the viability of sporangia of Plasmopara viticola. Thirty-five bacterial isolates from phylloplane of grapevine were tested. The antagonism tests were conducted on microscopy glass blades and on leaf discs, adding microL of a bacterial suspension and 50 microL of a suspension of sporangia. Twenty-nine isolates inhibited the germination of the sporangia of Plasmopara viticola in tests conducted on glass blades. Of these, isolates 1, 37 and 12 were able to inhibit the release of zoospores. In the leaf discs test, the isolate 1 was the single able to inhibit the release of zoospores, significant compared to the control. In this condition, there wasn?t germination of sporangia, only zoospores release

Tuberculosis/HIV/AIDS coinfection in Porto Alegre, RS/Brazil - invisibility and silencing of the most affected groups

OBJECTIVE: To analyze how belonging to certain social groups contributes to constituting the vulnerabilities associated with illnesses due to tuberculosis/HIV/AIDS coinfection. METHODOLOGYThis is a qualitative study carried out in the city of Porto Alegre, state of Rio Grande do Sul, in regions of high social vulnerability. Twenty coinfected people were interviewed in specialized health services between August and December 2016. The analysis was based on the frameworks The Sound of Silence and Vulnerability and Human Rights. RESULTS: Socioeconomic conditions were decisive for the constitution of the vulnerability conditions. Processes of people invisibilization, and the silencing of their voices, in a scenario marked by economic, racial and gender inequalities, contributed for their health needs not to be understood and effectively taken into account in the services actions. FINAL CONSIDERATIONS: The more effective strategies are to legitimize voices and to understand the needs of those affected by coinfection, the greater the chances that programmatic responses to the problem will be successful

Manutenção em campo de níveis variados de palhada de cana-de-açúcar: efeitos sobre o acúmulo de nitrogênio nas plantas.

Resumo: O objetivo do trabalho foi estudar a contribuição de diferentes níveis de palhada sobre o acumulo de nitrogênio na cana-de-açúcar. O ensaio foi instalado em Araras-SP, durante as safras de 2011-12 e 2012-13 (variedade RB-845210). Foram aplicados cinco tratamentos, com níveis de 0%, 25%, 50%, 75% e 100% (0 - 2,8- 5,7- 8,5 -11,3 t ha-1 safra 2011-12) (0 - 3 - 6,2 - 9,4 - 12,8 t ha-1 safra 2012-13) dispostos em blocos ao acaso com quatro repetições. Para acompanhar o acumulo de N nos diferentes compartimentos da planta (folhas verdes, folhas secas e colmo) de cana-de-açúcar foram utilizados os dados de massa seca (kg ha-1) e concentrações de N (g kg-1) de cada um destes componentes, obtidos em biometrias realizadas ao longo dos dois ciclos de cultivos estudados. Utilizou-se a análise de variância e regressão para o tratamento estatístico dos resultados. Foi possível concluir que: a manutenção de quantidades de palhada entre 5-12 t ha-1 promovem o mesmo acúmulo de nitrogênio no colmo em relação à ausência deste resíduo (sem palhada) somente após dois ciclos de cultivo de cana-de-açúcar; sendo que no primeiro ciclo há superioridade do tratamento sem palhada apenas sobre o maior nível deste resíduo; não há uma tendência consistente para o acúmulo de nitrogênio para as folhas verdes e secas em função de diferentes aportes de palhada sobre o solo. Abstract: The aim of this study was to evaluate the contribution of different levels of straw on the accumulation of nitrogen in sugarcane. The trial was conducted at the harvests of 2011-12 and 2012-13 in Araras-SP, using the RB-845210 variety. There were tested five levels of straw (0% - 25% - 50% - 75% - 100%), related with 2,8 - 5,7 - 8,5 -11,3 t ha -1 ( 2011-12) and 3,0 ? 6,2 ? 9,4 ? 12,8 t ha -1 (2012-13), that were arranged in a randomized block design with four replications. To determine N accumulation in sugarcane there was used dry mass (kg ha -1 ) and N concentrations (g kg -1 ) of stalk, green and dry leaves, obtained by biometry evaluations realized during the two ratoons. Variance analyses and regressions were used as statistic tool. It is possible to conclude that after two cycles of sugarcane the inputs of 5-12 t ha -1 of straw by harvest has the same contribution for nitrogen stalk accumulation than traits without straw; although in the first cycle the trait without straw is superior than the higher level of this residue. About green and dry leaves there is no tendency for the nitrogen accumulation for the input of different levels of straw in soil

Flow boiling of R245fa in a single circular microchannel

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.The present paper describes an experimental setup for the investigation of two-phase heat transfer inside microchannels and reports local heat transfer coefficients measured during flow boiling of HFC-245fa in a 0.96 mm diameter single circular channel. The test runs have been performed during vapourization at around 1.85 bar, corresponding to 31 oC saturation temperature. As a peculiar characteristic of the present technique, the heat transfer coefficient is not measured by imposing the heat flux; instead, the boiling process is governedby controlling the inlet temperature of the heating secondary fluid. In the data, mass velocity ranges between 200 and 400 kg/m2s, with heat flux ranging between 5 and 85 kW/m2 and vapor quality from 0.05 up to 0.8. Since these data are not measured at uniform heat flux conditions, a proper analysis is performed to enlighten the influence of the different parameters and to compare the present data to those increasing the water-to-refrigerant temperature difference and by decreasing it. Finally, the experimental data are compared to models available in the literature for prediction of the heat transfer coefficients inside microchannels

Qualidade sanitária de grãos de amendoim submetidos a tratamentos com produtos naturais.

Resumo: Este trabalho teve por objetivo avaliar a ação do extrato de canela (Cinnamomum zeylanicum Blume) no controle de fungos de armazenamento de grãos de amendoim (Arachis hypogaea L.) em duas metodologias de aplicação (aplicação direta no papel germitest e imersão) e quatro tipos de tratamento (Testemunha, extrato aquoso de canela 5% no tempo zero, extrato aquoso de canela 5% preparado com 24 horas de antecedência, extrato etanólico 1%). Foi utilizada a técnica do Blotter test, por sete dias em fotoperíodo automático e temperatura de 25º C ± 1. O delineamento experimental foi o inteiramente casualizado (DIC) em esquema fatorial 2 x 2 x 4, sendo dois lotes, duas metodologias de aplicação e quatro tratamentos, com 20 repetições de 10 sementes, totalizando 200 sementes por tratamentos. Os resultados obtidos mostraram que, para Rhizopus stolonifer, o extrato etanólico de canela a 1% aplicado diretamente no papel Germitest apresentou o menor percentual de incidência fúngica. O tratamento de imersão não é indicado para o controle deste fungo. Para Penicillium spp e Aspergillus spp, o extrato aquoso de canela a 5% com os grãos de amendoim resulta em grãos com melhor qualidade sanitária. Uma concentração superior a 5% pode vir a conferir um maior percentual de inibição, podendo chegar à totalidade

Sobrevivência de patógenos em grãos de milho tratados com produtos naturais.

Resumo: Diante da propriedade inibitória da canela (Cinnamomum zeylanicum) para gêneros fúngicos, este trabalho teve por objetivo avaliar a ação da canela em diferentes formas e dois tipos de aplicação na sanidade de grãos de milho naturalmente infectados com Penicillium spp., Rhizopus sp., Fusarium spp. e Aspergillus spp. Utilizaram-se oito tratamentos com extratos de canela em duas concentrações, duas formas de aplicação em dois lotes comerciais de grãos de milho. Os tratamentos foram T1: Testemunha absoluta, T2: Extrato aquoso de canela 5% (T0h) aplicado diretamente no papel germitest, T3: Extrato aquoso de canela 5% (T24h) aplicado diretamente no papel germitest, T4: Extrato etanólico de canela 1% aplicado diretamente no papel germitest, T5: Testemunha-imersão, T6: Extrato aquoso de canela 5% (T0h)-imersão, T7: Extrato aquoso de canela 5% (T24h)-imersão, T8: Extrato etanólico de canela 1%-imersão. Os tratamentos que apresentaram melhores resultados para Penicillium spp. foram os que utilizaram os extratos aquosos de canela. O contato direto da canela em pó com o milho pode ocasionar a redução da incidência deste fungo em grãos armazenados. Para Fusarium spp., o extrato aquoso de canela a 5% aplicado em imersão reduziu em 52% incidência fúngica. O mesmo extrato em maiores concentrações poderá conferir um percentual maior de inibição, podendo alcançar a inibição total. Novos testes com número maior de lotes e concentrações do extrato são necessários para que os resultados sejam confirmados. Abstract: The aim of this work was to evaluate the effect of cinnamon extracts, at two technical of application on healthy of maize grains naturally infected with Penicillium spp., Rhizopus sp., Fusarium spp. and Aspergillus spp.. Eight treatments using two kinds of cinnamon extracts on two concentrations, two application types on two commercial maize lots. Treatments used were T1: witness (distilled water), T2: cinnamon aqueous extract 5% (T0h) applied directly on Germitest paper; T3: cinnamon aqueous extract 5% (T24h) applied directly on Germitest paper 24 hours after its prepare; T4: ethanolic cinnamon extract 1% applied directly on Germitest paper; T5: witness (distilled water - immersion), T6: cinnamon aqueous extract 5% (T0h) ? immersion; T7: cinnamon aqueous extract 5% (T24h) ? immersion; T8: ethanolic cinnamon extract 1% - immersion. Treatments that showed better results for Penicillium spp. were the aqueous cinnamon extracts. Direct contact of cinnamon powder with maize grains can reduce the incidence of this fungus on stored grains. For Fusarium spp., cinnamon aqueous extract 5% applied by immersion reduced the incidence of this fungus at 52%. The same extract, on higher concentrations can result a higher inhibition perceptual and can obtain total inhibition of Fusarium spp. on maize grains Another tests with higher number of lots and extracts concentrations are need to confirm these results

The radio emission pattern of air showers as measured with LOFAR - a tool for the reconstruction of the energy and the shower maximum

The pattern of the radio emission of air showers is finely sampled with the Low-Frequency ARray (LOFAR). A set of 382 measured air showers is used to test a fast, analytic parameterization of the distribution of pulse powers. Using this parameterization we are able to reconstruct the shower axis and give estimators for the energy of the air shower as well as the distance to the shower maximum.Comment: 15 pages, 10 figures, accepted for publication in JCA