Surface magnetization in non-doped ZnO nanostructures

We have investigated the magnetic properties of non-doped ZnO nanostructures by using {\it ab initio} total energy calculations. Contrary to many proposals that ferromagnetism in non-doped semiconductors should be induced by intrinsic point defects, we show that ferromagnetism in nanostructured materials should be mediated by extended defects such as surfaces and grain boundaries. This kind of defects create delocalized, spin polarized states that should be able to warrant long-range magnetic interactions.Comment: 8 pages, 3 figure

GEMINI: A Generic Multi-Modal Natural Interface Framework for Videogames

In recent years videogame companies have recognized the role of player engagement as a major factor in user experience and enjoyment. This encouraged a greater investment in new types of game controllers such as the WiiMote, Rock Band instruments and the Kinect. However, the native software of these controllers was not originally designed to be used in other game applications. This work addresses this issue by building a middleware framework, which maps body poses or voice commands to actions in any game. This not only warrants a more natural and customized user-experience but it also defines an interoperable virtual controller. In this version of the framework, body poses and voice commands are respectively recognized through the Kinect's built-in cameras and microphones. The acquired data is then translated into the native interaction scheme in real time using a lightweight method based on spatial restrictions. The system is also prepared to use Nintendo's Wiimote as an auxiliary and unobtrusive gamepad for physically or verbally impractical commands. System validation was performed by analyzing the performance of certain tasks and examining user reports. Both confirmed this approach as a practical and alluring alternative to the game's native interaction scheme. In sum, this framework provides a game-controlling tool that is totally customizable and very flexible, thus expanding the market of game consumers.Comment: WorldCIST'13 Internacional Conferenc

CH4 production at moderate H2/CO2 pressures insights on the use of anaerobic granular sludge as biocatalyst

Introduction: The continuous increase in energy consumption and the intensive use of fossil fuels, lead to the emission of greenhouse gases (GHG) and, in particular, to an increase in the concentration of CO2 in the atmosphere. In this context, the improvement in global awareness and the demand for sustainable technologies and products strongly contribute to laid plans to combat climate change. CO2-to-CH4 conversion represents a cutting-edge solution for CO2 capture and use, contributing to the reduction of GHG emission. Catalytic conversion of CO2-to-CH4 have been investigated, however, the high cost associated to the catalysts employed limits their use on a large scale. Biological CO2 methanation can overcome the significant technical and economic challenges of catalytic CO2 methanation. The biological production of CH4 using CO2-rich gases together with H2 is a promising strategy for the production of bioproducts. Hydrogenotrophic methanogens have a crucial role on the direct conversion of CO2+H2 into CH4, hence the importance to study the specific hydrogenotrophic methanogenic activity (SHMA). Methodology: In this work, the effect of initial substrate (H2/CO2) pressure, from 100 to 500 kPa, on the SHMA, on CH4 production rate and on developed microbial communities were evaluated. Two different pressurized bioreactors were studied using anaerobic granular sludge as the biocatalyst and H2/CO2 (80:20, v/v) as sole carbon and energy source. Gaseous compounds were analyzed by GC and archaeal diversity within granular sludge was monitored by 16S r-RNA based techniques. Results: The results showed an increase in the SHMA as well as in the CH4 production rate with the increase of the initial H2/CO2 pressure. This results are very interesting since no inhibitory effects were observed on the microbial activity, demonstrating the resistance of the anaerobic granular sludge. The Illumina results showed that Methanosarcinales, Methanobacteriales and Methanomicrobiales were the three orders that prevailed in the pressurized system, for all the pressures tested. However, hydrogenotrophic methanogens from Methanobacterium and Methanospirillum genera slightly increased their relative abundance, varying from 38% (100 kPa) to 41% (500 kPa) and from 8% (100 kPa) to 12% (500 kPa), respectively. Conclusions: In conclusion, the archaeal community seems to be very stable when submitted to increasing H2/CO2 pressures, highlighting the potential of the anaerobic granular sludge as an efficient microbial platform for the production of added-value compounds from gaseous carbon waste streams.Portuguese Foundation for Science and Technology (FCT): POCI-01-0145-FEDER-031377; strategic funding of UIDB/04469/2020 unit; BioTecNorte operation (NORTE-01-0145-FEDER-000004); FCT doctoral grant PD/BD/128030/2016.info:eu-repo/semantics/publishedVersio

CH4 production at moderate H2/CO2 pressures - insights on the specific hydrogenotrophic methanogenic activity

CO2 is one of the main contributors to greenhouse gases (GHGs), being its emission to the atmosphere one of the major driver of global climate change. Biological methanation of CO2 using renewable H2 provides a promising approach to use of superplus renewable electrical power to produce a gaseous fuel. CH4 is considered an important renewable energy carrier, that has a wide range of applications such as natural gas for distribution. Hydrogenotrophic methanogens are key elements in the CO2/H2 methanation process. Thus the importance to study the specific hydrogenotrophic methanogenic activity (SHMA). The effect of the initial substrate (H2/CO2) pressure on the SHMA was investigated in two different pressurized bioreactors. The results suggest that in addition to the increase of the initial substrate pressure, also the bioreactor configuration influence the SHMA, which is crucial for the success of biological CO2 methanation technologies but also in anaerobic bioreactors treating wastewaters.info:eu-repo/semantics/publishedVersio

Nesting in the lizard Phyllopezus pollicaris (Squamata: Phyllodactylidae) and a phylogenetic perspective on communal nesting in the family

Ninhadas comunais são encontradas em várias espécies de répteis. As hipóteses que explicam a evolução desse comportamento ainda são controversas, mas serão melhor compreendidas à medida que mais registros de ninhadas comunais forem descritos na literatura. Neste estudo, registramos duas ninhadas comunais de Phyllopezus pollicaris, incluindo a maior ninhada conhecida para a espécie. Este é o primeiro estudo a registrar ninhadas comunais para uma espécie de Squamata em uma região central do Cerrado. Além disso, também apresentamos fotografias das ninhadas, assim como medidas detalhadas e peso dos neonatos. As ninhadas foram encontradas durante a estação seca, em contraste com o padrão reprodutivo previamente descrito para a espécie na periferia do Cerrado. Nós também realizamos uma extensa revisão bibliográfica a respeito de ninhadas comunais na família Phyllodactylidae e apresentamos os resultados no contexto de uma árvore filogenética dos gêneros da família. Finalmente, sugerimos que estudar a correlação entre a evolução de ninhadas comunais e o investimento reprodutivo se tornará um campo de estudo fértil à medida que mais informações sobre ninhadas comunais estiverem disponíveis na literatura científica.Communal nesting occurs in many reptile species. The hypotheses that explain the evolution of such behaviours are still controversial, but will be better understood as more communal nesting records are described in the literature. We report the findings of two communal nests of Phyllopezus pollicaris, including the largest known nest for the species. Our study is the first to provide a communal nesting record for squamate species in a Cerrado core area. We provide nest photographs and detailed neonate measurements and weight. Nests were found during the dry season, in contrast with the reproduction pattern previously described for the species in the Cerrado periphery. We also conducted an extensive literature review seeking all available information on communal nesting information in Phyllodactylidae, and present this information in the context of a phylogenetic tree of phyllodactylid genera. We suggest that studying the correlation between communal nesting evolution and reproductive investment will become a fertile field as more information on lizard nesting becomes available in the literature

Eficiência de bio e imunoensaio para detecção de semente de soja geneticamente modificada tolerante ao glifosato em lotes de sementes de soja não transgênica.

A produção de semente de soja livre de sementes de outras cultivares ou outras sementes, dentro dos limites estabelecidos pela legislação, é facilitada pelo fato da soja ser espécie autógama. No caso específico das cultivares geneticamente modificadas (GM), a baixa taxa de fecundação cruzada que ainda pode existir é um dos pontos críticos de contaminação genética dos campos de sementes convencionais por transgênicos. O objetivo deste trabalho foi verificar a eficiência de dois métodos de detecção de misturas de semente GM em amostras de soja convencional, para avaliar lotes de sementes quanto aos limites exigidos pela legislação. Foram utilizadas amostras de semente da cultivar BRSMG 810C (convencional) e da cultivar BRSMG 850GRR. Foram avaliados dois tamanhos de amostras (200 e 400 sementes), com quatro níveis de contaminação (semente GM adicionada às amostras convencionais, para se obter 0%, 0,5%, 1% e 1,5%), e dois métodos de detecção: imunoensaio de fluxo lateral e bioensaio (pré-embebição em solução de herbicida a 0,6% do equivalente ácido, na proporção de 2,5 vezes o peso do substrato, por 16 horas no escuro a 25oC). O método de bioensaio é eficiente na detecção da presença de GM em amostras de semente convencional de soja, desde que as mesmas apresentem alta qualidade fisiológica. Existe correlação significativa entre os valores obtidos pelo método de detecção por bioensaio e os níveis de contaminação estabelecidos (r= 0,82; p< ou = 0,0001). O tamanho da amostra não influenciou a eficiência dos dois métodos na detecção da presença de sementes adventícias (GM)

Floating formulation for Bacillus thuringiensis var. israelensis obtained from semi-solid rice medium.

A loopful of Bti mantained on Luria-Bertani agar medium was transferred to Bacto-Peptona agar medium. After 3 days at 30oC, the petri-disheswere washed with sterilized water (100ml/petri-dish). The suspension obtained represented the inoculum for the semi-solid rice-based fermentation medium. The growth units were incubated until complete sporulation of Bti. The resulting biomass was dried at 60oC in an oven for 24h, sieved through 60 tyler. The retained powder did not show any larvicidal activity. In parallel, colloidal bentonite was treated with organic macromolecules dissolved in toluene, after sedimentation, the botton phase was dried at 120oC for 4h. This treatment led to a spreading and floating clay which resulted in a good carrier for Bti. Then, the the two powders were mixed in the proportion of 1(Bti):150(clay). The bioassays were performed under laboratory conditions utilizing 2nd instar Culex sp. larvae, with 3 repetitions (20 larvae each) being observed during 96 hours. The data were treated with Abbott method. A complete methodology was developed to get floating units of Bti with 143 mg/m2 of biological activity