Convex relaxation of mixture regression with efficient algorithms

We develop a convex relaxation of maximum a posteriori estimation of a mixture of regression models. Although our relaxation involves a semidefinite matrix variable, we reformulate the problem to eliminate the need for general semidefinite programming. In particular, we provide two reformulations that admit fast algorithms. The first is a max-min spectral reformulation exploiting quasi-Newton descent. The second is a min-min reformulation consisting of fast alternating steps of closed-form updates. We evaluate the methods against Expectation-Maximization in a real problem of motion segmentation from video data

O Projeto Político do Partido dos Trabalhadores em Cachoeiro de Itapemirim ES e a Gestão (2009 2012) no Âmbito dos Pilares do Modo Petista de Governar

A presente dissertação analisa a trajetória do Partido dos Trabalhadores no município de Cachoeiro de Itapemirim, cidade localizada ao sul do estado do Espírito Santo, e a chegada ao poder nas eleições de 2008, bem como a atuação da administração petista no período de 2009-2012, considerando a conjuntura política, econômica e social que se encontrava o cenário que é objeto do estudo. O levantamento do surgimento da cidade, seus aspectos naturais, econômicos, políticos, sociais e culturais são fatores importantes para a compreensão da história do tempo presente. A pesquisa também analisa o surgimento e a trajetória do Partido dos Trabalhadores no Brasil, no Espírito Santo, com ênfase em Cachoeiro de Itapemirim e a chegada ao poder no município. Entram na pauta da discussão ainda, as contradições do PT ao participar das eleições e afastar-se da sua base social. Com a chegada ao poder em Cachoeiro de Itapemirim-ES, município que apresenta muitas necessidades prioritárias, visivelmente no que concerne à infraestrutura urbana dos bairros periféricos, que cresceram desordenadamente e sem o acompanhamento do Poder Público, o governo petista se depara com o desafio de seguir as diretrizes do chamado Modo Petista de Governar, que tem como pilares a participação popular, a inversão de prioridadese a ética e a transparência no governo. A proposta é verificar se a administração petista, durante o primeiro mandato (2009-2012) seguiu os parâmetros indicados acima e os resultados dessas ações para a população, principalmente da periferia, que dependem mais das políticas públicas sociais. Palavras-chave: Partido dos Trabalhadores; Cachoeiro de Itapemirim; democracia; participação popular; Políticas públicas sociais

Conservation of Orbital Angular Momentum in Stimulated Down-Conversion

We report on an experiment demonstrating the conservation of orbital angular momentum in stimulated down-conversion. The orbital angular momentum is not transferred to the individual beams of the spontaneous down-conversion, but it is conserved when twin photons are taken individually. We observe the conservation law for an individual beam of the down-conversion through cavity-free stimulated emission.Comment: Submitted for publication in Phys. Rev. Let

Isolation and characterization of microsatellite loci from two inbreeding bark beetle species (Coccotrypes)

We developed 14 microsatellite markers in Coccotrypes carpophagus and 14 in C. dactyliperda. These loci will be used for studying genetic structure and the level of inbreeding in populations in the Canary Islands and Madeira. As a result of long-term inbreeding, genetic variability is relatively low in these bark beetle species. We found one to five alleles per locus in 29 C. carpophagus and 41 C. dactyliperda from various localities. Eleven of the markers developed for C. carpophagus amplified in C. dactyliperda and seven of the markers developed for C. dactyliperda amplified in C. carpophagus

Alginate-chitosan particulate delivery systems for mucosal immunization against tuberculosis

Although vaccination is still the most cost-effective strategy for tuberculosis control, there is an urgent need for an improved vaccine. Current BCG vaccine lacks efficacy in preventing adult pulmonary tuberculosis, the most prevalent form of the disease. Targeting nasal mucosa, Mycobacterium tuberculosis infection site, will allow a simpler, less prone to risk of infection and more effective immunization against disease. Due to its biodegradable, immunogenic and mucoadhesive properties, chitosan particulate delivery systems can act both as carrier and as adjuvant, improving the elicited immune response. In this study, BCG was encapsulated in alginate and chitosan microparticles, via a mild ionotropic gelation procedure with sodium tripolyphosphate as a counterion. The particulate system developed shows effective modulation of BCG surface physicochemical properties, suitable for mucosal immunization. Intracellular uptake was confirmed by effective transfection of human macrophage cell lines

Geomorphological frameworks in Portugal - a contribution for the characterzation of the geological heritage

Portugal presents a rich geodiversity in spite of its reduced area. Along 92 152 km2, the last 1000 Ma are recorded on different types of rocks. This lithological diversity together with major tectonic structures and specific Quaternary climatic conditions had developed several geomorphological features with high scientific, didactic, and aesthetic values. The concept of Geomorphological Heritage, part of what is considered Geological Heritage, has been developed by many authors during the last decade. The present work constitutes the first attempt for the definition of Portuguese geomorphological frameworks with national relevance, according to the objectives of the IAG's Geomorphological Sites Working Group and ProGEO. The emphasis is given to major landforms, with landscape value. Minor landforms and features shall be considered in the scope of a following detailed inventory and characterisation. The proposed frameworks cover all the Portuguese territory including Azores and Madeira archipelagos. For each framework some representative geosites were selected, based upon the spectacularity of the landforms, its rareness (in the Portuguese context), and essentially on its scientific and didactic values. The proposed frameworks include: i) granite landforms (Gerês and Estrela mountains); ii) carbonate and evaporite landforms (Aire and Candeeiros karsts); iii) volcanic landforms (Azores and Madeira Archipelagos); iv) residual landforms (Monsanto inselberg); v) tectonic landforms (Vilariça valley); vi) fluvial landforms as canyons (Douro) and alluvial plains (Lower Tejo); vii) coastal landforms like beaches (Quiaios-Aveiro), dunes (Porto Santo), lagoons (Obidos), estuaries (Tejo estuary), cliffs (Alentejo SW coast), and coastal platforms (Aveiro region); viii) glacial and periglacial landforms (cirques, glacial troughs, grooves, moraines and others in Estrela and Gerês mountains). Cultural landscapes are also considered, as the Alto Douro Wine Region and the Pico Island Vineyard Culture (respectively, inscribed and submitted to the World Heritage List). These examples are only indicative due to space restrictions. Until the present moment about sixty sites and areas with high geomorphological interest were considered. A significant number of those are included in protected areas, having therefore some kind of protection. Nevertheless, many others should be considered in geoconservation strategies to be implemented by Portuguese authorities

Evaluation of Y2O3 as front layer of ceramic crucibles for vaccum induction melting of tial based alloys

During the last decades titanium alloys were found to be valuable engineering materials for many different applications. Formerly used in critical applications like aerospace, aeronautic and military equipment, where the factor cost is not relevant, titanium alloys are finding now new and different markets. However, the development of such new markets will depend on an effective cost reduction of titanium parts, in order to achieve a selling cost suitable with its application in consumer goods. A possible solution to decrease production costs might be the use of traditional casting techniques to produce near net shape functional parts. During the last years, the authors have developed extensive research work on this field, and a new technique both for melting and moulding, using ceramic multi-layered crucibles and investment casting shells was developed. This paper presents some of the results obtained during that research work: Ti-48Al alloy were melted and cooled inside CaO, MgO and Y2O3 stabilized ZrO2 crucibles with inside layer of Y2O3. The chemical composition, hardness and microstructure at the metal-crucible interface, studied by secondary ion mass spectrometry, SEM/EDS and XRS are presented. On a second step, the same alloy was melted on the same crucibles, and poured into graphite moulds, and the crucibles wall was characterized by SEM/EDS and XRS.(undefined