Room Temperature Organic Superconductor?

The electron--phonon coupling in fullerene C28 has been calculated from first principles. The value of the associated coupling constant lambda/N(0) is found to be a factor three larger than that associated with C60. Assuming similar values of the density of levels at the Fermi surface N(0) and of the Coulomb pseudopotential for C28-based solids as those associated with alkali-doped fullerides A3C60, one obtains Tc(C28) \approx 8 Tc(C60).Comment: 10 pages, 2 figure

Mapping the stranger: genetic diversity of Manila clam in European coastal lagoons.

Manila clam Ruditapes philippinarum - synonym Venerupis philippinarum (Adams and Reeve, 1850) is one of the most successful marine invaders worldwide and represents almost 20% of worldwide mollusc total production. Originally distributed in the Indo-Pacific region, the species was introduced for aquaculture and fisheries in North America, Polynesia, the US Virgin Islands, as well as in Atlantic and Mediterranean coasts of Europe. Due to the commercial value of the species, population genetics and stock composition are of primary importance both in natural and invaded environments. Moreover, molecular genetics can provide valuable data in invasion biology, as, for example, the structure of the exploited populations, the origin of source populations and the routes of invasions. Furthermore, molecular data might be useful for the tracking of seafood products, as requested by the European Commission for European seafood products (see EC laws n° 178/2002, 509/2006, 510/2006 and their improvements). Despite all these considerations genetic data are lacking, especially for introduced populations, and should be urgently provided. In a framework of an European network of researchers involved in Manila clam studies, clams were collected in coastal lagoons and estuaries in both Mediterranean (Northern Adriatic Sea, Italy) and Atlantic (Spain and Portugal) coasts of Europe. Both mitochondrial and nuclear molecular markers were applied to investigate the genetic structure of populations, specifically by the direct sequencing of 16S rDNA gene fragments and by the genotyping of 7 microsatellite markers previously used in native populations. Results demonstrated the occurrence of multiple haplotypes for 16S rDNA, even if one main haplotype was identified in the European analyzed populations. However, few sequences were available in Genbank to make comparisons with native populations. Concerning the microsatellite data, the genotyping of Manila clam populations showed low genetic diversity among them, considering the Fst values, and a lack of genetic structuring when analysed by Structure software. Both these data suggest the absence of geographic differentiation among the introduced populations of Manila clam, as a result of introgression due to translocations and other human activities. The levels of genetic diversity within introduced populations were comparable to those described from native regions, suggesting that multiple introduction events and mixed source populations can counterbalance the loss of genetic diversity caused by the founder effect. However, it must be remarked that microsatellites showed a strong occurrence of null alleles when tested by Micro-checker, as previously observed in other bivalves, suggesting that the problem is differently distributed among Manila clam populations or specific loci, thus microsatellites should be carefully checked before used in extensive population studies. In the near future, population genetics and stock identification of this species on a large scale should be assessed using new powerful markers such as those obtained by NGS (Next Generation Sequencing) methods. In conclusion, this research represents the very first extensive genetic investigation on Manila clam’s European populations, defining the levels of genetic diversity that will help to inform management practices

Electron-Phonon Coupling in Charged Buckminsterfullerene

A simple, yet accurate solution of the electron-phonon coupling problem in C_{60} is presented. The basic idea behind it is to be found in the parametrization of the ground state electronic density of the system calculated making use of ab-initio methods, in term of sp$^{2+x}$ hybridized orbitals. This parametrization allows for an economic determination of the deformation potential associated with the fullerene's normal modes. The resulting electron-phonon coupling constants are used to calculate Jahn-Teller effects in C_{60}^-, and multiple satellite peaks in the corresponding photoemission reaction. Theory provides an accurate account of the experimental findings.Comment: 11 pages, 3 figures. Accepted for publication in Chem. Phys. Let

Influência de cultivares de feijão-caupi no crescimento populacional de Callosobruchus maculatus (FABR., 1775) (Coleoptera: Chrysomelidae: Bruchinae).

Na região Nordeste do Brasil a cultura do feijão-caupi tem grande importância socioeconômica, exercendo função no suprimento das necessidades nutricionais e fixação de mão-de-obra. Dentre as pragas que atacam os grãos de feijão-caupi durante o armazenamento, destaca-se Callosobruchus maculatus, por provocar perdas quantitativas e qualitativas. O controle deste inseto é feito principalmente com inseticidas sintéticos, no entanto, com os problemas decorrentes da intoxicação de aplicadores e seleção de insetos resistentes, formas alternativas de controle têm sido buscadas. Neste contexto, o objetivo deste trabalho foi avaliar a influência de cultivares de caupi no crescimento populacional de C. maculatus. Para realização do experimento utilizou-se cultivares de caupi provenientes da Embrapa Semiárido: BRS Guariba, BRS Maratoã, BRS Milênio, BRS Paraguaçu e BRS Pujante, além da testemunha Sempre Verde. Realizou-se teste sem chance de escolha, avaliando-se número de insetos emergidos e a taxa instantânea de crescimento populacional. A cultivar BRS Pujante apresentou os melhores resultados em relação aos parâmetros biológicos testados, apresentando possivelmente resistência do tipo antibiose.CONAC 2012. Disponível em: http://www.conac2012.org/resumos/pdf/241a.pdf. Acesso em: 08 ago. 2013

Volatilização de amônia proveniente de uréia com zeólita natural.

O objetivo deste trabalho foi avaliar os efeitos da adição de zeólita a grânulos de ureia e dos diâmetros de grânulos nas perdas de NH3 por volatilização e na absorção de N pelo sorgo. Formulações de ureia com adição de zeólita e ligante orgânico, nos diâmetros menores que 2 mm, 2-4 mm e maiores que 4 mm e, sulfato de amônio e ureia-NBPT, foram aplicados à superfície do solo sobre bandejas, em casa de vegetação. A adição de zeólitas naturais à superfície dos grânulos de ureia ou à composição destes diminuiu as perdas por volatilização em 20% e aumentou a extração de N pelas plantas. A acumulação de N nas plantas de sorgo foi inversamente proporcional às perdas de N por volatilização

Breakthrough pain in oncology: a longitudinal study.

Abstract CONTEXT: Existing studies on breakthrough pain (BP) have reported different prevalence rates because of different settings, populations, and assessment methods. These studies have used cross-sectional designs, and the relationship of BP with analgesic treatment has not been evaluated. OBJECTIVES: The aim of this study was to longitudinally assess BP in cancer patients admitted to oncology units. METHODS: A consecutive sample of patients admitted to oncology centers was selected. At admission (T0), three months after admission (T3), and six months after admission (T6), data on background pain and BP were recorded. BP was assessed in terms of its intensity, duration, number of episodes, onset with movement, spontaneous relief after stopping activity, limitation of physical activity, and effectiveness of analgesics. RESULTS: Three hundred two patients completed the study. At T0, T3, and T6, 39%, 38%, and 33% patients, respectively, had continuous pain (P=0.294). Pain intensity significantly decreased (P=0.004 and 0.027 at T3 and T6, respectively). Most patients had BP at T0 (87.1%), T3 (80.9%), and T6 (73.2%), and there was a significant decrease in the prevalence of BP over time (P=0.016). Of 149 patients with BP, pain on movement was recorded in 43.6%, 43.4%, and 32.4% at T0, T3, and T6, respectively (P=0.228). Pain spontaneously decreased or ceased when stopping physical activity in 66%, 56%, and 62% at T0, T3, and T6, respectively (P=0.537). Pain on movement strongly limited physical activity in most patients. CONCLUSION: These data expand current information about BP and underline the need for a longitudinal assessment of a phenomenon that is invariably dependent on stage of disease, patient, and therapeutic factors

Volatilização de amônia proveniente de ureia com zeólita natural.

O objetivo deste trabalho foi avaliar os efeitos da adição de zeólita a grânulos de ureia e dos diâmetros de grânulos nas perdas de NH3 por volatilização e na absorção de N pelo sorgo. Formulações de ureia com adição de zeólita e ligante orgânico, nos diâmetros menores que 2 mm, 2?4 mm e maiores que 4 mm e, sulfato de amônio e ureia‑NBPT, foram aplicados à superfície do solo sobre bandejas, em casa de vegetação. A adição de zeólitas naturais à superfície dos grânulos de ureia ou à composição destes diminuiu as perdas por volatilização em 20% e aumentou a extração de N pelas plantas. A acumulação de N nas plantas de sorgo foi inversamente proporcional às perdas de N por volatilização

3D microfabricated scaffolds and microfluidic devices for ocular surface replacement: a review

In recent years, there has been increased research interest in generating corneal substitutes, either for use in the clinic or as in vitro corneal models. The advancement of 3D microfabrication technologies has allowed the reconstruction of the native microarchitecture that controls epithelial cell adhesion, migration and differentiation. In addition, such technology has allowed the inclusion of a dynamic fluid flow that better mimics the physiology of the native cornea. We review the latest innovative products in development in this field, from 3D microfabricated hydrogels to microfluidic devices