Optical properties of P3HT and N2200 polymers: a performance study of an optimally tuned DFT functional

The optical properties of systems composed of the polymers PolyeraActivInk? N2200 and P3HT are experimentally and theoretically investigated using UV-Vis spectroscopy and time-dependent density functional theory calculations, respectively. From a theoretical point of view, we carried out an analysis considering several functionals and model oligomers of different sizes to mimic the polymers. As our studies were performed with and without solvents, a first important result regards the fact that, by considering solvent effects, a better agreement between theoretical and experimental results could be achieved. Our findings also show that an optimally tuned functional is better suited to describe the experimental absorption profile than a hybrid one for the flexible polymer (P3HT). For the almost rigid polymer considered here (N2200), on the other hand, hybrid functionals may perform better than tuned functionals.     

ERRγ Preserves Brown Fat Innate Thermogenic Activity

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Differentially expressed proteins associated with drought tolerance in bananas (<Emphasis Type="Italic">Musa</Emphasis> spp.)

Bananas are one of the most important fruits in tropical and subtropical regions worldwide. Each year, banana plantations expand, but the areas available are mostly dry lands. The establishment of strategies for obtaining drought tolerant cultivars depends on understanding of biological responses at genetic, molecular and biochemical levels. Proteomics is a powerful tool for functional characterization of the response of plants to abiotic stress and little is known about drought tolerance in Musa spp. Therefore, the aim of this study was to identify proteins related to drought tolerance in two contrasting banana genotypes, Prata Anã and BRS Tropical, susceptible and tolerant to drought, respectively. Proteins were extracted from rhizomes of bananas grown under greenhouse conditions with control, irrigated and water deficit regimes. The differential protein expression pattern was established by two-dimensional (2-D) electrophoresis and spots analyzed in nano Q-Tof Micro UPLC. Twenty-three differentially expressed proteins were found in the tolerant genotype (BRS Tropical) under water deficit, with proteins involved in metabolism, defense and transport. Proteins were classified according to known function and biosynthetic pathways. Signaling proteins in response to water stress, especially for the biological function of growth and development of plants cells, were also encountered, whereas heat shock proteins played a significant role. This is the first report of proteomic analysis for drought tolerance in ‘Pome’ and ‘Silk-type’ bananas containing the ‘B’ genome. Our work provides insights into Musa spp. response to drought and data for further studies regarding molecular mechanisms, which determine how Musa spp. cells better overcome environmental perturbations.     

Cleaning by the wrasse Thalassoma noronhanum, with two records of predation by its grouper client Cephalopholis fulva

The Noronha wrasse Thalassoma noronhanum was recorded cleaning 19 client fish species at Fernando de Noronha Archipelago, o. north–eastern Brazil. The preferred clients were non–dangerous, mostly planktivorous species, whereas the potentially dangerous, predatory species were rarely cleaned. T. noronhanum acts as a cleaner in two distinct ecological situations, at and outside the cleaning stations, and attends different client species in each of them. Potentially dangerous clients were mostly attended outside the cleaning stations. Many attacks and two instances of predation on the cleaner wrasse by the grouper client Cephalopholis fulva were recorded. The attacks occurred on individual wrasses foraging near the bottom outside the cleaning stations.     

Performance of the DNA-Citoliq liquid-based cytology system compared with conventional smears

OBJECTIVE: To evaluate the performance of a new, manual, simplified liquid-based system, DNA-Citoliq (Digene Brasil), employed under routine conditions as compared to conventional smears collected from six collaborating private laboratories. METHODS: A panel of cytopathologists, who served as the gold standard diagnosis, adjudicated discordant opinions. RESULTS: Of 3206 pairs of slides considered valid for comparison, there were 3008 in full agreement (93.8%), 112 (3.5%) with one diagnostic category discrepancies, and 86 (2.7%) discordant cases. Among the 288 borderline+ by either method, DNA-Citoliq detected abnormalities in 243 (84.4%), and conventional smears (CS) detected abnormalities in 178 (61.8%) (McNemar test, P < 0.000), a 36.5% increased detection of borderline+ cases. CONCLUSIONS: For mild dyskaryosis, DNA-Citoliq detected 176 cases and CS 125 cases (McNemar test, P < 0.000); and for moderate+severe dyskaryosis 66 versus 32 cases respectively (McNemar test, P < 0.000).     

Susceptibility of the Coffee Leaf Miner (Perileucoptera spp.) to Bacillus thuringiensisδ-Endotoxins: A Model for Transgenic Perennial Crops Resistant to Endocarpic Insects

Binding of several Bacillus thuringiensisδ-endotoxins was studied on histological midgut sections of larvae of coffee leaf miner Perileucoptera coffeella from Brazil and Perileucoptera sp from Madagascar. CryIA(a), CryIA(b), CryIA(c), CryIB, CryIE, and CryIIA were tested for binding, and only CryIA(c), CryIB, and CryIE yielded a positive response. The toxins bound to the whole midgut, and the result was identical on both insect populations. The same toxins, to the number of which CryIC was added, were tested on larvae of P. coffeella. CryIA(c) and CryIB were toxic with an LC50 of 1.47 μg/ml and 21.93 μg/ml, respectively. CryIE was not toxic to P. coffeella. CryIA(c) and CryIB were tested for synergistic activity and were shown to act by cumulative effect when delivered to the insect larvae as a mixture. Received: 30 July 1997 / Accepted: 26 August 1997     

Human introduction or natural dispersion? Atlantic Ocean occurrence of the Indo‐Pacific whitetip reef shark Triaenodon obesus

Occurrence of multiple whitetip reef sharks Triaenodon obesus in the Atlantic Ocean is reported for the first time from near a sunken ferry off the Paraná coast in south‐eastern Brazil. This occurrence is hypothesized to have been caused by either a human introduction or a remarkably long oceanic displacement.     

Diversification by host switching and dispersal shaped the diversity and distribution of avian malaria parasites in Amazonia

Understanding how pathogens and parasites diversify through time and space is fundamental to predicting emerging infectious diseases. Here, we use biogeographic, coevolutionary and phylogenetic analyses to describe the origin, diversity, and distribution of avian malaria parasites in the most diverse avifauna on Earth. We first performed phylogenetic analyses using the mitochondrial cytochrome b (cyt b) gene to determine relationships among parasite lineages. Then, we estimated divergence times and reconstructed ancestral areas to uncover how landscape evolution has shaped the diversification of Parahaemoproteus and Plasmodium in Amazonia. Finally, we assessed the coevolutionary patterns of diversification in this host–parasite system to determine how coevolution may have influenced the contemporary diversity of avian malaria parasites and their distribution among Amazonian birds. Biogeographic analysis of 324 haemosporidian parasite lineages recovered from 4178 individual birds provided strong evidence that these parasites readily disperse across major Amazonian rivers and this has occurred with increasing frequency over the last five million years. We also recovered many duplication events within areas of endemism in Amazonia. Cophylogenetic analyses of these blood parasites and their avian hosts support a diversification history dominated by host switching. The ability of avian malaria parasites to disperse geographically and shift among avian hosts has played a major role in their radiation and has shaped the current distribution and diversity of these parasites across Amazonia.