Random-energy model in random fields

The random-energy model is studied in the presence of random fields. The problem is solved exactly both in the microcanonical ensemble, without recourse to the replica method, and in the canonical ensemble using the replica formalism. The phase diagrams for bimodal and Gaussian random fields are investigated in detail. In contrast to the Gaussian case, the bimodal random field may lead to a tricritical point and a first-order transition. An interesting feature of the phase diagram is the possibility of a first-order transition from paramagnetic to mixed phase.Comment: 18 pages, 5 figures (included

Net cage tambaqui farming: microbiological quality, nutritional value and yield.

Tambaqui is traditionally consumed at a commercial size of 1.0 to 3.0 kg However, it is also consumed at between 0.350 to 0.450 kg, this size being referred to as tambaqui curumim (C). The objective of this study was to evaluate the microbiological quality of tambaqui at the commercial size (CS) and to characterize the nutritional value and yield of tambaqui belonging to the two size classes Curumim and CS originating from net cages. The effect of size on the centesimal composition and fish yield was evaluated in a completely randomized design with 12 repetitions while for the microbiological analysis one fish from each net cage was used. C showed protein, ash and moisture contents above those of CS, whereas the ether extract was higher for CS. The yields were 70.04% for C and 65.55% for CS. 50% of the samples showed contamination by Staphylococcus aureus, all values being within the Brazilian?s regulation limits. Salmonella spp. was found in 91.67% of the samples while 75% showed contamination by total coliforms and 8.34% by Escherichia coli. C showed a suitable nutritional value and a better yield in relation to CS. The addition of C to the diet will depend on its acceptance in the markets where its commercialization is not yet established. The microbiological results suggest a tendency of the species to harbor Salmonella spp. on the body surface

Globular clusters in the inner Galaxy classified from dynamical orbital criteria

Globular clusters (GCs) are the most ancient stellar systems in the Milky Way. Therefore, they play a key role in the understanding of the early chemical and dynamical evolution of our Galaxy. Around 40 per cent of them are placed within ∼4 kpc from the Galactic centre. In that region, all Galactic components overlap, making their disentanglement a challenging task. With GaiaData Release 2, we have accurate absolute proper motions for the entire sample of known GCs that have been associated with the bulge/bar region. Combining them with distances, from RR Lyrae when available, as well as radial velocities from spectroscopy, we can perform an orbital analysis of the sample, employing a steady Galactic potential with a bar. We applied a clustering algorithm to the orbital parameters apogalactic distance and the maximum vertical excursion from the plane, in order to identify the clusters that have high probability to belong to the bulge/bar, thick disc, inner halo, or outer halo component. We found that ∼30 per cent of the clusters classified as bulge GCs based on their location are just passing by the inner Galaxy, they appear to belong to the inner halo or thick disc component, instead. Most GCs that are confirmed to be bulge GCs are not following the bar structure and are older than the epoch of the bar formation

Clavulanic acid and cephamicin c: a perspective of the biosynthesis, isolation and action mechanism

The present article reviews different aspects of the chemistry of two widely used β-lactam antibiotics Clavulanic Acid and Cephamycin C. The article discusses important details of the biosynthesis of these compounds, their action mechanism and, principally, the methods employed in their isolation and purification, in accordance with the available literature. Despite the large quantity of available articles and patents concerning β-lactam antibiotics, those which describe the isolation and purification of Clavulanic Acid and Cephamycin C are rare. Overall, the intention of this article is to discuss the up-to-date scientific research related to the compounds under review.FAPESPCNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Chondrocranium and internal oral morphology of the tadpole of Corythomantis greeningi (Anura: Hylidae)

Corythomantis greeningi é uma perereca-de-cabeça-ossificada que ocorre em regiões xéricas e sub-úmidas do nordeste do Brasil. Frequentemente os indivíduos são encontrados sobre as rochas às margens de riachos temporários ou em acúmulos de água nos “lajedos”. Girinos suctoriais muitas vezes são encontrados aderidos às rochas dos riachos para não serem carreados pelas correntes e por isso, apresentam morfologia externa e interna muito particulares. Aqui, descrevemos a anatomia oral interna e o condrocrânio do girino de C. greeningi e comparamos com as descrições disponíveis de representantes da subfamília Lophyohylinae e outros girinos suctoriais. A morfologia oral interna em C. greeningi assemelha-se aos girinos dos demais sapos de cabeça ossificada que se desenvolvem em poça, apesar deste ter sido encontrado em ambiente temporário lótico. Corythomantis greeningi tem uma morfologia condrocranial particular em relação aos outros Lophyohylinae descritos, apresentando marcadas diferenças nos cornua trabeculae e palatoquadrate. Aparentemente, a morfologia do condrocrânio está mais relacionada a aspectos ecomorfológicos, pois é estruturalmente mais semelhante a outros girinos suctoriais que habitam ambientes lóticos do que com espécies filogeneticamente mais próximas, como Trachycephalus typhonius and Phyllodytes gyrinaethesCorythomantis greeningi is a casque-headed frog that occurs in xeric and sub-humid regions of northeastern Brazil. Individuals are often found on rocks on banks of temporary streams or in ponds upon “lajedos”. Suctorial tadpoles are often found clasping to the rocks in the streams so as not to be dragged by the current; therefore, they have modified external and internal morphology. Here, we describe the internal oral anatomy and the chondrocranium of the tadpole of C. greeningi and compare it to the available descriptions of Lophyohylinae and other suctorial tadpoles. The internal oral morphology in C. greeningi resembles pond-dwelling casque-headed frogs, although it has been found in temporary lotic environments. Corythomantis greeningi has unusual chondrocranial morphology relative to that of other described Lophyohylinae, including marked differences at the cornua trabeculae and palatoquadrate. Apparently, the chondrocranial morphology is related to its ecomorphology, because it is structurally more similar to other suctorial tadpoles that inhabit lotic environments than to phylogenetically related species such as Trachycephalus typhonius and Phyllodytes gyrinaethe

Larval chondrocranial and internal oral morphology of the neotropical treefrog Boana crepitans (Wied-Neuwied, 1824; Amphibia, Anura, Hylidae)

We describe the internal oral morphology and chondrocranial anatomy for Boana crepitans tadpoles, and compare them with available descriptions for other species in the subfamily Cophomantinae. Among species of the Boana faber group, the chondrocranial anatomy has been reported only for one species internal oral morphology and cranial anatomy are similar to other described species of Boana and Cophomantinae. B. crepitans lacks unique features in the oral cavity and chondrocranium that would distinguish it from other congeneric species. We identify six characters from the internal oral anatomy of tadpoles unique for Cophomantinae. In addition, Boana has infralabial papillae projections, buccal floor arena papillae, and lateral ridge papillae projections shorter than those described for Aplastodiscus and Bokermannohyla

Quantification and source identification of atmospheric particulate polycyclic aromatic hydrocarbons and their dry deposition fluxes at three sites in Salvador Basin, Brazil, impacted by mobile and stationary sources

The present work has aimed to determine the 16 US EPA priority PAH atmospheric particulate matter levels present in three sites around Salvador, Bahia: (i) Lapa bus station, strongly impacted by heavy-duty diesel vehicles; (ii) Aratu harbor, impacted by an intense movement of goods, and (iii) Bananeira village on Maré Island, a non vehicle-influenced site with activities such as handcraft work and fisheries. Results indicated that BbF (0.130-6.85 ng m-3) is the PAH with highest concentration in samples from Aratu harbor and Bananeira and CRY (0.075-6.85 ng m-3) presented higher concentrations at Lapa station. PAH sources from studied sites were mainly of anthropogenic origin such as gasoline-fueled light-duty vehicles and diesel-fueled heavy-duty vehicles, discharges in the port, diesel burning from ships, dust ressuspension, indoor soot from cooking, and coal and wood combustion for energy production.O presente trabalho apresenta o estudo sobre 16 HPAs prioritários em material particulado atmosférico de três sítios próximos a Salvador-BA: (i) Estação da Lapa, estação de ônibus da Região Metropolitana de Salvador; (ii) Porto de Aratu, impactado por intenso movimento de matérias-primas e (iii) Bananeira, localizado na Ilha de Maré, vilarejo que tem como principais atividades a pesca e artesanato. Resultados mostraram que o BbF (0,130-6,85 ng m-3) foi o HPA com as concentrações mais elevadas em Aratu e Bananeira e CRY (0,075-6,85 ng m-3) apresentou nível mais elevado na Lapa. As fontes de HPAs nos sítios estudados foram principalmente de origem antrópica, tais como veículos de pequeno e grande portes, carregamentos do porto, ressuspensão de partículas do solo, queima de diesel das embarcações e a queima de carvão e madeira para produção de energia.CNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)FINEPFAPESBPRONEXRECOMBIONordeste GenerationANEELFAPES

Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia

In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001–December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance

Rapid determination of flavonoids and phenolic acids in grape juices and wines by RP-HPLC/DAD: Method validation and characterization of commercial products of the new Brazilian varieties of grape.

A method for rapid determination of phenolic compounds by reversed-phase high-performance liquid chromatography (RP-HPLC), using a new column of faster resolution was validated and used to characterize commercial products produced with new grape Brazilian varieties of Northeast of Brazil. The in vitro antioxidant activity was also measured. The method showed linearity (R > 0.9995), good precision (CV% < 2.78), recovery (91.8?105.1%) and limits of detection (0.04?0.85 mg L-1 ) and quantification (0.04?1.41 mg L-1 ) according to other methods previously published with the difference of a run time of only 25 min. The results obtained in the characterization of the samples differed for juices and wines from other world regions, mainly because of the high values of (-)-epigallocatechin and trans-caftaric acid. The products analyzed showed high antioxidant activity, especially the wine samples with values higher than those from wines of different regions of the worl