Use of terrain evaluation techniques in the study of drainage network changes in microbasins of the Capivari River Basin, state of São Paulo, Brazil

In this paper the drainage network is considered as a geo-indicator of the environmental changes that haven taken place over a period of 23 years in three hydrographic microbasins in the São Paulo State (Brazil). The verification of the natural conditions of the physical environment was based on terrain evaluation for homogeneity of landforms and the materials associated with them. In order to identify the alterations, a temporal analysis of the drainage network morphometric variables and land use was made. The morphometric analysis indicates a decrease in the number of first-order channels and in the total length of all channels, with a consequential modification of the drainage and hydrographic densities. The losses and gains of the first-order channels were influenced by the slope, type of bedrock and presence of unconsolidated material. The catalyst for these changes was mainly the inadequate control of urban expansion and the intensive agricultural activities.Résumé Dans cet article le réseau de drainage est considéré comme un géo-indicateur de changements environnementaux qui se sont réalisés durant 23 années dans trois micro-bassins hydrographiques de létat de Sao Paulo (Brésil). Les caractéristiques du milieu physique ont été obtenues à partir dune étude des différentes unités géomorphologiques et des formations géologiques corrélatives. Afin de mettre en évidence les modifications du milieu, une analyse temporelle de loccupation des sols et des paramètres morphométriques du réseau de drainage a été réalisée. Lanalyse morphométrique indique une diminution du nombre de sections de premier ordre et de la longueur totale du réseau de drainage. Il en résulte une modification de la densité de drainage des bassins. Les diminutions ou augmentations de sections de premier ordre ont été influencées par la pente, le type de substratum et la présence de matériaux meubles. Une expansion urbaine mal contrôlée et le développement dune agriculture intensive sont les causes de ces modifications.     

VNF-Consensus: A virtual network function for maintaining a consistent distributed software-defined network control plane

Software-defined networks (SDN) usually rely on a centralized controller, which has limited availability and scalability by definition. Although a solution is to employ a distributed control plane, the main issue with this approach is how to maintain the consistency among multiple controllers. Consistency should be achieved with as low impact on network performance as possible and should be transparent for controllers, without requiring any change of the SDN protocols. In this work, we propose VNF-Consensus, a virtual network function that implements Paxos to ensure strong consistency among controllers of a distributed control plane. In our solution, controllers can perform their control plane activities without having to execute the expensive tasks required to keep consistency. Experimental results are presented showing the cost and benefits of the proposed solution, in particular in terms of low controller overhead.     

Effects of High-Pressure Processing on the Quality of Sea Bass (Dicentrarchus labrax) Fillets During Refrigerated Storage

The aim of this study was to evaluate the effect of high-pressure processing (HPP) on the quality of fresh sea bass fillets using two pressure levels (250 and 400 MPa; 5 min pressure holding time). Vacuum-packed fillets were used as control samples, and all fillets were stored under refrigerated conditions for 18 days. The microbiological, chemical, physical, and sensory parameters were followed. Both HPP treatments increased the microbiological shelf life of sea bass fillets. In day 14, control samples reached the upper acceptability limit (7 log colony-forming units (CFU)?g^?1), while fillets treated at 250 and 400 MPa had 3.2 and 1.4 log CFU g^?1, respectively. In general, hydrogen sulphide-producing bacteria and Enterobacteriaceae loads were below the detection limit in HPP treatments. Results from nucleotide analysis indicate that HPP treatments reduced the conversion of inosine 5′-monophosphate to inosine. HPP also influenced fillet sensory characteristics. The most evident changes in fillets were the increase in whiteness, the loss of translucency, and a firmer consistency. The effect was more pronounced in the treatment at 400 MPa. Lipid oxidation increased in HPP-treated samples, being more accentuated in the treatment at 400 MPa. Instrumental smell intensity increased in both HPP treatments, though the sensory panel did not detect any rancid or other unpleasant odours. No effect was observed in the amount of volatile bases or in pH values. In conclusion, HPP treatments showed potential application for new fish product development with increased microbiological safety and shelf life, longer freshness, and unique characteristics (e.g. firmer and whitish).     

Identification of (-)(E)-N-[2(S)-Hydroxy-2-(4-hydroxyphenyl) ethyl]ferulamide, a natural product isolated from Croton pullei: theoretical and experimental analysis

Ferulic acid (FA) and its derivatives (FADs) are known for a variety of biological activities, such as photo-protective agent, antioxidant, antiatherogenic and antiplasmodial activities. During structural definition of a FAD isolated from Croton pullei, the possibility of a heterologous series made this definition difficult. In this regard, computational simulations were performed using theoretical calculations at DFT level to predict Infrared (IR) and Nuclear Magnetic Resonance (NMR) data. The IR and NMR (13)C and (1)H data were compared with the theoretical calculations performed for three structural possibilities of a heterologous series. The theoretical results were compared with the experimental data through linear regression in order to define the most probable structure and showed satisfactory values.     

Effects of the addition of mechanically deboned poultry meat and collagen fibers on quality characteristics of frankfurter-type sausages

The effects of mechanically deboned poultry meat (MDPM) and levels of collagen fibers on comminuted, cooked sausage quality characteristics were investigated using the central composite rotatable design of response surface methodology (RSM). Use of collagen fiber as an additive affected the sausage characteristics, but the effect depended on the amount of the MDPM used. While MDPM additions resulted in higher cooking loss and darker and redder frankfurters, the addition of collagen fibers improved cooking yields and contributed to the lightness of the final product. Higher collagen fiber content was also accompanied by a significant increase in frankfurter hardness regardless of the MDPM content. Use of collagen fibers countered the negative effects of MDPM on sausage quality attributes, especially on cooking yields and final product color.     

Factors affecting slab surface roughness of siliceous dimension stones

The sawing of granite blocks using multi-blade gangsaws and an abrasive mixture is one of the most complex operations in the rock transformation industry. The surface quality of the finished slabs is the main determinant of the volume of material to be removed in subsequent polishing operations, thus affecting the product’s final cost. Measurements carried out on five types of siliceous dimension stone slabs showed differences in sawing speed and industrial process costs. The roughness values obtained, together with the test results for the uniaxial compressive strength, Amsler wear, sawability, coefficient of dynamic friction and petrographic analysis, showed that the rock texture has the most important influence on the production cost of polished slabs.     

Protein changes after irradiation and ice storage of horse mackerel (Trachurus trachurus)

Anthocyanin-rich concentrates from different fruits can be used as natural food colourants. The pigments' stability is comparatively low and dependent on the composition of food matrices. Food ingredients relevant for soft drinks, jelly fruits and salad dressings were tested in model systems regarding their influence on the colour stability of elderberry and black currant concentrate determined by colour measurement (CIE L ^* a ^* b ^*). In aqueous solutions food-grade organic acids and salt were found to influence anthocyanin stability: colour stability increased with increasing pK _a of acids and decreased with increasing salt concentrations. This may be attributed to altered solvation characteristics of aqueous solutions. A stabilizing influence was found for sugars presumably by reducing water activity. However, when heat treatment was applied, e.g. in the production of hydrocolloid gels, fructose was shown to accelerate anthocyanin decay due to the formation of sugar degradation products. Comparing hydrocolloids, alginate was shown to increase colour stability in aqueous solution and pectin displayed overall highest colour stability in a gel model system, suggesting that polyuronic acids may improve anthocyanin stability by intermolecular association.