Variability for oil and fatty acid composition in castorbean varieties

Thirty-six castorbean varieties were surveyed for oil and fatty acid composition, in order to determine variability of these seed compounds. A large variability of seed oil percentage was observed, ranging from 39.6 to 59.5%. Concerning the fatty acids, little variability was observed for ricinoleic acid, which was the most abundant in the oil, ranging from 83.65 to 90.00%. The other fatty acids appeared in small concentrations and showed a small range: 0.87 to 2.35, 0.68 to 1.84, 2.96 to 5.64, 3.19 to 5.98, and 0.34 to 0.91%, for palmitic, stearic, oleic, linoleic, and linolenic acid, respectively. Non-significant correlations were observed between fatty acids and seed oil percentage. However, significant correlations were observed among fatty acid concentrations: positive and negative ones. These significant correlations could be associated with the biosynthetic pathways of the fatty acids, which are not fully elucidated. They suggest, however, that selection for a particular fatty acid will tend to increase those positively correlated, and decrease those negative ones. Selection and plant breeding techniques could then be applied to modify the oil content of the castorbean seeds, considering the variability observed. For the fatty acid composition, however, the variability was not large enough to make substantial changes in their concentrations by selection procedures. More varieties should be surveyed to find out if such variability is available.     

Stereoscopy and Scanning Electron Microscopy of Brazil Nut (Bertholletia excelsa H.B.K.) Shell,Brown Skin,and Edible Part: Part One—Healthy Nut

In this article, tissue layers and cells characteristics of the Brazil nut (Bertholletia excelsa H.B.K.) shell (tegument), brown skin (testae), and edible part (cotyledons) were identified by stereoscopy (SM) and scanning electron microscopies (SEM). (a) The shell (a lignin rich, protective wall) varies in thickness throughout the nut structure and comprises different tissue types (total 3)/texture (hard/mid‐hard/soft), layers (2 to 5), colors (light to dark brown and white to cream), cell shape (amorphous/flattened on both surfaces; polygonal and cylindrical with thick, porous primary and secondary wall in cross‐section), and vascular distribution (helically and polyedrical thickened vessels at soft tissue and locule/channel structures). These variations are observed either in the shell faces, face corners, nut tips, or locule in testae. (b) The brown skin (shell nut part linked to both the shell and edible part) is made of flattened irregular‐shaped parenchymal cells distributed in several layers with more flexible fibrous, thinner wall tissue than shell. It has both rough and smooth shiny texture on the upper and lower surfaces, respectively. However, the nut (c) edible part, that is the nut storage tissue, shows several different tissue/cell layers starting from epidermis (double/triple cells sequence of round and palisade shapes) layer–the endosperm tissue. The parenchymal tissues show cells of irregular shape with small and larger sizes distributed in regular and randomly layers, respectively, separated by a short meristem tissue layer. The cortex cells increase in size as they approach the cotyledons junction. The Brazil nut part's tissue layers and cells were identified by the SM and SEM microscopy methods applied, which provides knowledge for further understanding of nut alterations that may occur either in the forest or during the factory processing.     

Multistage Shared-Per-Wavelength Optical Packet Switch: Heuristic Scheduling Algorithm and Performance

This paper describes an optical switch architecture based on the shared-per-wavelength strategy for contention resolution in the wavelength domain. This strategy impacts on wavelength converters requirements and switch organization, by allowing to obtain cost saving. The general sharing concept is first introduced and the related practical solution as a multistage switch architecture is presented and thoroughly analyzed in terms of performance, control and cost perspectives. Heuristic scheduling to manage packet forwarding in a synchronous context is developed and discussed in terms of computational complexity. A simple accurate analytical model is developed and validated against simulation to numerically evaluate packet loss performance of the shared-per-wavelength switch. The main achievement of the work is represented by the proposal of a feasible approach which leads to remarkable cost saving in terms of optical gates and wavelength converters under the conditions outlined.     

Antifungal properties of Zinc‐compounds against toxigenic fungi and mycotoxin

Antifungal and antimycotoxin properties of zinc (Zn) compounds were evaluated against toxigenic strains of Fusarium graminearum, Penicillium citrinum and Aspergillus flavus. In addition, was verified the activity of these Zn‐compounds on conidia production, hyphae morphological alterations, mortality and reactive oxygen species (ROS) production. The Zn‐compounds treatments utilised were zinc oxide nanoparticles (ZnO‐NPs), zinc oxide (ZnO), zinc sulphate (ZnSO₄) and zinc perchlorate (Zn(ClO₄)₂). The Zn‐compounds effect on growth diameter of fungal colony was concentration dependent. Two treatments (ZnSO₄ and Zn(ClO₄)₂) completely inhibited the fungal growth and their ability to produce mycotoxins. The conidia production of all fungi also was reduced after the treatment with Zn‐compounds. Morphological alterations occurred in the treated fungi showing hyphae damage. The treatments led to cell death and ROS production observed in the fungi hyphae. ZnSO₄ and Zn(ClO₄)₂ were the compounds that showed better results as antifungal, presenting antimycotoxin activity and caused alterations in the fungi cell structure.     

A multimodal hand-based verification system with an aliveness-detection module

This paper presents a multimodal biometrie verification system based on the following hand features: palmprint, four digitprints and four fingerprints. The features are obtained using the Karhunen-Loève transform based approach, and information fusion at the matching-score level was applied. We experimented with different resolutions of the regions of interest, different numbers of features and several normalization and fusion techniques at the matching-score level. To increase the reliability of the system to spoof attacks we included an aliveness-detection module based on thermal images of the hand dor sa. The verification performance when using a system configuration with optimum parameters, i.e., resolution, number of features, normalization and fusion technique, showed an equal error rate (EER) of 0.0020%, which makes the system appropriate for the implementation of high-security biometric systems.     

Microstructural and electrical changes in nickel manganite powder induced by mechanical activation

Nickel manganite powder synthesized by calcination of a stoichiometric mixture of manganese and nickel oxide was additionally mechanically activated in a high energy planetary ball mill for 5-60 min in order to obtain a pure NiMn₂O₄ phase. The as-prepared powders were uniaxially pressed into disc shape pellets and then sintered for 60 min at 1200 °C. Changes in the particle morphology induced by mechanical activation were monitored using scanning electron microscopy, while changes in powder structural characteristics were followed using X-ray powder diffraction. The ac impedance spectroscopy was performed on sintered nickel manganite samples at 25 °C, 50 °C and 80 °C. It was shown that mechanical activation intensifies transport processes causing a decrease in the average crystallites size, while longer activation times can lead to the formation of aggregates, defects and increase of lattice microstrains. The observed changes in microstructures were correlated with measured electrical properties in order to define optimal processing conditions.     

A study of the photocatalytic degradation of metamitron in ZnO water suspensions

The photocatalytic degradation of the herbicide metamitron in water using ZnO under Osram ULTRA-VITALUX® lamp light was studied. The effect of the operational parameters such as initial concentration of catalyst, initial metamitron concentration, initial salt concentration (NaCl, Na₂CO₃ and Na₂SO₄) and pH was studied. The optimal concentration of catalyst was found to be 2.0 g/l. First-order rate constants were calculated for the uncatalysed reactions. On the base of the Langmuir-Hinshelwood mechanism, a pseudo first-order kinetic model was illustrated and the adsorption equilibrium constant and the rate constant of the surface reaction were calculated (0.119 l mg^− 1 and 0.836 mg l^− 1 min^− 1, respectively). The photodegradation rate was higher in acidic than in alkaline conditions. When salt effect was studied, it was found that sodium carbonate was the most powerful inhibitor used, while sodium chloride was the weakest one. A negligible inhibition was observed when the concentration of sodium chloride was 20 mM.The rate of photodecomposition of metamitron was measured using UV spectroscopy and HPLC, while its mineralization was followed using ion chromatography (IC), as well as total organic carbon (TOC) and total nitrogen (TN) analysis.Under the employed conditions, almost complete disappearance of 9 mg/ml of herbicide, 56% TOC and 34% TN removal, occurred within 4 h. The ion chromatography results showed that the mineralization led to ammonium, nitrite and nitrate ions during the process.     

Automatic calibration of urban drainage model using a novel multi-objective genetic algorithm.

In order to successfully calibrate an urban drainage model, multiple calibration criteria should be considered. This raises the issue of adopting a method for comparing different solutions (parameter sets) according to a set of objectives. Amongst the global optimization techniques that have blossomed in recent years, Multi Objective Genetic Algorithms (MOGA) have proved effective in numerous engineering applications, including sewer network modelling. Most of the techniques rely on the condition of Pareto efficiency to compare different solutions. However, as the number of criteria increases, the ratio of Pareto optimal to feasible solutions increases as well. The pitfalls are twofold: the efficiency of the genetic algorithm search worsens and decision makers are presented with an overwhelming number of equally optimal solutions. This paper proposes a new MOGA, the Preference Ordering Genetic Algorithm, which alleviates the drawbacks of conventional Pareto-based methods. The efficacy of the algorithm is demonstrated on the calibration of a physically-based, distributed sewer network model and the results are compared with those obtained by NSGA-II, a widely used MOGA.     

Multifiber Shared-Per-Wavelength All-Optical Switching: Architectures, Control, and Performance

A new wavelength converter sharing strategy for multifiber optical switches, namely shared-per-wavelength (SPW), which employs wavelength converters with fixed input wavelengths is presented. The aim is to reduce switch costs by using simpler optical components and low complexity space switching matrices. Practical implementations of both the well-known shared-per-node (SPN) and the new SPW schemes are presented, as well as the related scheduling algorithms to manage optical packet forwarding in synchronous scenario. An analytical model to evaluate blocking performance of the SPN architecture is also provided. Results show the accuracy of the model in the range of interest for switch design. The proposed architectures are compared in terms of performance and number of optical components employed. The SPW approach is shown to save a large number of semiconductor optical amplifier gates with respect to the SPN one when the number of fibers per interface is suitably not too high. In these cases, the SPW architecture requires a number of wavelength converters higher than the SPN, but simpler, being their inputs tuned on a single wavelength.     

Characterization of P2x1 purinoreceptors on rat platelets: effect of clopidogrel

This study aimed to determine the binding characteristics of [3H]alpha,beta-Me-ATP, a specific ligand of the P2x1 receptors to rat platelets, and to investigate the effect of clopidogrel, a thienopyridine compound which has been found to selectively inhibit ADP-induced platelet aggregation and adenylyl cyclase ex vivo. Binding of [3H]alpha,beta-Me-ATP to rat platelets was time-dependent and saturable. Scatchard analysis of the saturation binding data indicated that [3H]alpha,beta-Me-ATP bound to one population of specific binding sites with high affinity (KD = 23.6 +/- 1.6 nM; Bmax = 690 +/- 24 fmole/10[8]cells) (n=3). Unlabelled alpha,beta-Me-ATP as well as 2-MeS-ADP and ADP competitively inhibited the specific binding of [3H]alpha,beta-Me-ATP with IC50 values of 19.0 +/- 6.6, 103 +/- 20 and 1120 +/- 80 nM respectively (n=3). Other nucleotide analogues such as ATP, ATP-gammaS, UTP and GTP also antagonized [3H]alpha,beta-Me-ATP binding. When administered orally (10mg/kg, p.o.), clopidogrel inhibited ADP- or 2-MeS-ADP-induced platelet aggregation but did not affect the binding of [3H]alpha,beta-Me-ATP to rat platelets ex vivo. In vitro, alpha,beta-Me-ATP did not induce the aggregation or shape change of rat platelets and did not interfere with ADP-induced platelet aggregation.