Assessment of the food control systems in the Sultanate of Oman

National food control systems are vital tools in governing the safety and quality of food intended for human consumption. This study of the Omani system was conducted to evaluate the effectiveness of the current food controls in place for protecting, in particular, the public health from emerging biological and chemical hazards. In response to this situation, a survey was undertaken within the different food safety authorities in Oman to examine the different elements of the national food control systems in terms of their existing food control management, food legislation, food inspection, food analysis laboratories and information, education and communications. Officials from the different authorities were interviewed and results were captured in prepared questionnaires. Overall examinations of the challenges, strength and weakness of the existing system have been highlighted. The findings of the study indicate significant progress is being made and the creation by the government of a national Centre for Food Safety and Quality is a significant positive step.

A survey on wireless body area networks for eHealthcare systems in residential environments

The progress in wearable and implanted health monitoring technologies has strong potential to alter the future of healthcare services by enabling ubiquitous monitoring of patients. A typical health monitoring system consists of a network of wearable or implanted sensors that constantly monitor physiological parameters. Collected data are relayed using existing wireless communication protocols to the base station for additional processing. This article provides researchers with information to compare the existing low-power communication technologies that can potentially support the rapid development and deployment of WBAN systems, and mainly focuses on remote monitoring of elderly or chronically ill patients in residential environments.

Climatological features of cutoff low systems in the Southern Hemisphere

Cutoff lows (COLs) pressure systems climatology for the Southern Hemisphere (SH), between 10 degrees S and 50 degrees S, using the National Center for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) and the ERA-40 European Centre for Medium Range Weather Forecast (ECMWF) reanalyses are analyzed for the period 1979-1999. COLs were identified at three pressure levels (200, 300, and 500 hPa) using an objective method that considers the main physical characteristics of the conceptual model of COLs. Independently of the pressure level analyzed, the climatology from the ERA-40 reanalysis has more COLs systems than the NCEP-NCAR. However, both reanalyses present a large frequency of COLs at 300 hPa, followed by 500 and 200 hPa. The seasonality of COLs differs at each pressure level, but it is similar between the reanalyses. COLs are more frequent during summer, autumn, and winter at 200, 300, and 500 hPa, respectively. At these levels, they tend to occur around the continents, preferentially from southeastern Australia to New Zealand, the south of South America, and the south of Africa. To study the COLs at 200 and 300 hPa from a regional perspective, the SH was divided in three regions: Australia-New Zealand (60 E-130 W), South America (130 degrees W-20 degrees W), and southern Africa (20 degrees W-60 degrees E). The common COLs features in these sectors for both reanalyses are a short lifetime (similar to 80.0% and similar to 70.0% of COLs at 200 and 300 hPa, respectively, persisting for up to 3 days), mobility (similar to 70.0% and similar to 50% of COLs at 200 and 300 hPa, respectively, traveling distances of up to 1200 km), and an eastward propagation.

Comparison of Two Rotary Systems in Root Canal Preparation Regarding Disinfection

Introduction: The aim of the present study was to determine the disinfection of preparations carried out by using the Protaper or MTwo system in canals infected with Enterococcus faecalis. Methods: Twenty-eight distobuccal canals of upper molars were used, in which the canals were sterilized after being enlarged to #20 file and then contaminated with an inoculation of a culture of E. faecalis. After the incubation period, bacterial samples were collected and were seeded on plates for analysis of colony-forming units (CFU)/mL. The teeth were divided into 2 groups according to the rotary system used for instrumentation; 2 noninstrumented teeth served as the control group. Then bacterial samples were collected and were seeded on plates for analysis of CFU/mL again. The data obtained were evaluated by the Wilcoxon and Mann-Whitney U tests. Results: Bacterial reduction was 81.94% and 84.29%, respectively, in Pro Taper and Mtwo systems, and there was no statistically significant difference (P > .05). Conclusions: Both systems, Pro Taper and Mtwo, reduced the amount of bacteria in the mechanical disinfection of the root canal system, demonstrating that they are suitable for this purpose. (J Endod 2010;36:1238-1240)

PHA(MCL) biosynthesis systems in Pseudomonas aeruginosa and Pseudomonas putida strains show differences on monomer specificities

The production of PHA from plant oils by Pseudomonas species soil isolated from a sugarcane crop was evaluated. Out of 22 bacterial strains three were able to use efficiently plant oils to grow and to accumulate PHA. Pseudomonas putida and Pseudomonas aeruginosa strains produced PHA presenting differences on monomer composition compatible with variability on monomer specificity of their PHA biosynthesis system. The molar fraction of 3-hydroxydodecanoate detected in the PHA was linearly correlated to the oleic acid supplied. A non-linear relationship between the molar fractions of 3-hydroxy-6-dodecenoate (3HDd Delta(6)) detected in PHA and the linoleic acid supplied was observed, compatible with saturation in the biosynthesis system capability to channel intermediate of P-oxidation to PHA synthesis. Although P. putida showed a higher 3HDd Delta(6) yield from linoleic acid when compared to P. aeruginosa, in both species it was less than 10% of the maximum theoretical value. These results contribute to the knowledge about the biosynthesis of PHA with a controlled composition from plant oils allowing in the future establishing the production of these polyesters as tailor-made polymers. (C) 2009 Elsevier B.V. All rights reserved.

Thermodynamic Stabillity of Hydrogen-Bonded Systems in Polar and Nonpolar Environments

The thermodynamic properties of a selected set of benchmark hydrogen-bonded systems (acetic acid dimer and the complexes of acetic acid with acetamide and methanol) was studied with the goal of obtaining detailed information on solvent effects on the hydrogen-bonded interactions using water, chloroform, and n-heptane as representatives for a wide range in the dielectric constant. Solvent effects were investigated using both explicit and implicit solvation models. For the explicit description of the solvent, molecular dynamics and Monte Carlo simulations in the isothermal isobaric (NpT) ensemble combined with the free energy perturbation technique were performed to determine solvation free energies. Within the implicit solvation approach, the polarizable continuum model and the conductor-like screening model were applied. Combination of gas phase results with the results obtained from the different solvation models through an appropriate thermodynamic cycle allows estimation of complexation free energies, enthalpies, and the respective entropic contributions in solution. Owing to the strong solvation effects of water the cyclic acetic acid dimer is not stable in aqueous solution. In less polar solvents the double hydrogen bond structure of the acetic acid dimer remains stable. This finding is in agreement with previous theoretical and experimental results. A similar trend as for the acetic acid dimer is also observed for the acetamide complex. The methanol complex was found to be thermodynamically unstable in gas phase as well as in any of the three solvents. (C) 2010 Wiley Periodicals, Inc. J Comput Chem 31: 2046-2055, 2010

Bose systems in spatially random or time-varying potentials

Bose systems, subject to the action of external random potentials, are considered. For describing the system properties, under the action of spatially random potentials of arbitrary strength, the stochastic mean-field approximation is employed. When the strength of disorder increases, the extended Bose-Einstein condensate fragments into spatially disconnected regions, forming a granular condensate. Increasing the strength of disorder even more transforms the granular condensate into the normal glass. The influence of time-dependent external potentials is also discussed. Fastly varying temporal potentials, to some extent, imitate the action of spatially random potentials. In particular, strong time-alternating potential can induce the appearance of a nonequilibrium granular condensate.

On the efficiency of transportation systems in large cities

We report an analysis of the accessibility between different locations in big cities, which is illustrated with respect to London and Paris. The effects of the respective underground systems in facilitating more uniform access to diverse places are also quantified and investigated. It is shown that London and Paris have markedly different patterns of accessibility, as a consequence of the number of bridges and large parks of London, and that in both cases the respective underground systems imply in general, thought in distinct manners, an increase of accessibility. Copyright (C) EPLA, 2010

Birkhoffian Systems in Infinite Dimensional Manifolds

We generalize the theory of Kobayashi and Oliva (On the Birkhoff Approach to Classical Mechanics. Resenhas do Instituto de Matematica e Estatistica da Universidade de Sao Paulo, 2003) to infinite dimensional Banach manifolds with a view towards applications in partial differential equations.

Triphenylmethane dyes, an alternative for mediated electronic transfer systems in glucose oxidase biofuel cells

The bioelectrochemical behavior of three triphenylmethane (TPM) dyes commonly used as pH indicators, and their application in mediated electron transfer systems for glucose oxidase bioanodes in biofuel cells was investigated. Bromophenol Blue, Bromothymol Blue, Bromocresol Green were compared bio-electrochemically against two widely used mediators, benzoquinone and ferrocene carboxy aldehyde. Biochemical studies were performed in terms of enzymatic oxidation, enzyme affinity, catalytic efficiency and co-factor regeneration. The different features of the TPM dyes as mediators are determined by the characteristics in the oxidation/reduction processes studied electrochemically. The reversibility of the oxidation/reduction processes was also established through the dependence of the voltammetric peaks with the sweep rates. All three dyes showed good performances compared to the FA and BQ when evaluated in a half enzymatic fuel cell. Potentiodynamic and power response experiments showed maxima power densities of 32.8 mu W cm(-2) for ferrocene carboxy aldehyde followed by similar values obtained for TPM dyes around 30 mu W cm(-2) using glucose and mediator concentrations of 10 mmol L(-1) and 1.0 mmol L(-1), respectively. Since no mediator consumption was observed during the bioelectrochemical process, and also good redox re-cycled processes were achieved, the use of triphenylmethane dyes is considered to be promising compared to other mediated systems used with glucose oxiclase bioanodes and/or biofuel cells. (C) 2011 Elsevier Inc. All rights reserved.

Design method for solar heating systems in combination with pellet boilers/stoves

In this study an optimization method for the design of combined solar and pellet heating systems is presented and evaluated. The paper describes the steps of the method by applying it for an example of system. The objective of the optimization was to find the design parameters that give the lowest auxiliary energy (pellet fuel + auxiliary electricity) and carbon monoxide (CO) emissions for a system with a typical load, a single family house in Sweden. Weighting factors have been used for the auxiliary energy use and CO emissions to give a combined target function. Different weighting factors were tested. The results show that extreme weighting factors lead to their own minima. However, it was possible to find factors that ensure low values for both auxiliary energy and CO emissions.

Argumentative systems in robots

Nowadays, the development of intelligent agents intends to be more refined, using improved architectures and reasoning mechanisms. Revise the beliefs of an agent is also an important subject, due to the consistency that agents should have about their knowledge. In this work we propose deliberative and argumentative agents using Lego Mindstorms robots, Argumentative NXT BDI-like Agents. These agents are built using the notions of the BDI model and they are capable to reason using the DeLP formalism. They update their knowledge base with their perceptions and revise it when necessary. Two variations are presented: the Single Argumentative NXT BDI-like Agent and the MAS Argumentative NXT BDI-like Agent.

Population Fluctuations of Formicidae (Hymenoptera) and Araneae (Arachnida) in Two Tillage Systems in the Region of Guaíra-SP

The objective of this study was to elucidate population fluctuations of spider and ant species in forest fragments and adjacent soybean and corn crops under no-tillage and conventional tillage systems, and their correlations with meteorological factors. From Nov 2004 to Apr 2007 sampling of these arthropods at Guaira, São Paulo state was done biweekly during the cropping season and monthly during the periods between crops. To obtain samples at each experimental site, pitfall traps were distributed in 2 transects of 200 m of which 100 m was in the crop, and 100 m was in the forest fragment. Temperature and rainfall were found to have major impacts on fluctuations in population densities of ants of the genus, Pheidole, in soybean and corn crops both grown with conventional tillage and no tillage systems.

Spatial variability of soil physical properties in two management systems in sugarcane crop

O objetivo deste trabalho foi caracterizar a variabilidade espacial da densidade do solo (Ds), teor de água no solo (θ) e porosidade total (Pt) em dois sistemas de manejo da colheita da cana-de-açúcar, com queima e sem queima, em um Latossolo Vermelho, na camada de 0-0,20 m. A área de estudo está localizada no município de Rio Brilhante-MS, na Usina Eldorado. A parcela de cada talhão apresentou malha com comprimento de 180 m e largura de 145,6 m, perfazendo 90 pontos distribuídos na forma de uma grade de nove colunas por dez linhas, com pontos distanciados 20 m de seu vizinho. Foram coletadas amostras de solo na camada de 0-0,20 m, nos anos agrícolas de 2007/2008 e 2008/2009. O sistema de colheita com queima apresentou maior densidade em relação ao mecanizado, nos dois períodos de análise. O teor de água no solo, assim como a porosidade, teve aumento proporcional com relação à diminuição da densidade do sistema de colheita com queima para com o mecanizado.

Yield of upland rice cultivars in rainfed and sprinkler-irrigated systems in the Cerrado region of Brazil

In upland rice, the reduced grain yield that originates from the moisture stress period is related to the plant's tolerance of water deficiency and may vary between cultivars. The purpose of the work presented here was to evaluate the performance of upland rice cultivars in both rainfed and sprinkler-irrigated systems. A split-plot scheme with 8 replicates in a randomised block design was used. The plots were composed of 2 cropping systems (rainfed and sprinkler-irrigated) and the split-plot consisted of 2 cultivars (IAC 201 and Carajas) which are suggested for cultivation in upland ecosystems. Carajas had a greater number of panicles per square metre, higher spikelet fertility and grain mass, and, consequently, a higher grain yield than IAC 201 regardless of cropping system. IAC 201 was more sensitive to water deficiency than Carajas. Sprinkler irrigation improved spikelet fertility, grain mass and upland rice grain yield. Even when cultivars with a higher tolerance of water deficiency are used, a sprinkler-irrigated system may be a viable method to increase upland rice yield throughout most of the Brazilian Cerrado.