269 research outputs found

    New bounds for bb-Symbol Distances of Matrix Product Codes

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    Matrix product codes are generalizations of some well-known constructions of codes, such as Reed-Muller codes, [u+v,uāˆ’v][u+v,u-v]-construction, etc. Recently, a bound for the symbol-pair distance of a matrix product code was given in \cite{LEL}, and new families of MDS symbol-pair codes were constructed by using this bound. In this paper, we generalize this bound to the bb-symbol distance of a matrix product code and determine all minimum bb-symbol distances of Reed-Muller codes. We also give a bound for the minimum bb-symbol distance of codes obtained from the [u+v,uāˆ’v][u+v,u-v]-construction, and use this bound to construct some [2n,2nāˆ’2]q[2n,2n-2]_q-linear bb-symbol almost MDS codes with arbitrary length. All the minimum bb-symbol distances of [n,nāˆ’1]q[n,n-1]_q-linear codes and [n,nāˆ’2]q[n,n-2]_q-linear codes for 1ā‰¤bā‰¤n1\leq b\leq n are determined. Some examples are presented to illustrate these results

    An intelligent swarm based-wavelet neural network for affective mobile phone design

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    In this paper, an intelligent swarm based-wavelet neural network for affective mobile designed is presented. The contribution on this paper is to develop a new intelligent particle swarm optimization (iPSO), where a fuzzy logic system developed based on human knowledge is proposed to determine the inertia weight for the swarm movement of the PSO and the control parameter of a newly introduced cross-mutated operation. The proposed iPSO is used to optimize the parameters of wavelet neural network. An affective design of mobile phones is used to evaluate the effectiveness of the proposed iPSO. It has been found that significantly better results in a statistical sense can be obtained by the iPSO comparing with the existing hybrid PSO methods

    Performance stability and degradation mechanism of La0.6Sr0.4Co0.2Fe0.8O3-Ī“ cathodes under solid oxide fuel cells operation conditions

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    The performance stability and degradation mechanism of La0.6Sr0.4Co0.2Fe0.8O3d (LSCF)cathodes and LSCF impregnated Gd0.1Ce0.9O2d (LSCF-GDC) cathodes are investigated undersolid oxide fuel cell operation conditions. LSCF and LSCF-GDC cathodes show initiallyperformance improvement but degrade under cathodic polarization treatment at 750 C for120 h. The results confirm the grain growth and agglomeration of LSCF and in particularGDC-LSCF cathodes as well as the formation of SrCoOx particles on the surface of LSCFunder cathodic polarization conditions. The direct observation of SrCoOx formation hasbeen made possible on the surface of dense LSCF electrode plate on GDC electrolyte. Theformation of SrCoOx is most likely due to the interaction between the segregated Sr and Cofrom LSCF lattice under polarization conditions. The formation of SrCoOx would contributeto the deterioration of the electrocatalytic activity of the LSCF-based electrodes for the O2reduction in addition to the agglomeration and microstructure coarsenin

    Association between maternal pre-delivery body mass index and offspring overweight/obesity at 1 and 2 years of age among residents of a suburb in Taiwan

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    Background Overweight and obesity among children can cause metabolic syndrome in adulthood and are a significant public health issue. Some studies suggest that maternal pre-pregnancy body mass index (BMI) and excessive gestational weight gain during pregnancy are associated with overweight and obesity in offspring. However, it is difficult to collect information on accurate pre-pregnancy BMI and pregnancy weight gain for women living in areas where medical resources are scarce. Maternal pre-delivery BMI might be predictive of the risk of overweight and obesity among offspring of pregnant mothers living in suburban areas. Methods We retrospectively collected data on term neonates with appropriate weights for their gestational age born between April 2013 and October 2015. We excluded neonates with major congenital anomalies or diseases and incomplete data. Mothers with systemic diseases or drug abuse were also excluded. Offspring body weights and heights at 1- and 2-years-old were recorded. Maternal pre-delivery BMI was divided into following groups: <25, 25ā€“29.9, and ā‰§30 kg/m2. Results We included 261 mother-child pairs in this study. The BMIs of the offspring differed significantly among the three maternal pre-delivery BMI groups at the age of 2 years (15.18 Ā± 1.04, 15.83 Ā± 1.28, and 16.29 Ā± 1.61 kg/m2, p < 0.001, respectively). After adjusting for potential cofounders possibly affecting weight using multivariate linear regression, the childrenā€™s BMIs (adjusted 95% CI: 0.71 [0.31ā€“1.11]; p = 0.001) and BMI percentiles (adjusted 95% CI 15.80 [7.32ā€“24.28]; p < 0.001) at the age of 2 years were significantly higher in those born to mothers with pre-delivery BMIs of 25ā€“29.9 kg/m2 compared to mothers with pre-delivery BMIs <25 kg/m2. Maternal pre-delivery BMI ā‰§30 kg/m2 was significantly associated with increased BMIs (adjusted 95% CI: 1.17 [0.72ā€“1.63]; p < 0.001) and BMI percentiles (adjusted 95% CI: 23.48 [13.87ā€“33.09]; p < 0.001) in their children. A maternal pre-delivery BMI of 27.16 kg/m2 was the optimal cut-off for predicting offspring overweight/obesity at the age of 2 years. Discussion Our results indicate that the maternal pre-delivery BMI was significantly associated with offspring BMI and weight gain at the age of 2 years. A maternal pre-delivery BMI of 27.16 kg/m2 might be a useful predictor for estimating the risk of overweight or obesity in offspring at the age of 2 years

    Arsenic and Fluoride Exposure in Drinking Water: Childrenā€™s IQ and Growth in Shanyin County, Shanxi Province, China

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    BACKGROUND: Recently, in a cross-sectional study of 201 children in Araihazar, Bangladesh, exposure to arsenic (As) in drinking water has been shown to lower the scores on tests that measure childrenā€™s intellectual function before and after adjustment for sociodemographic features. OBJECTIVES: We investigated the effects of As and fluoride exposure on childrenā€™s intelligence and growth. METHODS: We report the results of a study of 720 children between 8 and 12 years of age in rural villages in Shanyin county, Shanxi province, China. The children were exposed to As at concentrations of 142 Ā± 106 Ī¼g/L (medium-As group) and 190 Ā± 183 Ī¼g/L (high-As group) in drinking water compared with the control group that was exposed to low concentrations of As (2 Ā± 3 Ī¼g/L) and low concentrations of fluoride (0.5 Ā± 0.2 mg/L). A study group of children exposed to high concentrations of fluoride (8.3 Ā± 1.9 mg/L) but low concentrations of As (3 Ā± 3 Ī¼g/L) was also included because of the common occurrence of elevated concentrations of fluoride in groundwater in our study area. A standardized IQ (intelligence quotient) test was modified for children in rural China and was based on the classic Ravenā€™s test used to determine the effects of these exposures on childrenā€™s intelligence. A standardized measurement procedure for weight, height, chest circumference, and lung capacity was used to determine the effects of these exposures on childrenā€™s growth. RESULTS: The mean IQ scores decreased from 105 Ā± 15 for the control group, to 101 Ā± 16 for the medium-As group (p < 0.05), and to 95 Ā± 17 for the high-As group (p < 0.01). The mean IQ score for the high-fluoride group was 101 Ā± 16 and significantly different from that of the control group (p < 0.05). Children in the control group were taller than those in the high-fluoride group (p < 0.05); weighed more than the those in the high-As group (p < 0.05); and had higher lung capacity than those in the medium-As group (p < 0.05). CONCLUSIONS: Childrenā€™s intelligence and growth can be affected by high concentrations of As or fluoride. The IQ scores of the children in the high-As group were the lowest among the four groups we investigated. It is more significant that high concentrations of As affect childrenā€™s intelligence. It indicates that arsenic exposure can affect childrenā€™s intelligence and growth

    Formulation of choline chloride/ascorbic acid natural deep eutectic solvent: Characterization, solubilization capacity and antioxidant property

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    In the present study, natural deep eutectic solvent composed of choline chloride and ascorbic acid (CHCL/AA NADES) was formulated for enhancing the solubility and antioxidant properties of antioxidant extracts from fruit wastes of Mangifera pajang. The solubilities of Mangifera pajang's antioxidant extracts in water and CHCL/AA NADES at different water contents (0ā€“50 wt%) were investigated. It was observed that the antioxidant extracts were most soluble in the CHCL/AA NADES with 10 wt% of water, and the concentration of antioxidant was found to be approximately 15% and 4% as compared to water and pure CHCL/AA NADES, respectively. The positive effect of water on NADES can be related to the reduced viscosity of NADES, where the viscosity decreased up to 74% upon addition of water. Aside from that, all the tested CHCL/AA NADES enhanced the antioxidant capacity of antioxidant extracts by 1.3ā€“14.64% compared to the antioxidant extracts in water. This finding highlights the role of CHCL/AA NADES as an antioxidant capacity enhancer. Noteworthy, the antioxidant extracts solubilized in the CHCL/AA NADES system formed a nano-scale cluster structure, as depicted by the TEM image, suggesting that the CHCL/AA NADES could potentially use in nanoformulation that provides protection to the antioxidant extracts
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