299 research outputs found
Optimal coincidence best approximation solution in non-Archimedean fuzzy metric spaces
In this paper, we introduce the concept of best proximal contraction theorems in non-Archimedean fuzzy metric space for two mappings and
prove some proximal theorems. As a consequence, it provides the existence of
an optimal approximate solution to some equations which contains no solution. The obtained results extend further the recently development proximal
contractions in non-Archimedean fuzzy metric spaces and famous Banach contraction principle.http://ijfs.usb.ac.iram2016Mathematics and Applied Mathematic
The sintering temperature effect on the shrinkage behavior of cobalt chromium alloy
Problem Statement: Co-Cr based alloys which is well known for its high Youngâs
modulus, fatigue strength, wear resistance and corrosion resistance is an important metallic bioïżœmaterial. However, till date there are only two type of Co-Cr alloy which are the castable and wrought
cobalt alloy. Powder Metallurgy route for cobalt is expected to give better result of Co-Cr alloy. The
purpose of this research was mainly to study the sintering temperature effect to the shrinkage
behavior of Cobalt Chromium (Co-Cr) alloy of the powder metallurgy route. Approach: Co-Cr was
produced following P/M route under sintering temperature of 1000, 1100, 1200, 1300 and 1400oC.
The sintering time was fixed at 60 min. Several tests has been conducted to determine this effect such
as the rate of shrinkage measurement, the bulk density and porosity percentage measurement,
compression and hardness tests and micro structural study. Result: From the study, it was found that
the sintering temperature has caused the shrinkage of Co-Cr. The increasing of the sintering
temperature has caused to the increasing of shrinkage of Co-Cr. This has resulted to the reduction of
the pore volume and hence increased it density. In conjunction to that, the strength and the hardness
of Co-Cr was increased. Conclusion: Therefore, it is hope that it will bring new view of powder
metallurgy Co-Cr alloy as bio-material
The sintering temperature effect on the shrinkage behavior of cobalt chromium alloy
Problem Statement: Co-Cr based alloys which is well known for its high Youngâs
modulus, fatigue strength, wear resistance and corrosion resistance is an important metallic bioïżœmaterial. However, till date there are only two type of Co-Cr alloy which are the castable and wrought
cobalt alloy. Powder Metallurgy route for cobalt is expected to give better result of Co-Cr alloy. The
purpose of this research was mainly to study the sintering temperature effect to the shrinkage
behavior of Cobalt Chromium (Co-Cr) alloy of the powder metallurgy route. Approach: Co-Cr was
produced following P/M route under sintering temperature of 1000, 1100, 1200, 1300 and 1400oC.
The sintering time was fixed at 60 min. Several tests has been conducted to determine this effect such
as the rate of shrinkage measurement, the bulk density and porosity percentage measurement,
compression and hardness tests and micro structural study. Result: From the study, it was found that
the sintering temperature has caused the shrinkage of Co-Cr. The increasing of the sintering
temperature has caused to the increasing of shrinkage of Co-Cr. This has resulted to the reduction of
the pore volume and hence increased it density. In conjunction to that, the strength and the hardness
of Co-Cr was increased. Conclusion: Therefore, it is hope that it will bring new view of powder
metallurgy Co-Cr alloy as bio-material
Synthesis, Biological Evaluation and Molecular Modeling Studies of Novel Chromone/Aza-Chromone Fused α-Aminophosphonates as Src Kinase Inhibitors
A series of novel chromone/aza-chromone fused α-aminophosphonate derivatives were synthesized in good yields using silica chloride as the catalyst. All the synthesized compounds were tested for their c-Src kinase inhibitory activity. Aza-chromone compound showed Src kinase inhibition with an IC50 value of 15.8 ”M. The compounds were subjected to molecular docking and dynamics simulations to study the atomic level interactions with an unphosphorylated proto-oncogenic tyrosine protein kinase Src (PDB code 1Y57) as well as phosphorylated tyrosine protein kinase Src (PDB code 2H8H). Docking and molecular dynamic results revealed phosphorylated Src tyrosine kinase protein better results than unphosphorylated tyrosine Src kinase protein. Chemoinformatics study revealed the compounds had lead like properties. Machine learning (SVR) models were built to study the structure activity correlations. A CC of 0.835 was obtained when the SVR model was applied to the 17 synthesized compounds. It is envisaged that the work will provide guidelines for future drug design efforts for Src kinase inhibitors
Distribution and cycling of terrigenous dissolved organic carbon in peatland-draining rivers and coastal waters of Sarawak, Borneo
South-East Asia is home to one of the world's largest stores of tropical
peatland and accounts for roughly 10 % of the global land-to-sea dissolved
organic carbon (DOC) flux. We present the first ever seasonally resolved
measurements of DOC concentration and chromophoric dissolved organic matter
(CDOM) spectra for six peatland-draining rivers and coastal waters in
Sarawak, north-western Borneo. The rivers differed substantially in DOC
concentration, ranging from 120â250 ”mol Lâ1 (Rajang River) to
3100â4400 ”mol Lâ1 (Maludam River). All rivers carried high
CDOM concentrations, with a350 in the four blackwater rivers between
70 and 210 mâ1 and 4 and 12 mâ1 in the other two rivers. DOC and CDOM
showed conservative mixing with seawater except in the largest river (the
Rajang), where DOC concentrations in the estuary were elevated, most likely
due to inputs from the extensive peatlands within the Rajang Delta. Seasonal
variation was moderate and inconsistent between rivers. However, during the
rainier north-east monsoon, all marine stations in the western part of our
study area had higher DOC concentrations and lower CDOM spectral slopes,
indicating a greater proportion of terrigenous DOM in coastal waters.
Photodegradation experiments revealed that riverine DOC and CDOM in Sarawak
are photolabile: up to 25 % of riverine DOC was lost within 5 days of
exposure to natural sunlight, and the spectral slopes of photo-bleached CDOM
resembled those of our marine samples. We conclude that coastal waters of
Sarawak receive large inputs of terrigenous DOC that is only minimally
altered during estuarine transport and that any biogeochemical processing
must therefore occur mostly at sea. It is likely that photodegradation plays
an important role in the degradation of terrigenous DOC in these
waters.</p
Associations of Neighborhood Crime and Safety and with Changes in Body Mass Index and Waist Circumference
Using data from the Multi-Ethnic Study of Atherosclerosis (MESA), we evaluated associations of neighborhood crime and safety with changes in adiposity (body mass index (BMI) and waist circumference). MESA is a longitudinal study of cardiovascular disease among adults aged 45-84 years at baseline in 2000-2002, from 6 US sites, with follow-up for MESA participants until 2012. Data for this study were limited to Chicago, Illinois, participants in the MESA Neighborhood Ancillary Study, for whom police-recorded crime data were available, and who had complete baseline data (n = 673). We estimated associations of individual-level safety, aggregated neighborhood-level safety, and police-recorded crime with baseline levels and trajectories of BMI and waist circumference over time using linear mixed modeling with random effects. We also estimated how changes in these factors related to changes in BMI and waist circumference using econometric fixed-effects models. At baseline, greater individual-level safety was associated with more adiposity. Increasing individual- and neighborhood-level safety over time were associated with decreasing BMI over the 10-year period, with a more pronounced effect observed in women for individual-level safety and men for neighborhood-level safety. Police-recorded crime was not associated with adiposity. Neighborhood-level safety likely influences adiposity change and subsequent cardiovascular risk in multiethnic populations
Assessing the psychometric and ecometric properties of neighborhood scales using adolescent survey data from urban and rural Scotland
This work was supported by NHS Health Scotland and the University of St Andrews.Background:Â Despite the well-established need for specific measurement instruments to examine the relationship between neighborhood conditions and adolescent well-being outcomes, few studies have developed scales to measure features of the neighborhoods in which adolescents reside. Moreover, measures of neighborhood features may be operationalised differently by adolescents living in different levels of urban/rurality. This has not been addressed in previous studies. The objectives of this study were to: 1) establish instruments to measure adolescent neighborhood features at both the individual and neighborhood level, 2) assess their psychometric and ecometric properties, 3) test for invariance by urban/rurality, and 4) generate neighborhood level scores for use in further analysis. Methods:Â Data were from the Scottish 2010 Health Behaviour in School-aged Children Survey, which included an over-sample of rural adolescents. The survey responses of interest came from questions designed to capture different facets of the local area in which each respondent resided. Intermediate data zones were used as proxies for neighborhoods. Internal consistency was evaluated by Cronbachâs alpha. Invariance was examined using confirmatory factor analysis. Multilevel models were used to estimate ecometric properties and generate neighborhood scores. Results:Â Two constructs labeled neighborhood social cohesion and neighborhood disorder were identified. Adjustment was made to the originally specified model to improve model fit and measures of invariance. At the individual level, reliability was .760 for social cohesion and .765 for disorder, and between .524 and .571 for both constructs at the neighborhood level. Individuals in rural areas experienced greater neighborhood social cohesion and lower levels of neighborhood disorder compared with those in urban areas. Conclusions:Â The scales are appropriate for measuring neighborhood characteristics experienced by adolescents across urban and rural Scotland, and can be used in future studies of neighborhoods and health. However, trade-offs between neighborhood sample size and reliability must be considered.Publisher PDFPeer reviewe
Association between heat stress and oxidative stress in poultry; mitochondrial dysfunction and dietary interventions with phytochemicals
Area-level deprivation and adiposity in children: is the relationship linear?
OBJECTIVE: It has been suggested that childhood obesity is inversely associated with deprivation, such that the prevalence is higher in more deprived groups. However, comparatively few studies actually use an area-level measure of deprivation, limiting the scope to assess trends in the association with obesity for this indicator. Furthermore, most assume a linear relationship. Therefore, the aim of this study was to investigate associations between area-level deprivation and three measures of adiposity in children: body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR). DESIGN: This is a cross-sectional study in which data were collected on three occasions a year apart (2005-2007). SUBJECTS: Data were available for 13,333 children, typically aged 11-12 years, from 37 schools and 542 lower super-output areas (LSOAs). MEASURES: Stature, mass and WC. Obesity was defined as a BMI and WC exceeding the 95th centile according to British reference data. WHtR exceeding 0.5 defined obesity. The Index of Multiple Deprivation affecting children (IDACI) was used to determine area-level deprivation. RESULTS: Considerable differences in the prevalence of obesity exist between the three different measures. However, for all measures of adiposity the highest probability of being classified as obese is in the middle of the IDACI range. This relationship is more marked in girls, such that the probability of being obese for girls living in areas at the two extremes of deprivation is around half that at the peak, occurring in the middle. CONCLUSION: These data confirm the high prevalence of obesity in children and suggest that the relationship between obesity and residential area-level deprivation is not linear. This is contrary to the 'deprivation theory' and questions the current understanding and interpretation of the relationship between obesity and deprivation in children. These results could help make informed decisions at the local level
Relation between Neighborhood Environments and Obesity in the MESA
This study investigated associations between neighborhood physical and social environments and body mass index in 2,865 participants of the Multi-Ethnic Study of Atherosclerosis (MESA) aged 45â84 years and residing in Maryland, New York, and North Carolina. Neighborhood (census tract) environments were measured in non-MESA participants residing in MESA neighborhoods (2000â2002). The neighborhood physical environment score combined measures of a better walking environment and greater availability of healthy foods. The neighborhood social environment score combined measures of greater aesthetic quality, safety, and social cohesion and less violent crime. Marginal maximum likelihood was used to estimate associations between neighborhood environments and body mass index (kg/m2) before and after adjustment for individual-level covariates. MESA residents of neighborhoods with better physical environments had lower body mass index (mean difference per standard deviation higher neighborhood measure = â2.38 (95% confidence interval (CI): â3.38, â1.38) kg/m2 for women and â1.20 (95% CI: â1.84, â0.57) kg/m2 for men), independent of age, race/ethnicity, education, and income. Attenuation of these associations after adjustment for diet and physical activity suggests a mediating role of these behaviors. In men, the mean body mass index was higher in areas with better social environments (mean difference = 0.52 (95% CI: 0.07, 0.97) kg/m2). Improvement in the neighborhood physical environment should be considered for its contribution to reducing obesity.http://deepblue.lib.umich.edu/bitstream/2027.42/60334/1/Relation between Neighborhood Environments and Obesity in the Multiethnic Study of Atherosclerosis.pd
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