Modeling of carbon dioxide fixation by microalgae using hybrid artificial intelligence (AI) and fuzzy logic (FL) methods and optimization by genetic algorithm (GA)

Environmental Science and Pollution Research - In this study, we are reporting a novel prediction model for forecasting the carbon dioxide (CO2) fixation of microalgae which is based on the hybrid...     

Factor analysis and linear regression model (LRM) of metal speciation and physico-chemical characters of groundwater samples

An approach is described for viewing the interrelationship between different variables and also tracing the sources of pollution of groundwater of north Chennai (India). The data set of 43 variables which include major ions, minor ions and trace metal speciation (Cu, Pb, Cd and Zn) collected during the pre-monsoon and post-monsoon seasons of the year 2000–2001, was subjected to R-mode factor analysis to comprehend the distribution pattern of the said variables. It was found that first factor measures salinity and hardness which explained 19.12% of the total variance (comprised of variables EC, TDS, Na⁺, K⁺, Ca²⁺, Mg²⁺, total hardness, Cl⁻ and SO₄ ²⁻) during pre-monsoon, while it was 25.08% during post-monsoon. The second and third factors were attributed to speciation of zinc and copper ions during both pre-monsoon and post-monsoon. Although there were two more factors, loaded with speciation parameters of lead and cadmium, the variance of them were less than 10%. From this study it is seen that sea water intrusion, municipal solid waste disposal are the identified sources of component of pollution. The importance of metal ions is taking a secondary role and the anthropogenic origin-industrial activity, is the reason in the evaluation of pollution status as they come in the second, third, fourth and fifth factors. As the trace metal speciation was grouped in separate factors, linear regression model (LRM) with correlation analysis was applied to check its validity for prediction of speciation and to apply LRM for rapid monitoring of water pollution.     

Review: Biomechanics of Child Occupant Protection

This paper provides a review on the following issues: the differences in injury patterns between adults and children under similar loading conditions during an automotive crash event. Because of the recent awareness and the ensuing necessity, as an example, injuries including fatalities due to airbag deployment are discussed. Biomechanical differences explain the varying injury patterns and mechanisms of injury. The commonly adopted scaling techniques for predicting pediatric tolerances are described. A comparison of the biomechanical properties of the pediatric and adult structures is given. Some insight is provided with regard to the use of these data to develop validated mathematical models of pediatric structures. The paper concludes with recommendations for further research.     

Neuroprotective potential of N -acetylcysteine in carbofuran neurotoxicity: A biochemical and histopathological study

The present study was undertaken to evaluate biochemical markers of chronic carbofuran exposure to rats in terms of lipid peroxide and intrasynaptosomal calcium levels and to correlate them with the histopathological changes in brain regions. A significant increase in lipid peroxidation (LPO) in terms of thiobarbituric acid reactive substances (TBARS) was observed in the cerebral cortex (65%) and brain stem (33%) after carbofuran exposure. This was accompanied by a significant increase (87%) in the intracellular free-Ca²⁺ [Ca²⁺]_i levels. N-acetylcysteine (NAC) administration, on the other hand, reversed the carbofuran-induced increase in LPO and [Ca²⁺]_i. Histopathological studies of carbofuran-exposed brain revealed high frequency of pyknotic neurons in the cerebral cortex and microhaemorrhages in the brain stem. NAC supplementation to carbofuran-treated animals resulted in normalisation of the brain architecture as seen by a reduction in the number of pyknotic nuclei in the cerebral cortex. These findings indicate that increased LPO and elevated [Ca²⁺]_i levels are involved in the development of carbofuran neurotoxicity and are eventually responsible for the pathological alterations. The study also demonstrates potential neuroprotective effect of NAC treatment in carbofuran neurotoxicity.     

Biomechanics of Pediatric Cervical Spine: Compression,Flexion and Extension Responses

The objective of the present study was to develop three separate age-specific one, three, and six year old pediatric human cervical spine (C4-CS-C6) three-dimensional nonlinear finite element models and to quantify the biomechanical responses. The adult model was modified to create one, three, and six year old pediatric spines by incorporating the local geometrical and material characteristics of the developmental anatomy. The adult human cervical spine model was constructed from close-up computed tomography sections and sequential anatomic cryomicrotome sections, and validated with experimental data. The biomechanical responses were compared with the adult human cervical spine behavior under different loading modes using three approaches. Approach 1: using pure overall structural scaling (reduce size) of the adult model. Approach 2: using three separate age-specific pediatric models incorporating local component geometrical and material property changes. Approach 3: applying the overall structural scaling to the above three pediatric models. All pediatric structures were consistently more flexible than the adult spine under all loading modes. However, responses obtained using the pure overall structural scaling (Approach 1) increased the flexibilities slightly. In contrast, the inclusion of local component geometrical and material property changes to create the three individual pediatric cervical spine models (Approach 2) produced significantly higher changes in the flexibilities under all loading modes. When overall structural scaling effects were added to the three pediatric models (Approach 3), the increase was not considerably higher. White the one year old pediatric model was the most flexible followed by the three and six year old models in flexion and extension, the three year old pediatric model was the most flexible under compression followed by the six and one year old models. The differing biomechanical responses among different pediatric groups were ascribed to the individual developmental anatomical features. The present findings of significant increase in biomechanical response due to local geometry and material property changes emphasize the need to consider the developmental anatomical features in the pediatric structures to better predict their biomechanical behavior.