Isoamylacetate production by entrapped and covalently bound Candida rugosa and porcine pancreatic lipases

Candida rugosa lipase (CRL) and porcine pancreatic lipase (PPL) were immobilised by entrapping and also by covalent binding for use in synthesis of isoamyl acetate (IAAc), which has a typical banana flavour. Lipase entrapment was carried out by dripping sodium alginate (Na-Alg)-chitosan (Chi)-lipase mixture into CaCl₂-glutaraldehyde (GAL) solution to obtain Ca-Alg/Chi_CRL/PPL. Immobilisation conditions were optimised as 1.5% Na-Alg, 1.5% chitosan and 0.15% GAL. Ca-Alg/Chi_CRL/PPL samples showed the highest activity when they were dried upon reaching 27% of their initial weights. Covalent binding was achived with Chi modified with spacerarm via glutaraldehyde to get Chi_CRL/PPL. The highest IAAc production was observed when 1,3-diaminopropane was used as a spacer arm. The best ester yield was achieved in heptane, at 40 and 45 °C reaction temperatures, 50 mM IAA and 50 or 75 mM AA concentrations. The amount of IAAc was nearly 10 times higher for the batch type than for the continuous packed bed column reactor.     

Discriminating schizophrenia and schizo-obsessive disorder: a structural MRI study combining VBM and machine learning methods

Schizo-obsessive disorder is characterized by the clinical syndrome in which comorbid obsessive–compulsive disorder accompanies schizophrenia. A substantial number of studies have investigated the neuropsychological and clinical differences between schizophrenia and schizo-obsessive disorder. However, the neurostructural differences between these two groups have not been adequately investigated. The aim of this study was to explore gray matter differences between schizophrenia and schizo-obsessive patients using voxel-based morphometry and support vector machines combined with feature selection algorithm. Twenty-three schizophrenia and 23 schizo-obsessive patients matched by age, gender and handedness were recruited. Clinical assessments were completed in addition to high-resolution structural MRI scanning. Group differences were investigated using contrast maps, and significant regions were subjected to a feature selection and support vector machine hybrid model. In addition, voxel-of-interest values for the commonly shared brain areas between schizophrenia and OCD reported in previous meta-analyses were also used as inputs in this step. The results showed that schizo-obsessive patients had greater gray matter densities in paracentral areas (including supplementary motor area) and middle cingulate gyrus than schizophrenia patients. These brain areas together with the fronto-subcortical areas could successfully discriminate two groups with an accuracy of 78.26 %. Our results provide the first neuroanatomical evidence that schizo-obsessive disorder and schizophrenia may be two distinct clinical entities. Based on these findings, considering schizo-obsessive disorder as a subtype of schizophrenia is discernible.

     

CPU–RAM-based energy-efficient resource allocation in clouds

The Journal of Supercomputing - Cloud computing provides online services and solutions for dynamic and on-demand resource provisioning. These resources consume high energy leading to higher...     

Loading analysis of detachable joints by the acoustic method

The use of the acoustic method for measuring stresses in detachable joints is considered. It is characterized by improved accuracy, can be applied in an automated mode, and allows measurements in large parts in the sonic test area. The data on the instrumental facilities of the method are given and cases of their use in real designs are described.     

Respiratory effects in people exposed to arsenic via the drinking water and tobacco smoking in southern part of Pakistan

In this study, a survey has been conducted during 2005-2007 on surface and groundwater arsenic (As) contamination and its impact on the health of local population, of villages located on the banks of Manchar lake, southern part of Sindh, Pakistan. We have also assessed the relationship between arsenic exposure through respiratory disorders in male subjects with drinking water and smoking cigarettes made from tobacco grown in agricultural land irrigated with As contaminated lake water. The biological samples (blood and scalp hair) were collected from As exposed subjects (100% smokers) and age matched healthy male subjects (40.2% smoker and 59.8% non smokers) belong to unexposed areas for comparison purposes. The As concentration in drinking water (surface and underground water), agricultural soil, cigarette tobacco and biological samples were determined by electrothermal atomic absorption spectrometry. The range of As concentrations in lake water was 35.2-158 µg/L (average 97.5 µg/L), which is 3-15 folds higher than permissible limit of World Health Organization (WHO, 2004). While the As level in local cigarette tobacco was found to be 3-6 folds higher than branded cigarettes (0.37-0.79 µg/g). Arsenic exposed subjects (with and without RD) had significantly elevated levels of As in their biological samples as compared to referent male subject of unexposed area. These respiratory effects were more pronounced in individuals who had also As induced skin lesions. The linear regressions showed good correlations between As concentrations in water versus hair and blood samples of exposed subjects with and without respiratory problems.     

Structure-Activity Relationship Analysis of Dialkyltin (IV) Dicarboxylates as Catalysis for the Crosslinking of α, ω-Dihydroxy-Polydimethylsiloxane

Silicon - A number of homologous dialkyl tin (IV) dicarboxylate (organotin compounds), varying with respect to the length of alkyl groups have been studied with respect to their catalytic activity...     

Internal Electric Field Behavior of Cadmium Zinc Telluride Radiation Detectors Under High Carrier Injection

The behavior of the internal electric field of nuclear-radiation detectors substantially affects detector performance. We investigated the distribution of the internal field in cadmium zinc telluride (CZT) detectors under high carrier injection. We noted the build-up of a space-charge region near the cathode that produces a built-in field opposing the applied field. Its presence entails the collapse of the electric field in the rest of the detector, other than the portion near the cathode. Such a space-charge region originates from serious hole trapping in CZT. The device’s operating temperature greatly affects the width of the space-charge region. With increasing temperature from 5°C to 35°C, its width expanded from about one-sixth to one-half of the total depth of the detector.     

Synthesis and characterization of completely soluble and highly thermally stable PANI-DBSA salts

This paper presents synthesis and characterization of soluble polyaniline-dodecylbenzenesulfonic acid (PANI-DBSA) via inverse polymerization. A mixture of chloroform and 2-butanol was used as dispersion medium for the first time. This polymerization pathway leads to the formation of PANI-DBSA salts which are completely soluble in a number of common organic solvents (such as DMSO, DMF, chloroform and in a mixture of toluene) and 2-propanol (so far highest number of solvents for solubility of PANI). The influence of synthesis parameters such as concentration of aniline, benzoyl peroxide and dodecylbenzenesulfonic acid (DBSA) on the yield and other properties of the resulting PANI-DBSA salts was studied. Further characterization of the synthesized materials was done with the help of viscosity measurements, UV–Vis spectroscopy, cyclic voltammetry, XRD and SEM. TGA was used to analyze the thermal properties of synthesized polymer. The synthesized salts were found to be highly stable.     

The solution of multipoint boundary value problems by the Optimal Homotopy Asymptotic Method

In this work, we solve multipoint boundary value problems using the Optimal Homotopy Asymptotic Method (OHAM).The proposed method is tested upon several problems from the literature and the results are compared with the available exact solution. This method provides easy tools to control the convergence region of approximating solution series where ever necessary.