Hydrogenation of Zr-Based Quasicrystals

In this chapter, results of our recent investigations on the hydrogenation behavior of Zr-based quasicrystalline alloys and its effect on their structural and microhardness behavior have been discussed. The microstructural changes with respect to the addition of Ti and their correlation with hydrogen storage characteristics of (Zr69.5Al7.5Cu12 Ni11)100−xTix (x = 0, 4 and 12) quasicrystalline alloys have been studied. The substitution of Ti affects the nucleation and growth characteristics of nano-quasicrystals. The grain size of quasicrystals decreases with addition of Ti. The hydrogen uptake capacity of partially quasicrystalline alloys has been improved by the addition of Ti. The alloys with x = 0, 4, and 12 absorbed 1.20 wt.%, 1.38 wt.%, and 1.56 wt.% of hydrogen, respectively. A significant effect on the structure/microstructure and mechanical behavior of (Zr69.5Al7.5Cu12Ni11)100−xTix quasicrystalline alloys due to hydrogenation has been observed. The change in the microhardness behavior has been discussed based on microstructural variation resulting to Ti addition. The study is focused on investigations of these materials to understand the structure (microstructure)-property correlations

α-Amylase immobilization onto functionalized graphene nanosheets as scaffolds: Its characterization, kinetics and potential applications in starch based industries

Abstractα-Amylase is imperative for starch and its deriviatized industries. Functionalized graphene sheets were tailored and optimized as scaffold for α-amylase immobilization using Response Surface Methodology based on Box–Behnken design, with an overall immobilization efficiency of 85.16%. Analysis of variance provided adequacy to the mathematical model for further studies. Native and immobilized functionalized graphene were characterized using transmission and scanning electron microscopy, followed by Fourier transform infrared (FTIR) spectroscopy. Wheat α-amylase conjugated with functionalized graphene sheets were visually evident on transmission and scanning micrographs while the FTIR spectra showed interplay of various chemical interactions and bonding, during and after immobilization. Optimum pH and optimum temperature for immobilized enzyme though remained unchanged but showed broader range whereas Km showed a slight decrease (1.32mg/mL). It also showed enhanced thermal and storage stability and retained 73% residual activity after 10 uses. These ensemble of properties and non-toxic nature of functionalized graphene, makes it viable to be absorbed commercially in starch processing industries

Maternal correlates of birth weight of newborn: A hospital based study

Background: weight of the baby at birth is considered to be a major determinant of future health and survival of the child. It is one of the important factors which determine the readiness with which the newborn baby adjusts to its surrounding. Many maternal socio-biological factors influence birth weight. Objective: To determine maternal socio-biological factors influencing birth weight of newborn. Methodology: Hospital based cross- sectional study undertaken in Obstetrics and Gynaecology ward of Nehru hospital, Gorakhpur. The study period extended from July 2011 to August 2012. The study subject included recently delivered mothers and data was collected on semi-structured interview schedule to know various socio-biological variables such as mother’s age, parity, inter-pregnancy interval etc, influencing the low birth weight of newborn. Chi-Square test was applied to observe the significance of association.  Results: The overall proportion of low birth weight baby came out to be 32.06%. Out of various socio-biological factors taken the factors which came out to be statistically significant were age of mother, parity, inter-pregnancy interval, SLI, education. The factors which were not statistically significant were father’s education, religion. Conclusions:  It was concluded that teenage pregnancy, non-utilization of antenatal care practices, anaemia, illiteracy are unfavorable predictors of birth weight of newborn babies

Scalable synthesis of aligned carbon nanotubes bundles using green natural precursor: neem oil

Practical application of aligned carbon nanotubes (ACNTs) would have to be determined by a matter of its economical and large-scale preparation. In this study, neem oil (also named Margoaa oil, extracted from the seeds of the neem--Azadirachta indica) was used as carbon source to fabricate the bundles of ACNTs. ACNTs have been synthesized by spray pyrolysis of neem oil and ferrocene mixture at 825°C. The major components of neem oil are hydrocarbon with less amount of oxygen, which provided the precursor species in spray pyrolysis growth of CNTs. The bundles of ACNTs have been grown directly inside the quartz tube. The as-grown ACNTs have been characterized through Raman spectroscopy, scanning and transmission electron microscopic (SEM/TEM) techniques. SEM images reveal that the bundles of ACNTs are densely packed and are of several microns in length. High-resolution TEM analysis reveals these nanotubes to be multi-walled CNTs. These multi-walled CNTs were found to have inner diameter between 15 and 30 nm. It was found that present technique gives high yield with high density of bundles of ACNTs

Genome-wide discovery of OsHOX24-binding sites and regulation of desiccation stress response in rice

HD-ZIP I subfamily of homeobox transcription factors (TFs) are involved in abiotic stress responses and plant development. Previously, we demonstrated the role of OsHOX24, a member of HD-ZIP I subfamily, in abiotic stress responses. In this study, we identified downstream targets of OsHOX24 under control and desiccation stress conditions via chromatin immunoprecipitation-sequencing (ChIP-seq) approach in wild-type and OsHOX24 over-expression transgenic in rice. OsHOX24-binding sites in each sample and differential binding sites between the samples were detected at various genomic locations, including genic and intergenic regions. Gene ontology enrichment analysis revealed that OsHOX24 direct target genes were involved in several biological processes, including plant development, ABA-mediated signalling pathway, ubiquitin-dependent protein catabolic process, ion transport, abiotic and biotic stress responses besides transcriptional and translational regulation. The enrichment of several cis-regulatory motifs representing binding sites of other TFs, such as ABFs, ERF1, MYB1, LTREs and SORLIP2, suggested the involvement of OsHOX24 in a complex regulatory network. These findings indicate that OsHOX24-mediated desiccation stress regulation involves modulation of a plethora of target genes, which participate in diverse pathways in rice

Functionalized graphene sheets as immobilization matrix for Fenugreek β-amylase: enzyme kinetics and stability studies.

β-Amylase finds application in food and pharmaceutical industries. Functionalized graphene sheets were customised as a matrix for covalent immobilization of Fenugreek β-amylase using glutaraldehyde as a cross-linker. The factors affecting the process were optimized using Response Surface Methodology based Box-Behnken design of experiment which resulted in 84% immobilization efficiency. Scanning and Transmission Electron Microscopy (SEM, TEM) and Fourier Tansform Infrared (FTIR) spectroscopy were employed for the purpose of characterization of attachment of enzyme on the graphene. The enzyme kinetic studies were carried out for obtaining best catalytic performance and enhanced reusability. Optimum temperature remained unchanged, whereas optimum pH showed shift towards acidic range for immobilized enzyme. Increase in thermal stability of immobilized enzyme and non-toxic nature of functionalized graphene can be exploited for production of maltose in food and pharmaceutical industries

Maternal correlates of birth weight of newborn: A hospital based study

Background: weight of the baby at birth is considered to be a major determinant of future health and survival of the child. It is one of the important factors which determine the readiness with which the newborn baby adjusts to its surrounding. Many maternal socio-biological factors influence birth weight. Objective: To determine maternal socio-biological factors influencing birth weight of newborn. Methodology: Hospital based cross- sectional study undertaken in Obstetrics and Gynaecology ward of Nehru hospital, Gorakhpur. The study period extended from July 2011 to August 2012. The study subject included recently delivered mothers and data was collected on semi-structured interview schedule to know various socio-biological variables such as mother’s age, parity, inter-pregnancy interval etc, influencing the low birth weight of newborn. Chi-Square test was applied to observe the significance of association.  Results: The overall proportion of low birth weight baby came out to be 32.06%. Out of various socio-biological factors taken the factors which came out to be statistically significant were age of mother, parity, inter-pregnancy interval, SLI, education. The factors which were not statistically significant were father’s education, religion. Conclusions:  It was concluded that teenage pregnancy, non-utilization of antenatal care practices, anaemia, illiteracy are unfavorable predictors of birth weight of newborn babies

Functionalized graphene sheets as immobilization matrix for Fenugreek β-amylase: Enzyme kinetics and stability studies

<p>Statistical evaluation of the model generated using the Response Surface Methodology based Box-Behnken design of  experiment for optimization of factors affecting immobilization of Fenugreek β-amylase on graphene sheets.</p