55 research outputs found

    Microbial Production of Amylase from Cassava Waste

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    Bacterium mura was isolated from cassava waste, (Tamil Nadu, India) for the production of extracellular amylase. On screening for amylase producing bacteria, 5 isolates showed positive results, of which Bacterium mura showed best amylase activity. The optimal conditions for the amylase activity were found at pH 6.0 (39 U/ml) and at temperature 37°C. Amylase activity was found to be higher when lactose (31 U/ml), casein, barley (42 U/ml) and SDS (32 U/ml) were used as the carbon source, nitrogen source, agro waste source and as additives respectively. The enzyme was partially purified by dialysis and the molecular mass was found to be 65kDa by SDS-PAGE. The partially purified and crude amylase was confirmed by zymogram. The partially purified amylase was used in bread making, which improved the softening of the bread and was used as a de-sizing agent

    Explaining the Atypical Reaction Profiles of Heme Enzymes with a Novel Mechanistic Hypothesis and Kinetic Treatment

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    Many heme enzymes show remarkable versatility and atypical kinetics. The fungal extracellular enzyme chloroperoxidase (CPO) characterizes a variety of one and two electron redox reactions in the presence of hydroperoxides. A structural counterpart, found in mammalian microsomal cytochrome P450 (CYP), uses molecular oxygen plus NADPH for the oxidative metabolism (predominantly hydroxylation) of substrate in conjunction with a redox partner enzyme, cytochrome P450 reductase. In this study, we employ the two above-mentioned heme-thiolate proteins to probe the reaction kinetics and mechanism of heme enzymes. Hitherto, a substrate inhibition model based upon non-productive binding of substrate (two-site model) was used to account for the inhibition of reaction at higher substrate concentrations for the CYP reaction systems. Herein, the observation of substrate inhibition is shown for both peroxide and final substrate in CPO catalyzed peroxidations. Further, analogy is drawn in the “steady state kinetics” of CPO and CYP reaction systems. New experimental observations and analyses indicate that a scheme of competing reactions (involving primary product with enzyme or other reaction components/intermediates) is relevant in such complex reaction mixtures. The presence of non-selective reactive intermediate(s) affords alternate reaction routes at various substrate/product concentrations, thereby leading to a lowered detectable concentration of “the product of interest” in the reaction milieu. Occam's razor favors the new hypothesis. With the new hypothesis as foundation, a new biphasic treatment to analyze the kinetics is put forth. We also introduce a key concept of “substrate concentration at maximum observed rate”. The new treatment affords a more acceptable fit for observable experimental kinetic data of heme redox enzymes

    Advancement of Supercapacitor in Automotive Applications

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    The rising use of fossil fuels and the resulting rise in environmental harm have fueled the advancement of automobiles that are fuel-efficient. A severe existential challenge facing the planet earth has given rise to hybrid electric vehicles (HEVs), which have developed from their incipient stage and are shown promise as a solution. Additionally, when needed to produce peaking power, batteries' efficiency is reduced. Instead, supercapacitors have smaller energy storage capacity but can withstand peaking power. Designing a clever method to manage the energy balance between a supercapacitor and a battery is the main goal of this research. Different topologies are used to study the battery-supercapacitor energy storage system in great detail. Nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and other harmful gases are less released when a battery-supercapacitor energy storage system is integrated. Additionally, it can lower the load on the battery, extending its life and improving its performance in HEVs

    Advancement of Supercapacitor in Automotive Applications

    No full text
    The rising use of fossil fuels and the resulting rise in environmental harm have fueled the advancement of automobiles that are fuel-efficient. A severe existential challenge facing the planet earth has given rise to hybrid electric vehicles (HEVs), which have developed from their incipient stage and are shown promise as a solution. Additionally, when needed to produce peaking power, batteries' efficiency is reduced. Instead, supercapacitors have smaller energy storage capacity but can withstand peaking power. Designing a clever method to manage the energy balance between a supercapacitor and a battery is the main goal of this research. Different topologies are used to study the battery-supercapacitor energy storage system in great detail. Nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and other harmful gases are less released when a battery-supercapacitor energy storage system is integrated. Additionally, it can lower the load on the battery, extending its life and improving its performance in HEVs

    Reduced VDAC1, Maintained Mitochondrial Dynamics and Enhanced Mitochondrial Biogenesis in a Transgenic Tau Mouse Model of Alzheimer’s Disease

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    Alzheimer’s disease (AD) is one of the most common forms of neurodegeneration, defined by reduced cognitive function, which is caused by the gradual death of neurons in the brain. Recent studies have shown an age-dependent rise in the levels of voltage-dependent anion channel 1 (VDAC1) in AD. In addition, we discovered an aberrant interaction between VDAC1 and P-TAU in the brains of AD patients, which led to abnormalities in the structural and functional integrity of the mitochondria. The purpose of our study is to understand the protective effects of reduced VDAC1 against impaired mitochondrial dynamics and defective mitochondrial biogenesis in transgenic TAU mice. Recently, we crossed heterozygote VDAC1 knockout (VDAC1+/−) mice with transgenic TAU mice to obtain double-mutant VDAC1+/−/TAU mice. Our goal was to evaluate whether a partial decrease in VDAC1 lessens the amount of mitochondrial toxicity in transgenic Tau (P301L) mice. We found that mitochondrial fission proteins were significantly reduced, and mitochondrial fusion and biogenesis proteins were increased in double-mutant mice compared to TAU mice. On the basis of these discoveries, the current work may have significance for the development of reduced-VDAC1-based treatments for individuals suffering from AD as well as other tauopathies

    Behavioral Evidence for a Tau and HIV-gp120 Interaction

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    Despite successful virologic control with combination antiretroviral therapy (cART), about half of people living with the human immunodeficiency virus-1 (HIV) develop an HIV-associated neurocognitive disorder (HAND). It is estimated that 50% of individuals who are HIV-positive in the United States are aged 50 years or older. Therefore, a new challenge looms as individuals living with HIV increase in age. There is concern that Alzheimer’s disease (AD) may become prevalent with an earlier onset of cognitive decline in people living with HIV (PLWH). Clinical data studies reported the presence of AD biomarkers in PLWH. However, the functional significance of the interaction between HIV or HIV viral proteins and AD biomarkers is still not well studied. The main goal of the present study is to address this knowledge gap by determining if the HIV envelope glycoprotein 120 (HIV-gp120) can affect the cognitive functions in the Tau mouse AD model. Male Tau and age-matched, wild-type (WT) control mice were treated intracerebroventricularly (ICV) with HIV-gp120. The animals were evaluated for cognitive function using a Y-maze. We found that HIV-gp120 altered cognitive function in Tau mice. Notably, HIV-gp120 was able to promote a cognitive decline in transgenic Tau (P301L) mice compared to the control (HIV-gp120 and WT). We provide the first in vivo evidence of a cognitive interaction between an HIV viral protein and Tau mice

    A Review on Principles, Theories and Materials for Self Sensing Concrete for Structural Applications

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    Self-sensing concrete is a smart material known for its cost-effectiveness in structural health-monitoring areas, which converts the external stimuli into a stress/strain sensing parameter. Self-sensing material has excellent mechanical and electrical properties that allow it to act as a multifunctional agent satisfying both the strength and structural health-monitoring parameters. The main objective of this review is to understand the theories and principles behind the self-sensing practices. Many review papers have focused on the different types of materials and practices that rely on self-sensing technology, and only a few articles have discussed the theories involved. Understanding the mechanism and the theories behind the conduction mechanism is necessary. This review paper provides an overview of self-sensing concrete, including the principles such as piezoresistivity and piezopermittivity; the tunnelling effect, percolation threshold, and electrical circuit theories; the materials used and methods adopted; and the sensing parameters. The paper concludes with an outline of the application of self-sensing concrete and future recommendations, thus providing a better understanding of implementing the self-sensing technique in construction

    Predisposition of angiotensin-converting enzyme deletion/deletion genotype to coronary artery disease with type 2 diabetes mellitus in South India

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    Background: Worldwide, South Asians contribute to a high proportion of coronary artery disease (CAD) burden, mainly attributed to a high prevalence of diabetes. Early identification of such high-risk individuals would enable aggressive disease modification and prevention of complications. Definition of susceptible genotypes early in the course of disease may be one such avenue for reduction in morbidity and mortality from CAD. Aim: Our study was aimed to investigate the insertion/deletion polymorphism of angiotensin-converting enzyme (ACE I/D) gene and susceptibility to CAD in patients with type 2 diabetes mellitus (T2DM) in a South Indian population. Subjects and Methods: ACE (I/D) genotyping was performed by polymerase chain reaction specific primer for 187 CAD patients and 185 age- and sex-matched controls. Results: We observed that the ACE“II” genotype was found to be significantly associated with CAD patients (odds ratio [OR] = 1.689; P = 0.028). However, multiple logistic regression analysis revealed that ACE “DD” genotype was found to be most predominant risk factor for CAD patients with T2DM (OR = 6.118; P = 0.001). Conclusion: Our results showed that ACE (I/D) genotypes and alleles presented functional dimorphism in the development of CAD and CAD with T2DM patients in South India. This finding may be extremely useful in identifying subsets of patients where early aggressive treatment of risk factors is warranted

    of the Forward Link Only (FLO) Air Interface. The FLO Air

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    Abstract—This paper provides an overview of the physical laye
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