183 research outputs found
Particulate Suspension Blood Flow through a Stenosed Catheterized Artery
The flow of blood through a narrow catheterized artery with an overlapping stenosis has been investigated. To account for the presence of red cells, blood has been represented by a macroscopic two-phase model (i.e., a suspension of erythrocytes in plasma). The expression for the flow characteristics-the flow rate, the impedance (resistance to flow), the wall shear stress in the stenotic region, the shear stresses at the stenosis two throats and at critical height of the stenosis, has been derived. It is found that the impedance increases with the catheter size, with the hematocrit and also with the stenosis size (height and length). A significant increase in the magnitude of the impedance and other flow characteristics occur even for a small increase in the catheter size. Variations in the magnitude of all the flow characteristics are observed to be similar in nature with respect to any parameter given
Phycoremediation of Dairy Wastewater by Microalgae for elimination of organic pollution load
The present study aims to demonstrate the potential of microalgae Chlorococcum humicola for treatment of dairy industry effluent and reduction of its pollution load with the cultivation of microalgae in the same effluent. Dairy industry wastewater supplies the required nutrients for the growth of C. humicola and its growth was comparatively higher in 50 % dairy industry effluent as compare to Bold basal growth medium. Optimization of growth parameters of algae showed that growth of C. humicola was favoured by alkaline pH and optimum growth was observed at pH 8, whereas acidic pH does not favour the growth of selected algae. The exponential growth phase of C. humicola was achieved between 3-7 days, at 20˚C temperature, a further increase in temperature decreases the algal growth. The results for the effect of different concentration of dairy wastewater (0, 10, 25, 50, 75 and 100 %) on biochemical content (protein, chlorophyll a, carbohydrate) of C. humicola revealed that 50 % wastewater concentration was more efficient for enhancement of biochemical content of microalgae as compare to control. The result further showed considerable reduction in the organic pollution load of dairy wastewater as biological oxygen demand (BOD) and chemical oxygen demand (COD) reduced to 72 and 78 % respectively, after 15 days of treatment with C. humicola. The results also showed a reduction in the nutrient concentration of dairy wastewater such as nitrate, phosphate and sulphate by 92, 43, 62 % respectively, after 10 days of treatment and 96, 67 and 78 % respectively, after 15 days of microalgal treatment as compared to control (without microalgae). These findings suggested that dairy industry wastewater was a good nutrient supplement and can be directly used for mass cultivation of C. humicola without requiring additional nutrient supplements and also the microalgae C. humicola has a great potential for the treatment of dairy industry wastewate
A Two-layered Non-Newtonian Arterial Blood Flow through an Overlapping Constriction
The problem of blood flow through an overlapping constriction in arteries is investigated in this work. To account for the non-Newtonian behavior and the peripheral layer, blood has been represented by a two-fluid model, consisting of a core region of suspension of all the erythrocytes assumed to be a Casson fluid and a peripheral layer of plasma (Newtonian fluid). The expression for the flow characteristics, namely, the impedance, the wall shear stress, the shear stress at the stenosis throats and at the critical height of the stenosis has been derived. Moreover, we present some results concerning the dependence of these quantities on the geometrical parameters
Effect of substrate on physical properties of pulse laser deposited ZnO thin films
ZnO is a II-VI group semiconductor material with a large direct band gap. Zinc oxide films are prepared by Pulse Laser Deposition (PLD) technique on to highly cleaned glass, ITO coated glass and Si (100) substrates. The as-prepared films are characterized by optical absorption and transmission spectra and X-Ray Diffraction (XRD) patterns. The absorption spectra and transmission spectra of the deposited ZnO films are taken from UV-VIS-NIR Spectrophotometer at room temperature. The band gap of the ZnO film is determined from absorption measurements using Tauc relation for direct band gap materials while optical constants of the ZnO film are determined from transmission measurements by Manifacier's envelope method. The effect of lattice mismatching between the lattices of the substrate and of the deposited material on the structural properties and crystallite size of the deposited films are studied using XRD patterns of ZnO films
Prevalence of Need of Orthodontic Treatment in 7–16-Year-Old School Children in Udaipur City, India
Objective:The study aimed to estimate the need of orthodontic treatment in 7-16-year-old school children in Udaipur city, India.Methods:This cross sectional study enrolled 1029 subjects (661 males and 368 females) belonging to Udaipur city, Rajasthan, India. Subjects who had not undergone orthodontic treatment were randomly selected. The need for orthodontic treatment was assessed using the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN) by the same calibrated examiner. Collected data were quantitatively analyzed, and the difference pertaining to prevalence between males and females was measured using the chi-square test.Results:A Grade 1 IOTN score was observed in 48.4% of the population. Grade 2 was observed in 22.9% of the population. A significant difference was noted for the prevalence of Grades 1, 2, and 3 between male and female children, with male children showing greater prevalence of malocclusion grades. Grades 4 and 5, which were noted less frequently, did not show a significant difference with respect to sex.Conclusion:A higher percentage of the sample required moderate orthodontic treatment. This necessitates proper education and motivation to undergo orthodontic treatment
MycoRRdb: A Database of Computationally Identified Regulatory Regions within Intergenic Sequences in Mycobacterial Genomes
The identification of regulatory regions for a gene is an important step towards deciphering the gene regulation. Regulatory regions tend to be conserved under evolution that facilitates the application of comparative genomics to identify such regions. The present study is an attempt to make use of this attribute to identify regulatory regions in the Mycobacterium species followed by the development of a database, MycoRRdb. It consist the regulatory regions identified within the intergenic distances of 25 mycobacterial species. MycoRRdb allows to retrieve the identified intergenic regulatory elements in the mycobacterial genomes. In addition to the predicted motifs, it also allows user to retrieve the Reciprocal Best BLAST Hits across the mycobacterial genomes. It is a useful resource to understand the transcriptional regulatory mechanism of mycobacterial species. This database is first of its kind which specifically addresses cis-regulatory regions and also comprehensive to the mycobacterial species. Database URL: http://mycorrdb.uohbif.in
In-situ local phase-transitioned MoSe2 in La0.5Sr0.5CoO3-?? heterostructure and stable overall water electrolysis over 1000 hours
Developing efficient bifunctional catalysts for overall water splitting that are earth-abundant, cost-effective, and durable is of considerable importance from the practical perspective to mitigate the issues associated with precious metal-based catalysts. Herein, we introduce a heterostructure comprising perovskite oxides (La0.5Sr0.5CoO3?????) and molybdenum diselenide (MoSe2) as an electrochemical catalyst for overall water electrolysis. Interestingly, formation of the heterostructure of La0.5Sr0.5CoO3????? and MoSe2 induces a local phase transition in MoSe2, 2???H to 1???T phase, and more electrophilic La0.5Sr0.5CoO3????? with partial oxidation of the Co cation owing to electron transfer from Co to Mo. Together with these synergistic effects, the electrochemical activities are significantly improved for both hydrogen and oxygen evolution reactions. In the overall water splitting operation, the heterostructure showed excellent stability at the high current density of 100???mA???cm???2 over 1,000???h, which is exceptionally better than the stability of the state-of-the-art platinum and iridium oxide couple
Structure and Age Jointly Influence Rates of Protein Evolution
What factors determine a protein's rate of evolution are actively debated. Especially unclear is the relative role of intrinsic factors of present-day proteins versus historical factors such as protein age. Here we study the interplay of structural properties and evolutionary age, as determinants of protein evolutionary rate. We use a large set of one-to-one orthologs between human and mouse proteins, with mapped PDB structures. We report that previously observed structural correlations also hold within each age group – including relationships between solvent accessibility, designabililty, and evolutionary rates. However, age also plays a crucial role: age modulates the relationship between solvent accessibility and rate. Additionally, younger proteins, despite being less designable, tend to evolve faster than older proteins. We show that previously reported relationships between age and rate cannot be explained by structural biases among age groups. Finally, we introduce a knowledge-based potential function to study the stability of proteins through large-scale computation. We find that older proteins are more stable for their native structure, and more robust to mutations, than younger ones. Our results underscore that several determinants, both intrinsic and historical, can interact to determine rates of protein evolution
Proteins with Complex Architecture as Potential Targets for Drug Design: A Case Study of Mycobacterium tuberculosis
Lengthy co-evolution of Homo sapiens and Mycobacterium tuberculosis, the main causative agent of tuberculosis, resulted in a dramatically successful pathogen species that presents considerable challenge for modern medicine. The continuous and ever increasing appearance of multi-drug resistant mycobacteria necessitates the identification of novel drug targets and drugs with new mechanisms of action. However, further insights are needed to establish automated protocols for target selection based on the available complete genome sequences. In the present study, we perform complete proteome level comparisons between M. tuberculosis, mycobacteria, other prokaryotes and available eukaryotes based on protein domains, local sequence similarities and protein disorder. We show that the enrichment of certain domains in the genome can indicate an important function specific to M. tuberculosis. We identified two families, termed pkn and PE/PPE that stand out in this respect. The common property of these two protein families is a complex domain organization that combines species-specific regions, commonly occurring domains and disordered segments. Besides highlighting promising novel drug target candidates in M. tuberculosis, the presented analysis can also be viewed as a general protocol to identify proteins involved in species-specific functions in a given organism. We conclude that target selection protocols should be extended to include proteins with complex domain architectures instead of focusing on sequentially unique and essential proteins only
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