Free Vibration Analysis of Twisted Functionally Graded Material Plates

The present paper will explore the free vibration behavior of thin twisted functionally graded material (FGM) plates. The vibration analysis is done using finite element method. An 8 noded shell element is used for finite element calculations. To model the FGM section, continuous variation in the material property along the thickness is approximated to a laminated composite section consisting of a number of layers and each layer is considered as isotropic. The material property in each layer is determined using power law. Material density, Young's modulus and Poisson's ratio change along the thickness based on power law. The first order shear deformation theory is used in the analysis of pretwisted FGM plate. Convergence of fundamental frequencies is observed, with an increase in mesh size and the number of layers in the thickness direction. To validate the finite element model, for different boundary conditions, the free vibration results are compared with analytical studies and experimental studies. Having fixed the mesh size and number of layers required to represent the material property variation along the depth, the changes in frequencies with variation in angle of twist and material property index is studied. The effect of geometric variables such as gradient index, aspect ratio, side to thickness ratio and angle of twist on the free vibration of cantilever twisted plates is studied. Temperature dependent material properties are considered as well as nonlinear material property variation along the thickness due to temperature. The influence of thermal gradient along the thickness direction on the free vibration of cantilever twisted plates is studied

Magnetic fabrics in characterization of magma emplacement and tectonic evolution of the Moyar Shear Zone, South India

AbstractThe Moyar Shear Zone (MSZ) of the South Indian granulite terrain hosts a prominent syenite pluton (∼560 Ma) and associated NW-SE to NE-SW trending mafic dyke swarm (∼65 Ma and 95 Ma). Preliminary magnetic fabric studies in the mafic dykes, using Anisotropy of Magnetic Susceptibly (AMS) studies at low-field, indicate successive emplacement and variable magma flow direction. Magnetic lineation and foliation in these dykes are identical to the mesoscopic fabrics in MSZ mylonites, indicating shear zone guided emplacement. Spatial distribution of magnetic lineation in the dykes suggests a common conduit from which the source magma has been migrated. The magnetic foliation trajectories have a sigmoidal shape to the north of the pluton and curve into the MSZ suggesting dextral sense of shear. Identical fabric conditions for magnetic fabrics in the syenite pluton and measured field fabrics in mylonite indicate syntectonic emplacement along the Proterozoic crustal scale dextral shear zone with repeated reactivation history

A Study on factors influencing the outcome of thrombolysis in Acute Myocardial Infarction

INTRODUCTION : Coronary heart disease (CHD) is a worldwide health epidemic. In the United States, for example, it is estimated that 13.7 million Americans have CHD, including more than 7.2 million individuals who already have had a myocardial infarction.1,2 From the 1960’s to the 1990’s the CAD prevalence increased two fold (from 2% to 4% )in rural India and three fold ( from 3.45 to 9.45%) in Urban India. The prevalence is even higher in South India (13% urban and 7% rural). In 1990, 25% deaths in India were attributable to cardiovascular disease compared to diarrheal disease ,12% due to respiratory infections and 5% due to tuberculosis47. In the group of persons older than 30 years of age, 213 per 100,000 individuals have CHD.1 Although agespecific events related to CHD have fallen dramatically in the last few decades, the overall prevalence has risen as populations age and patients survive the initial coronary or cardiovascular event . Worldwide 30 percent of all deaths can be attributed to cardiovascular disease of which more than half are caused by CAD. Coronary Heart disease has been defined as impairment of heart function due to inadequate blood flow to heart compared to its needs caused by obstructive changes in the coronary circulation to the heart. Thrombolytic therapy has been consistently proven to reduce the mortality and morbidity. Inspite of this it has been recognized that thrombolytic therapy has failed in significant population. There is lot of room for improvement. We need to identify the factors that are responsible for failure of thrombolysis. In this background we decided to look into our own patients who receive streptokinase for acute myocardial Infarction, in the coronary care unit of Coimbatore Medical College Hospital. AIM OF THE STUDY : 1. To find out the overall success rate of thrombolysis in coronary care unit of Coimbatore medical college hospital. 2. To find out whether the following parameters influence the outcome of thrombolysis. 1. Age, 2. Sex, 3. Pre-infarction angina, 4. Alcohol intake, 5. Smoking status, 6. Pre existing systemic hypertension, 7. Diabetes mellitus, 8. Type of Myocardial Infarction., 9. Time interval between the onset of pain and the initiation of thrombolytic therapy. MATERIALS AND METHODS : PLACE OF STUDY : This study was conducted in the coronary care unit of Coimbatore Medical College Hospital, Coimbatore. PERIOD OF STUDY : From MARCH 2009 – OCTOBER 2010. DESIGN : Observational prospective cohort study of patients receiving streptokinase for acute myocardial infarction. A total of 83 patients were included in the study. METHODOLOGY : Subject selection: 1. Inclusion criteria: a) Presence of typical chest pain suggestive of Acute myocardial infarction along with ECG evidence of acute myocardial infarction. Criteria for thrombolysis being 2mm or more ST elevation in two contiguous limb leads. b) Time window of 12 hrs from the onset of pain to the initiation of thrombolysis. 2. Exclusion criteria: a) Late thrombolysis (more than 12 hrs from the onset of pain). b) Recurrent myocardial infarction. c) Presence of bundle branch block. d) Development of pericarditis. RESULTS : A total of 83 patients were studied. Their age ranged from 34 – 76 years (mean 55.03 yrs).68 of them were males (82%) and 15 females (18%) 20 of them were hypertensives (24%). 44 people were smokers (53%) and 29 (59%) consumed alcohol. 23 patients experienced preinfarction angina (28%). 50 patients had anterior wall infarction (60%) and 33 patients (40%) had inferior infarction. CONCLUSION : 1. In this study the overall success rate of Thrombolysis was 53 %. 2. The outcome was worse in those who aged more than 60 years. But it was not statistically significant. 3. Gender was not found to influence the success rate of thrombolysis. 4. Pre infarction angina had no effect on the success rate of thrombolysis. 5. Better success rate has been seen in those consuming alcohol which was not statistically significant. 6. Smokers had a lesser success rate than non smokers but it did not reach any statistical significance. 7. Hypertensives did not show any difference with non hypertensives in the success rate. 8. Diabetics did not differ from non diabetics with respect to the success rate of thrombolysis. 9. Inferior wall myocardial infarction had a better success rate than anterior wall myocardial infarctions and was statistically significant. 10. Those who are having short window period had a better success rate after thrombolysis. Shorter the window period higher the success rate

Electronic Payment Systems Influence In Retail Management System

Digital payment, often known as microelectronic compensation, is the process of transferring monetary value from one payment account to another using a digital device, such as a cell phone. An automatic compensation refers to a digital transaction that takes place between two parties.  The many forms of e-compensation include line and bank allocations, cards, mobile payments, and other methods.  Various factors can influence industries in determining the most effective type or types of automated payment systems for their merchants.   Numerical recompense facilities are platforms that facilitate transactions between two parties, the spender and the acceptor, using electronic means to exchange funds.   Electronic prices are increasing the accessibility of expenditure and financing.   Electronic payments are rapidly enhancing the efficiency of transactions.  The objective is to minimize the expenses and challenges associated with cash management, enhance the convenience of online transactions, and promote transparency in financial transactions between individuals.   The digital payment system is a significant factor in the rapidly expanding commercial landscape. The majority of organizations are actively engaging in digitalization.   The majority of significant company operations and transactions have transitioned into the era of digitalization.   The key objective of research is to analyses different modes of electronic payment systems, identify the factors influencing the adoption of robotic expense systems in retail operations, investigate the implementation and components of electronic payment in the city of Chennai, and assess the practices and preferences of respondents regarding payment methods, as well as the impact of electronic payment on retail operations.   The results indicate that electronic payment methods are beneficial for retail businesses

BIODEGRADATION OF TOLUENE HYDROCARBON BY A PSEUDOMONAS SP. ISOLATED FROM GASOLINE CONTAMINATED SOIL

ABSTRACT: In the present study efforts were made to isolate and characterize bacteria capable of aerobic biodegradation of toluene hydrocarbon from gasoline polluted soil. After initial screening, 28 different strains were isolated from soil samples and the most promising strain was selected for toluene degradation study. Biochemical and morphological characterization classified the bacterial strains selected as Pseudomonas sp. and was designated Pseudomonas sp. SBCT-17. The spectrophotometric determination of toluene monoxygenase activity, using horseradish preoxydase (HRP) assay showed 0.248 U/ml enzyme activity at 420 nm. The results obtained from enzyme assay and FT-IR degradation analysis in this study confirms that the Pseudomonas sp. SBCT-17 is an efficient strain capable of biodegrading toluene hydrocarbon

Roundness error measurement using teaching learning based optimization algorithm and comparison with particle swarm optimization algorithm

Form deviation of machined components need to be controlled within the required tolerance values for proper assembly and to serve the intended functional requirements. Methods like minimum zone circle (MZC) method, minimum circumscribed circle (MCC) method, maximum inscribed circle (MIC) method and least square circle (LSC) method are used to evaluate roundness error. Roundness error evaluation includes collection of co-ordinate points on the surface of the compo-nent and measurement using any of the above methods. Since, manual measurement of roundness error from these coordinate points is time consuming and less accurate, use of algorithms is highly appreciated. A detailed study of various optimization techniques showed that all evolutionary and swarm intelligence-based optimization algorithms require common control parameters and algorithm specific parameters. Improper tuning of these parameters either increases the computational effort or results in local optimal solution. Teaching Learning Based Optimization (TLBO) algorithm is used in this work as it does not require any algorithm specific parameters for the evaluation of roundness error. The results obtained are then compared with the results of Particle Swarm Optimization (PSO) algorithm to know the merits and demerits of both the algorithms when used for form measurement

The use of tools of data mining to decision making in engineering education—A systematic mapping study

In recent years, there has been an increasing amount of theoretical and applied research that has focused on educational data mining. The learning analytics is a discipline that uses techniques, methods, and algorithms that allow the user to discover and extract patterns in stored educational data, with the purpose of improving the teaching‐learning process. However, there are many requirements related to the use of new technologies in teaching‐learning processes that are practically unaddressed from the learning analytics. In an analysis of the literature, the existence of a systematic revision of the application of learning analytics in the field of engineering education is not evident. The study described in this article provides researchers with an overview of the progress made to date and identifies areas in which research is missing. To this end, a systematic mapping study has been carried out, oriented toward the classification of publications that focus on the type of research and the type of contribution. The results show a trend toward case study research that is mainly directed at software and computer science engineering. Furthermore, trends in the application of learning analytics are highlighted in the topics, such as student retention or dropout prediction, analysis of academic student data, student learning assessment and student behavior analysis. Although this systematic mapping study has focused on the application of learning analytics in engineering education, some of the results can also be applied to other educational areas

Radiogenomic Mapping of Edema/Cellular Invasion MRI-Phenotypes in Glioblastoma Multiforme

Despite recent discoveries of new molecular targets and pathways, the search for an effective therapy for Glioblastoma Multiforme (GBM) continues. A newly emerged field, radiogenomics, links gene expression profiles with MRI phenotypes. MRI-FLAIR is a noninvasive diagnostic modality and was previously found to correlate with cellular invasion in GBM. Thus, our radiogenomic screen has the potential to reveal novel molecular determinants of invasion. Here, we present the first comprehensive radiogenomic analysis using quantitative MRI volumetrics and large-scale gene- and microRNA expression profiling in GBM.Based on The Cancer Genome Atlas (TCGA), discovery and validation sets with gene, microRNA, and quantitative MR-imaging data were created. Top concordant genes and microRNAs correlated with high FLAIR volumes from both sets were further characterized by Kaplan Meier survival statistics, microRNA-gene correlation analyses, and GBM molecular subtype-specific distribution.The top upregulated gene in both the discovery (4 fold) and validation (11 fold) sets was PERIOSTIN (POSTN). The top downregulated microRNA in both sets was miR-219, which is predicted to bind to POSTN. Kaplan Meier analysis demonstrated that above median expression of POSTN resulted in significantly decreased survival and shorter time to disease progression (P<0.001). High POSTN and low miR-219 expression were significantly associated with the mesenchymal GBM subtype (P<0.0001).Here, we propose a novel diagnostic method to screen for molecular cancer subtypes and genomic correlates of cellular invasion. Our findings also have potential therapeutic significance since successful molecular inhibition of invasion will improve therapy and patient survival in GBM

An Antagomir to MicroRNA Let7f Promotes Neuroprotection in an Ischemic Stroke Model

We previously showed that middle-aged female rats sustain a larger infarct following experimental stroke as compared to younger female rats, and paradoxically, estrogen treatment to the older group is neurotoxic. Plasma and brain insulin-like growth factor-1 (IGF-1) levels decrease with age. However, IGF-1 infusion following stroke, prevents estrogen neurotoxicity in middle-aged female rats. IGF1 is neuroprotective and well tolerated, but also has potentially undesirable side effects. We hypothesized that microRNAs (miRNAs) that target the IGF-1 signaling family for translation repression could be alternatively suppressed to promote IGF-1-like neuroprotection. Here, we report that two conserved IGF pathway regulatory microRNAs, Let7f and miR1, can be inhibited to mimic and even extend the neuroprotection afforded by IGF-1. Anti-mir1 treatment, as late as 4 hours following ischemia, significantly reduced cortical infarct volume in adult female rats, while anti-Let7 robustly reduced both cortical and striatal infarcts, and preserved sensorimotor function and interhemispheric neural integration. No neuroprotection was observed in animals treated with a brain specific miRNA unrelated to IGF-1 (anti-miR124). Remarkably, anti-Let7f was only effective in intact females but not males or ovariectomized females indicating that the gonadal steroid environment critically modifies miRNA action. Let7f is preferentially expressed in microglia in the ischemic hemisphere and confirmed in ex vivo cultures of microglia obtained from the cortex. While IGF-1 was undetectable in microglia harvested from the non-ischemic hemisphere, IGF-1 was expressed by microglia obtained from the ischemic cortex and was further elevated by anti-Let7f treatment. Collectively these data support a novel miRNA-based therapeutic strategy for neuroprotection following stroke

ICAR: endoscopic skull‐base surgery

n/