611 research outputs found

    A study on Poynting effect in brain white matter: A hyperelastic 3D micromechanical model

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    A novel 3D micromechanical Finite Element Model (FEM) has been developed to depict the Poynting effect in bi-phasic Representative volume element (RVE) with axons embedded in surrounding extra-cellular matrix (ECM) for simulating the brain white matter response under simple and pure shear. In the proposed 3D FEM, nonlinear Ogden hyper-elastic material model describes axons and ECM materials. The modeled bi-phasic RVEs have axons tied to surrounding matrix. In this proof-of-concept (POC) FEM, three simple shear loading configurations and a pure shear scenario were simulated. Root mean square deviation (RMSD) were computed for stress and deformation response plots to depict role of axon-ECM orientations & loading condition on the Poynting effect. Variations in normal stresses (S11, S22, or S33) perpendicular to the shear plane emphasized role of fiber-matrix interactions. At high strains, the stress-strain% plots also indicated modest strain stiffening effects and bending stresses in purely sheared axons

    Study of Electrical, Optical and Structural Properties of Al- Doped ZnO Thin Films on PEN Substrates

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    Aluminum-doped zinc oxide (AZO), as one of the most promising transparent conducting oxide (TCO) material, has now been widely used in thin film solar cells. Most of the study of AZO films till date has been done on glass substrates but nowadays there is a growing interest in replacing glass with polymer substrate for the thin-film solar cell technology and many other flexible optoelectronic devices. In this study, AZO thin films were deposited at room temperature by RF magnetron sputtering on flexible substrates from a 3 inch diameter target of 2 wt % Al2O3 in zinc oxide. The effect of RF power on the structural, optical and electrical properties of AZO films was investigated by X-ray Diffraction (XRD), Hall measurement, and UV-visible spectrophotometery. The XRD data indicates a preferential c-axis orientation for all the films. All films exhibit high transmittance ( 85%) in visible region. Films deposited at 60 W power exhibit lowest resistivity of 1.2 10 – 3 Ωcm. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3102

    ON THE INTERPLAY BETWEEN BRAIN-COMPUTER INTERFACES AND MACHINE LEARNING ALGORITHMS: A SYSTEMS PERSPECTIVE

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    Today, computer algorithms use traditional human-computer interfaces (e.g., keyboard, mouse, gestures, etc.), to interact with and extend human capabilities across all knowledge domains, allowing them to make complex decisions underpinned by massive datasets and machine learning. Machine learning has seen remarkable success in the past decade in obtaining deep insights and recognizing unknown patterns in complex data sets, in part by emulating how the brain performs certain computations. As we increase our understanding of the human brain, brain-computer interfaces can benefit from the power of machine learning, both as an underlying model of how the brain performs computations and as a tool for processing high-dimensional brain recordings. The technology (machine learning) has come full circle and is being applied back to understanding the brain and any electric residues of the brain activity over the scalp (EEG). Similarly, domains such as natural language processing, machine translation, and scene understanding remain beyond the scope of true machine learning algorithms and require human participation to be solved. In this work, we investigate the interplay between brain-computer interfaces and machine learning through the lens of end-user usability. Specifically, we propose the systems and algorithms to enable synergistic and user-friendly integration between computers (machine learning) and the human brain (brain-computer interfaces). In this context, we provide our research contributions in two interrelated aspects by, (i) applying machine learning to solve challenges with EEG-based BCIs, and (ii) enabling human-assisted machine learning with EEG-based human input and implicit feedback.Ph.D

    The Effect of Expected Benefit and Perceived Cost on Employees’ Knowledge Sharing Behavior: a Study of It Employees in India

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    In the increasingly turbulent business environment knowledge is considered to be the most important source of sustainable competitive advantage and to sustain it, an organization must create, share, and utilize the knowledge it possesses.  The critical knowledge is only available to the organization as long as employees are willing to cooperate. It can easily be lost if the employees decide to explore other opportunities outside the organization or employees fear to share knowledge with co-workers.  To achieve continuous growth, organizations need to understand the factors which motivate and de-motivate the employees to share knowledge. The present study examines the impact of employees’ perception of perceived benefits and cost of knowledge sharing on their knowledge sharing behavior. Data were collected from 228 employees of two major Information Technology organizations in India. The results of regression analysis showed that benefits mainly perceived increase in expected association with others and expected contribution to organization positively influences employees’ knowledge sharing behaviour. Perceived cost was found to influence negatively on knowledge sharing behaviour. The findings of the study are expected to provide significant inputs to organizations to design the practices which make knowledge sharing an integral part of the day-to-day conversation.  &nbsp

    Modified dual osteotomy for Madelung’s deformity

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    Madelung’s deformity is one of the rare congenital deformities of the forearm and wrist, typically seen as positive ulnar variance and increased volar tilt due to the “Vickers” ligament. Different corrective surgical methods for this have been done in the literature. In this case of a 9-year-old Madelung’s like deformity, we have performed a modified dual osteotomy with periosteal preservation allowing natural articulation and bone to be modified, especially in a younger child. This article gives the surgical option to orthopedics for the future, especially in a younger child with severe deformity. This is a level V evidence-based therapeutic study

    PRE-ANALYTICAL VARIABLES IN CLINICAL CHEMISTRY: TRAINING MEDICAL UNDERGRADUATES THROUGH CASE BASED DISCUSSION

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    Background: Pre-analytical variables in clinical chemistry are factors prior to the biochemical analysis of samples affecting laboratory test results accounting for 32-75% of errors leading to misdiagnosis, decreased quality of medical care services and wastage of monetary resources. Aim: To educate first year medical undergraduates about pre-analytical variables through case based discussion and lecture method of teaching and assess the gain in knowledge by these methods. Methods and material: Two batches of medical students namely A (N=50) and B (N=52) were assessed for their background knowledge on the topic using an MCQ based questionnaire (pre-test). Batch A and B were taught through didactic lecture and case based discussion respectively. Post-test questionnaire was conducted to test the gain in knowledge of both batches. Delayed post-test was conducted after 2 weeks to assess retention of knowledge amongst students. Results: Pre-test scores of Batch A and B were not significantly different indicating that both batches had similar background knowledge of topic. Post-test scores vs. pre-test scores were significantly higher in both batches implying that both batches benefitted from their respective teaching sessions. But post-test score of Batch B was significantly higher than that of Batch A indicating higher gain of knowledge through case based discussion. Delayed post-test score was also significantly higher in Batch B vs. A implying better retention of knowledge through case based discussions. Conclusion: Topic ˜Pre-analytical variables in clinical chemistry must be included in undergraduate medical curriculum. Case based discussion could be an effective module for teaching the same. Key words: Case based discussion; Didactic lecture; Medical students; Medical education; Pre-analytical variables

    Assessing the factors that influence a recurrence of congenital talipes equinovarus in children treated with the Ponseti method

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    Background: Congenital talipes equinovarus, also known as clubfoot, is one of the most common congenital malformations in pediatric orthopedics. With a checkered treatment history extending from Hippocrates' bandages to Kite's serial plaster cast application to surgical treatment, no single modality can claim to be a complete treatment. Methods: In a combined prospective and retrospective study at the Department of Orthopaedics of St. Stephen's Hospital, 192 patients with 292 clubfeet who met the inclusion criteria and received ethics committee approval were included. The purpose of the research was to identify early recurrence characteristics, undertake the Pirani scoring, and identify additional clinical characteristics to evaluate recurrence predictors. Results: In our study, out of 192 patients, 188 were successfully treated with the Ponseti casting technique combined with tendoachilles tenotomy; tenotomy was required in 177 patients (93%). Four patients were lost to follow-up. Nine out of sixty-one children in the six-month-to-one-year age group showed the maximum rate of recurrence (15%). The mean number of cast applications was 7.23. In all, 90% of children required casts ranging from four to eight in number. The syndromic association was seen in 10.4% of cases with club feet. Most common among them were neural tube defects (4.2%) and arthrogryposis (3% of cases). Fourteen out of 154 (or 9%) of the non-operated idiopathic patients had lateral border recurrence during an average follow-up of two years. According to the Pirani score, recurrence was seen in eight out of twenty (or 40% of) syndromic patients and five out of fourteen (or 35% of) operated cases. In 37% of recurrences, dynamic supination was observed. Conclusions: Even though Ponseti's approach to treating idiopathic clubfoot is widely regarded as the gold standard, recurrences are known to occur even in the best of circumstances. The most common cause of recurrence was poor brace compliance, with families citing a variety of reasons

    PRE-ANALYTICAL VARIABLES IN CLINICAL CHEMISTRY: TRAINING MEDICAL UNDERGRADUATES THROUGH CASE BASED DISCUSSION

    Get PDF
    Background: Pre-analytical variables in clinical chemistry are factors prior to the biochemical analysis of samples affecting laboratory test results accounting for 32-75% of errors leading to misdiagnosis, decreased quality of medical care services and wastage of monetary resources. Aim: To educate first year medical undergraduates about pre-analytical variables through case based discussion and lecture method of teaching and assess the gain in knowledge by these methods. Methods and material: Two batches of medical students namely A (N=50) and B (N=52) were assessed for their background knowledge on the topic using an MCQ based questionnaire (pre-test). Batch A and B were taught through didactic lecture and case based discussion respectively. Post-test questionnaire was conducted to test the gain in knowledge of both batches. Delayed post-test was conducted after 2 weeks to assess retention of knowledge amongst students. Results: Pre-test scores of Batch A and B were not significantly different indicating that both batches had similar background knowledge of topic. Post-test scores vs. pre-test scores were significantly higher in both batches implying that both batches benefitted from their respective teaching sessions. But post-test score of Batch B was significantly higher than that of Batch A indicating higher gain of knowledge through case based discussion. Delayed post-test score was also significantly higher in Batch B vs. A implying better retention of knowledge through case based discussions. Conclusion: Topic ˜Pre-analytical variables in clinical chemistry must be included in undergraduate medical curriculum. Case based discussion could be an effective module for teaching the same. Key words: Case based discussion; Didactic lecture; Medical students; Medical education; Pre-analytical variables
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