Numerical Study about Effect of Different Boundary Conditions on Compressive Modulus Coefficient of Bonded and Non-Bonded Cylindrical Isolators

604-609Elastomers (Rubber and rubber-like materials) are widely utilized in many engineering applications due to their specific properties like high elasticity with good static and dynamic behaviors. Rubber blocks are one of the elastomeric components and it is employed in many applications such as vibration isolators, bumpers, shock absorbers, and dampers, etc. Most of the rubber blocks are cylindrical in shape and it can undergo large deformation under different loadings and contact conditions (fixed-fixed, friction-friction and fixed-friction). In this present work, experimentally validated Ogden hyper-elastic material model is adopted in the finite element analysis (FEA). The FE model is validated with other published experimental work. In addition, the following six boundary conditions namely BC1 (Fixed – Fixed), BC2 (Fixed – Friction), BC3 (Friction – Friction), BC4 (Fixed – Cap), BC5 (Cap – Friction) and BC6 (Cap – Cap) boundary conditions are taken for comparative study. The aspect ratio (radius/height) of the rubber isolator also varied as 0.5, 0.75, and 1. From the numerical analysis carried out, it is found that the BC6 (Cap–Cap) with aspect ratio 1 showed better compressive modulus coefficient over other parameters taken for study

Numerical Study about Effect of Different Boundary Conditions on Compressive Modulus Coefficient of Bonded and Non-Bonded Cylindrical Isolators

Elastomers (Rubber and rubber-like materials) are widely utilized in many engineering applications due to their specific properties like high elasticity with good static and dynamic behaviors. Rubber blocks are one of the elastomeric components and it is employed in many applications such as vibration isolators, bumpers, shock absorbers, and dampers, etc. Most of the rubber blocks are cylindrical in shape and it can undergo large deformation under different loadings and contact conditions (fixed-fixed, friction-friction and fixed-friction). In this present work, experimentally validated Ogden hyper-elastic material model is adopted in the finite element analysis (FEA). The FE model is validated with other published experimental work. In addition, the following six boundary conditions namely BC1 (Fixed – Fixed), BC2 (Fixed – Friction), BC3 (Friction – Friction), BC4 (Fixed – Cap), BC5 (Cap – Friction) and BC6 (Cap – Cap) boundary conditions are taken for comparative study. The aspect ratio (radius/height) of the rubber isolator also varied as 0.5, 0.75, and 1. From the numerical analysis carried out, it is found that the BC6 (Cap–Cap) with aspect ratio 1 showed better compressive modulus coefficient over other parameters taken for study

Functional Dichotomy between NKG2D and CD28-Mediated Co-Stimulation in Human CD8+ T Cells

Both CD28 and NKG2D can function as co-stimulatory receptors in human CD8+ T cells. However, their independent functional contributions in distinct CD8+ T cell subsets are not well understood. In this study, CD8+ T cells in human peripheral blood- and lung-derived lymphocytes were analyzed for CD28 and NKG2D expression and function. We found a higher level of CD28 expression in PBMC-derived naïve (CD45RA+CD27+) and memory (CD45RA−CD27+) CD8+ T cells (CD28Hi), while its expression was significantly lower in effector (CD45RA+CD27−) CD8+ T cells (CD28Lo). Irrespective of the differences in the CD28 levels, NKG2D expression was comparable in all three CD8+ T cell subsets. CD28 and NKG2D expressions followed similar patterns in human lung-resident GILGFVFTL/HLA-A2-pentamer positive CD8+ T cells. Co-stimulation of CD28Lo effector T cells via NKG2D significantly increased IFN-γ and TNF-α levels. On the contrary, irrespective of its comparable levels, NKG2D-mediated co-stimulation failed to augment IFN-γ and TNF-α production in CD28Hi naïve/memory T cells. Additionally, CD28-mediated co-stimulation was obligatory for IL-2 generation and thereby its production was limited only to the CD28Hi naïve/memory subsets. MICA, a ligand for NKG2D was abundantly expressed in the tracheal epithelial cells, validating the use of NKG2D as the major co-stimulatory receptor by tissue-resident CD8+ effector T cells. Based on these findings, we conclude that NKG2D may provide an expanded level of co-stimulation to tissue-residing effector CD8+ T cells. Thus, incorporation of co-stimulation via NKG2D in addition to CD28 is essential to activate tumor or tissue-infiltrating effector CD8+ T cells. However, boosting a recall immune response via memory CD8+ T cells or vaccination to stimulate naïve CD8+ T cells would require CD28-mediated co-stimulation

Conceptual Framework of Antecedents to Trends on Permanent Magnet Synchronous Generators for Wind Energy Conversion Systems

Wind Energy Conversion System (WECS) plays an inevitable role across the world. WECS consist of many components and equipment’s such as turbines, hub assembly, yaw mechanism, electrical machines; power electronics based power conditioning units, protection devices, rotor, blades, main shaft, gear-box, mainframe, transmission systems and etc. These machinery and devices technologies have been developed on gradually and steadily. The electrical machine used to convert mechanical rotational energy into electrical energy is the core of any WECS. Many electrical machines (generator) has been used in WECS, among the generators the Permanent Magnet Synchronous Generators (PMSGs) have gained special focus, been connected with wind farms to become the most desirable due to its enhanced efficiency in power conversion from wind energy turbine. This article provides a review of literatures and highlights the updates, progresses, and revolutionary trends observed in WECS-based PMSGs. The study also compares the geared and direct-driven conversion systems. Further, the classifications of electrical machines that are utilized in WECS are also discussed. The literature review covers the analysis of design aspects by taking various topologies of PMSGs into consideration. In the final sections, the PMSGs are reviewed and compared for further investigations. This review article predominantly emphasizes the conceptual framework that shed insights on the research challenges present in conducting the proposed works such as analysis, suitability, design, and control of PMSGs for WECS

Clinical Practice Guidelines (CPGs) for stroke rehabilitation from Low- and Middle-Income Countries (LMICs): Protocol for systematic review.

IntroductionStroke rehabilitation guidelines promoteclinical decision making, enhance quality of healthcare delivery, minimize healthcare costs, and identify gaps in current knowledge to guide future research. However, there are no published reviews that have exclusively evaluated the quality of existing Clinical Practice Guidelines (CPGs) for stroke rehabilitation from Low- and Middle-Income Countries (LMICs) or provided any insights into the cultural variation, adaptations, or gaps in implementation specific to LMICs.ObjectivesTo identify CPGs developed by LMICs for stroke rehabilitation and evaluate their quality using AGREE-II and AGREE-REX tool.MethodsThe review protocol is prepared in accordance with the PRISMA-P guidelines and the review was registered in PROSPERO (CRD42022382486). The search was run in Medline, EMBASE, CINHAL, PEDro for guidelines published between 2000 till July 2022. Additionally, SUMSearch, Google, and other guideline portals and gray literature were searched. The included studies were then subjected to data extraction for the following details: Study ID, title of the CPG, country of origin, characteristics of CPG (Scope-national/regional, level of care, multidisciplinary/uni-disciplinary), and information on stroke rehabilitation relevant recommendations. The quality of the included CPGs will be subsequently evaluated using AGREE-II and AGREE-REX tool.Results & conclusionThis systematic review aims to explore the gaps in existing CPGs specific to LMICs and will aid in development/adaptation/contextualization of CPGs for implementation in LMICs