204 research outputs found
EFFECTIVENESS OF SEISMIC BEARINGS ON A TYPICAL ISOLATED TWO-COLUMN RC BRIDGE PIER LOCATED IN NORTH MISSISSIPPI
The 2020 ASCE infrastructure report card has assigned a letter grade of D- for bridges in Mississippi based on poor to fair condition ratings with many approaching the end of their useful service lives. Bridges in northern Mississippi lie up to 100 miles from the New Madrid Fault and fall into the Region 3 Seismic Performance Category defined by AASHTO. The primary objective of this study is to evaluate the performance of commercially available bridge bearings on a common bridge pier type used in northern MS under the combined action of superstructure gravity and lateral seismic loads. The use of bearings as seismic isolation devices to limit the inelastic deformations in bridge substructures is a common practice in high seismic regions (Region 4) but their benefits in moderate ones (Region 3) have not been fully explored in MS. Analytical formulations under lateral load at the bearing levels are first used in the study to characterize modal characteristics and response of the bearing/pier subsystem idealized as a 2DOF oscillator. Effective linear properties of the bearing/pier system defined based on AASHTO provisions are used to determine expected overall behavior. Non-linear pushover analysis is then performed of an existing two-column pier recently designed to satisfy AASHTO criteria. The pier is modeled as a frame using beam and link elements available in a commercial finite element software (SAP2000). The analysis is used to capture the plastic hinge formation sequence, damage limit states in potential hinge locations, and the overall frame response up to the formation of a collapse mechanism. Lastly, non-linear time history analysis is performed using the software to obtain lateral deck/pier displacement histories in the transverse direction. The effectiveness of two common isolation bearings (laminated rubber and disc type) in isolating the pier from the deck motion and reducing the base shear is then demonstrated
Shiva: A Framework for Graph Based Ontology Matching
Since long, corporations are looking for knowledge sources which can provide
structured description of data and can focus on meaning and shared
understanding. Structures which can facilitate open world assumptions and can
be flexible enough to incorporate and recognize more than one name for an
entity. A source whose major purpose is to facilitate human communication and
interoperability. Clearly, databases fail to provide these features and
ontologies have emerged as an alternative choice, but corporations working on
same domain tend to make different ontologies. The problem occurs when they
want to share their data/knowledge. Thus we need tools to merge ontologies into
one. This task is termed as ontology matching. This is an emerging area and
still we have to go a long way in having an ideal matcher which can produce
good results. In this paper we have shown a framework to matching ontologies
using graphs
Review of Vortex Lattice Method for Supersonic Aircraft Design
© The Author(s), 2023. Published by Cambridge University Press on behalf of Royal Aeronautical Society. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (https://creativecommons.org/licenses/by/4.0/There has been a renewed interest in developing environmentally friendly, economically vi-able, and technologically feasible supersonic transport aircraft and reduced order modeling methods can play an important contribution in accelerating the design process of these future aircraft. This paper reviews the use of the vortex lattice method (VLM) in modeling the gen-eral aerodynamics of subsonic and supersonic aircraft. The historical overview of the vortex lattice method is reviewed which indicates the use of this method for over a century for devel-opment and advancements in the aerodynamic analysis of subsonic and supersonic aircraft. The preference of VLM over other potential flow-solvers is because of its low order highly efficient computational analysis which is quick and efficient. Developments in VLM covering steady, unsteady state, linear and non-linear aerodynamic characteristics for different wing planform for the purpose of several different types of design optimization is reviewed. For over a decade classical vortex lattice method has been used for multi-objective optimization studies for commercial aircraft and unmanned aerial vehicle’s aerodynamic performance op-timization. VLM was one of the major potential flow solvers for studying the aerodynamic and aeroelastic characteristics of many wings and aircraft for NASA’s supersonic transport mission (SST). VLM is a preferred means for solving large numbers of computational design parameters in less time, more efficiently, and cheaper when compared to conventional CFD analysis which lends itself more to detailed study and solving the more challenging configu-ration and aerodynamic features of civil supersonic transport.Peer reviewe
Efficient T cell migration and activation require L-plastin
Rapid re-organization of the actin cytoskeleton supports T-cell trafficking towards immune sites and interaction with antigen presenting cells (APCs). F-actin rearrangement enables T-cell trafficking by stabilizing adhesion to vascular endothelial cells and promoting transendothelial migration. T-cell/APC immune synapse (IS) maturation also relies upon f-actin-anchored LFA-1:ICAM-1 ligation. Therefore, efficient T-cell responses require tight regulation of f-actin dynamics. In this review, we summarize how the actin-bundling protein L-plastin (LPL) regulates T-cell activation and migration. LPL enhances f-actin polymerization and also directly binds to the β2 chain of the integrin LFA-1 to support intercellular adhesion and IS formation in human and murine T cells. LPL- deficient T cells migrate slowly in response to chemo-attractants such as CXCL12, CCL19, and poorly polarize towards ICAM-1. Loss of LPL impairs thymic egress and intranodal motility. LPL is also required for T-cell IS maturation with APCs, and therefore for efficient cytokine production and proliferation. LP
Lipid shell modified with combination of lipid and phospholipids in solid lipid nanoparticles for engineered specificity of paclitaxel in tumor bearing mice.
Paclitaxel (PTX) is an anticancer drug belonging to the class of Taxan. It is active against various types of carcinomas. The marketed formulation of paclitaxel is associated with deleterious effects with lack of specificity to tumor. Solid lipid nanoparticles (SLN) are colloidal carriers extensively studied and developed for there potential uses especially for controlled release and site specificity. The present study was designed to develop a formulation of PTX in the form of SLN to be administered via IV route with improved tumor specificity, in which the lipid shell was modified by using combination of lipid with phospholipids. Total eight formulations were prepared and were characterized by various in vitro and in vivo parameters. The microemulsification method was used for the preparation of SLN.The production yield of resulting process for all SLN was high. Average particle size was ranged between 209 nm to 385 nm. The developed PTX-SLN showed high percentage entrapment efficiency. The zeta potential values showed the good stable feature of the sln.The in vitro dissolution study showed that drug release was more retarded and was found to dependent on concentration of lipids employed. In vitro cytotoxicity study was performed on MCF-7 cancer cell line, which showed that formulation G2 is having more potentiating effect on cancer cell line. Tissue targeting study and tumor growth inhibition studies were performed on mice where the PTX loaded SLN from batch G2 shown more promising outcome. Results obtained from this study indicated strongly that developed SLN are having potential as an efficient drug delivery system for paclitaxel
Dysembryoplastic neuropithelial tumor: a rare case report
Dysembryoplastic neuropithelial tumor (DNET) is a rare recently described, benign glioneural tumor frequently associated with intractable seizures in children and young adults which is important to recognise clinically and radiologically as it is surgically curable without need for adjuvant chemoradiotherapy. We hereby present a case report of a 10year old male child who presented with intractable seizures and right parietal space occupying lesion which was diagnosed DNET radiologically, treated by microsurgical excision and confirmed histopathologically as DNET, thus emphasising multidisciplinary role in management of this rare entity
Determination of Shrinkage of Fine-Grained Soils using 3D Scanning Technology
Shrinkage Limit is the moisture content parameter in fine grained soil which is related to the volume stability of the soil. The conventional method, ASTM Standard D427-04 that uses mercury has been replaced by wax method, ASTM Standard D4943-02 that uses wax and water or MT-92 that uses spray coating. This modification has certainly minimized safety concerns of the laboratory technicians by avoiding the use of the health hazardous substance, mercury (Hg) but it is not really an economic and convenient method. This thesis proposes a 3D scanning method of determining the shrinkage limit of fine grained soils. The 3D scanning method involves the use of a calibrated 3D scanner to obtain the 3D model of soil samples and the CREO or the SOLIDWORKS software to determine the volume of the 3D model. The experimental and the statistical results demonstrate that values for Shrinkage Limit of soils calculated by Spray Coating Method and 3D Scanning Method can be thoroughly correlated
Haemostatic abnormalities in solid malignancies
Background: Though the actual symptoms of any haemostatic abnormalities in patients of solid malignancies are not seen commonly screening in all such cases can guide us to correct those abnormalities in time and improve the outcome. The present study is undertaken with an objective to find out coagulation disorders in patients of solid malignancies and compare their levels according to the stage of the cancer.Methods: A prospective study was undertaken in a tertiary care centre in Maharashtra, India from December 2010 to September 2012. Total 102 cases with malignancies diagnosed on histopathology/cytological examination were tested for BT, CT, Platelet count, PT, APTT, TT and D-dimer levels. These tests were repeated on first postoperative or post chemotherapy day wherever possible. Early and advanced stages of cancer were divided according to the spread of the tumor. Results were compared between the two. DIC cases were also noted.Results: Out of 102 cases studied, haemostatic abnormalities were more common in adenocarcinomas that too in mucin secreting adenocarcinomas. The percentage of cases with increased D-dimer values was higher in the advanced disease compared to early disease. The PT, APTT, TT and platelet count showed statistically significant differences between the early and advanced disease groups. Compared to preoperative values, postoperative values were abnormal but the change was not statistically significant.Conclusions: Screening for coagulation profile in all solid malignancies can help to predict the chances of complication and therapeutic interventions can be done
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