310 research outputs found
Cellular Interactions in the Pathogenesis of Rheumatoid Arthritis: Cross-Talk Between T Cells and Fibroblast-Like Synoviocytes.
Rheumatoid arthritis is a debilitating systemic autoimmune disease with the most prominent clinical pathology appearing as joint disfigurement. Microscopically, an intense inflammatory reaction characterized by numerous joint invading leukocytes and aberrant expression of cytokines promotes cartilage degradation and joint space remodeling by resident fibroblast-like synoviocytes (FLS). In this context, continued research must be done to better understand how the most numerous invading lymphocyte, the T cell, interacts with the FLS. Previous work has shown that bidirectional signaling between these two cell types results in mutual stimulation and activation. However, a complete understanding of the mechanisms and consequences of T cell-FLS interaction has not yet been realized.
To better elucidate this interaction, various in vitro models were employed in this thesis. Classic T cell interactions involve the presentation of antigen; consequently, the capacity of FLS to function as antigen presenting cells (APC) for arthritogenic autoantigens was assessed. Indeed, FLS could function as APC and activate T cells through presentation of autoantigens. Turning towards T cell activation of FLS, cytokine activated T cells were employed which characteristics similar to T cells have found within rheumatoid arthritis synovial tissue. These cytokine activated T cells utilized membrane bound TNFα as a stimulatory molecule to induce secretion of inflammatory cytokines by FLS. Finally, the role of costimulation in the interaction of T cell and FLS was evaluated. FLS were found to express the costimulatory ligand B7-H3, which had differential effects (either activating or inhibitory) on T cells depending on the T cell’s activation state.
Hopefully these results combined will further the goal of a complete understanding of rheumatoid arthritis pathology and contribute towards development of novel treatments for this devastating disease.Ph.D.ImmunologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/58516/1/tranc_1.pd
Black-box modeling of nonlinear system using evolutionary neural NARX model
Nonlinear systems with uncertainty and disturbance are very difficult to model using mathematic approach. Therefore, a black-box modeling approach without any prior knowledge is necessary. There are some modeling approaches have been used to develop a black box model such as fuzzy logic, neural network, and evolution algorithms. In this paper, an evolutionary neural network by combining a neural network and a modified differential evolution algorithm is applied to model a nonlinear system. The feasibility and effectiveness of the proposed modeling are tested on a piezoelectric actuator SISO system and an experimental quadruple tank MIMO system
3PL provider selection in oil and gas industry using the analytic hierarchy process: A case study in oil-field services company X
This study aims to: (1) Summarize the criteria for selecting 3PL Provider in supply chain management from literature review and apply these criteria to build the criteria model in choosing 3PL Provider for oilfield services company X for the purpose of expanding their market in the oil and gas industry and (2) Analyze, evaluate two 3PL Providers, along with a new 3PL Provider and suggest the strategy for selecting the suitable 3PL Provider to meet the specific requirements from company X.
By arranging in-depth interviews with ten people with different positions, including Operation Manager, Supply Chain Manager, Logistics Manager, Base Manager and Logistics Specialist, along with AHP approach and expert choice 11.0 software support in collecting, processing and synthesizing data to evaluate and determine the appropriate 3 PL Provider for company X. In this study, three 3PL Providers have been chosen for analyzing and evaluating – 3PL Providers A, B, and C. The final results demonstrate that there are six main criteria and 13 sub-criteria in choosing 3PL Provider for oilfield services company X. The six main criteria are Performance, Price, Services, Quality assurance, IT system and Intangible values. The results and hypothetical situations have also been presented and discussed again with the expert logistics group to get their feedback about the practicability of the built model. The expert logistics group has agreed that the built criteria model and results are appropriate and adequate for evaluating and selecting a suitable 3PL Provider from the company’s specific demands. Consequently, this study can also be applied for similar purposes in other companies and shipping agents who need to work with outsourcing logistics services in oil and gas industry by using this built criteria model and synthesis results to find out the right decision for selecting 3PL Provider
Monitoring of Landslides in Mountainous Regions based on FEM Modelling and Rain Gauge Measurements
Vietnam is a country heavily influenced by climate change. The effect of climate change leads to a series of dangerous phenomena, such as landslides. Landslides occur not only in the mountainous province, but also in Delta provinces, where hundreds of landslides are reported annually in the North-Western provinces of Vietnam. These events have catastrophic impact to the community as well as the economy. In mountainous areas, the conditions for landslides to occur are met frequently, especially after heavy rains or geological activity, causing harm to the community as well as damaging or destroying much needed infrastructure and key transport routes. However, in Vietnam, investment in mountainous regions has been often lower than in urban areas. The meteorology monitoring and forecasting systems are ill equipped and overloaded, so they cannot deliver earlier and more accurate forecasts for complex weather events, unable to provide timely warnings. It can be seen that in countries that landslide often occur, researchers have been trying to develop low cost and efficient landslide detection system. This paper precisely addressed the problems mentioned, by designing and implementing an efficient and reliable Landslide Monitoring and Early Warning (LMnE) system based on the 3G/2G mobile communication system, and a rain gauge at the field site along with a carefully FEM (finite element method) simulation using the rain density information on the server. The system uses advanced processing algorithms combining obtained data at the central station
Wireless Technology for Monitoring Site-specific Landslide in Vietnam
Climate change has caused an increasing number of landslides, especially in the mountainous provinces of Vietnam, resulting in the destruction of vital transport and other infrastructure. Current monitoring and forecasting systems of the meteorology department cannot deliver accurate and reliable forecasts for weather events and issue timely warnings. This paper describes the development of a simple, low cost, and efficient system for monitoring and warning landslide in real-time. The authors focus on the use of wireless and related technologies in the implementation of a technical solution and some of the problems of the wireless sensor network (WSN) related to power consumption. Promising compressed sensing (CS) based solution for landslide monitoring is discussed and evaluated in the paper
ADSORPTION OF MERCURIC ION FROM AQUEOUS SOLUTIONS USING MODIFIED FLY ASH
In this study, fly ash was treated with NaOH solution (FAN) before modifying with (3-mercaptopropyl) triethoxysilane - MPTMS (FAMPS). By using FTIR, FESEM, XRD, EDX, and BET techniques, the change in structure, composition and morphology of FAN and FAMPS was evaluated. The FTIR spectra of FAN and FAMPS showed that there is no chemical reaction between the MPTMS and FAN. After modification, the FAMPS has a rough surface with composition difference from the FAN. Mercuric ion adsorption behavior as well as adsorptionisotherm models (Langmuir and Freundlich) of the FAN and FAMPS were also investigated and discussed. Thanks to FAN modification, the mercuric ion removal percent of the FAMPS was higher than that of the FAN. Owing to the adsorption data, Freundlich isotherm modelwas fitted for the mercuric ion adsorption process
Using fly ash treated by NaOH and H2SO4 solutions for Hg2+ and Cd2+ ion adsorption.
This paper presents the results of adsorption ability of heavy metal ions (Hg2+ and Cd2+) by fly ash (FA) before and after treatment using NaOH and H2SO4 solutions. Original- and treated FA were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM). Specific surface area of FA before and after treatment was calculated by Brunauer – Emmett – Teller (BET) isotherm equation. The obtained results indicated that the morphology and specific surface area of FA changed clearly after treatment by acid or alkaline solutions. Adsorption capacity the Hg2+ and Cd2+ ion by FA was determined from data of UV-Vis spectra. After treatment, the adsorption capacity of ions by FA increased remarkably in comparison with non-treated FA. The FA treated by NaOH solution has the adsorption capacity higher than FA treated by H2SO4 solution. The maximum adsorption capacity of the FA treated by NaOH solution for Cd2+ and Hg2+ ions at room temperature is 28.97 and 14.60 mg/g, respectively. The equilibrium adsorption data were described by the Langmuir and Freundlich isotherm models. The results showed that equilibrium data were fitted well to the Langmuir isotherm. Keywords. Fly ash, treatment, adsorption capacity, heavy metal, Langmuir isotherm
Distinct Molecular Effects of Angiotensin II and Angiotensin III in Rat Astrocytes
It is postulated that central effects of angiotensin (Ang) II may be indirect due to rapid conversion to Ang III by aminopeptidase A (APA). Previously, we showed that Ang II and Ang III induced mitogen-activated protein (MAP) kinases ERK1/2 and stress-activated protein kinase/Jun-terminal kinases (SAPK/JNK) phosphorylation in cultured rat astrocytes. Most importantly, both peptides were equipotent in causing phosphorylation of these MAP kinases. In these studies, we used brainstem and cerebellum astrocytes to determine whether Ang II’s phosphorylation of these MAP kinases is due to the conversion of the peptide to Ang III. We pretreated astrocytes with 10 μM amastatin A or 100 μM glutamate phosphonate, selective APA inhibitors, prior to stimulating with either Ang II or Ang III. Both peptides were equipotent in stimulating ERK1/2 and SAPK/JNK phosphorylation. The APA inhibitors failed to prevent Ang II- and Ang III-mediated phosphorylation of the MAP kinases. Further, pretreatment of astrocytes with the APA inhibitors did not affect Ang II- or Ang III-induced astrocyte growth. These findings suggest that both peptides directly induce phosphorylation of these MAP kinases as well as induce astrocyte growth. These studies establish both peptides as biologically active with similar intracellular and physiological effects
Classification of cow’s behaviors based on 3-DoF accelerations from cow’s movements
Cow’s behavior classification helps people to monitor cow activities, thus the health and physiological periods of cows can be well tracked. To classify the behavior of cows, the data from the 3-axis acceleration sensor mounted on their neck is often used. Data acquisition and preprocessing of sensor data is required in this device. We acquire data from the 3-axis acceleration sensor mounted on the cows’neck and send to the microcontrollter. At the microcontroller, a proposed decision tree is applied in real-time manner to classify four important activities of the cows (standing, lying, feeding, and walking). Finally, the results can be sent to the server through the wireless transmission module. The test results confirm the reliability of the proposed device
EFFECT OF SOME ADDITIVES ON PROCESSBILITY, MECHANICAL PROPERTIES AND MORPHOLOGY OF POLYOXYMETHYLENE/SILICA NANOCOMPOSITES
Using additives for polyoxymethylene/silica (POM/SiO2) nanocomposite system is one of suitable solutions to improve processbility, mechanical properties, especially, elongation at break of the material. In this paper, the effect of some additives on the processbility, mechanical properties and morphology of polyoxymethylene/silica (POM/SiO2) nanocomposite was investigated. Zinc stearate (under the commercial name ultraflow – UTF), ethylene-vinyl acetate copolymer (EVA), linear low density polyethylene (LLDPE) and polylactic acid grafted 5 wt.% of polyethylene glycol (PELA) were used as additives for the nanocomposites. The obtained results showed that the preparing process of the POM/SiO2 nanocomposite becam more easily in the presence of PELA, UTF and EVA, corresponding to a lower torque and mixing energy. The PELA caused decrease in the E-modulus or hardness and increase in elongation at break as well as tensile strength of the POM/SiO2 nanocomposites. The SEM images showed that POM and nanosilica were less compatible in the nanocomposite using EVA, LLDPE and UTF and they were more compatible with using PELA
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