Multi-agent coalition formation in power transmission planning

Deregulation and restructuring have become unavoidable trends to the power industry recently in order to increase its efficiency, to reduce operation costs, or to provide customers better services. The once centralized system planning and management must be remodeled to reflect the changes in the market environment. We have proposed and developed a multi-agent based system to assist players, such as, owners of power generation stations, owners of transmission lines, and groups of consumers, in the same market to select partners to form coalitions. The system provides users with a cooperation plan and its associated cost allocation plan for the users to support their decision making process. Bilateral Shapley Value (BSV) was selected as the theoretical foundation to develop the system. The multi-agent system was developed by the combination of IDEAS and Tcl/Tk.published_or_final_versio

Differential protection against oxidative stress and nitric oxide overproduction in cardiovascular and pulmonary systems by propofol during endotoxemia

<p>Abstract</p> <p>Background</p> <p>Both overproduction of nitric oxide (NO) and oxidative injury of cardiovascular and pulmonary systems contribute to fatal cardiovascular depression during endotoxemia. We investigated in the present study the relative contribution of oxidative stress and NO to cardiovascular depression during different stages of endotoxemia, and delineated their roles in cardiovascular protective effects of a commonly used anesthetic propofol during endotoxemia.</p> <p>Methods</p> <p>Experimental endotoxemia was induced by systemic injection of <it>E. coli </it>lipopolysaccharide (LPS, 15 mg/kg) to Sprague-Dawley rats that were maintained under propofol (15 or 30 mg/kg/h, i.v.) anesthesia. Mean systemic arterial pressure (MSAP) and heart rate (HR) were monitored for 6 h after the endotoxin. Tissue level of NO was measured by chemical reduction-linked chemiluminescence and oxidative burst activity was determined using dihydroethidium method. Expression of NO synthase (NOS) was determined by immunoblotting. The Scheffé multiple range test was used for post hoc statistical analysis.</p> <p>Results</p> <p>Systemic injection of LPS (15 mg/kg) induced biphasic decreases in MSAP and HR. In the heart, lung and aorta, an abrupt increase in lipid peroxidation, our experimental index of oxidative tissue injury, was detected in early stage and sustained during late stage cardiovascular depression. LPS injection, on the other hand, induced a gradual increase in tissue nitrite and nitrate levels in the same organs that peaked during late stage endotoxemia. Propofol infusion (15 or 30 mg/kg/h, i.v.) significantly attenuated lipid peroxidation in the heart, lung and aorta during early and late stage endotoxemia. High dose (30 mg/kg/h, i.v.) propofol also reversed the LPS-induced inducible NO synthase (iNOS) upregulation and NO production in the aorta, alongside a significant amelioration of late stage cardiovascular depression and increase in survival time during endotoxemia.</p> <p>Conclusion</p> <p>Together these results suggest that oxidative injury and NO may play a differential role in LPS-induced cardiovascular depression. Oxidative tissue injury is associated with both early and late stage; whereas NO is engaged primarily in late stage cardiovascular depression. Moreover, propofol anesthesia may protect against fatal cardiovascular depression during endotoxemia by attenuating the late stage NO surge in the aorta, possibly via inhibition of iNOS upregulation by the endotoxin.</p

Effect of taurine on toxicity of oxidized cholesterol and oxidized fish oil in rats

[[abstract]]Taurine (2-aminoethanesulfonic acid) Occurs naturally in food, especially in seafood and meat. The aim of our investigation was to evaluate the effect of dietary taurine on oxidized cholesterol and oxidized fish oil induced toxicity in male Wistar rats. Thirty male wistar rats were fed with diets supplemented with 5% taurine, 2% oxidized cholesterol or 3% oxidized fish oil for 6 weeks. After feeding such diet, taurine could increase the high density lipoprotein-cholesterol (HDL-C) level in plasma, and glutathione (GSH) level in plasma, and decrease the activities of alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST) in plasma, and the levels of low density lipoprotein-cholesterol (LDL-C), very low density lipoprotein-cholesterol (VLDL-C), triglyceride, total cholesterol in plasma, and relative ratios of liver weight to body weight and thiobarbituric acid-reactive substances (TBARS.) level in the rat liver caused by oxidized cholesterol and oxidized fish oil. It could reduce the biochemical parameters characteristic in the plasma and rate liver caused by oxidized cholesterol and oxidized fish oil. It was also found that taurine possessed a good recovering effect and a short-term preventing effect from the toxicity of oxidized cholesterol and oxidized fish oil in rats. The results suggest that taurine may play an important role in suppressing effect by oxidized cholesterol and oxidized fish oil induced toxicity in rats

Dietary Caffeic Acid, Ferulic Acid and Coumaric Acid Supplements on Cholesterol Metabolism and Antioxidant Activity in Rats

[[abstract]]This study was designed to test the lipid-lowering and antioxidative activities of three phenolic compounds, caffeic acid, ferulic acid and coumaric acid. Four groups of rats were given a semisynthetic diet containing 3% of cholesterol for 6 weeks. The control group only received a high cholesterol diet, whereas the other three groups received a diet including 0.2% of caffeic acid, 0.2% of ferulic acid and 0.2% of coumaric acid. The caffeic acid, ferulic acid and coumaric acid significantly lowered the plasma lipid and hepatic cholesterol levels compared to those in the control (p < 0.05). The hepatic HMG-CoA reductase activity was significantly lower in the caffeic acid group than in the ferulic acid and coumaric acid groups (p < 0.05), while the hepatic ACAT activity was significantly lower in the caffeic acid, ferulic acid and coumaric acid groups compared to the control group (p < 0.05). The overall potential of the antioxidant system was significantly enhanced by the caffeic acid, ferulic acid and coumaric acid supplements as the plasma and hepatic TBARS levels were lowered while the hepatic SOD activities and GSH concentration were elevated in the high-cholesterol-fed rats (p < 0.05). Furthermore, these results indicated that the supplementation of caffeic acid, ferulic acid and coumaric acid boosted the antioxidant activity in rats and promoted the excretion of neutral sterol and acidic sterol (p < 0.05), thereby leading to a decreased absorption of dietary cholesterol as well as lower plasma, hepatic cholesterol and promoted excretion of fecal sterols

Short-term toxicity of aristolochic acid, aristolochic acid-I and aristolochic acid-II in rats

[[abstract]]We compared the short-term toxicity of toxic components of aristolochic acid in rats. Twenty-four female Wistar rats were divided into 4 groups and treated orally every 3-days with 10 mg/kg each of aristolochic acid, aristolochic acid-I and aristolochic acid-II for 19 days. After treatment, the relative ratio of liver and kidney weight to body weight, the concentrations of RBC, hemoglobin and hematocrit in the blood, the levels of aspartate amino transferase, alanine amino transferase, alkaline phosphatase, blood urea, nitrogen and creatinine in the plasma, and the levels of urinary urea nitrogen and creatinine in the urine were significantly increased. Body weight of rats and the levels of Na+, K+, Ca2+ in the urine were significantly decreased, especially for groups treated with aristolochic acid and aristolochic acid-II. Pathological examination of liver and kidney also showed cell enlargement and lesions, especially for groups treated with aristolochic acid and aristolochic acid-II. The aristolochic acid exhibited significant toxicity, and the short-term toxicity of aristolochic acid-II and aristolochic acid was similar to each other. Renal but not hepatic failure induced by aristolochic: acid could be prevented by pentoxifylline. (c) 2007 Elsevier Ltd. All rights reserved

Effect of taurine on toxicity of oxidized cholesterol in rats

[[abstract]]This research was aimed to study the effect of dietary taurine on the toxicity of oxidized cholesterol in male Wistar rats. The rats were divided into eight groups and fed different diets with or without supplement of 5% taurine and 3% oxidized cholesterol for 8 weeks. To evaluate effects of taurine at the same time, before diets and after diets in the food, after feeding diet with 3% oxidized cholesterol and 5% taurine at the same time, taurine could improve the decrease of body weight and the glutathione (GSH) level in the liver, and the increase of relative ratio of liver or kidney weight to body weight and thiobarbituric acid-reactive substances (TBARS) level in the liver of rats caused by oxidized cholesterol (P < 0.05). It also could inhibit the activities of aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) in the plasma of rats caused by oxidized cholesterol (P < 0.05). It was also found that taurine possessed a good recovering effect and a short-term preventing effect the toxicity of oxidized cholesterol in rats. Judging from these data, on taurine may play an important role in diminishing the toxic effect of oxidized cholesterol in rats

Comparing factors affecting commencement and cessation of betel quid chewing behavior in Taiwanese adults

<p>Abstract</p> <p>Background</p> <p>Betel quid is the fourth most common used substance in the world after tobacco, alcohol and caffeine. Although factors related to betel quid chewing or cessation of behaviors were reported previously, few studies simultaneously compared both behaviors in the same population. In addition, it is essential to consider time-to-event concept, since the chance of developing or stopping habit may vary over time. The purpose of this study was to compare the risk factors for commencement and cessation of betel quid chewing behaviors in a time-to-event setting.</p> <p>Methods</p> <p>A stratified multi-stage cluster sampling with selection probabilities proportional to size (PPS) was designed for Taiwanese adults with aged 18 years old and above. Kaplan-Meier estimates and Cox proportional hazard regression models were used to compare and calculate the hazard rate ratios for related factors to commencement or cessation of chewing habits.</p> <p>Results</p> <p>In Taiwan, men had a higher betel quid chewing rate (M: 20.9%, W: 1.2%), but woman chewers had a lower cessation rate (M: 27.5%, W: 12.7%). The hazard rate ratio (HRR) of having chewing habit changed from 4.22 (men vs women) univariately to 1.38 multivariablely, which indicated gender differences were confounded by other factors. In multivariable analysis, the risk factors of gender, education and ethnicity were significantly associated with both starting and cessation of betel quid chewing behavior. The factors of occupation, cigarette smoking and alcohol drinking were only associated with starting habit.</p> <p>Conclusion</p> <p>Commencement or cessation of chewing behavior involves a scenario of time, hence it is preferable to use a time-to-event approach for the comparison. The cessation rates of betel quid chewing were decreasingly associated with the daily consumption of betel quid. Hence, reducing of daily amount in betel quid cessation program may be associated with future stopping habit.</p

Numerical simulation of blood flow and pressure drop in the pulmonary arterial and venous circulation

A novel multiscale mathematical and computational model of the pulmonary circulation is presented and used to analyse both arterial and venous pressure and flow. This work is a major advance over previous studies by Olufsen et al. (Ann Biomed Eng 28:1281–1299, 2012) which only considered the arterial circulation. For the first three generations of vessels within the pulmonary circulation, geometry is specified from patient-specific measurements obtained using magnetic resonance imaging (MRI). Blood flow and pressure in the larger arteries and veins are predicted using a nonlinear, cross-sectional-area-averaged system of equations for a Newtonian fluid in an elastic tube. Inflow into the main pulmonary artery is obtained from MRI measurements, while pressure entering the left atrium from the main pulmonary vein is kept constant at the normal mean value of 2 mmHg. Each terminal vessel in the network of ‘large’ arteries is connected to its corresponding terminal vein via a network of vessels representing the vascular bed of smaller arteries and veins. We develop and implement an algorithm to calculate the admittance of each vascular bed, using bifurcating structured trees and recursion. The structured-tree models take into account the geometry and material properties of the ‘smaller’ arteries and veins of radii ≥ 50 μ m. We study the effects on flow and pressure associated with three classes of pulmonary hypertension expressed via stiffening of larger and smaller vessels, and vascular rarefaction. The results of simulating these pathological conditions are in agreement with clinical observations, showing that the model has potential for assisting with diagnosis and treatment for circulatory diseases within the lung

The Influences of H2Plasma Pretreatment on the Growth of Vertically Aligned Carbon Nanotubes by Microwave Plasma Chemical Vapor Deposition

The effects of H2flow rate during plasma pretreatment on synthesizing the multiwalled carbon nanotubes (MWCNTs) by using the microwave plasma chemical vapor deposition are investigated in this study. A H2and CH4gas mixture with a 9:1 ratio was used as a precursor for the synthesis of MWCNT on Ni-coated TaN/Si(100) substrates. The structure and composition of Ni catalyst nanoparticles were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The present findings showed that denser Ni catalyst nanoparticles and more vertically aligned MWCNTs could be effectively achieved at higher flow rates. From Raman results, we found that the intensity ratio of G and D bands (ID/IG) decreases with an increasing flow rate. In addition, TEM results suggest that H2plasma pretreatment can effectively reduce the amorphous carbon and carbonaceous particles. As a result, the pretreatment plays a crucial role in modifying the obtained MWCNTs structures

The need for nursing instruction in patients receiving steroid pulse therapy for the treatment of autoimmune diseases and the effect of instruction on patient knowledge

<p>Abstract</p> <p>Background</p> <p>Many patients who receive steroid pulse therapy go home the same day or the day after steroid administration. Nursing instructions are important for improving patient knowledge related to their diseases and treatments, but the short hospital stay often prevents complete education and guidance regarding the given therapy. The purpose of this study was to investigate the need for nursing instruction in patients receiving steroid pulse therapy for the treatment of autoimmune diseases and the effect of instruction on patient knowledge of their disease and treatment.</p> <p>Methods</p> <p>Patients with systemic lupus erythematosus (SLE) and systemic sclerosis receiving steroid pulse therapy (N = 63) were recruited from a medical center in Taipei. A structured questionnaire was used for data collection before and after nursing instruction, and 1 week as well as 2 weeks after therapy. The need for nursing instruction and knowledge levels were validated using Cronbach's α reliability test.</p> <p>Results</p> <p>There was a significant difference (<it>P </it>< 0.001) in the need for nursing instruction among the 4 time points. There was a positive correlation between the need for nursing instruction and body weight change, frequency of treatment, and distress, but there was a negative correlation with knowledge level (β = -0.012, <it>P </it>= 0.003) regarding symptoms. The knowledge level of subjects after nursing instruction was significantly higher than before nursing instruction (80 ± 14.31 vs. 70.06 ± 17.23, <it>P </it>< 0.001).</p> <p>Conclusions</p> <p>This study indicates that nursing instruction is needed by patients receiving steroid pulse therapy, and that by designing and administering nursing instructions according to the priority of patient symptoms, nurses can improve patient knowledge related to their diseases and treatments. In addition, the need for nursing instruction can be affected by patient characteristics.</p