Distinct Fatty Acid Compositions of HDL Phospholipids Are Characteristic of Metabolic Syndrome and Premature Coronary Heart Disease—Family Study

HDL particles can be structurally modified in atherosclerotic disorders associated with low HDL cholesterol level (HDL-C). We studied whether the lipidome of the main phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and sphingomyelin (SM) species of HDL2 and HDL3 subfractions is associated with premature coronary heart disease (CHD) or metabolic syndrome (MetS) in families where common low HDL-C predisposes to premature CHD. The lipidome was analyzed by LC-MS. Lysophosphatidylcholines were depleted of linoleic acid relative to more saturated and shorter-chained acids containing species in MetS compared with non-affected subjects: the ratio of palmitic to linoleic acid was elevated by more than 30%. A minor PC (16:0/16:1) was elevated (28–40%) in MetS. The contents of oleic acid containing PCs were elevated relative to linoleic acid containing PCs in MetS; the ratio of PC (16:0/18:1) to PC (16:0/18:2) was elevated by 11–16%. Certain PC and SM ratios, e.g., PC (18:0/20:3) to PC (16:0/18:2) and a minor SM 36:2 to an abundant SM 34:1, were higher (11–36%) in MetS and CHD. The fatty acid composition of certain LPCs and PCs displayed a characteristic pattern in MetS, enriched with palmitic, palmitoleic or oleic acids relative to linoleic acid. Certain PC and SM ratios related consistently to CHD and MetS.     

Preparation and Study of Pd Catalysts Supported on Activated Carbon Cloth (ACC) for Direct Synthesis of H2O2 from H2 and O2

Activated carbon cloths (ACCs) were used as supports for Pd catalysts. The catalyst preparation was carried out by the impregnation method using acidic solution of palladium dichloride (PdCl₂) as metal precursor. The effects of the oxidation state of the loaded metal, heat treatment of the catalysts in different atmosphere (H₂, air) at different temperatures and surface chemistry of the support on the catalyst characterizations and the catalytic activities were investigated. Wet oxidation of ACC was done by nitric acid in order to induce oxygen-containing surface functional groups. Surface chemistry of the support and oxidation state of the metallic phase was investigated by means of XPS, TPD, SEM, DTA and TGA tests. Direct synthesis of hydrogen peroxide from H₂ and O₂ was performed batch wise in a stainless steel autoclave. The reactions were conducted under high pressure (38 bar) at 0 °C and methanol was used as reaction medium. The direct synthesis results showed that the oxygen-containing surface functional groups increase the selectivity of the catalysts by reducing the rate of water production. Existence of the oxidized state of Pd (PdO) also makes the catalyst more selective than the corresponding zerovalent state (Pd0). PdO affected on selectivity by increasing the rate of H₂O₂ production and reducing the amount of production of water, simultaneously.     

Postpartum Weight Retention is Associated with Elevated Ratio of Oxidized LDL Lipids to HDL-Cholesterol

Oxidized LDL lipids (ox‐LDL) are associated with lifestyle diseases such as cardiovascular diseases, metabolic syndrome and type 2 diabetes. The present study investigated how postpartum weight retention effects on ox‐LDL and serum lipids. The study is a nested comparative research of a cluster‐randomized controlled trial, NELLI (lifestyle and counselling during pregnancy). During early pregnancy (8–12 weeks) and 1 year postpartum, 141 women participated in measurements for determining of plasma lipids: total cholesterol (T‐C), LDL‐cholesterol (LDL‐C), HDL‐cholesterol (HDL‐C), triacylglycerols (TAG) and ox‐LDL. Subjects were stratified into tertiles (weight loss, unaltered weight and weight gain groups) based on their weight change from baseline to follow‐up. Ox‐LDL was determined by baseline level of conjugated dienes in LDL lipids. Among the group of weight gainers, concentration of TAG reduced less (?0.14 vs. ?0.33, p = 0.002), HDL‐C reduced more (?0.31 vs. ?0.16, p = 0.003) and ox‐LDL/HDL‐C ratio increased (3.0 vs. ?0.2, p = 0.003) when compared to group of weight loss. Both T‐C and LDL‐C elevated more (0.14 vs. ?0.21, p = 0.008; 0.31 vs. 0.07, p = 0.015) and TAG and ox‐LDL reduced less (?0.33 vs. 0.20, p = 0.033; ?3.33 vs. ?0.68, p = 0.026) in unaltered weight group compared to weight loss group. The women who gained weight developed higher TAG and ox‐LDL/HDL‐C ratio as compared to those who lost weight. Postpartum weight retention of 3.4 kg or more is associated with atherogenic lipid profile.     

Computer aided estimation of fugitive emission rates and occupational air concentration in process design

European Union directives such as the Integrated Pollution Prevention and Control (IPPC) require inclusion of safety, environmental and health analyses in process design as part of strategies towards achieving sustainable process development. In petrochemical and organic chemical industries, which mostly handle volatile compounds, the most significant contributor to atmospheric releases is fugitive emissions that are mainly contributed by piping fittings and components. Fugitive emissions are not only of economic and environmental concern, but also a major source of background inhalative exposure to workers that may lead to various diseases including cancer. More people die every year from occupational diseases as compared to the number killed in industrial accidents. Therefore the estimation of occupational air concentration due to fugitive emission needs to be done early when developing a new process. Several methods for fugitive emissions estimation have been introduced which mostly involve manual calculations. Computer-based tools for such purpose however, are still lacking. Besides, the current methods mainly focus on the emission rates only but not on the process air concentrations. Computer aided methods for fugitive emissions assessment are highly in need, since now most of the design work is done by using computer aided process engineering (CAPE) tools. Therefore in this paper computer aided methods for quantifying fugitive emission rates and occupational air concentration are presented. Three methods are proposed for early design stages based on data available from simple process flow diagrams (PFDs), detailed PFDs or piping and instrumentation diagrams (P&IDs). The method becomes more comprehensive as it progresses from simple PFDs to P&IDs, since more process data are available later, which include plot plan, coordinates of the emission sources and local wind speed. Users however, can choose which method to use depending on the process information available in hand. The methods are demonstrated in a case study of product distillation system of toluene hydrodealkylation.     

Triacylglycerol hydroperoxides not detected in pig small intestinal epithelial cells after a diet rich in oxidized triacylglycerols

The presence of TAG hydroperoxides in the epithelial cells of the small intestines in growing pigs was studied after they had consumed a diet rich in either nonoxidized or oxidized sunflower seed oil (PV in oils, 1 and 190 mequiv O₂/kg, respectively). To obtain molecular-level information on the oxidized TAG structures, a new approach based on TLC and HPLC-electrospray ionization-MS was used in the analysis of the samples. TAG hydroperoxides were not detected in the small intestinal mucosa or adipose tissue of either group, whereas TAG hydroxides, ketones, and epoxides were detected in all samples. The results suggest that dietary TAG hydroperoxides do not lead to the appearance of these molecules in the tissues.     

What makes segmentation good? A case study in boreal forest habitat mapping

Segmentation goodness evaluation is a set of approaches meant for deciding which segmentation is good. In this study, we tested different supervised segmentation evaluation measures and visual interpretation in the case of boreal forest habitat mapping in Southern Finland. The data used were WorldView-2 satellite imagery, a lidar digital elevation model (DEM), and a canopy height model (CHM) in 2 m resolution. The segmentation methods tested were the fractal net evolution approach (FNEA) and IDRISI watershed segmentation. Overall, 252 different segmentation methods, layers, and parameter combinations were tested. We also used eight different habitat delineations as reference polygons against which 252 different segmentations were tested. The ranking order of segmentations depended on the chosen supervised evaluation measure; hence, no single segmentation could be ranked as the best. In visual interpretation among the several different segmentations that we found rather good, we selected only one as the best. In the literature, it has been noted that better segmentation leads to higher classification accuracy. We tested this argument by classifying 12 of our segmentations with the random forest classifier. It was found out that there is no straightforward answer to the argument, since the definition of good segmentation is inconsistent. The highest classification accuracy (0.72) was obtained with segmentation that was regarded as one of the best in visual interpretation. However, almost similarly high classification accuracies were obtained with other segmentations. We conclude that one has to decide what one wants from segmentation and use segmentation evaluation measures with care.     

Techniques for biased data distributions and variable classification with neural networks applied to otoneurological data

It is frequently useful and advantageous to investigate not only the classification efficacy of neural networks, but also the reasons for misclassification and relations between input variables and output classes. We have developed novel techniques to disentangle these dilemmas: a network structure and learning strategy for biased output class distributions, a method to measure the classification information incorporated in variables and variable groups, and methods to express properties learned by a network from its structure. We tested these techniques with otoneurological data from the conjunction with vertiginous diseases that we have explored in our previous neural network studies.     

Entropy analysis of wet-surface cooling system for air flow

A wet-surface heat-exchanger, where the effluent air is moistened, is analysed according to a thermodynamic theory and data of experimental tests. An entropy generation function, which takes into account the changes of temperature and humidity of air, is derived. The analyses show that it is thermodynamically possible, without any cooling machine, to achieve extremely large temperature drops. With certain parameters the system results in a maximum rate of entropy generation which is used to analyse differences between two different methods of spraying the moistening water. Approximal limits for the efficient working fluid mass flow value are also given. © 1998 John Wiley & Sons, Ltd.