Long-term ethanol consumption selectively impairs ganglioside pathway in rat brain

Gangliosides are sialo-glycosphingolipids that play important roles in the interaction of cells with their environment and are thus involved in the regulation of many cellular events. Sialic acid residues are important for the conformation of a glycomolecule, their structural stability and their functions. Although decreased brain ganglioside sialic acid has been previously reported as a result of chronic ethanol treatment in rats, no reports are available on the sialylation of specific gangliosides and/or the mechanism leading to depletion of their sialic acid residues. Therefore, in this investigation, we have examined the effects of chronic ethanol treatment on (1) incorporation of [4,5-3H]N-acetylmannosamine (ManNAc) into specific rat brain gangliosides, GD3, GD1a, GT1a, and GT1b; and (2) enzymatic activities of brain sialyltransferase and sialidase at specific subcellular levels. The experiments were done in male Wistar rats pair-fed with either ethanol or control liquid diets for a period of 8 weeks. The rats were intracerebroventricularly injected with labeled ManNAc (30 microCi/rat) and killed after 90 min. Radioactivity was determined in respective ganglioside bands separated on a thin layer chromatography system. Specific activities of sialyltransferase and sialidase were assessed using GM3 and GD3 as substrates, respectively. The results showed significant decreases of 57.7% (p < 0.001) and 68.9% (p < 0.001), respectively, in the labeled ManNAc incorporation into GD3 and GD1a fractions in rats of the ethanol group, compared with rats of the control group. No significant changes were noted in the incorporation of labeled ManNAc into GT1a or GT1b ganglioside fractions between the ethanol and control groups. Concomitantly, compared with control rats, a decrease of 18.9% (p < 0.05), 20.6% (p < 0.05), and 15.8% (p < 0.001) was found in the sialyltransferase activity, respectively, at the whole brain, and brain Golgi and synaptosomal levels. However, dramatic increases of 32.4% (p < 0.05), 105% (p < 0.001), and 150% (p < 0.001) in sialidase activity were found, respectively, at the whole brain and brain cytosol and synaptosomal fractions of rat treated chronically with ethanol. Thus, we conclude that the deleterious actions of ethanol on the sialylation of rat brain gangliosides is specific, and the reduced sialic acid label found in GD3 and GD1a in this study is mainly due to increased activity of brain sialidase. Furthermore, the study reaffirms our tenet that, regardless of whether it is the liver or the brain, glycosylation cascade is one of the main target of the deleterious attacks of ethanol.     

Ultimate capacity prediction of axially loaded CFST short columns

Composite columns have superior strength and ductility performance, and they have become more widely accepted in the engineering applications. However, the filled tubular columns require more attention. This study aims to present a new formulation for the axial load carrying capacity (N _u ) of circular concrete filled steel tubular (CFST) short columns having various geometrical and material properties. Although there have been some empirical relations for predicting N _u in the literature, genetic algorithm based explicit formulation is not available. In the current study, 314 comprehensive experimental data samples presented in the previous studies were examined to prepare a data set for training and testing of the prediction model. The prediction parameters were selected as outer diameter of column (D), wall thickness (t), length of column (L), compressive strength of concrete (f _c ), and yield strength of steel (f _y ). The prediction model was obtained by means of gene expression programming (GEP). The proposed model was compared with available ones presented in the current design codes (ACI, Australian Standards, AISC, AIJ, Eurocode 4, DL/T, and CISC) and some existing empirical models proposed by researchers. The prediction performance of all models were also evaluated by the statistical parameters. The results indicated that the GEP model was much better than the available formulae, yielding higher correlation coefficient and lower error.     

High Serum Apolipoprotein E Determines Hypertriglyceridemic Dyslipidemias, Coronary Disease and ApoA-I Dysfunctionality

The relevance of serum apolipoprotein E (apoE) levels to two hypertriglyceridemic dyslipidemias has not been clarified. We explored, in a cross-sectional (and short-term prospective) evaluation, the independent relationship of serum apoE to the atherogenic dyslipidemia, hypertriglyceridemia with elevated apoB (HtgB) and to apoA-I dysfunctionality, previously shown in Turkish adults to be independent of apoE genotype. Serum apoE concentrations were measured by immunonephelometry in 1,127 middle-aged adults. In multivariable regression analysis, apoE concentrations showed log-linear associations with apoB and apoA-I levels, waist circumference, independent of C-reactive protein (CRP), homeostatic model assessment (HOMA) index and other confounders. The likelihood of atherogenic dyslipidemia and of HtgB roughly tripled per 1-SD increment in apoE concentrations, additively to apoE genotype, HOMA, apoA-I, CRP concentrations and waist circumference; yet apoA-I, protective against atherogenic dyslipidemia, appeared to promote HtgB, a finding consistent with apoA-I dysfunctionality in this setting. Each 1-SD increment in the apoE level was moreover, associated in both genders with MetS (at OR 1.5), after adjustment for sex, age, apoB, apoA-I and CRP, or for apoE genotypes. Circulating apoE predicted in both genders age-adjusted prevalent and incident coronary heart disease (CHD), independent of apoE genotype and CRP (OR 1.32 [95 % CI 1.11; 1.58]). To conclude, in a general population prone to MetS, elevated apoE concentrations are strongly linked to HtgB and atherogenic dyslipidemia, irrespective of apoE genotype, are associated with MetS and CHD. Excess apoE reflects pro-inflammatory state and likely autoimmune activation.     

A new vortex generator geometry for a counter-flow Ranque–Hilsch vortex tube

In this study, a new geometry is introduced for the cold end side (i.e. where the swirl flow is introduced into the tube), which is called ‘helical swirl flow generator’. Effect of the helical length of the swirl flow generator on the performance of the vortex tube are investigated for varying values of other geometrical parameters as a function of the cold mass fraction, y_c. Finally, it’s disclosed that the effect of the helical length on the performance changes critically according to the value of L/D.     

Influence of dietary n-3 fatty acids on the membrane properties of skeletal muscle in pigs

The aim of the experiment was the in vivo modification of long-chain fatty acids in phospholipids and to investigate the impact on Ca²⁺ transport of sarcoplasmic reticulum (SR). Ten pigs were fed daily a diet containing 1.3 g n-3 fatty acids/kg diet (control), and ten pigs were fed a diet containing 14 g n-3 fatty acids/kg diet (n-3 diet) during the growing-finishing period. The intake of dietary n-3 fatty acids increased the percentages of these fatty acids in the phospholipids of skeletal muscle sarcoplasmic reticulum (21.6% n-3 fatty acids) and in the polar fraction of total muscle homogenates (30.7% n-3 fatty acids) significantly, compared with control (3.0% and 3.9% n-3 fatty acids, respectively), while the n-6 fatty acid concentration was reduced. In phosphatidylethanolamine of skeletal muscle polar lipids eico-sapentaenoic (EPA) and docosahexaenoic acids (DPA) were increased seven times compared with control. There were no differences in the maximal rate of Ca²⁺ uptake in skeletal muscle SR between the groups. However, the activity of Ca²⁺-ATPase of skeletal muscle SR was elevated in the n-3 diet group. It is suggested, that n-3 fatty acid enriched diet can change the complex membrane composition dependent on experimental conditions and animal species leading to different effects on membrane protein activities.     

2-D mesh-based video object segmentation and tracking with occlusion resolution

This paper integrates fully automatic video object segmentation and tracking including detection and assignment of uncovered regions in a 2-D mesh-based framework. Particular contributions of this work are (i) a novel video object segmentation method that is posed as a constrained maximum contrast path search problem along the edges of a 2-D triangular mesh, and (ii) a 2-D mesh-based uncovered region detection method along the object boundary as well as within the object. At the first frame, an optimal number of feature points are selected as nodes of a 2-D content-based mesh. These points are classified as moving (foreground) and stationary nodes based on multi-frame node motion analysis, yielding a coarse estimate of the foreground object boundary. Color differences across triangles near the coarse boundary are employed for a maximum contrast path search along the edges of the 2-D mesh to refine the boundary of the video object. Next, we propagate the refined boundary to the subsequent frame by using motion vectors of the node points to form the coarse boundary at the next frame. We detect occluded regions by using motion-compensated frame differences and range filtered edge maps. The boundaries of detected uncovered regions are then refined by using the search procedure. These regions are either appended to the foreground object or tracked as new objects. The segmentation procedure is re-initialized when unreliable motion vectors exceed a certain number. The proposed scheme is demonstrated on several video sequences.     

Space-time processing for multichannel synthetic aperture radar

Synthetic aperture radar (SAR) provides high-resolution images of a non-moving ground scene, but fails to indicate the presence and position of moving objects. As in airborne MTI (moving-target indication) systems the solution to this problem is to use an array of antennas or subapertures and several receiving channels (`MSAR', or multichannel SAR), and to apply multichannel clutter suppression. One of the most efficient methods is adaptive space-time processing (STAP), which can be simplified to frequency-dependent spatial processing in the Doppler domain. Some of these techniques applied to SAR are reviewed and illustrated with data gathered by the German experimental multichannel SAR system `AER-II'     

Comparison of the developed thermal stresses in Al2O3–SG, ZrO2–12%Si+Al and ZrO2–SG coating systems subjected to thermal loading

In this investigation, thermal and structure finite element analysis has been employed to analyse the thermal stresses developed in Al₂O₃–SG, ZrO₂–12%Si+A1 and ZrO₂–SG.coatings subjected to thermal loading. Systems with 0.4 mm coating thickness and 4 mm substrate material thickness were modelled. Zirconia–spherical cast iron (SG) coatings with NiAl, NiCrAlY and NiCoCrAlY interlayers were also modelled. Nominal and shear stresses at the critical interface regions (film/interlayer/substrate) were obtained. The results showed that the lowest stress levels are in ZrO₂–SG coatings. Furthermore, the interlayer thickness and material combinations have a significant influence on the level of the developed thermal stresses. It is also concluded that the finite element technique can be used to optimise the design and the processing of ceramic coatings.     

The Reaction-Bonded Aluminum Oxide Process: I, The Effect of Attrition Milling on the Solid-State Oxidation of Aluminum Powder

The effect of attrition milling on the solid-state oxidation of aluminum powder is important for the reaction-bonded aluminum oxide process. Attrition milling increased the surface area to 14.4 and 20.2 m²/g versus 1.2 m²/g for unmilled powder and smeared the Al particles, and the surface was hydrolyzed to form bayerite and boehmite. Upon heating the hydroxides decompose to form an 11–13 nm thick amorphous plus γ-Al₂O₃ layer which subsequently retards oxidation kinetics. The oxidation per unit area decreases for the higher surface area powders at temperatures below the critical temperature but the total oxidation of the milled powder is ∼70% versus ∼9% for the as-received powder because of the higher surface area. The critical temperature depends on Al particle surface characteristics and is defined as the transition temperature above which the initial rate of oxidation is linear, not parabolic. Above the critical temperature the oxidation per unit area decreases significantly. In addition, linear oxidation occurs faster than parabolic oxidation and thus the initial fast oxidation kinetics (i.e., linear) can cause thermal runaway during oxidation. Therefore, oxidation below the critical temperature is essential to maximize solid-state oxidation and to prevent thermal runaway. The critical temperatures for the as-received (1.24 m²/g), the 6 h (14.4 m²/g), and 8 h (20.2 m²/g) attrition-milled Al powders were 500°, 475°, and 500°C, respectively. A model for oxidation during the parabolic and linear oxidation stages is presented.     

Influence of quality of manufacture on electronic equipment and system reliability

For electronic equipment and systems a correspondance of predominant faults is observed during the electrical test phases at board and at system level prior to use, and during subsequent application of the system. Relationships are expected based on the common causes of these faults. Such faults might be those that have escaped detection during electrical testing, faults that induce secondary latent defects on parts, or original latent defects incorporated in the installed components. Causes and effects are discussed. Measures have been taken over several years to improve the manufacturing quality of electronic equipment following these aspects. It is shown, by practical experience with an electronic communication system, that an improvement of manufacturing quality by a factor of 5 has increased system reliability by about the same degree. This noticeable effect of the manufacturing quality of printed circuit board assemblies on the reliability of the system and on the failure rates of installed components is not considered by usual reliability prediction models. The observed failure rates of components are low when compared to values of prediction models, even including those component types contributing to focal points of failure with the achieved level of reliability.