Characterization of high-density polyethylene using laser-induced fluorescence (LIF)

Fluorescence intensity decays of high-density polyethylene (HDPE) films have been studied by laser-induced fluorescence (LIF). An internally cavity-dumped dye laser synchronously pumped with a mode-locked argon-ion laser was used to excite the HDPE samples. The decay in the fluorescence intensity of HDPE film is due to the carbonyl present in the film, and was shown to be dependent on the power density of the incident UV light. The fluorescence intensity decay exhibits second-order kinetics. The experimental results obtained here demonstrate that the photostability of HDPE films can be characterized by the rate coefficient of the fluorescence intensity decay.     

Operation and Control of a Full-Scale Biogas Plant Treating Wastewater from the Cleaning of Car Tanks

A 1200-m³ full-scale biogas plant treating highly polluted wastewater (WW) from the cleaning of tank cars transporting food and fodder is working stably and efficiently despite the WW is constantly varying in strength and composition, is easily acidifying, and low in alkalinity. Na₂CO₃ has to be added to maintain the digester alkalinity and the digester pH at defined values due to softened water used for car tank cleaning. Monitoring volatile organic acid concentration and controlling the alkalinity in the digester are essential for maintaining the digestion process stability. Biogas production is adapted to the demand by a modulated feeding regime. The drastic modulation of feeding is possible due to the moderate organic loading of the plant along with the high average hydraulic retention time.     

Age differences in the acculturation process.

Age differences were assessed in a conceptual model that seeks to explain how acculturation affects psychological well-being among Mexican-Americans. The data were from a national probability sample of 859 persons of Mexican descent. It was hypothesized that low acculturation creates financial stress. Moreover, low acculturation and financial stress were in turn predicted to erode feelings of personal control and self-esteem. Finally, diminished feelings of control and low self-esteem were hypothesized to exert a negative impact on psychological well-being. When data from respondents of all ages were assessed, empirical support was found for all of the hypotheses except the linkage between acculturation and financial stress. However, few age differences emerged in the model. The authors conclude that older Mexican-Americans may not be more vulnerable to the stressors associated with acculturation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maternal plasma concentrations of magnesium, calcium, zinc and copper in normal and pathological pregnancies

In this study, plasma levels of magnesium, calcium, zinc and copper were simultaneously determined in pregnancies complicated by either abortion, intrauterine growth retardation (IUGR), diabetes or EPH (edema, proteinuria, hypertension) gestosis. The levels of the four cations in non-pregnant women and in healthy, pregnant women were also determined. Compared with controls, a significant decrease in magnesium, with increase of the Ca/Mg ratio, was found in spontaneous abortions, but not when patients had a successful continuation of pregnancy. In EPH gestosis, total calcium was reduced, with a significant decrease of the plasma Ca/Mg ratio. A slight, but significant, increase in plasma zinc was observed in women affected by either diabetes or IUGR, probably as a result of reduced zinc uptake by the fetus. In addition, higher copper levels were found in the pathologies studied, with the exception of missed abortions. The possible role of an altered Ca/Mg ratio homeostasis in relation to gestational pathologies is discussed.     

Zinc Tin Oxide (ZTO) electron transporting buffer layer in inverted organic solar cell

Solution processed, high electron mobility and highly transparent Zinc Tin Oxide (ZTO) was successfully exploited as electron transporting buffer layer in an inverted organic solar cell. The device configuration of FTO/ZTO/P3HT:PCBM/WO₃/Ag was employed. For comparison, an identical device using a sol–gel derived TiO_x electron extracting layer was also fabricated. Increased short-circuit density (J_sc) and open-circuit voltage (V_oc) were generated in the devices with ZTO layer in comparison to the ones with TiO_x layer. It is attributed to a better electron transporting, hole blocking capacities and reduced recombination probabilities at electron collecting electrode with ZTO layer. A power conversion efficiency of 3.05% was achieved with ZTO devices.     

Homology modelling and molecular dynamics studies of human placental tissue protein 13 (galectin-13)

The primary structure of the newly sequence analysed placentaltissue protein 13 (PP13) was highly homologous to several membersof the ß-galactoside-binding S-type lectin (galectin)family. By homology modelling, the three-dimensional structureof PP13 was built based on high-resolution crystal structuresof homologues and also their characteristic `jellyroll' foldwas found in the case of PP13. Our model has been depositedin the Brookhaven Protein Data Bank. By multiple sequence alignmentand structure-based secondary structure prediction, we underlinedthe structural similarity of PP13 with its homologues. The secondarystructure of PP13 was identical with `proto-type' galectinsconsisting of a five- and a six-stranded ß-sheet,joined by two     

Adaptive infinite dropout for noisy and sparse data streams

Machine Learning - The ability to analyze data streams, which arrive sequentially and possibly infinitely, is increasingly vital in various online applications. However, data streams pose various...     

Plasma virus load evaluation in relation to disease progression in HIV-infected children

The purpose of the study was to investigate if the presence of vertical destruction in proximal sites influences periodontal status and healing in adjacent sites in the same proximal space without vertical destruction. The investigation was conducted as a retrospective study on a 3-year consecutive referral population of periodontitis-prone patients based on full-mouth oral radiographic examinations, probing pocket depth registrations and plaque scores. The analyses were performed by using regression analyses on a final sample of 1169 (periodontal status) and 1051 (periodontal healing) proximal sites in 163 patients. The relative radiographic attachment level (RRAL) in proximal horizontal sites did not depend on the type of destruction, vertical or horizontal, in the adjacent proximal sites. However, after non-surgical treatment, pocket-depth reduction in proximal sites with horizontal destruction was significantly reduced in the presence of a vertical destruction in the adjacent proximal site compared to the corresponding sites adjacent to a horizontal defect. It was concluded that marginal periodontal healing in proximal sites with horizontal destruction is impaired by the presence of a vertical destruction in the adjacent proximal site.     

A new accurate curvature matching and optimal tool based five-axis machining algorithm

Free-form surfaces are widely used in CAD systems to describe the part surface. Today, the most advanced machining of free from surfaces is done in five-axis machining using a flat end mill cutter. However, five-axis machining requires complex algorithms for gouging avoidance, collision detection and powerful computer-aided manufacturing (CAM) systems to support various operations. An accurate and efficient method is proposed for five-axis CNC machining of free-form surfaces. The proposed algorithm selects the best tool and plans the toolpath autonomously using curvature matching and integrated inverse kinematics of the machine tool. The new algorithm uses the real cutter contact toolpath generated by the inverse kinematics and not the linearized piecewise real cutter location toolpath.