Putative association between a new polymorphism in exon 3 (Arg109Cys) of the pancreatic colipase gene and type 2 diabetes mellitus in two independent Caucasian study populations

The protein encoded by the pancreatic colipase (CLPS) gene is an essential cofactor needed by pancreatic triglyceride lipase (PNLIP) for efficient dietary lipid hydrolysis. Since the inhibition of lipase activity was shown to reduce the incidence of type 2 diabetes mellitus, we tested the hypothesis that genetic variations in the CLPS and PNLIP genes are associated with type 2 diabetes; 47 unrelated subjects were screened for polymorphisms of the CLPS and PNLIP genes. A nested-case control study of 192 incident type 2 diabetes subjects and 384 sex- and age-matched controls taken from the European Prospective Investigation into Cancer and Nutrition Potsdam Cohort (EPIC) was employed for association studies. The Metabolic Intervention Cohort Kiel (MICK) consisting of 716 males was used for verification. A novel putative functional polymorphism (Arg109Cys) was identified in the CLPS gene. The frequencies of the Arg/Cys genotype were 2.6% in EPIC and 2.2% in MICK study subjects. No homozygotes for the Cys/Cys genotype were found in either study population. Logistic regression analysis showed a statistically significant association of the Arg/Cys genotype with an increased risk of type 2 diabetes. The odds ratios estimated by the model were 3.75 (95%CI = 1.13-12.49, p = 0.03) in EPIC and 4.86 (95%CI = 1.13-20.95, p = 0.03) in MICK. No comparable associations were found with other traits of the insulin-resistance syndrome (e. g.; body mass index, waist to hip ratio). In conclusion, we obtained evidence in two German Caucasian study populations that the variant of the rare CLPS Arg109Cys polymorphism might contribute to increased susceptibility of type 2 diabetes.     

Piezoelectric two-layer stacks of cellular polypropylene ferroelectrets: transducer response at audio and ultrasound frequencies

Piezoelectric cellular polypropylene films, so-called ferroelectrets, are assembled in a stack with two active transducer layers. The stack is characterized with respect to its linear and quadratic response in a frequency range from 1 kHz to 80 kHz. A relatively smooth frequency response in the sound-pressure level is found for the individual layers as well as for both layers driven in phase. The piezoelectric response of the two-layer stack is twice the response of an individual layer over a rather broad frequency range. Furthermore, the influence of the preparation conditions on the resonance frequency and the effect of the quadratic distortion on the radiated sound are investigated both for the individual transducer films in the stack and for the stack system as a whole.     

Low-temperature fabrication of dye-sensitized solar cells by transfer of composite porous layers

Dye-sensitized solar cells have established themselves as a potential low-cost alternative to conventional solar cells owing to their remarkably high power-conversion efficiency combined with 'low-tech' fabrication processes. As a further advantage, the active layers consisting of nanoporous TiO2 are only some tens of micrometres thick and are therefore in principle suited for flexible applications. However, typical flexible plastic substrates cannot withstand the process temperatures of up to 500 degrees C commonly used for sintering the TiO2 nanoparticles together. Even though some promising routes for low-temperature sintering have been proposed, those layers cannot compete as regards electrical properties with layers obtained with the standard high-temperature process. Here we show that by a lift-off technique, presintered porous layers can be transferred to an arbitrary second substrate, and the original electrical properties of the transferred porous layers are maintained. The transfer process is greatly assisted by the application of composite layers comprising nanoparticles and nanorods.     

Tunable double quantum dots in InAs nanowires defined by local gate electrodes

We report on low-temperature transport measurements on single and double quantum dots defined using local gates to electrostatically deplete InAs nanowires grown by chemical beam epitaxy. This technique allows us to define multiple quantum dots along a semiconducting nanowire and tune the coupling between them.     

Liquid crystalline nanowires in porous alumina: geometric confinement versus influence of pore walls

Aligned liquid crystalline nanowires within ordered porous alumina templates show a pronounced texture on a macroscopic scale. We have investigated the influence of the geometric confinement and the nature of the pore walls on the mesophase formation by means of X-ray diffraction. The apparent texture is the result of a complex interplay of the pore geometry, interfacial phenomena, and the thermal history. Pores with a diameter of a few hundred nm guide the mesophase formation more efficiently than those with a diameter below 100 nm.     

A Modal Multifield Approach for an Extended Flexible Body Description in Multibody Dynamics

This paper presents a new methodology to simulate the behaviour of flexible bodies influenced by multiple physical field quantities in addition to the classical mechanical terms. The theoretical framework is based on the extended Hamilton Principle and an adapted modal multifield approach. Furthermore, the use of finite element analysis for the necessary data preprocessing is explained. Numerical solution strategies for the coupled system of differential equations with different time scale properties are mentioned. The method is applied to simulate a structure with distributed piezo-ceramic devices inducing an additional electrostatic field. Two thermoelastic problems, which have to consider the influence of spatial temperature distribution, also demonstrate the benefits of the presented approach.     

Korrelation zwischen Kolbenringbruch und Kolbenringflanken-Verschleißbeschleunigung

Relationship between Piston Ring Fracture and Piston Ring Flank Wear Acceleration In wear measuring experiments on diesel engines a relationship between the fracture of the first piston ring and the wear acceleration of the ring flank of the same piston ring was found. A special series of the experiments was designed to clarify this connexion. The results from both the initial experiments and the extra series of experiments are described.     

Richtlinien für Werkstoffauswahl und Korrosionsschutz in der chemischen Industrie

Criteria for the selection of materials and corrosion protection in the chemical industry In chemical technology, the technical requirements to be met by materials as well as the protection measures against corrosion become more differentiated. On the other hand, owing to the technical progress in the sphere of materials number of alternative solutions to cope with these specifications is becoming available. The selection process, which has thus become more difficult, must lead to an overall solution representing the economic optimum; but must not become too expensive in the planning of new plant or in the corrosion protection of existing plant. A distinction is made between, and a brief outline given of, several stages in the material selection process, viz. formulation of requirements; selection methods prior to testing; laboratory tests; utilisation of technical testing plants; tests under operating conditions; determining the correct solution. The economic calculations designed to determine the most favourable technical solution call for numerous technical data (e.g., the corrosion rates under different corrosion conditions) as well as economic data (especially the capital and annual costs depending on the material). The calculation and estimating methods suitable for this purpose are described in detail. In order to reduce the costs incurred through corrosion, money must be spent on certain protective measures. This relationship is illustrated by the phenomenon of cost substitution. Finally, a synopsis is given of all the practicable methods suitable for determining the optimum conditions.     

Enzymatic examination of citrate-isocitrate accumulation in yeasts

The activities of the enzymes citrate synthase, aconitate hydratase, isocitrate dehydrogenase and isocitrate lyase in cell homogenates of n-paraffin grown citrate plus isocitrate accumulating yeasts (C. lipolytica high rate accumulating strain and C. guilliermondii low rate accumulating strain) were determined. It is shown that the activities of the enzymes decline after transition from tropho- to idiophase and remain constant with exception of isocitrate lyase which diminishes slowly. The decline in activity of the isocitrate lyase was greatest in the cells of C. guilliermondii. It is discussed that the differences of the enzymatic activities in the tropho- and idiophase, resp. may be artefacts due to changes in the structure of cellular envelope, but that the decline of lyase activity in the idiophase could be one factor determining the rate of citric- and isocitric acid overproduction. The diminishing of isocitrate lyase in the course of idiophase is interpreted as example of a disappearing enzyme no further needed for normal function of the cells.