Nitric oxide (NO) production in mammalian non-tumorigenic epithelial cells of the small intestine and macrophages induced by individual strains of lactobacilli and bifidobacteria

Nitric oxide (NO) affects multiple gastrointestinal functions, including mucosal inflammation and antimicrobial activity. The aim of this study was to screen the ability of probiotic bacteria to stimulate NO production in porcine intestinal epithelial cells and macrophages in the presence and absence of interferon gamma (INF-γ). Production of NO in intestinal epithelium was stimulated by individual strains of lactobacilli without INF-γ priming. While none of the tested bifidobacteria were capable of inducing NO production, most constitutively secreted NO. Most tested strains induced a significant increase in NO production compared with the control cells in the macrophage cell line 3D4/21. Results support the protective role of the individual strains of the genera Lactobacillus and Bifidobacterium and may lead to new approaches for manipulating and regulating immune responses at the mucosal surfaces of the gastrointestinal tract.     

Hidden logistic potentials of working systems

Nowadays, the companies operate in a turbulent environment caused by various effects of global market, quick expansion of new products and production processes, fastidious customers and increased competition.In these circumstances only those companies are successful which can respond to market changes as fast as possible—i.e. they have the shortest response time regarding fulfilment of customer requirements (short delivery time and reliable delivery in addition to price and quality).Consequently, a reduction of mean inventory, range and lead time of working systems in the company is an ever increasing strategy that ensures an increase of growth and profit of the company.The article shows how the tools for modelling the flow of orders through working systems can be used in order to discover the hidden logistic potentials of working systems in a company.Presented are the results of finding hidden logistic potentials of working systems in the tool-production department of "ETI d.d." company from Izlake, Slovenia.     

Online assessment of power transmission belt geometry by using laser triangulation and profile parameterisation

We present a method that enables an automated assessment of the geometrical dimensions of power transmission belts and the detection of surface defects and small deviations from the ideal shape that are difficult to detect with a visual inspection. The method is based on the acquisition of belt surface profiles using a laser triangulation and automated profile assessment based on a custom-developed algorithm. The algorithm uses a novel approach to profile segmentation, featuring a template that defines the expected profile shape in advance and so, allows a faster implementation of the algorithm. It enables an automated calculation of the basic geometrical dimensions, which define the profile shape in the technical drawing and are important for online quality control in the production line. A macrolanguage was developed for a rapid and flexible definition of the mathematical operations used in the calculation of the profile's dimensions and thus, an adaptation to the requirements of a particular application. We demonstrate the use of the automatic belt profile geometry assessment on randomly chosen samples.     

Numerical simulation of rotational symmetric tube bulging with inside pressure and axial compression

The process of rotational symmetric tube bulging with inside pressure and axial compression enables the standard tubes to be formed into different rotational symmetric hollow parts in such a way that their central part is expanded into a desired shape while the ends remain unchanged. The superposition of axial compression contributes to a more favorable forming stress state, which is reflected in larger forming limits and smaller wall thinning in the widened area. The problems characterizing the process are a limited range of compression stability and difficulties met when establishing and optimizing the technological parameters of the process whose course cannot be defined in an analytical way. Based on a physical model of the forming process a numerical model was built. Using ABAQUS code the model was simulated over the entire stress/forming region. The comparison of the computer simulated forming process with the experimentally obtained results showed that the model was highly accurate. Finally, the paper studies the influences of particular parameters on the stability of the process, showing on a practical example how it is possible to achieve tube bulging without wall thinning.     

Flow through packed bed reactors: 2. Two-phase concurrent downflow

A model for the prediction of pressure drop and liquid holdup for trickling flow in packed bed reactors has been developed, based on the relative permeability concept. The relative permeabilities for gas and liquid as functions of corresponding phase saturations have been studied with 1300 newly measured data pairs of pressure drop and liquid holdup obtained for a wide range of commercially relevant operating conditions (including pressures up to 50 bar) as well as types of packing (both in terms of size and shape). The relative permeabilities are found to be solely the functions of corresponding phase saturations and it is shown that the functional form of the correlations developed, which are otherwise purely empirical by nature, has its roots in the physics of flow at the microscale level. The proposed model requires no prior experimental knowledge about the packed bed and is able to predict liquid holdup and pressure drop to within 5% and 20%, respectively, regardless of the type of packing or operating range investigated.     

A large-displacement 65Pb(Mg1/3Nb2/3)O3–35PbTiO3/Pt bimorph actuator prepared by screen printing

In this paper we present a novel approach to preparing large-displacement 65Pb(Mg_1/3Nb_2/3)O₃–35PbTiO₃/Pt (65/35 PMN–PT/Pt) bimorph actuators. These “substrate-free”, bending-type actuators were prepared by screen-printing the 65/35 PMN–PT and Pt thick-film pastes as the electrodes on alumina substrates. After this screen printing and the subsequent firing the 65/35 PMN–PT/Pt composites were peeled off from the substrates. Displacements of nearly 100 μm at 18 V were achieved for actuators with dimensions of 1.8 cm × 2.5 mm × 50 μm for the 65/35 PMN–PT layer. The normalized displacement (the displacement per unit length) was 40 μm/cm at 18 V. The experimental results together with a computation procedure were used to obtain the material parameters for a finite-element analysis of the 65/35 PMN–PT/Pt bimorph actuators.