A novel and simple approach for assessing the freshness of hazelnuts

Visual inspection and sensory analysis are the only suitable ways to assess the quality of hazelnuts under routine conditions. To obtain a more objective parameter for the freshness, a fast and easy-to-use method was developed. It is based on the well-known test for the germination capacity of seeds where their vitality is determined by use of 2,3,5-triphenyltetrazolium chloride (TTC) which is reduced by flavo enzymes to 1,3,5-triphenylformazane, which appears red. For the determination, 100 hazelnut halves were embedded in TTC containing methyl cellulose gel on a glass plate and kept at 35 °C in the dark. After 6 h, the cut planes of viable nuts were stained red, the cut planes of rotten nuts were yellow or brown, and the colour of dead or mould-infected nuts remained unchanged. The colour pattern was examined either visually by counting the coloured halves or with computer support using image editing software. The ratio of the sum of coloured areas to the total area of the hazelnut cut planes gave a measure of the average degree of viability ("vitality index"). The analysis of several samples of hazelnuts of well-defined age and storage conditions confirmed the efficiency of the method.     

Control Points for Multivariate B-Spline Surfaces over Arbitrary Triangulations

This paper describes first results of a test implementation that implements the new multivariate B-splines as recently developed by Dahmen et al. 10for quadratics and cubics. The surface scheme is based on blending functions and control points and allows the modelling of   C ^{k − 1}  -continuous piecewise polynomial surfaces of degree k over arbitrary triangulations of the parameter plane. The surface scheme exhibits both affine invariance and the convex hull property, and the control points can be used to manipulate the shape of the surface locally. Additional degrees of freedom in the underlying knot net allow for the modelling of discontinuities. Explicit formulas are given for the representation of polynomials and piecewise polynomials as linear combinations of B-splines.     

Preparation and Thermoelectric Characterization of SiC-B<Subscript>4</Subscript>C Composites

SiC-B₄C composites with various values of SiC-to-B₄C ratio and grain size were fabricated by pressureless sintering. This paper presents the results of current investigations of this composite material. This includes the parameters of manufacture (shrinkage, density, and open porosity), thermoelectric properties (electrical and thermal conductivity, and thermopower), and material characterization (x-ray diffraction, scanning electron microscopy, oxidation resistance, and thermal expansion). The results indicate high potential of this composite as an alternative material for thermoelectric applications at high temperatures. The Seebeck coefficient of the composite was higher than that of the single-component materials B₄C and SiC and reached 400 μV/K at 500°C.     

Commissioning of a state-controlled high-powered electrical driveusing evolutionary algorithms

The subject of this research is the automated startup procedure of a PI state-controlled rolling-mill motor by using evolutionary algorithms. Compared to the conventional PI speed control, applying the method of deliberate pole placement to the state controller design succeeds in improving the transient response of setpoint and disturbance changes. To put the PI state-controlled drive with observer into operation to obtain a controller with a high robustness and dynamics, the precise knowledge of this physical parameter is necessary. An evolution-based system is used to solve the estimation problem. A high degree of reliability respecting multimodal characteristics and robustness against random noise is expected from the identification method. Evolutionary algorithms fulfill this requirement. With genetic operators like mutation, crossover, and selection, evolutionary algorithms mimic the principles of organic evolution in order to solve the optimization problem     

一种超越AEC Q100/101认证标准的可靠性设计

本文在对现代汽车电子行业重要元件IGBT的故障机制进行分析的基础上,提出了一种可确保超越AEC Q100/101汽车质量认证标准的可靠性设计方案,并对其流程和独特性进行了详细的说明.     

Immunological Response to Biodegradable Magnesium Implants

The use of biodegradable magnesium implants in pediatric trauma surgery would render surgical interventions for implant removal after tissue healing unnecessary, thereby preventing stress to the children and reducing therapy costs. In this study, we report on the immunological response to biodegradable magnesium implants—as an important aspect in evaluating biocompatibility—tested in a growing rat model. The focus of this study was to investigate the response of the innate immune system to either fast or slow degrading magnesium pins, which were implanted into the femoral bones of 5-week-old rats. The main alloying element of the fast-degrading alloy (ZX50) was Zn, while it was Y in the slow-degrading implant (WZ21). Our results demonstrate that degrading magnesium implants beneficially influence the immune system, especially in the first postoperative weeks but also during tissue healing and early bone remodeling. However, rodents with WZ21 pins showed a slightly decreased phagocytic ability during bone remodeling when the degradation rate reached its maximum. This may be due to the high release rate of the rare earth-element yttrium, which is potentially toxic. From our results we conclude that magnesium implants have a beneficial effect on the innate immune system but that there are some concerns regarding the use of yttrium-alloyed magnesium implants, especially in pediatric patients.     

Siponimod Modulates the Reaction of Microglial Cells to Pro-Inflammatory Stimulation

Siponimod (Mayzent^®), a sphingosine 1-phosphate receptor (S1PR) modulator which prevents lymphocyte egress from lymphoid tissues, is approved for the treatment of relapsing-remitting and active secondary progressive multiple sclerosis. It can cross the blood–brain barrier (BBB) and selectively binds to S1PR1 and S1PR5 expressed by several cell populations of the central nervous system (CNS) including microglia. In multiple sclerosis, microglia are a key CNS cell population moving back and forth in a continuum of beneficial and deleterious states. On the one hand, they can contribute to neurorepair by clearing myelin debris, which is a prerequisite for remyelination and neuroprotection. On the other hand, they also participate in autoimmune inflammation and axonal degeneration by producing pro-inflammatory cytokines and molecules. In this study, we demonstrate that siponimod can modulate the microglial reaction to lipopolysaccharide-induced pro-inflammatory activation.     

Modulation of Specific Sphingosine-1-Phosphate Receptors Augments a Repair Mediating Schwann Cell Phenotype

Transdifferentiation of Schwann cells is essential for functional peripheral nerve regeneration after injury. By activating a repair program, Schwann cells promote functional axonal regeneration and remyelination. However, chronic denervation, aging, metabolic diseases, or chronic inflammatory processes reduce the transdifferentiation capacity and thus diminish peripheral nerve repair. It was recently described that the sphingosine-1-phosphate receptor (S1PR) agonist Fingolimod enhances the Schwann cell repair phenotype by activation of dedifferentiation markers and concomitant release of trophic factors resulting in enhanced neurite growth. Since Fingolimod targets four out of five S1PRs (S1P1, S1P3-5) possibly leading to non-specific adverse effects, identification of the main receptor(s) responsible for the observed phenotypic changes is mandatory for future specific treatment approaches. Our experiments revealed that S1P3 dominates and that along with S1P1 acts as the responsible receptor for Schwann cell transdifferentiation as revealed by the combinatory application of specific agonists and antagonists. Targeting both receptors reduced the expression of myelin-associated genes, increased PDGF-BB representing enhanced trophic factor expression likely to result from c-Jun induction. Furthermore, we demonstrated that S1P4 and S1P5 play only a minor role in the adaptation of the repair phenotype. In conclusion, modulation of S1P1 and S1P3 could be effective to enhance the Schwann cell repair phenotype and thus stimulate proper nerve repair.     

On Hermite interpolation with B-splines

Polar forms are used to find the B-spline control points for Hermite interpolation.