Modeling a Murex cabritii sea shell with a structured implicit surface modeler

BlobTree , and its application to the generation of a complex and visually accurate biological model of the sea shell Murex cabritii. Since the model is purely procedurally defined and does not rely on polygon mesh operations, it is resolution independent and can be rendered directly using ray tracing. An interface has been built for the BlobTree using an interpreted programming language (Python). The language interface readily allows a user to procedurally describe the shell based on numeric data taken from the actual object. Published online: 15 March 2002     

Biogenic amines in striatum of rats that had been treated with ethanol, and their brains later stored in different temperatures

The purpose of this study was to investigate how ethanol pretreatment and storage temperatures of brain striatum affect levels of biogenic amines in this tissue. Adult Wistar male rats were injected with 25% ethanol (5.0 g/kg i.p.) while the control rats were administered i.p. with the same volume of saline. Two hours later the rats were decapitated, their brains removed, and the striatum separated. Each striatum was divided into three parts: one part was immediately frozen on dry ice and kept at -70 degrees C; a second fragment was kept in a household refrigerator (+4 degrees C); and the third fragment was kept at +22 degrees C. Twenty-four hours later, levels of DA, DOPAC, HVA, 3-MT, 5-HT, and 5-HIAA in the striatum were assayed by HPLC/ED. Immediately after decapitation; ethanol levels were assayed in the serum of ethanol-pretreated and saline-pretreated rats using gas chromatography. Our results indicate that levels of striatal DA, DOPAC, and HVA in saline-pretreated rats decreased significantly when the storage temperature of the striatum was raised from -70 degrees C, through +4 degrees C, to +22 degrees C, while levels of striatal 5-HT and 5-HIAA remained constant within the temperature range tested and levels of 3-MT fluctuated. In ethanol-pretreated rats, striatal levels of DOPAC, HVA, and 5-HIAA were increased in all three storage temperatures, while levels of DA, 5-HT, and 3-MT were decreased in those temperatures. Those decreases were most profound in striatal samples kept at +22 degrees C. We conclude that concern about possible interactions between drugs and biogenic amines should be exercised.     

Free vibrations of shear‐flexible and compressible arches by FEM

The purpose of this paper is to analyse free vibrations of arches with influence of shear and axial forces taken into account. Arches with various depth of cross‐section and various types of supports are considered. In the calculations, the curved finite element elaborated by the authors is adopted. It is the plane two‐node, six‐degree‐of‐freedom arch element with constant curvature. Its application to the static analysis yields the exact results, coinciding with the analytical ones. This feature results from the use of the exact shape functions in derivation of the element stiffness matrix. In the free vibration analysis the consistent mass matrix is used. It is obtained on the base of the same functions. Their coefficients contain the influences of shear flexibility and compressibility of the arch. The numerical results are compared with the results obtained for the simple diagonal mass matrix representing the lumped mass model. The natural frequencies are also compared with the ones for the continuous arches for which the analytically determined frequencies are known. The advantage of the paper is a thorough analysis of selected examples, where the influences of shear forces, axial forces as well as the rotary and tangential inertia on the natural frequencies are examined. Copyright © 2001 John Wiley & Sons, Ltd.     

Surface Tension,Density, and Thermal Expansion of (Bi-Ag)<Subscript>eut</Subscript>-Zn Alloys

The thermophysical properties of Bi-Ag eutectic-based alloys with additions of 3 at.%, 6 at.%, and 9 at.% Zn are presented. The density of liquid alloys was determined using the dilatometric method, while the surface tension was measured using the maximum bubble pressure method. Thermal expansion of solid alloys was measured with an optical dilatometric technique. It was found that addition of zinc to the Bi-Ag eutectic slightly decreases density, while an increase of the surface tension and thermal expansion coefficient is observed. Relatively good agreement is observed between surface tension calculated from the thermodynamic model and the experimental data.     

Deformable strokes towards temporally coherent video painting

We present an automatic and robust technique for creating non-photorealistic rendering (NPR) and animation, starting from a video that depicts the shape details and follows the motion of underlying objects. We generate NPR from the initial frame of the source video using a greedy algorithm for stroke placements and models, in combination with a saliency map and a flow-guided difference-of-Gaussian filter. Our stroke model uses a set of triangles whose vertices are particles and whose edges are springs. Using a physics-based framework, the generated and rendered strokes are translated, rotated and deformed by forces exerted from the sequential frames. External forces acting on strokes are calculated according to temporally and spatially smoothed per-pixel optical flow vectors. After simulating each frame, we delete unnecessary strokes and add new strokes for disappearing and appearing objects, but only if necessary to avoid popping and scintillation. Our framework automatically generates the coherent animation of rendered strokes, preserving the appearance details and animating strokes along with the underlying objects. This had been difficult to achieve with previous user-guided methods and automatic but limited transformations methods.     

Label-dependent node classification in the network

Relations between objects in various systems, such as hyperlinks connecting web pages, citations of scientific papers, conversations via email or social interactions in Web 2.0 portals are commonly modeled by networks. One of many interesting problems currently studied for such domains is node classification. Due to the nature of the networked data and the unavailability of collection of nodes' broad representation for training in majority of environments, only a very limited data may remain useful for classification. Therefore, there is a need for accurate and efficient algorithms that are able to perform good classification based only on scanty knowledge of network nodes.A new approach of sampling algorithm—LDGibbs, used in the context of collective classification with application of label-dependent features, is proposed in the paper in order to provide more accurate generalization for sparse datasets. Additionally, a new LDBootstrapping algorithm based on label-dependent features has been developed. Both new algorithms include additional steps to extract new input features based on graph structures but limited only to the nodes of a given label. It means that a separate set of structural features is provided for each label. The comparison with the other approaches, in particular with standard Gibbs Sampling and bootstrapping provided satisfactory results and revealed LDGibbs's superiority.     

Photodegradation of poly(neopentyl terephthalate)

In this paper we investigate the mechanism of photodegradation in simulated sun light (in a SUNTEST XXL+) of a polyester based on terephthalic units (poly(neopentyl terephthalate); PNT). The mechanisms of degradation were studied with MALDI-ToF MS, ATR-FTIR and SEC.     

Enriching breakfast sausages by feeding pigs with CLA supplemented diets

Approaches for improving the profile of functional unsaturated fatty acids in pork products include dietary supplementation of pigs with functional oils. Little information is available to indicate the benefit of this approach in a processed and cooked pork product such as breakfast sausages. Therefore, the aim of the present study is to examine the fatty acid profile and oxidation level in cooked pork sausages, produced following dietary supplementation with CLA compared to sunflower oil (SFO). Fat and moisture percentages, total fatty acid profiles and TBARS were analysed. Fatty acid profiles were altered in the sausages following all treatments. While a stronger effect was seen for CLA treatments, addition of SFO in the diet also resulted in linear increases of CLA in the sausages. CLA supplementation resulted in increased saturated fatty acid content; however, all treatments were within the recommended polyunsaturated/saturated fatty acid ratio of above 0.4. Improved oxidative stability was observed in sausages from CLA supplemented diets.     

Transient Capillary Channel Flow Stability

Capillary channel techniques with free liquid surfaces provide very reliable means for liquid management in space. However, capillary channel flow is subject to limitation due to liquid surface instabilities when a critical flow rate is reached. Steady flow rate limitation is a consequence of the choking effect and well understood. Critical steady flow rate computation with a one-dimensional model is related to a numerical singularity which occurs at critical flow. For transient flow the singularity does not occur. Therefore, a new transient stability model is defined. It is based on the steady model, a simplified transient momentum balance, the consideration of the capillary pressure of typical observed surface shapes, and on a simplified dynamic inside the channel. The balance and dynamic are defined by liquid and geometrical properties only and therefore significantly easier to compute than a transient differential equation system. In 2011, experiments were performed in cooperation with NASA on the International Space Station (ISS) to confirm the model for steady flow and validate the new transient model. A new phenomenon is discussed, the flexibility effect, which provides significant additional transient stability for channels of sufficient length. An undesired feedback effect, provoked by the reuse of the liquid in a circular loop of the experimental setup, and which influenced the measurements, is compensated by a semi-empirical model for a feedback ratio.