3D Hair sketching for real-time dynamic & key frame animations

Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time.     

Pharmacological Evidence on Augmented Antiallodynia Following Systemic Co-Treatment with GlyT-1 and GlyT-2 Inhibitors in Rat Neuropathic Pain Model

The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30–60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP.     

Mass transport in a weakly stratified electrochemical cell

A study of natural convection in an electrochemical system with a Rayleigh number of the order 10¹⁰ is presented. Theoretical and experimental results for the unsteady behaviour of the concentration and velocity fields during electrolysis of an aqueous solution of a metal salt are given. The cell geometry is a vertical slot and the reaction kinetics is governed by a Butler-Volmer law. To reduce the effects of stratification, the flush mounted electrodes are located (symmetrically) in the middle parts of the vertical walls. It is demonstrated, both theoretically and experimentally, that a weak stratification develops after a short time, regardless of cell geometry, even in the central part of the cell. This stratification has a strong effect on the velocity field, which rapidly attains boundary layer character. Measured profiles of concentration and vertical velocity at and above the cathode are in good agreement with numerical predictions. For a constant cell voltage, numerical computations show that between the initial transient and the time when stronger stratification reaches the electrode area, the distribution of electric current is approximately steady.List of symbols a _i left hand side of equation system - b _i right hand side of equation system - c concentration (mol m^–3) - c dimensionless concentration - c _i concentration of species i' (mol m^–3) - c₀ initial cell concentration (300 mol m^–3) - c ₀ dimensionless initial cell concentration - c_wall concentration at electrode surface (mol m^–3) - dx increment solution vector in Newton's method - D _i diffusion coefficient of species i (m² s^–1) - D ₁ 0.38 × 10^–9 m² s^–1 - D ₂ 0.82 × 10^–9 m² s^–1 - D effective diffusion coefficient of the electrolyte (0.52 × 10^–9 m² s^–1) - _x unit vector in the vertical direction - _y unit vector in the horizontal direction - F Faraday's constant (96 487 A s mol^–1) - g acceleration of gravity (9.81 m s^–2) - i dummy referring to positive (i = 1) or negative (i = 2) ion - f current density (A m^–2) - f dimensionless current density - i₀ exchange current density (0.01 A m^–2) - J _ij Jacobian of system matrix - L length of electrode (0.03 m) - N _i transport flux density of ion i (mol m^–2 s^–1) - n unit normal vector - p pressure (Nm^–2) - p dimensionless pressure - R gas constant molar (8.31 J K^–1 mol^–1) - R _i residual of equation system - Ra Rayleigh number gL ³ c ₀/D (2.54 × 101¹⁰) - S _c Schmidt number /D (1730) - t time (s) - t dimensionless time - T temperature (293 K) - velocity vector (m s^–1) - dimensionless velocity vector - U characteristic velocity in the vertical direction - V _± potential of anode and cathode, respectively - x spatial coordinate in vertical direction (m) - x dimensionless spatial coordinate in vertical direction - x solution vector for c, and - y spatial coordinate in horizontal direction (m) - y dimensionless spatial coordinate in horizontal direction - z _i charge number of ion i Greek symbols symmetry factor of the electrode kinetics, 0.5 - volume expansion coefficient (1.24 × 10^–4 m³ mol^–1) - _s surface overpotential - constant in equation for the electric potential (–5.46) - _s diffusion layer thickness - scale of diffusion layer thickness - constant relating c/y to the Butler-Volmer law (0.00733) - kinematic viscosity (0.9 × 10^–6 m2 s^–1)     

Nanosized α-Fe2O3 and Li-Fe composite oxide electrodes for lithium-ion batteries

Nanosized α-Fe₂O₃ (ca. 50 nm) and Li-Fe composite oxides (ca. 29 nm) powders were synthesized via gel polymer route. The gels were obtained with thermal polymerization of acrylic acid solutions of iron and lithium nitrates. The calcination of these gels at temperatures from 300 °C to 500 °C results in α-Fe₂O₃ from Fe(NO₃)₃ precursor and Li-Fe composite oxides Li₂O-Fe₃O₄-LiFeO₂ from a mixed precursors of Fe(NO₃)₃ and LiNO₃. Thermal gravimetric analysis, X-ray diffraction and transmission electron microscopy were used to investigate the precursors and products. The electrochemical performance of the Fe-based oxides was also evaluated. After 200 cycles, their capacity can be as high as 1300 mAh/g for α-Fe₂O₃ and 1400 mAh/g for Li-Fe oxide while the initial capacity loss is as low as 21.8%. The Li-Fe oxide electrodes exhibit better capacity retention than the α-Fe₂O₃ electrodes. They are interesting negative electrodes for high energy density lithium-ion batteries.     

Stimulatory effect of ascorbate,the alternative electron donor of photosystem II,on the hydrogen production of sulphur-deprived Chlamydomonas reinhardtii

The green alga Chlamydomonas reinhardtii is capable of photoproducing molecular hydrogen following sulphur deprivation, which results in anaerobiosis and a suppression of oxygen evolution and thus an alleviation of the inhibitory effect of oxygen on the hydrogenase. At the same time it transiently maintains a limited supply of electrons arising from photosystem II (PSII) to the hydrogenase (Melis and Happe Plant Physiol 2001; 127:740–748). In this work, using fast chl a fluorescence and P700 measurements, we show that ascorbate (Asc), a naturally occurring PSII alternative electron donor, is capable of donating electrons to PSII in heat-treated and sulphur-deprived cells and this can be significantly accelerated by supplementing the culture with 10 mM Asc. It also enhances, about three-fold, the photoproduction of hydrogen in cells subjected to sulphur deprivation as shown by gas chromatography. Similar stimulation was obtained in the presence of diphenylcarbazide (DPC), an artificial PSII electron donor. Asc and DPC also facilitated the anaerobiosis of cells, probably via super reducing the oxygen evolving complex while feeding electrons to PSII reaction centres and the linear electron transport chain, and ultimately to the hydrogenase – as shown by the significant DCMU-sensitivity of the light-induced Asc- and DPC-dependent re-reduction of P700⁺ and hydrogen evolution.     

Synthesis and Cell Growth Inhibitory Activity of Six Non-glycosaminoglycan-Type Heparin-Analogue Trisaccharides

The design and synthesis of heparin mimetics with high anticancer activity but no anticoagulant activity is an important task in medicinal chemistry. Herein, we present the efficient synthesis of five Glc-GlcA-Glc-sequenced and one Glc-IdoA-Glc-sequenced non-glycosaminoglycan, heparin-related trisaccharides with various sulfation/sulfonylation and methylation patterns. The cell growth inhibitory effects of the compounds were tested against four cancerous human cell lines and two non-cancerous cell lines. Two d -glucuronate-containing tetra-O-sulfated, partially methylated trisaccharides displayed remarkable and selective inhibitory effects on the growth of ovary carcinoma (A2780) and melanoma (WM35) cells. Methyl substituents on the glucuronide unit proved to be detrimental, whereas acetyl substituents were beneficial to the cytostatic activity of the sulfated derivatives.     

The Irritant Effects of Pharmaceutically Applied Surfactants

Dermal or transdermal medication may lead to irritant contact dermatitis. However, little information is available on the irritant effect of surfactants which are applied in topical formulations. Our aim was to examine the irritant effect of the most frequent compounds in topical products. A murine model was applied. The following compounds were examined: sodium lauryl sulphate (SLS), polyethoxylated (40EO) hydrogenated castor oil and sucrose laurate. SLS led to severe erythema, increase in transepidermal water loss (TEWL) and induced necrosis and accumulation of neutrophylic granulocytes and lymphocytes. Exposure to sucrose laurate resulted in an elevation of TEWL, but histology did not reveal impairment of the skin structure. Application of polyethoxylated (40EO) hydrogenated castor oil was not accompanied by tissue damage. Special attention should be paid to the irritant effect of SLS. Polyethoxylated (40EO) hydrogenated castor oil seems to be a non-irritant agent and sucrose laurate is also a promising candidate for application in topical preparations.     

Fullerene-functionalized carbon nanotubes as improved optical limiting devices

We report the synthesis, characterization and optical limiting behavior of a nanohybrid built by grafting C₆₀-fullerenes on carbon nanotubes (CNTs). The nonlinear optical limiting properties of the CNT-C₆₀ complex were investigated at wavelengths where C₆₀ does not absorb. We found that the nanohybrid had superior performances to those of CNTs and fullerenes, either taken individually or as a mixture. This enhanced optical limitation of the nanohybrid suggests not only cooperative but also synergistic effects between the two carbon forms. A mechanism involving higher excitonic states of the CNTs formed by Auger recombination of low energy excitons is proposed.     

Chemical changes in asbestos-based friction materials during performance — a review

The importance of chemical changes to the performance of asbestos based friction materials is discussed. The available information is reviewed in three sections: Composite Materials, Polymers, and Inorganic Materials. The relevance of the information is discussed and conclusions drawn regarding the scope for research into this area.     

Structural and optical properties of bandgap engineered bismuth titanate by cobalt doping

The wide band gap of complex oxides is one of the major obstacles limiting their use in photovoltaic cells. To tune the bandgap of complex oxides, nano-sized bismuth titanate-based powders were synthesized by conventional solid reaction method. X-ray diffraction patterns confirmed that all powders were crystallized in an orthorhombic structure. The photoluminescence signal shows that there was no contribution to the optical bandgap from unwanted oxygen vacancy. The UV-vis absorption spectra of LaCo-BiT powder showed that the optical bandgap drastically decreased from 3.1eV to 2.5eV, while those of of BiT and La-BiT showed change in the optical bandgap. From these observations, we could experimentally confirm that cobalt atoms were responsible for the modification of the electronic structure in BiT-based oxides. This approach to controlling the bandgap could be applied to other complex oxides materials, such as other types of Aurivillius phase materials for use in emerging oxide optoelectronic and energy applications.