Separation of crude palm oil components by semipreparative supercritical fluid chromatography

Successful separation of triglycerides, diglycerides, free fatty acids, carotenes, tocopherol, and tocotrienols from crude palm oil has been achieved by supercritical fluid chromatography (SFC) with a combination of a C18 and a silica gel column. The separation was carried out by the programmed extraction elution method. Free fatty acids were separated into five components by gas-liquid chromatography; tocopherol and tocotrienols were also separated into four components by SFC analysis, and the pure fractionated carotenes were obtained by preparative SFC. Thus, by using supercritical fluid chromatography, crude palm oil components can be separated and fractionated, based on differences in their functional groups.     

A contribution to the UV degradation of polyurethanes

The effects of the nature of the polyols used in polyurethane (PUR) synthesis on the structural transformations after ageing by UV irradiation has been studied. The investigations were performed on PUR prepared from polyester and polyether diol oligomers. The characterization of the samples before and after ageing in view of the structural changes, which influence the course of the photooxidative degradation and photocrosslinking as well as in view of changes of mechanical properties has been done. Comparative investigations were performed by spectroscopic and viscometric measurements. The results show pronounced heterogeneity of the degradative reactions, including the existence of crosslinking processes and producing thus very inhomogeneous polymeric material. The course and the intensity of photooxidative degradation of PUR differ together with changes of mechanical properties depending whether polyester or polyether polyol have been used. The processes of photooxidative degradation is less expressed in polyesterurethane then in polyurethane based on polyether, under the same conditions of experiments. Different structures of polyester diols caused the various ageing behaviour of PUR too.     

Infrared thermography for inspecting the adhesion integrity of plastic welded joints

This work aim at developing a non-destructive tool for the evaluation of bonded plastic joints. The paper examines infrared thermographic transmission and reflection mode imaging and validates the feasibility of the thermal NDT approach for this application. Results demonstrate good estimation performance for adhesion integrity, uniformity and bond strength using a transmission mode application of infrared thermography. In addition, results from a pulsed infrared thermographic application using a modified dynamic infrared tomography scheme show good performance for estimating adhesion layer thickness mapping and detecting delaminations.     

A study of the thermal expansion of isostructural organic radical cation salts κ-(BEDT-TTF)2Cu[N(CN)2]X (X = Br, Cl,I)

High resolution thermal expansion measurements on single crystals of κ-(BEDT-TTF)₂Cu[N(CN)₂]X, with X = Br, Cl, I were performed along the three principal directions in the temperature range from 2 to 300K. The temperature dependence of the linear thermal expansion of the two superconductors (X = Br, Cl) is found to be completely different from that of the non-superconducting I-salt. Cooling the I-crystal, we found an elongation of the c- axis, a larger contraction of the a-axis and a smaller contraction of the b-axis in comparison to the bromide- and the chloride- salt. Common to the three compounds are large anomalies in the linear thermal expansion coefficients _i at a temperature T_d = 84K, 80K, 73K for X = I, Br, Cl, respectively. The magnitude and the sign of these anomalies in _i strongly depend on the anion composition. At T_d the _i's show steplike changes, which lead to a lattice distortion of opposite sign for the superconductors and for the I-salt. These anomalies indicate a second order phase transition at T_d, which eventually may be related to a disorder-order transformation of the terminal ethylene groups of the donor molecules.     

Refined mapping of a gene responsible for Fukuyama-type congenital muscular dystrophy: evidence for strong linkage disequilibrium

Fukuyama-type congenital muscular dystrophy (FCMD), the second most common form of childhood muscular dystrophy in Japan, is an autosomal recessive severe muscular dystrophy associated with an anomaly of the brain. After our initial mapping of the FCMD locus to chromosome 9q31-33, we further defined the locus within a region of approximately 5 cM between loci D9S127 and CA246, by homozygosity mapping in patients born to consanguineous marriages and by recombination analyses in other families. We also found evidence for strong linkage disequilibrium between FCMD and a polymorphic microsatellite marker, mfd220, which showed no recombination and a lod score of (Z) 17.49. A "111-bp" allele for the mfd220 locus was observed in 22 (34%) of 64 FCMD chromosomes, but it was present in only 1 of 120 normal chromosomes. This allelic association with FCMD was highly significant (chi 2 = 50.7; P < .0001). Hence, we suspect that the FCMD gene could lie within a few hundred kilobases of the mfd220 locus.     

Superconductivity in the tetragonal phase of La1.9Bi0.1CuO4+δ annealed under high oxygen pressure

We have investigated the relation between the crystal structure and superconductivity in La_1.9Bi_0.1CuO₄₊ , in which the phase separation observed in La₂CuO₄₊ is suppressed. A phase diagram in theT– plane is given for La_1.9Bi_0.1CuO₄₊ with excess oxygen. For very small values, the crystal structure is orthorhombic, and an orthorhombic-tetragonal phase transition occurs markedly at 0.03 in the measured temperature range between 13 and 293 K. Superconductivity is observed in the range of 0.04<<0.11. This is clear evidence thathigh-T _c superconductivity also appears in the tetragonal phase.     

Derivation and implementation of a cone-beam reconstruction algorithm for nonplanar orbits

B.D. Smith (ibid., vol.MI-4, p.15-25, 1985; Opt. Eng., vol.29, p.524-34, 1990) and P. Grangeat (These de doctorat, 1987; Lecture Notes in Mathematics 1497, p.66-97, 1991) derived a cone-beam inversion formula that can be applied when a nonplanar orbit satisfying the completeness condition is used. Although Grangeat's inversion formula is mathematically different from Smith's one, they have similar overall structures to each other. The contribution of the present paper is two-fold. First, based on the derivation of Smith, the authors point out that Grangeat's inversion formula and Smith's one can be conveniently described using a single formula (the Smith-Grangeat inversion formula) that is in the form of space-variant filtering followed by cone-beam back projection. Furthermore, the resulting formula is reformulated for data acquisition systems with a planar detector to obtain a new reconstruction algorithm. Second, the authors make two significant modifications to the new algorithm to reduce artifacts and numerical errors encountered in direct implementation of the new algorithm. As for exactness of the new algorithm, the following fact can be stated. The algorithm based on Grangeat's intermediate function is exact for any complete orbit, whereas that based on Smith's intermediate function should be considered as an approximate inverse excepting the special case where almost every plane in 3D space meets the orbit. The validity of the new algorithm is demonstrated by simulation studies.     

A novel radial orientation treatment of nematic liquid crystals using magnetic field lines with permanent magnet and applying the assisted electric field

Recently, there has been considerable research on optical devices, such as liquid crystal (LC) lenses and special optical plates, using LCs. In such devices, relatively small LC cells are frequently used, or unique LC orientations are required. As an LC orientation process, we focused on the LC director's orientation induced by the magnetic force line distribution of a small neodymium magnet. We propose a simple method for obtaining radial orientation, which is rather difficult to obtain using the ordinary rubbing method. The initial orientation in the LC cell is a vertical orientation cell with almost zero azimuth anchoring. With the proposed method, the reorientation process is performed with an assisting electric field and a small permanent magnet, unlike the conventional magnetic field orientation process that requires a large electromagnet. Furthermore, a polymer stabilization treatment is used to fix the obtained radial orientation pattern in the LC cell. After the treatment, the applying voltage can control the tilt angle of the director in weak polymer treatment, and a completely fixed orientation pattern can be obtained that in strong.     

Revolving Vernier Mechanism Controls Size of Linear Homomultimer

A new kind of the Vernier mechanism that is able to control the size of linear assembly of DNA origami nanostructures is proposed. The mechanism is realized by mechanical design of DNA origami, which consists of a hollow cylinder and a rotatable shaft in it connected through the same scaffold. This nanostructure stacks with each other by the shape complementarity at its top and bottom surfaces of the cylinder, while the number of stacking is limited by twisting angle of the shaft. Experiments have shown that the size distribution of multimeric assembly of the origami depends on the twisting angle of the shaft; the average lengths of the multimer are decamer, hexamer, and tetramer for 0°, 10°, and 20° twist, respectively. In summary, it is possible to affect the number of polymerization by adjusting the precise shape and movability of a molecular structure.     

Heparan sulfate proteoglycan on endothelium efficiently induces integrin-mediated T cell adhesion by immobilizing chemokines in patients with rheumatoid synovitis

OBJECTIVE: To clarify the role of heparan sulfate proteoglycan (HSPG) and chemokines in integrin-mediated T cell adhesion to endothelial cells in the synovium of patients with rheumatoid arthritis (RA). METHODS: Endothelial cells were purified from RA synovium. Expression of heparan sulfate, chemokines, and adhesion molecules on the endothelium was assessed by immunohistochemical analysis or flow cytometry. The effects of chemokines and heparan sulfate on T cell adhesion to RA endothelium were estimated with relevant antibodies and signaling inhibitors. Production of chemokines from synovial T cells was detected by Northern blotting and enzyme-linked immunosorbent assay. RESULTS: The endothelium in RA synovium highly expressed HSPG. The soluble form of chemokines, macrophage inflammatory protein 1beta (MIP-1beta), induced T cell adhesion to the endothelial cells. When MIP-lalpha and MIP-1beta were immobilized on RA endothelial cells, a more efficient integrin-mediated adhesion of T cells was induced compared with their soluble form. The induced T cell adhesion was reduced by pretreatment with either heparitinase, anti-MIP-lalpha antibody, or anti-MIP-lbeta antibody, indicating that these chemokines were bound to heparan sulfate on the cells. T cell adhesion was also inhibited by pertussis toxin, wortmannin, and cytochalasin B. MIP-lalpha and MIP-1beta were found on vessels in RA synovium in vivo, which were spontaneously produced from T cells purified from RA synovium. CONCLUSION: Endothelial cells in RA synovium characteristically express HSPG, which is involved in T cell integrin triggering by "posting" chemokines, which are produced by synovial T cells, and by "relaying" them to their receptors on T cells, which activate G protein-dependent phosphoinositide 3-kinase and actin-dependent integrin triggering.