A rapid inversion and resolution analysis of magnetic microscope data by the subtractive optimally localized averages method

Modern scanning magnetic microscopes have the potential for fine-scale magnetic investigations of rocks. Observations at high spatial resolution produce large volumes of data, and the interpretation of these data is a nontrivial task. We have developed software using an efficient magnetic inversion technique that explicitly constructs the spatially localized Backus-Gilbert averaging kernel. Our approach, using the subtractive optimally localized averages (SOLA) method (Pijpers, R.P., Thompson, M.J., 1992. Faster formulations of the optimally localized averages method for helioseismic inversions. Astronomy and Astrophysics 262, L33-L36), yield a unidirectional magnetization. The averaging kernel expresses the spatial resolution of the inversion and is valuable for paleomagnetic application of the scanning magnetic microscope. Inversion examples for numerical magnetization patterns are provided to exhibit the performance of the method. Examples of actual magnetic field data collected from thin sections of natural rocks measured with a magnetoimpedance (MI) magnetic microscope are also provided. Numerical tests suggest that the data-independent averaging kernel is desirable for a point-to-point comparison among multiple data. Contamination by vector magnetization components can be estimated by the averaging kernel. We conclude that the SOLA method is a useful technique for paleomagnetic and rock magnetic investigations using scanning magnetic microscopy.     

Central effects of iohexol and iopamidol, non-ionic contrast media

BACKGROUND: The relationship between uveitis anterior in childhood and juvenile chronic arthritis (JCA, respectively JRA) has been known since 1950. In a review, the clinical picture of uveitis anterior, its prevalence, pathogenesis, prognosis and current therapy of ocular complications are presented. In addition, we will report our results of a clinical study. PATIENTS AND METHODS: In a cross-sectional study, 64 patients with juvenile chronic arthritis (JCA) had an ophthalmological screening for eye complications either from the disease itself or from the treatment. RESULTS: In 16% of the patients, an iridocyclitis was found, in one case acute, in 9 cases chronic. The cases of chronic uveitis anterior showed in 43% a combination with the classic risk factors (ANA-positive, oligoarticular, female). At the beginning of uveitis, the patients had a mean age of 81 months, at the beginning of JCA disease a mean age of 37 months. Four of 10 patients (= 40%) had eye complications from uveitis (cataract, posterior synechiae, glaucoma). Complications from therapy were found in 27%, mostly cataract as a complication of systemic and topical steroid treatment. Eighteen % had a visual acuity of 0.4 or less. CONCLUSIONS: Because of the often asymptomatic progression of chronic uveitis anterior, the risk of severe undetected eye complications is high. Therefore, an intensive interdisciplinary cooperation between rheumatologists, pediatrics and ophthalmologists is required.     

Pharmacokinetics of CDDP by the route of administration in patients with ovarian cancer

Seventy patients with local squamous cell carcinoma of the esophagus were treated between 1981 and 1990 with preoperative chemotherapy, surgical resection, and possible postoperative radiation therapy and/or chemotherapy. Chemotherapy included two cycles of 5-fluorouracil (1000 mg/m2) by continuous intravenous infusion on days 1-4 and cisplatin (100 mg/m2) on day 4. Complete clinical response (CCR) was achieved in 28 (41%) patients, partial clinical response (PCR) in 17 (25%), and no response in 23 (34%). Fifty-five (81%) patients were resected, 6 (9%) were explored, and 7 (10%) were unable to have surgery. Microscopic analysis of 55 resected patients showed 50 (91%) with active tumor, 1 (2%) with necrotic tumor, and 4 (7%) with a pathological complete response to chemotherapy. Twenty-six of the 55 resected patients (47%) had no gross evidence of disease at the time of surgical inspection. Median overall survival was 21.86 months (range 2-107 months) for all patients and 26.71 months (range 2-107 months) for resected patients. Actuarial 5-year survival rate was 31% for all patients and 39% for resected patients. Prolonged survival correlates with complete clinical response to chemotherapy, low pathological stage of disease, and successful resection of the lesion.     

Testing for carcinogenicity of pharmaceuticals

When two-layered artificial teeth are used, acrylic resin occlusal parts can be removed from base parts and used directly as resin patterns for casting, which facilitates fabrication of metal occlusal surfaces. Because these teeth were made of acrylic resin, it was easy to modify occlusal morphology before converting to metal. Application of two-layered artificial teeth to achieve lingual contact occlusion brought about sufficient masticatory forces and denture stability and resulted in patient satisfaction.     

Morphological differences in nuclear materials released from hamster sperm heads at an early stage of incorporation into immature oocytes, mature oocytes, or fertilized eggs

To elucidate the effects of ooplasmic factors on the early morphological changes in hamster sperm heads within the ooplasm, immature ovarian oocytes at the germinal vesicle stage (GV oocytes), ovulated fully mature oocytes, and fertilized eggs at anaphase II or the pronuclear stage (PN eggs) were examined in detail 15-30 min after insemination or reinsemination. Thin-sectioning studies demonstrated distinct materials released from the sperm nucleus over the entire postacrosomal nuclear surface immediately after disappearance of the sperm nuclear envelope. The release occurred in all of the oocytes and eggs prior to or even in the absence of subsequent chromatin decondensation. Depending upon the stage of the penetrated oocyte or egg, however, the materials varied in morphology: several hemispherical projections of amorphous material within mature oocytes; a number of electron-dense globules within GV oocytes and PN eggs; and both forms within eggs at anaphase II-telophase II. These observations and the fact that only the release of the amorphous material was accompanied by sperm chromatin decondensation indicate that this release was the initial process of chromatin decondensation, whereas the release of the globules resulted from a deficiency or lack of ooplasmic factors affecting the sperm nucleus. Restriction of the release in both forms of material to the late meiotic phase suggests changes in the factors associated with progression of meiosis. To approach an understanding of the mechanism of successful decondensation of sperm chromatin, the ooplasmic factors considered responsible for the stage-dependent release of nuclear materials are discussed.     

Nitric acid-based partial-digestion method for selective determination of inorganic arsenic in hijiki and application to soaked hijiki

Because there is a great difference between the toxicity of inorganic arsenic (As) and organic As in food, the JECFA has set a PTWI value for inorganic As (iAs) rather than for total As. The difference in As toxicity makes it necessary to extract iAs completely from food samples for toxicological analysis, but complete extraction of As from most foods including seaweed has not been achieved to date. We developed a partial-digestion method that uses nitric acid as a solvent in order to extract almost all arsenicals from the solid matrix of hijiki (Hizikia fusiforme, a brown alga) samples. In this method, organic As species were not converted into iAs. HPLC/ICP-MS was then used to determine the concentration of iAs. Total As was measured by hydride generation-atomic absorption spectrometry. The adopted conditions for 0.1 g of ground fine powder sample were: 2 mL of 0.3 mol/L nitric acid; heating, 80 degrees C for 1 hr. Intra-laboratory validation of the method showed good precision and accuracy. The repeatability and intermediate precision for iAs were 1.5% and 1.5%, respectively. The LOD and LOQ for iAs were 0.14 and 0.46 mg/kg dry weight, respectively. Recovery studies performed by spiking 0.5 mg/kg dry weight as the LOQ level and by spiking 3 mg/kg dry weight as the iAs concentration of an un-spiked hijiki sample showed good accuracy. The method was applied to hijiki samples after a water soaking process and a water soaking and simmering process. The results suggested that the As concentration in hijiki after both processes was lower than that before the treatments and that the water soaking and simmering process reduced the iAs concentration much more effectively than the water soaking process.     

Super‐ductile PBT alloy with excellent heat resistance

A super‐ductile PBT alloy with excellent heat resistance was successfully fabricated by reactive blending of poly(butylene terephthalate) (PBT) with poly(ethylene‐co‐glycidyl methacrylate) together with linear low density polyethylene (LLDPE) and hydrogenated styrene‐butadiene‐styrene block copolymer (SEBS). It possesses a unique tensile stress–strain curve with no yielding point and large elongation at break, moreover, the alloy did not show serious deterioration of the mechanical properties by high temperature annealing at 150°C for 96 h. The structure‐properties relationship is discussed on the basis of transmission electron microscopy, differential scanning calorimetry, dynamic mechanical analysis, and wide‐angle X‐ray diffraction analysis. The outstanding ductile nature seems to come from the negative pressure effect of LLDPE (or LLDPE/SEBS) particles that dilates the PBT ligament matrix to enhance the local segment motions. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.     

Crystal shape of GaAs nanocrystals deposited on Si(100) by molecular beam epitaxy

The shape changes in GaAs nanocrystals deposited on Si substrate have been studied as a function of the coverage by transmission electron microscopic observations in order to see the growth mechanism from the viewpoint of the surface energy and the lattice strain energy between the nanocrystal and the substrate. When GaAs was deposited on the Si(100) surface, the shape of the GaAs nanocrystals changes from stepped mound, hut cluster to dome structure with increasing the coverage. The shape changes are responsible for decreasing the total free energy caused by the lattice strain energy with the substrate and surface energy depending on the crystal size.     

Relaxation method for mixed boundary conditions

The numerical solution of Laplace's equation in 2-dimensional Cartesian co-ordinates with mixed boundary conditions is described using the successive-overrelaxation method for solution, with the acceleration parameter decided by a method proposed formerly. Its effectiveness is compared with that of other methods.     

Synthesis of artificial N-glycopolypeptides carrying N-acetyllactosamine and related compounds and their specific interactions with lectins

Artificial N-glycopolypeptides carrying N-acetyllactosamine (LacNAc) or related compounds were synthesized. First, sugars were converted into their corresponding beta-glycosylamines with ammonium hydrogen carbonate. Then, the beta-glycosylamines were condensated with the carboxyl groups of poly(L-glutamic acid). N-Glycopolypeptides with different degrees of substitution of sugars were isolated by passage through a column of Sephadex G-25. These synthetic polymers were used as model compounds in the analysis of oligosaccharide-lectin interactions. Interactions with some lectins were investigated by agar-gel double-diffusion tests and in terms of inhibition of hemagglutination. A glycopolypeptide substituted with LacNAc reacted with Erythrina cristagalli agglutinin (ECA), peanut (Arachis hypogaea) agglutinin (PNA), Ricinus communis agglutinin-120 (RCA120), wheat germ (Triticum vulgaris) agglutinin (WGA) lectins, which recognize either galactosyl or N-acetylglucosamine (GlcNAc) residues. Other synthetic glycopolymers carrying N-acetylisolactosamine, GlcNAc, N,N'-diacetylchitobiose, or N,N', N"-triacetylchitotriose also reacted with WGA, and these last two polymers inhibited hemagglutination most. Of these five glycopolypeptides, only the one substituted with LacNAc reacted with ECA. These sugar-substituted glycopolypeptides interacted specifically with the corresponding lectins, no matter how much shorter the sugar side chains of the glycopolymers were than those of natural glycoproteins.