Synthesis of 1- and 2-Chloro-7 H -benz[ de ]anthr-7-one

Chloro-7 H -benz[ de ]anthr-7-ones (chlorobenzanthrones) are useful as starting materials for synthesis of larger polycyclic aromatic compounds by means of condensation. In the synthesis, the position of the chlorine atom is very important because the structure of condensation products strongly depends on it. For this reason, we have synthesized several chlorobenzanthrones. Although 3- and 4-chlorobenzanthrone were prepared by direct chlorination of benzanthrone and by glycerol condensation of 2-chloroanthraquinone, respectively, the synthesis of 1- and 2-chlorobenzanthrone has not yet been successful. In the present study, we attempted to synthesize them by use of the Sandmeyer reaction. First, we nitrated benzanthrone with nitric acid; 1- and 2-nitrobenzanthrone were obtained by nitration in nitrobenzene at 50-60° and in glacial acetic acid at 105-110°, respectively. Then the nitroderivatives were reduced to corresponding aminoderivatives; the reduction was performed with sodium sulfide for 1-nitrobenzanthrone and with hydrogen chloride and tin for 2-nitrobenzanthrone. Finally, chlorination was carried out by use of the Sandmeyer reaction. The products were separated and purified by column-chromatography. The position of chlorination was confirmed by NMR spectroscopy.     

Development of Multi-extreme ESR Measurement System in Kobe

Development of multi-extreme electron spin resonance (ESR) measurement system is in progress in Kobe. We have installed the pulsed magnetic field up to 55 T and our high field ESR system can cover the frequency region from 30 GHz to 7 THz. Our aim is to extend our high field ESR system to the multi-extreme ESR measurement system by combining low temperature, high pressure and nano techniques, and the combination with the high pressure is focused in the paper. High pressure can be achieved up to 1.4 GPa by using the transmission type piston cylinder pressure cell. We have succeeded in combining the high field and the high pressure. As an example, the pressure dependence of the spin gap in SrCu₂(BO₃)₂, S=1/2 Shustally-Sutherland dimer system, observed by our multi-extreme ESR measurement is presented. This measurement is the direct and precise measurement of the spin gap, and the spin gap decreased from 723 GHz (34.7 K) to 581 GHz (27.9 K) at 1.2 GPa.     

Ultrastructure of immotile spermatozoa obtained from infertile male patients

We sometimes experienced infertile patients whose sperms had no motility but were not stained by Eosin Y. In this paper we report five cases of so-called "immotile spermatozoa". The ultrastructure of sperm tails was examined by transmission electrone microscope (TEM). These cases were selected from the out-patient population who attended infertility clinic of our department. The semen analyses showed that all the cases had sperm motility below 1% and more than 90% of the spermatozoa were proven alive. Family history revealed that one case had an infertile sibling. None of them had situs inversus, bronchiectasis and chronic sinusitis which are classic trias of Kartagener's syndrome. They had no symptoms of upper respiratory tract infection which was caused by the abnormality in the flagella of the respiratory tract. The TEM pictures of sperm tails showed partial deletion of inner dynein arms in two cases, lack of central microtubular doublets (so-called 9 + 0) in two cases and disarrangement of microtubular doublets in one case. For the treatment of these cases there is no effective means but AID. However, the rapid progress of IVF-ET techniques and a report that the spermatozoa from Kartagener's syndrome had showed penetration into eggs encouraged us to think the micromanipulation of spermatozoa with IVF-ET as a hopeful option of the treatment in the near future.     

Thermoelectric properties of porous SiC/C composites

We developed a porous SiC/C composite by oxidizing a SiC/C composite made from a mixed powder of wood charcoal and SiO₂ (32–45 μm) by pulse current sintering at 1600 and 1800 °C under a N₂ atmosphere. The microstructures of the porous SiC/C composites with oxidation and the SiC/C composites without oxidation were analyzed by Raman spectroscopy and scanning electron microscopy (SEM). Raman spectra revealed the disappearance of excess carbon and the presence of β-SiC. The porous microstructure was monitored by SEM observation as a function of the heat treatment temperature. The thermoelectric properties of porous SiC/C composites with oxidation and SiC/C composites without oxidation were investigated by measuring the Seebeck coefficient, the electrical conductivity and thermal conductivity. The Seebeck coefficient of all samples revealed n-type conduction, and the absolute value of the Seebeck coefficient for the porous SiC/C samples with oxidation was much larger than that for the SiC/C samples without oxidation. For the electrical conductivity the reverse is true. Only the thermal conductivity of the SiC/C sample heated to 1800 °C without oxidation was high initially and stayed rather high. In general, the thermoelectric properties improved at higher measurement temperatures indicating their suitability for high-temperature thermoelectric conversion. A maximum figure of merit of 2.01×10⁻⁵ K⁻¹ was obtained at 700 °C in porous SiC/C samples sintered at 1800 °C with oxidation.     

The effectiveness of interferon therapy on occurrence of hepatocellular carcinoma in chronic hepatitis C

To clarify the effect of interferon (IFN) therapy for chronic hepatitis C (CHC) on the occurrence of hepatocellular carcinoma (HCC), 149 patients who were observed over a period of five years (mean: 7.6 years) were studied. The C-1 group, 33 patients with complete response to IFN; the C-2 group, 55 patients with no response to IFN; and the C-3 group, 61 patients who did not receive IFN. The occurrence rate of HCC was 0.9%/year/person. In the C-1, C-2 and C-3 groups, the rates were 0%, 0.3%, and 1.6%, respectively. The rate in C-1 + C-2 groups was significantly lower than that of the C-3 group (P<0.05). These data suggest IFN may suppress the occurrence of HCC in CHC.     

Effects of classifier structures and training regimes on integrated segmentation and recognition of handwritten numeral strings

In integrated segmentation and recognition of character strings, the underlying classifier is trained to be resistant to noncharacters. We evaluate the performance of state-of-the-art pattern classifiers of this kind. First, we build a baseline numeral string recognition system with simple but effective presegmentation. The classification scores of the candidate patterns generated by presegmentation are combined to evaluate the segmentation paths and the optimal path is found using the beam search strategy. Three neural classifiers, two discriminative density models, and two support vector classifiers are evaluated. Each classifier has some variations depending on the training strategy: maximum likelihood, discriminative learning both with and without noncharacter samples. The string recognition performances are evaluated on the numeral string images of the NIST special database 19 and the zipcode images of the CEDAR CDROM-1. The results show that noncharacter training is crucial for neural classifiers and support vector classifiers, whereas, for the discriminative density models, the regularization of parameters is important. The string recognition results compare favorably to the best ones reported in the literature though we totally ignored the geometric context. The best results were obtained using a support vector classifier, but the neural classifiers and discriminative density models show better trade-off between accuracy and computational overhead.     

PHoM – a Polyhedral Homotopy Continuation Method for Polynomial Systems

PHoM is a software package in C++ for finding all isolated solutions of polynomial systems using a polyhedral homotopy continuation method. Among three modules constituting the package, the first module StartSystem constructs a family of polyhedral-linear homotopy functions, based on the polyhedral homotopy theory, from input data for a given system of polynomial equations f(x)=0. The second module CMPSc traces the solution curves of the homotopy equations to compute all isolated solutions of f(x)=0. The third module Verify checks whether all isolated solutions of f(x)=0 have been approximated correctly. We describe numerical methods used in each module and the usage of the package. Numerical results to demonstrate the performance of PHoM include some large polynomial systems that have not been solved previously.AMS Subject Classification: Primary: 65H10 system of equations, secondary: 65H20 global methods, including homotopy approaches.