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The international issue to be addressed towards realizing a low-carbon society is to reduce the amount of carbon-based underground reserves such as coal, petroleum, and coke, and strongly encouraged to use carbon neutral biomass-derived resources. Woodceramics is a hybrid porous carbon material composed of wood-based biomass and phenolic resin, characterized by high far-infrared emissivity and large specific surface area. Woodceramics has been studied as heating elements and humidity and gas sensors, etc. If this is applied to the inner walls of aging and grain drying furnaces for vegetables and fruits, both ripening and drying are greatly promoted and fossil fuels used in boilers can be significantly reduced. In fact, it can produce black garlic with far infrared rays using a woodceramics brick efficiently. Furthermore, as a substitute for phenolic resin, if plant-based liquefied materials from cashew nut shell oil can be prepared and can be used for manufacturing woodceramics, then all carbon neutral circulating woodceramics made from wood-based biomass is possible to manufacture. On the other hand, woodplastics is a composite material that can be made of wooden materials and plastics, and able to expect the effective use of wood-based biomass and waste plastics.

We produced Wood-Polymer Composites (WPCs) with phenolic resin (PR) filled with saw dust (SD) and rice husks (RH) in a PR:fillerratio of 60:40 wt.%. RH and SD were grinded and sieved into particles

The term woodceramics is the generic name for carbon materials made of plant originated materials impregnated with phenol and carbonized under reduced pressure of 200 to 2000°C. The inside of woodceramics is porous and they exhibit various properties when the carbonaization temperature is changed. Currently, woodceramics are attracting attention as materials used for humidity sensors, electromagnetic shielding materials, far-infrared heaters and various gas sensors. As such, woodceramics have many characteristics. However, they are stiff, brittle, difficult to process and they tend to crack or chip during processing. Moreover, woodceramics have a tendency to increase in hardness as the carbonaization temperature rises and their processing characteristics differ according to the carbonaization temperature. In our experiment, we used woodceramics, which were made from MDF produced at carbonaization temperatures between 500 and 1200°C, to study the processing characteristics when a blade is used at different carbonaization temperatures. The following are the results. (1) The cutting force is proportional to the carbonaization temperature. (2) Woodceramics carbonized at high temperatures above 1000°C have a tendency to chip more than WCS fired at low temperatures between 500 and 650°C. (3) The continuous-type #300 wheel is best for cutting woodceramics. (4) The surface roughness of woodceramics does not depend on the processing speed at carbonaization temperatures above 1000°C. However, the surface roughness of woodceramics carbonized at temperatures below 800°C greatly depends on the processing speed.

Woodceramics, a carbon/carbon composite of plant-originated carbon reinforced by glassy carbon from phenolic resin, was prepared from apple pomace at carbonizing temperatures of 1073 K (AWC800) and 1473 K (AWC1200), and characterized by thermoanalytical methods and X-ray diffraction (XRD). Simultaneous differential scanning calorimetry (DSC) and thermogravimetric (TG) showed complicated overlapping reactions similar to those of coal. The initial temperature of pyrolysis was obtained by fitting logistic functions to observed TG data. The results suggested that AWC1200 contained more volatile matter than AWC800. In an inert atmosphere, complicated devolatilization takes place. In an oxidizing atmosphere, thermal change occurs roughly in four steps: desorption of physically adsorbed matter; pyrolysis into aliphatic and aromatic fragments; ignition; combustion of char. The oxidation resistance of AWC1200 was superior to AWC800.

Synthesis of morph-genetic materials derived from biological structures by rapid, high temperature conversion represents a novel technology of advanced materials processing. The resulting morph-genetic materials exhibit unique macro- and microscopic cellular morphologies. In addition, based on the porous character of some natural plants, there is a further possibility of compounding the resulting morph-genetic materials with molten metal or polymer to produce morph-genetic composites with interpenetrating networks. Thus, the morph-genetic materials will be endowed with new use values, such as good mechanical properties, and friction behaviors, etc.

An odorless woodceramics (CH800), which was prepared by carbonizing chicken wastes with phenolic resin, was characterized by XRD and thermal analysis. CH800 was found to consist mainly of amorphous carbon (non-graphitizing carbon) as studied by XRD. Differing from carbonized chicken waste, CH800 was completely free of unfavorable smell. The source of strong smell of carbonized chicken waste was studied by using TG-DTA combined with EGA technique using gas chromatography and mass spectrometry (TG-DTA/GC-MS). As a result, it was found that CH800 was completely free of compounds having strong smell, i.e., ethanol, acetonitrile, pyridine, styrene, benzonitrile and benzofuran, whereas carbonized chicken waste contained all of these compounds.

Gas adsorption properties of woodceramics prepared from cedar (Cryptomeria japonica, abbreviated as CE), apple waste (AP), and chicken waste (CH) were studied. Depending on the starting material, woodceramics differed in physisorption properties as evaluated by specific surface area (SSA) obtained by BET (Brunauer–Emmett–Teller) method, in pore structure and size, and in chemical adsorption properties for perfumery substances. CH and AP yielded lower SSA as compared with CE, however, they showed higher gas selectivity for oxygen vs nitrogen gas molecules. The adsorption ability of CE on perfumery essential oil components was evaluated for the first time using the rapid measuring method for VOCs; i.e., the adsorption capacity of cedar-based woodceramics for perfumery materials (essential oil extracts: carvone, pulegone, geraniol, citronellol, menthone, nerol, and citral) was examined. CE showed particularly strong affinity with geraniol and citral, in which more than 99.9% of the compounds were adsorbed. About 99.7–99.8% of pulegone and menthone, 99.0% of nerol, 97.9% of carvone, and 94.0% of citronellol were adsorbed by CE. The adsorption affinity was also influenced by the particle size; particles coarser than 4.0 mm in size showed stronger adsorption.

Woodceramics are carbon–carbon composites produced by impregnating plant-origin lignocellulosic materials with phenolic resin and by carbonizing the resulting precursor at temperatures higher than 650 � C. Since the electric resistance of the woodceramics changes as a function of the carbonizing temperature, heating elements for use in biological incubator systems can be prepared by controlling the electric resistance to obtain optimal Joule heat. Woodceramic heating blocks carbonized at temperatures lower than 800 � C were found preferable from the viewpoint of lower water absorptivity. Then, woodceramic test specimens (310 � 52 � 18 mm 3 ) were produced from medium density fiberboard (MDF) at carbonizing temperatures of 650, 700, 750, and 800 � C (which are simply denoted as 650, 700, 750, and 800, respectively). The electric resistance of the test specimens 650, 700, 750, and 800 at applied voltage of 10 V was 50, 10, 8, and 4 � , respectively. Thus, single test piece of 650, 3 serially connected 700, 7 serially connected 750, and 10 serially connected 800 were used to obtain the temperature profile. Temperature rise of each test specimen was measured under applied voltages of 10, 20, 30, and 40 V. For 650, fair temperature stability was obtained at 22 � C (10 V) and 27–31 � C (20 V). The advantages of the woodceramic heaters as compared with the conventional ceramic heaters are: (1) quick rise in temperature; (2) high stability at designated temperature; (3) lower power consumption; and (4) free of air convection (heats the sample directly and homogeneously).

Systematic morphological observations and surface analyses were completed in order to clarify the surface structure of ‘‘woodceramics’’, i.e., carbon-carbon composite materials consisting of plant-originated carbon reinforced by carbon generated from phenol resin. The woodceramics manufactured from cedar sawdust at various temperatures (650, 700, 800, 1000 and 1200C) in a nitrogen atmosphere were examined. The microstructure was not affected by the manufacturing temperatures; bundles of the micro-tubes of the original plant (cedar) were preserved. The nanostructure was also unaffected by the manufacturing temperatures except for the one manufactured at the highest temperature (1200C). Fine needles (fibers) on the surface of the 1000C-prepared specimen were incorporated into the substrate for the 1200C-prepared specimen. The oxygen/carbon atomic ratio (0.14) determined by XPS was approximately constant for all specimens manufactured at various temperatures. This value agreed with that of the bulk composition (0.12) except for the one (0.07) manufactured at the highest temperature (1200C). The binding energy of C1s (284.1 eV) was attributed to elementary carbon. The binding energies of C1s and O1s (532.4 eV) were unchanged by the manufacturing at different temperatures. The specimens manufactured at low temperatures (650, 700 and 750C) showed high hydrogen/oxygen atomic ratios (2.6, 2.0 and 1.9, respectively) while those manufactured at high temperatures (1000 and 1200C) had the lower values (1.3 and 1.4, respectively). The X-ray diffraction analysis indicated an amorphous phase with weak hallos at 23.7 and 43.1 (d-spacing; 0.375 and 0.210 nm, respectively). The weak peaks at 30.41, 35.30 and 50.84 (d-spacings; 0.2937, 0.2541 and 0.1795 nm

Beta-dolabrin, gamma-thujaplicin, and 4-acetyltropolone, the components of Aomori Hiba (Thujopsis dolabrata SIEB. et ZUCC. var. hondai MAKINO), showed antifungal activity on seven kinds of plant-pathogenic fungi, antibacterial activity against two kinds of Legionella sp., and in vitro cytotoxic effect on murine P388 lymphocytic leukemia cell line. Firstly, beta-dolabrin, gamma-thujaplicin and 4-acetyltropolone had clear antifungal activity against seven kinds of plant-pathogenic fungi tested. In particular, beta-dolabrin and 4-acetyltropolone showed strong antifungal activity against Pythium aphanidermatum IFO 32440, with minimum inhibitory concentration (MIC) values of 6.0 microg/ml. Secondly, beta-dolabrin, gamma-thujaplicin and 4-acetyltropolone had obvious growth-inhibitory effect on two kinds of Legionella sp. 4-Acetyltropolone especially had strong antibacterial activity toward Legionella pneumophila SG 1, and its MIC value was 3.1 microg/ml. These three compounds showed cytotoxic effects against murine P388 lymphocytic leukemia cell line in vitro. The cytotoxic effect of three compounds in the murine P388 lymphocytic leukemia cell line were clear when cell growth was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. At 48 h after treatment, gamma-thujaplicin and 4-acetyltropolone at 0.63 microg/ml inhibited cell growth of murine P388 lymphocytic leukemia by 85% and 65%, respectively. At the same time after treatment, the growth of the murine P388 lymphocytic leukemia cell line was completely suppressed by the three compounds at concentrations higher than 5.0 microg/ml. Among these three compounds, gamma-thujaplicin had the strongest cytotoxic activity on the growth of this tumor cell line in vitro.

Background and Objective The aim of this study is to know whether intravenous digital subtraction angiography (IV-DSA) is useful to detect axillary lymph node metastasis of breast cancer and to evaluate the anigiogenesis of lymph nodes in the axilla. Patients and Methods Forty three primary breast cancer patients (N0: 26 cases, N1: 5 cases, N2: 2 cases) who underwent IV-DSA between January and November 2000 were included in the study. Infinix CB apparatus (Toshiba, Japan) was used to collect IV-DSA images and when a mass became stained in the axilla, it was considered to be metastatic. The angiogenesis was studied by examining microvessel density (MVD) after lymph node immunostaining for factor VIII. Primary tumor was detected by IV-DSA in all 43 cases. Results Axillary lymph node metastases were detected by IV-DSA in 34.9% of cases (15/43), and by pathology in 37.2% (16/43). The sensitivity, specificity, and accuracy of the diagnostic method were 75.0% (12/16), 88.9% (24/27), and 83.7% (36/43), respectively. MVD, calculated after immunostaining for factor VIII, was significantly lower in the in metastatic region of lymph nodes identified by DSA (88.5 ± 35.0) than in metastasis-free lymph nodes (141.1 ± 34.0, P

alpha-Thujaplicin, a minor component of Aomori Hiba (Thujopsis dolabrata SIEB. et ZUCC. var. hondai MAKINO), showed rather strong antifungal activity against seven kinds of plant-pathogenic fungi, their minimum inhibitory concentrations (MICs) being in the range of 12.0-50.0 microg/ml. alpha-Thujaplicin and hinokitiol (the major component of Aomori Hiba) also showed clear antibacterial activity against Legionella pneumophila SG 1 and L. pneumophila SG 3, and their MICs are in the range of 6.25-50 microg/ml. This compound showed strong insecticidal activity against Reticulitermes speratus [50%-lethal concentration (LC(50)): 0.02 g/m(2)], and it also had clear acaricidal activity against Dermatophagoides farinae (LC(50): 0.66 g/m(2)). At 24 h after treatment, alpha-thujaplicin at 0.63 microg/ml inhibited the cell growth of murine P388 lymphocytic leukemia by 78%, and its cytotoxic activity at a concentration higher than 0.63 microg/ml was as high as that of vincristine, used as a positive control. On the other hand, the cytotoxic effect of alpha-thujaplicin at 0.63 microg/ml was weaker than that of vinblastine. In this respect, the strong cytotoxic effect of alpha-thujaplicin on murine P388 lymphocytic leukemia cell line should be emphasized, considering that it has recently been found to be low in toxicity to mice.

Wood is a natural material with a novel and ordered hierarchical structure. In the present work, it is used as a bio-template to produce morph-genetic TiC/C ceramics. This is obtained by infiltrating the carbon preform pyrolyzed from wood with tetrabutyl titanate. It was subsequently sintered at 1400 °C to produce the final ceramic structure. By observing the microstructure under the scanning electron microscope and the transmission electron microscope, the morph-genetic TiC/C ceramics are shown retaining the complex morphology of the original template structure. The crystalline TiC was formed through the reaction of tetrabutyl titanate with carbon preform, and it was distributed mainly at the surface layer of the cellular wall. During the conversion of wood into carbon preform, the specific surface area of samples increased from 28.2 to 35.7 m 2 g −1 , and its porosity also increased from 64.4% to 80.3%. However, during the conversion of carbon preform into morph-genetic ceramics, the specific surface area of samples decreased from 35.7 to 33.8 m 2 g −1 , and its porosity also decreased from 80.3% to 76.5%. At the synthesis process, the variation of pore-size distribution is mainly in the range from 0.1 to 1 μm.

Ecoceramics is a porous carbon material which is proved to have some favorable characteristics. With the purpose of enlarging the application fields of ecoceramics, an ecoceramics/ZK60A (ECMs/ZK60A hereafter) composite was fabricated using high-pressure vacuum infiltration technique. Microstructural analysis and measurements of mechanical properties as well as damping behavior of ECMs/ZK60A composite were made. Experimental results show that ZK60A filled most of the pores and ECMs/AlSi composites have a topologically uniform interconnected network microstructure. ECMs/ZK60A composite exhibited superior mechanical properties as compared with uninfiltrated ecoceramics. It is believed that strengthening effect was caused by strengthening of ZK60A, crack bridging by the ductile phase and interlocking structure between components in ECMs/ZK60A composite. Damping values of ECMs/ZK60A composite improve based on those of ecoceramics. They increase with testing temperature but decrease with increasing vibration frequency.

Woodceramics/AlSi (WCMs/AlSi hereafter) composites were prepared by means of high-pressure vacuum infiltration of liquid alloy into woodceramics. The friction and wear behavior of WCMs/metal composites at various applied loads and sliding velocities was investigated by using a block-on-ring test at room temperature under dry conditions. Furthermore, the morphologies, phases and element valences of the worn surface and debris were observed, examined and analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray microanalysis (EDAX) and X-ray photoelectron spectroscopy (XPS), respectively. In addition, load and sliding velocity dependence mechanisms of the wear and friction behavior of the composite and matrix alloy were discussed. Experimental results show that WCMs/AlSi composites have a topologically uniform interconnected network microstructure. Their tribological properties are improved dramatically, compared to those of the matrix AlSi alloy, due to the formation of wide, compacted surface carbon films. The wear mechanisms of WCMs/AlSi composites and of the matrix alloy vary with applied load from mild to severe wear.

Tropolone (1). showed strong insecticidal activity on Tyrophagus putrescentiae and Dermatophagoides farinae. The insecticidal effect of 1 on both insects was stronger than that of hinokitiol (2, 4-isopropyltropolone: major component of Thujopsis dolabrata SIEB. et ZUCC. hondai MAKINO). The insecticidal activity of both compounds was higher than that of N,N-diethyl-m-toluamide (DEET), used as a positive control. Compound 1 had potent insecticidal activity against Coptotermes formosanus, although its activity was much lower than that of commercial chloropyrifos. Like 2, 1 showed the inhibitory activity toward metalloproteases such as carboxypeptidase A, collagenase and thermolysin and their inhibitory activities were much higher than that of 1,10-phenanthroline, used as a positive control. The inhibitory activity of 1 on carboxypeptidase A was especially high, its 50% inhibitory concentrations (IC(50)) being 2.73 x 10(-6) M. This inhibitory activity was as high as that of 2 (IC(50): 2.76 x 10(-6) M). Compound 1 inhibited the growth of seven kinds of plant-pathogenic fungi and their minimum inhibitory concentration (MIC) values were in the range of 6.0-50.0 microg/ml. In particular, 1 showed strong antifungal activity on Pythium aphanidermatum IFO-32440 (MIC: 6.0 microg/ml).

Intravenous digital subtraction angiography (IV-DSA) was performed before and after neoadjuvant chemotherapy (NACT) in five patients with locally advanced breast cancer, and the efficacy of NACT was evaluated on the basis of the results of IV-DSA and histopathological examination. Following NACT, the maximum density of tumor enhancement (MAX) in the IV-DSA image decreased by 61.6% in case 1, 50% in case 2, 58.1% in case 3, 90.8% in case 4, and 97.2% in case 5. In all five patients, the efficacy of chemotherapy was rated as a partial response in terms of tumor size, while histological efficacy was rated as slightly effective in cases 1-4 and moderately effective in case 5. The pathological efficacy of NACT was highest in case 5, which showed the greatest decrease in MAX. These results indicate that variations in MAX reflect clinical efficacy, and, to some extent, also permit prediction of pathological efficacy.

Woodceramics have attracted more and more attention as ecomaterials at low cost in recent years. With the purpose of enlarging the application fields of woodceramics, woodceramics/Al (WCMs/Al hereafter) and woodceramics/AlSi (WCMs/AlSi hereafter) composites were fabricated using high-pressure infiltration of a pure aluminum and aluminum alloy into vacuum woodceramics. The microstructural analysis showed that metal filled most of the pores and WCMs/metal composites had topologically uniform microstructure. The fabricated materials exhibited superior compressive strength and bending strength when compared with uninfiltrated woodceramics. SEM micrographs of fracture surfaces of composites showed deformed metal ligaments which demonstrated that crack bridging by plastic deformation of metal phase is one of the toughening mechanisms.

Structural inspection of carbonized woodceramics impregnated with liquefied wood was performed by dimensional shrinkage and weight loss, the content of carbon and oxygen with X-ray energy dispersive analysis (EDS), Raman scattering spectroscopy, laser microscope observation and X-ray diffraction. The results showed that with the increasing temperature, the dimensional shrinkage, weight loss and the ratio of carbon to oxygen in woodceramics increased, the (002) interplanar spacing of the crystalline component in woodceramics decreased and the value of R increased above 650°C. Woodceramics have a turbostratic structure with cracks, and internal stresses etc., especially for those carbonized at temperatures over 650°C.

症例は70歳,男性.血便の精査目的にて当院を受診した.大腸内視鏡検査にて下行結腸に長径4cmの太い茎を有する有茎性ポリープを認めた.内視鏡的切除は困難と判断し,下行結腸部分切除術を施行した.ポリープは主として粘膜と粘膜下層から成っており,表面は一部に潰瘍形成や過形成性の変化を認めるものの,ほとんどが正常粘膜で覆われていた.また粘膜下層は線維化と血管の増生を認めるのみであった.以上よりcolonic muco-submucosal elongated polyp (CMSEP)の概念に一致するポリープと思われた.自験例では粘膜・粘膜下層のみならず,筋層の一部が茎部に向かって引き延ばされており,本疾患に対する内視鏡的治療には注意を要すると考えられる.

Woodceramics has attracted more and more attention as ecomaterial at low cost in recent years. The purpose of this paper is to investigate morphology, damping characteristics of woodceramics and relationship between them. The experimental results reveal that pores in woodceramics can be divided into macropores, micropores and nanopores according to their dimensional size. Macropores are the majority of interconnected pores while most micropores are closed pores. Based on formation process, nanopores are supposed to consist of isolated nanopores and dendritic nanopores. Woodceramics exhibits significant damping gains, especially at room temperature, higher strain amplitude and higher vibration frequency. The values of damping capacity increase with vibration frequency and strain amplitude, decrease with testing temperature. Macropores and some nanopores have little but micropores and some other nanopores have much contribution to damping properties of woodceramics. The possible damping mechanisms of woodceramics at normal temperature are defect damping and thermoelastic damping; at high temperatures, interface damping is likely to responsible for the majority of the damping of woodceramics.

4-Acetyltropolone, a minor component of Thujopsis dolabrata SIEB. et Zucc. hondai MAKINO, showed antimicrobial activity against various microorganisms including wood-rotting fungi, a phytogrowth-inhibitory effect with chlorophyll biosynthesis inhibition, cytotoxic effect and inhibitory activity on metalloproteases. This compound had strong antifungal activity on Daedalea dickinsii IFO-4979 [minimum inhibitory concentration (MIC): 0.2 microg/ml] and Coriolus versicolor IFO-4940 (MIC: 0.39 microg/ml). Its cytotoxic effect at 20.0/microg/ml on human stomach cancer KATO-III and Ehrich's ascites carcinoma was stronger than those of podophyllotoxin, vincristine and vinblastine, the anticancer agents isolated from higher plants and used clinically. This compound also had potent antibacterial activity against Staphylococcus epidermidis IFO-12993, its MIC being 1.56 microg/ml. However, other biological activities of 4-acetyltropolone were lower than those of hinokitiol which is the main component of this plant, suggesting that the contribution of the acetyl group at C-4 to biological activity is smaller than that of the isopropyl group at that position. The acute toxicity of 4-acetyltropolone (LD50: 335.2 mg/kg) to mice was much lower than that of hinokitiol (LD50: 191 mg/kg).