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Energy-controlled and mass-selected beam of fluorocarbon ion (CF3+,CF2+) at energies from 50 to 400 eV are directed at Si and SiO2 surfaces, in order to elucidate etch mechanisms and SiO2/Si etch selectivity. During the ion beam injection, the time evolution of neutral radicals desorbed from the etching surface is measured by appearance mass spectrometry. At the same time, in situ surface analysis is also carried out by x-ray photoelectron spectroscopy. The etching rate of a clean Si surface by CF3+ injection is initially high but decreases with time due to the formation of a thin surface layer containing F and C atoms. Finally, a few-nanometers-thick stationary SixCyFz overlayer is formed on the Si surface for ion fluence >3×1016 cm−2, along with saturation of CF2 and SiF2 radical desorption from the surface. Comparison is made with molecular dynamics simulations of CF3+ interactions with Si surfaces. CF2+ injection on the Si surface yields rapid formation of the SixCyFz layer and lower desorption of the...

We investigated genetic diversity among and within natural populations of Asian common wild rice, Oryza rufipogon, from three different classes of data: quantitative traits, allozymes, and restriction fragment length polymorphisms (RFLPs). The seven populations examined showed polymorphism to varying degrees. The amount of intrapopulation variability appeared to be influenced not only by breeding system but also by the evolutionary history of each population. Interpopulation differentiation was clear, but different classes of data elucidated different patterns. Quantitative traits revealed ecotype differentiation into perennial and annual types of population, whereas allozyme and RFLP analyses revealed geographical differentiation among populations. These results suggest that the diversity patterns shown by quantitative trait analysis reflect mainly the occurrence of adaptive differentiation in response to habitat conditions and that those shown by allozyme and RFLP analyses reflect mainly the effect of isolation by distance. Population differentiation parameters (F(ST)) were highly variable among loci in allozymes as well as in RFLPs.

The pan-tropical wild relatives of rice grow in a wide variety of habitats: forests, savanna, mountainsides, rivers and lakes. The completion of the sequencing of the rice nuclear and cytoplasmic genomes affords an opportunity to widen our understanding of the genomes of the genus Oryza. Research on the Oryza genus has begun to help to answer questions related to domestication, speciation, polyploidy and ecological adaptation that cannot be answered by studying rice alone. The wild relatives of rice have furnished genes for the hybrid rice revolution, and other genes from Oryza species with major impact on rice yields and sustainable rice production are likely to be found. Care is needed, however, when using wild relatives of rice in experiments and in interpreting the results of these experiments. Careful checking of species identity, maintenance of herbarium specimens and recording of genebank accession numbers of material used in experiments should be standard procedure when studying wild relatives of rice.

Control of lamellar orientation in unidirectionally solidified Ti-48Al PST crystals has been attempted by an optical floating zone method using various seed crystals of Ti-(48-57)Al alloys. Regardless of the seed crystals, the Ti-48Al PST crystals can be grown without any difficulty. However, the lamellar orientation can never reproducibly be controlled by using any seeds but single crystal of Ti-57Al. In case of the 48Al PST seed, polycrystallization due to γ→α phase transformation takes place in heating to melt. The seeds with composition range of a peritectic reaction (L+α→γ) to occur in melting exhibit a cellular liquid/solid interface, resulting in new grains there. In these cases, the grown crystal follows an orientation of one of the newly formed grains. The single crystal seed of Ti-57Al exhibits a flat liquid/solid interface in melting (γ→γ+L) even after making contact with 48Al alloy to grow, and the grown crystal follows the seed orientation. It is concluded that composition travel to skip the peritectic reaction (L+α→γ) using γ single phase seed makes the control of lamellar orientation of PST crystals possible.

Numerical calculations have been done to reveal temperature distributions and cooling speeds of laser-heated samples in a diamond anvil cell. The distributions were calculated for variable experimental parameters including the diameter of the laser beam, anvil gap, and sample. The results show that the radial temperature distribution in all samples is Gaussian. The axial temperature gradient is ∼10 K/μm in samples heated by a broad laser beam of 100 μm diameter, and is ∼102 K/μm when a narrow laser beam of 10 μm diameter is used. The broad beam can generate a less extreme temperature gradient in both radial and axial directions as compared with the narrow beam, whereas the temperature gradient strongly depends on the anvil gap, although this is minimized when a narrow beam is used. When the narrow beam is used to heat samples, the surface temperature of the anvil culet can be kept below 400 K; thus, the narrow beam is suitable for heating samples under high pressure while keeping anvil temperatures low. C...

To clarify the value of clinical long-term follow-up with radiological examination, ranging from 12 to 63 months (average: 35 months), 18 consecutive patients suffering from spontaneous carotid cavernous fistula (CCF), were studied prospectively. Five aged patients without aggressive symptoms were treated conservatively, and the other 13 underwent transarterial embolization. The radiological follow-up was primarily by magnetic resonance angiography (MRA), performed from 2 to 6 times (average: 4.1 times) during the follow-up period. In three cases, CCFs persisted, but the other fifteen (83%) demonstrated complete cure as defined by long-term follow-up MRA. The three patients with persistent CCFs were comparatively young, less than 60 years old, had no atherosclerotic factors and demonstrated multiple venous drainage routes with cortical venous drainage on angiography. In two of them, the symptoms completely disappeared, and the other had only mild chemosis. However, surprisingly, in two, MRA revealed residual CCF with drainage into only cortical veins through the sphenoparietal sinus, this radiological finding being well known to signify danger. During the follow-up period, central retinal vein thrombosis occurred in two cases. The common point in these cases was that the superior ophthalmic vein was the only venous drainage route. This is also a point requiring care. We therefore emphasize the importance of careful long-term radiological follow-up for spontaneous CCF patients even when their symptoms improve or disappear. MRA is particularly suitable for this purpose and applicable in the out-patient clinic because of its non-invasive nature.

A 37-year-old female with left sided multiple congenital haemangiomata presented with repeated haemorrhage. The haemorrhagic origin was from the angiomatous lesion with arteriovenous (AV) shunting in the tongue and pharynx. The patient had already undergone ligation of the external carotid artery. Vascularization was mainly from the portion of the external carotid artery distal to the occlusion. Our first approach via the collateral channels to the haemangioma failed. Through direct puncture of the distal end of the external carotid artery with the use of two dimensional road mapping, we succeeded in catheterizing the distal end of the external carotid artery at the first attempt without placing any pressure on the neck, and carried out selective embolisation without mishap.

Effectivness of the hybrid-weakness caused by a complementary interaction of two dominant genes Hwc1 and Hwc2 to suppress the spread of the red-grain gene into ordinary white-grained rice cultivars was investigated using the Monte Carlo computer simulation method. It was shown that the weakness genes, as far as being capable of reducing the fitness of the carrier by 80 percent or more, work quite effectively to suppress the genetic contamination of white-grained cultivars due to inflow of pollen from red-grained cultivars due to inflow of pollen from red-grain gene once the gene has been incorporated in to the population in the form of red-grained progeny produced as a result of the imperfect lethality of the initial hybrid between red-and white-grained cultivars. The weakness genes have little or no effect cultivars. The weakness genes have little or no effect either, when the contamination is initiated by an inflow of seeds or seedlings from ed-grained cultivars in these situations, removal (selection)of red grained plants Is the only countermeasure to exterminate the red-grain gene. The removal of red grained plants need not be intensive if carried out continuously. The spread of the red-grain gene after initial contamination is suppressed if the red-grain gene and weakness genes are linked. The suppressing effect of the linkage, however, is not substantial when the outcrossing rate is around or smaller than 0.01 as can be assumed in most rice cultivars.

Graphite samples are heated in a diamond anvil cell with a CO2 laser above 11 GPa. A light transparent phase has appeared after heating, which is quenchable at ambient conditions. The Raman spectrum shows that the phase is a fine-grained cubic diamond. Images by a high resolution transmission electron microscope indicate that the diamond has twins and stacking faults of nanometer size. The electron diffraction pattern shows that the stacking fault cannot be explained by a diamond polytype such as a hexagonal diamond. The cathodoluminescence pattern exhibits the “band-A” emission, which is derived from the defects of the cubic diamond.

Atomic force microscopy (AFM) has been applied to the analysis of CR-39 nuclear track detectors for high dose neutron dosimetry. As a feasible study to extract the neutron dose, we have employed a (239)Pu-Be neutron source with the traditional track density measurement of recoil proton etch pits from a high density polyethylene (CH(2)) radiator. After very short etching ( approximately 1 microm), etch pit densities were measured as a function of neutron fluence (neutron dose) up to 1.4 x 10(10) cm(-2) (6.6 Sv). Neutron sensitivity was also measured to be 6.6 x 10(-4). Maximum measurable neutron dose was estimated to be approximately 200 Sv by measuring the fraction of the total image area occupied by the etch pits.

We report on one Japanese case subject with neurocysticercosis (NCC) who had a single cyst in the brain and had undergone curative surgical resection. Pathological examination revealed that it was a cysticercus of Taenia solium. Serological examination of the pair serum samples just before and 1 year after surgery revealed that antibody responses against the glycoproteins, highly specific to NCC and detected in the serum sample just before surgery by both immunoblot and ELISA became negative within 1 year after the surgery. It is, therefore, strongly suggested that this case had a single cysticercus in his whole body and the presence of a single cysticercus was sufficient to evoke antibody responses against it.

Summary: A 27-year-old man with congenital external carotid–jugular arteriovenous fistula presented with a diminished level of consciousness and an ataxic gait. Axial fluid-attenuated inversion-recovery (FLAIR) MR imaging revealed venous congestion, a dilated right jugular vein, and an area of high signal intensity in the brain stem and cerebellum. Angiography showed a dilated right external carotid artery and jugular vein and the presence of a fistula. After coil embolization of the fistula, axial MR FLAIR images showed only a few areas of high signal intensity in the brain stem and cerebellum. The causal factor was venous congestion in the inferior petrosal sinus and basilar plexus due to high blood pressure in the jugular vein. This case is presented for its unusual clinical and radiologic findings.

Unidirectional solidification of Ti-48Al binary alloy using γ-TiAl single-phase seed crystals has been carried out by an optical floating zone method. The lamellar orientation of the grown PST crystal follows the orientation of the Ti-57Al seed crystal, while it fails to follow that in the case of the Ti-53Al seed. Microstructure analysis reveals that the seed crystal of Ti-57Al exhibits a flat liquid/solid interface in melting (γ→+L) even after making contact with 48Al to grow, whereas the seed of Ti-53Al shows a cellular interface due to the peritectic reaction in melting (γ→α+L). At the 57/48 interface, an abrupt change of Al concentration was detected from the seed to the grown crystal, indicating an occurrence of composition travel to skip the peritectic reaction, which is responsible for the control of lamellar orientation of the grown PST crystals. The same attempt has been made by using the 57Al single crystal seed with a different orientation, and the lamellar orientation of the grown PST crystal was confirmed to follow the orientation of the seed.

J-107088 [6-N-(1-hydroxymethyl-2-hydroxy)ethylamino-12,13-dihydro-2,10-dihydroxy- 13-(beta-D-glucopyranosyl)-5H-indolo[2,3-a]-pyrrolo[3,4-c]-carb azo le-5,7(6H)-dione] is a new derivative of NB-506, an indolocarbazole antitumor agent. J-107088 induced single-strand DNA cleavage only in the presence of topoisomerase I (top1) more effectively than NB-506 or camptothecin. The preferable sequences of the DNA cleaved by J-107088 were C/T / G as in the case of NB-506. This base-preference of J-107088 in top1-mediated cleavage was different from that of camptothecin, which was T / G/A. top1 poisons stabilize the complex between DNA and top1 (cleavable complex). This cleavable complex is released on addition of a high concentration of monovalent cation or removal of top1 poisons. The complex induced by J-107088 was quite stable; it was scarcely released on the addition of NaCl or dilution of J-107088, contrary to the case with camptothecin and NB-506. J-107088-inducing complexes were also stable in cultured cells, when the compound was added to the culture medium. These unique in vitro activities of J-107088 on top1 that differed from those of camptothecin and NB-506 may be relevant to its more potent in vivo antitumor efficacy in a human tumor xenographted nude mouse model.

We report on a case of thymic cyst which was successfully treated with mediastinoscopic resection combined with a sternum lift technique. A 62-year-old man was admitted to our hospital with a thymic cyst, which was causing chest discomfort and was increasing in size. The tumor was located above the pulmonary artery in the anterior mediastinum. He underwent mediastinoscopic resection while lifting the inferior portion of the sternum with a Laparolift. The cyst was resected sharply and bluntly with the Harmonic Scalpel without rupture. The patient was discharged on the 6th postoperative day in a good condition. Mediastinoscopic resection of a thymic cyst through a xiphoid approach is a useful surgical approach because of the absence of postoperative pain and because it allows early discharge from the hospital.

To determine whether the absolute value for the stump pressure might be a useful index of symmetrical cerebral blood flow (CBF), and to examine correlations with the stump pressure ratio (initial mean stump pressure/preocclusion mean arterial pressure), fifty candidates for ICA injury or permanent occlusion were evaluated preoperatively. Each was continuously monitored for mean stump pressure and arterial pressure before, during (for a total of 20 min), and after balloon test occlusion. During the occlusion, CBF was measured by 99 m Tc-hexamethyl-propyleneamine oxime (99 m Tc-HMPAO) single photon emission computed tomography (SPECT). The stump pressure and the stump pressure ratio were then compared with the results of 99 m Tc-HMPAO SPECT. Patients who failed to tolerate even brief periods of carotid occlusion and showed asymmetric decreases in CBF on SPECT were divided into high and moderate risk groups. Those with no significant changes in CBF on the occluded site formed the minimum risk group. Mean stump pressure was over 50 mmHg in 10 of a total of 25 patients in the high and moderate risk groups, and below 50 mmHg in 5 of the 25 patients in the minimum risk group. The stump pressure ratio did not exceed 56% in any but two patients in the high and moderate risk groups, and values were at least 60% in all patients of the minimum risk group. Decrease of CBF in two moderate risk group cases was localized in the posterior circulation. Difference in symmetrical CBF between the stump pressure ratio vs. the absolute value of mean stump pressure were statistically significant (p < 0.01, Fisher's Exact Test). Maintenance of a stump pressure ratio of 60% or more during test occlusion may be a more useful index for a good collateral circulation than any absolute value for mean stump pressure.

We assessed the long-term follow-up results of platinum coil embolization and aneurysmography (ARG) with endovascular surgery for giant aneurysms. 24 cases of giant aneurysms were treated over a period of seven years. In the present study, the 16 of these for which surgical dipping was impossible so that only endovascular surgery was employed were investigated in detail. In 10 cases the cavernous sinus area was involved, in two each the tip of the basilar artery, and the bifurcation of the ophthalmic artery, and in one each the extracranial internal carotid and the vertebral artery. Since conventional angiography did not allow the position and size of the neck of 10 cavernous sinus aneurysms to be identified, making treatment decisions difficult, we applied the ARG developed by the senior author. Prior to treatment, balloon test occlusion of the parent arteries was performed. In all 10 cavernous sinus cases, ARG successfully revealed the morphology of the aneurysm. A small neck was diagnosed for seven of the aneurysms of the cavernous sinus and all those located at the basilar and ophthalmic arteries, making a total of 11, and for these endosaccular embolization was carried out. In the other 5 cases, proximal occlusion using Gold valve balloons was performed. Under ARG, embolization of the aneurysms could be safely accomplished with platinum coils, without dislocation of the coils into the parent arteries in all cases. In four out of 10 cases, re-opening of the aneurysms occurred after 2 months or longer, so that re-embolization was required. Regarding complications, transient monoparesis of the upper extremity was encountered in one case. After angiographic and MRA follow-up of 1–36 months (average, 13.8 months), 4 of 10 cases demonstrated complete occlusion, and 5 displayed an 80–90% reduction in blood flow. In only one case, involving a basilar tip aneurysm, was the treatment unsuccessful in preventing eventual rupture and death. In cases where the morphology of the aneurysm is unclear, ARG can be considered indispensable for determining the treatment modality and safe performance of localized embolization of the neck by endovascular surgery. However, since coils used for embolization of giant aneurysms may move or become compacted, re-opening can occur so that applications may be limited, especially with terminal type lesions with intraluminal thrombus, and the necessity for long-term follow-up must be emphasized.

To understand the genetic basis of floral traits associated with the mating system in rice, we analyzed pistil, stamen and glume traits using a recombinant inbred line population, derived from a cross between an Asian cultivated rice ( Oryza sativa L.), Pei-kuh, and a wild rice ( Oryza rufipogon Griff.), W1944. Quantitative trait loci (QTLs) affecting floral morphology were detected by composite interval mapping using a linkage map constructed using 147 markers, mostly RFLPs. A total of 7, 4, 14 and 6 QTLs were detected for traits related to pistil, stamen, and size and shape of the glume, respectively. Comparison of 31 QTLs affecting these organs revealed ten QTLs affecting the different organs in four adjacent regions on chromosomes 2, 4, 5 and 10, but most QTLs (68%) were located separately on the whole chromosomes. Although four QTLs for stigma breadth, anther length and thickness of lemma and palea explained more than 25% of the total phenotypic variance, most QTLs (87%) had smaller effects. These results suggest that quantitative variation observed for pistil, stamen and glume traits is controlled by several distinct genes with small effects.

Populations of the common wild rice of AsiaO. rufipogon Griff. (=Oryza perennis Moench) were studied with regard to interrelations between life-history traits and habitat conditions. They showed a perennial-annual continuum and differed in reproductive allocation and many other traits. Perennial populations were found in deep swamps, while annual populations were in shallower, temporary swamps which were parched in the dry season. The perennial and annual types tended to be in association with other perennial and annual plants, respectively, suggesting their niche differentiation. Intermediate perennial-annual populations were in communities with a high species diversity. In one population, plants growing on the periphery of the swamp were of annual and those in deeper center were of perennial type. Another population seemed to be differentiated into an annual and an intermediate type in accordance with different degrees of habitat disturbance. The small genetic distances found between the sub-populations suggested their differentiation within a gene pool.

ESR spectra have been observed at room temperature for silicon irradiated by 1012 to 101631P+ ions/cm2 at 190 keV in the 〈111〉 channel direction. Present results show that the relation between the relative number of spins and irradiation dose is not monotonic but has structure in this dose region, and that the total number of spins relatively varies by a factor of only 10 in this region. Es wurden bei Raumtemperatur ESR-Spektren an Silizium beobachtet, das mit 1012 bis 101631P+-Ionen/cm2 einer Energie von 190 keV in der 〈111〉-Kanal-Richtung bestrahlt worden war. Die erhaltenen Resultate zeigen einen nicht-monotonen, strukturierten Zusammenhang zwischen der relativen Anzahl der Spins und der Bestrahlungsdosis in diesem Bereich und weiterhin, das die Gesamtzahl der Spins im gleichen Dosisbereich nur um einen Faktor 10 variiert.

Effect of Eimeria tenella infection on Salmonella typhimurium infection of chickens was tested using feed experimentally contaminated with S. typhimurium. Four experiments were conducted. In Experiments 1 and 2, chickens received feed contaminated with 10(3) or 10(2) cfu of S. typhimurium per g for 5 days after E. tenella infection. In Experiments 3 and 4, chickens were fed feed contaminated with 10(2) or 10 cfu of S. typhimurium per g for 3 days before E. tenella infection. In all experiments, chickens were necropsied 3 to 14 days after E. tenella infection. The number of S. typhimurium in the cecal contents was counted and the presence of the organism in the liver and bile was examined. In Experiments 1 and 2, there was no significant difference in S. typhimurium infection between the group infected with S. typhimurium alone and the group infected with both E. tenella and S. typhimurium. In Experiments 3 and 4, S. typhimurium counts in the cecal contents of chickens in the concurrently infected group were significantly greater than those of chickens in the S. typhimurium alone-infected group.

When silicon substrates are irradiated by 2.5 × 101631P+ ions/cm2 at 190 keV in the 〈111〉 direction, the ESR spectrum showed two resonances (g = 2.0057 and g = 2.0026). The former represents the amorphous state while the latter is a signal which cannot be seen at lower doses. They have different annealing characteristics between 100 and 800 °C. The composition of two independent Lorentzian spectra designed for these g-values can successfully reproduce the experimental spectrum observed after annealing at high temperatures. Wenn Siliziumsubstrate mit 2.5 × 101631P+-Ionen/cm2 bei 190 keV in 〈111〉-Richtung bestrahlt werden, zeigt das ESR-Spektrum zwei Resonanzlinien (g = 2,0057 und g = 2,0026). Die erstere ruhrt vom amorphen Zustand her, wahrend die letztere ein Signal ist, das bei niedrigeren Dosen nicht beobachtbar ist. Sie zeigen unterschiedliche Temperungscharakteristiken zwischen 100 und 800 °C. Die Zusammensetzung von zwei unabhangigen Lorentzlinien mit diesen g-Werten kann das experimentelle Spektrum, das nach der Temperung bei hohen Temperaturen beobachtet wird, erfolgreich reproduzieren.

By ferricyanide oxidation of 2-(4-methoxyphenyl)phenanthro[9,10- d ]imidazole, three new photochromic compounds were obtained. These were 4-ethoxy-4H-, 4-methoxy-4H- and 2-methoxy-2H-phenanthro[9,10- d ]imidazoles. These compounds gave the 2-(4-methoxyphenyl)-phenanthro[9,10- d ]imidazolyl radical and acetaldehyde or formaldehyde by light irradiation. The imidazolyl radical dimerized gradually in the dark and the dimer dissociated to the imidazolyl radical on heating.

To examine genetic variation in the growth curve parameters and their contribution to factors determining grain yield, 40 randomly chosen F 7 lines of a cross between two contrasting rice varieties were measured for dry matter weight and for other yielding characters during the growing period. From the dry weight data, growth curves were computed using linear and quadratic (Pearl-Reed) logistic equations, and various values derived from them were compared among lines. The results showed that: 1) The growth curves of the lines varied genetically between the “early-vigor” and “sustained-vigor” types. 2) Total panicle length per unit area, representing the potentiality for carbohydrates to be produced in grains, seemed to depend on the growth rate at floral initiation, and panicle weight per unit length, representing the rate of carbohydrate supply to the panicles, seemed to depend on the growth rate at heading. These two values were negatively correlated. 3) “Early-vigor” types tended to produce more panicles but had a low rate of carbohydrate supply than “sustained-vigor” types. Either “potentiality” or “supply” was a limiting factor in grain production, depending upon the pattern of growth being either “early-vigor” or “sustained-vigor” type.