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High-grade glioma is the most common brain tumor in adults, and the prognosis for patients diagnosed with this type of cancer is still poor. The biological behavior of the tumors is correlated to t ...

We observed an unconventional parity-violating vortex in single domain Sr 2 RuO 4 single crystals using a transport measurement. The current–voltage characteristics of submicron Sr 2 RuO 4 show that the induced voltage has anomalous components which are even functions of the bias current. The results may suggest that the vortex itself has a helical internal structure characterized by a Hopf invariant (a topological invariant). We also discuss that the hydrodynamics of such a helical vortex causes the parity violation to retain the topological invariant.

Antiferromagnetic ordering and spin frustration behaviors in the series of isostructural compounds, R 2 BaPdO5 ( R = rare earth), are reported. We have investigated the crystallographic, magnetic and thermal properties of the compounds, R 2 BaPdO5 ( R = Nd , Eu, Gd and Ho). R 2 BaPdO5 ( R = Nd , Gd and Ho) show paramagnetic properties at high temperatures originating only from the rare-earth ions and magnetic order at 2.1, 2.9 and 4.1 K, respectively. Ho2BaPdO5 shows a symmetrical peak of the heat capacity at T N and negligible residual entropy below the T N , suggesting a simple square lattice Ising model. On the contrary, Nd2BaPdO5 and Gd2BaPdO5 show Schottky type heat capacity at T N and large residual entropy far below the T N , suggesting spin frustration in them. The origin of the possible spin frustration in R 2 BaPdO5 ( R = Nd and Gd) is discussed in terms of relative strength of J and J ′ in the Shastry–Sutherland spin lattice.

The rockmover wrasse Novaculichthys taeniourus was observed using coral fragments for mound construction on the reefs of Kuchierabu-jima Island, Japan. The wrasse heaped between four and 71 pieces of coral fragments on each sand mound, and dived into the mound just before sunset. Coral fragments may facilitate the retention of sleeping sites under competition with other sand-diving wrasses.

Genetic parameters for dairy performance traits were estimated, breeding values for the traits of all breeding sires and cows were predicted and the genetic trends were estimated using the breeding values in the Central Cattle Breeding Station (CCBS). A total of 3,801 records for Bangladeshi Local, 756 records for Red Sindhi and 959 records for Sahiwal covering the period from 1961 to 1997 were used in this analysis. Traits considered were total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). The genetic parameters were estimated by the REML using MTDFREML program. The breeding values were predicted by a best linear unbiased prediction (BLUP). In all sets of data, the genetic trends for the dairy performance traits were computed as averages of breeding values for cows born in the particular year. The estimates of heritability for TLP (0.26 and 0.27) and DMY (0.28 and 0.27) were moderate in Bangladeshi local and Red Sindhi breed, respectively. Furthermore, the heritability estimate for LL (0.24) was moderate in Red Sindhi. The estimates of heritabilities for all traits were low in Sahiwal. The repeatability estimate was high for TLP, moderate for LL and moderate to high for DMY. All variances estimated in Bangladeshi Local were low, comparing the respective values estimated in both Red Sindhi and Sahiwal. On the other hand, additive genetic variances for the three traits were estimated very low in Sahiwal. The genetic trends for the three dairy production traits have not been positive except for the recent trend in Bangladeshi Local.

Reciprocal effects among local breeds and additive and heterosis effects were estimated for total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). Procedures for an optimum crossbreeding system were examined by comparing various crossbred combinations. Three data sets were chosen from the total records collected from 1962 to 1997. Data set I with a total of 5,938 records composed of 9 breed groups for reciprocal crosses, data set II with a total of 6,064 records composed of 5 breed groups for additive and heterosis effects and data set III with a total of 10,319 records composed of 42 breed groups for optimum crossbreeding system were analyzed. The least squares ANOVA was used. The reciprocal crosses between Red Sindhi and the Bangladeshi Local showed significant difference. When the Red Sindhi was used as cow, the cross was superior to the opposite in terms of the three performance traits. The results showed that additive breed effects on both TLP and DMY were positive and highly significant between Bos indicus and Bos taurus, whereas the individual heterosis effects were not significant. In general, any local breeds were improved two to three times by crossing with the Friesian once or twice. However, the effect was reduced when the grading up with the Friesian was repeated more than twice. On the other hand, when the local breed was crossed with the other breeds such as Holstein and Jersey, the improvement of TLP was less. Crossing the F1 cows with the Friesian bull gave further improvement. Almost the same trends were found also for LL and DMY. The local breeds and their crosses are raised mainly for draft animals, then it is recommended that the crossbreds between the local cows and Friesian are used for dairy purposes and more than 75% Friesian bloo di s used for beef. (Asian-Aust. J. Anim. Sci. 2002. Vol 15, No. 6 : 777-782)

We have synthesized single crystals doped with Cu atoms in TaSe3 which exhibits no Charge Density Wave (CDW) transition, and measured precisely the temperature dependence of the resistance. We discover an anomalous sharp dip in the temperature derivative of the resistance at about 91 K in Cu-doped TaSe3 , which is never observed in pure TaSe3 . The dip suggests that there is a phase transition with a relative increase in resistance. In addition, the dip is “γ ” shaped. We reveal that the same “γ ”-shaped dip in dR /dT is commonly observed at the CDW transition temperature in many CDW conductors, which is a universal consequence resulting from the opening and growth of a CDW gap on a Fermi surface. Furthermore, the result of the single-crystal X-ray diffraction (XRD) analysis implies that Cu-doping increases the lattice parameter of the a -axis and c -axis and decreases that of the b -axis, leading to an improvement in the nesting condition. Based on the “γ ”-shaped dip and the result of the single-crystal XRD analysis, we conclude that a CDW emerges by Cu-doping in TaSe3 .

In this work, the origin of the highly anisotropic superconducting transition in ZrTe3, where the resistance along the a axis, R a , is reduced at 4 K but those along the b axis, R b , and axis, R c', are reduced at 2 K, was explored with the application of a magnetic field and pressure by the electrical resistance measurements. We found that the behavior of the upper critical field and its anisotropy as well as the pressure dependence determined by the R a measurements are quite similar to those of R b . Moreover, the excess conductivity for R b indicates anomalous behavior. These results support an unconventional origin for the anisotropic transition rather than conventional superconducting fluctuation. The reduction in R a is due to filamentary superconductivity (SC) induced by locally bound electron pairs (local pairs), which correspond to bi-polarons, and the transition of R b corresponds to the emergence of bulk SC originating from the Cooper pairs triggered by the transfer of the local pairs.

The characteristics of sol-gel transition of a mixture made by mixing two kinds of gelling agents of different nature, i.e. gelatin and carrageenan were examined. The sample solutions consisted of 3.00 wt% gelatin solution, 1.00 wt% K-carrageenan solution and 4.00 wt% mixed solution which was prepared by mixing the said gelatin and carrageenan solutions in the ratio 3:1. In the experiment, the optical rotation and the dynamic viscoelasticity were measured under the same temperature change program. As the sample solutions were cooled, the carrageenan solution started to show a change in the specific rotation in the first place, followed by the mixed solution and finally the gelatin solution. The gelatin and the mixed solutions had the same increasing tendency in the specific rotation, whereas the carrageenan solution changed a little. When the mixed solution was chilled to set, it turned into a highly elastic gel. In the mixed solution, the gelation of carrageenan was found to precede that of gelatin.

Sulfur-oxidizing bacteria, Thiobacillus thiooxidans, werefound in a highly acidic (pH = 1∼1.5) crater lake, Yugama,seasonally flowing streams and soil in the catchment area of thecrater. Thiobacillus ferrooxidans was also found in some ofthe streams but not in the lake itself. The lake water containsaqueous carbon dioxide, hydrogen sulfide, polythionates andelemental sulfur in suspension which are the substrates for thegrowth of the sulfur-oxidizing bacteria as no organic compoundsexcept for the microorganisms themselves were detected. Thebacteria isolated from the Yugama water preferred polythionatesin the following order: S4O62> S5O62> S6O62On the other hand,H2S was more rapidly consumed by the bacteria thanpolythionates which were followed by elemental sulfur. In thecase of test-tube incubation, the optimum pH of the solution forgrowth of the bacteria was between 1.0 and 1.5, and forcultivation in growth medium plates between 2.5 and 3.5. Thebacteria hardly proliferated at pH 0.5 or below. In accordancewith these characteristics of the bacteria, numbers of thebacteria in the surface Yugama crater lake water were at minimum(< a few cells/mL) in February and at maximum (106 cell/mL)in August. The bacterial activity changed in accordance with thesurface lake water temperature, but not necessarily with thevariations in H2S and polythionates concentrations of the lakewater. Based on the variation in sulfur isotope ratios of sulfateand experimentally determined rate of oxidation of H2S in thelake water, the sulfate production rate by the bacteria in thecatchment area and the lake were estimated to 9.5 and 8.4g/m2/day, respectively, during the period from 1988 to 1990when the volcanic activity at Yugama was at minimum. Also stream,hydrothermal, H2S-oxidated SO24-inputs and outputs byseepage and precipitation have been calculated as 4.1, 32, 0.56,36, and 1.2 ton/day, respectively.

Recent progress in studies on low carrier concentration systems of magnetically ordered and non-magnetic heavy Fermion metals are discussed. Successive steps in the high field magnetisation, the magnetic structure, and the influence of high pressure are reported and the relation with the observed Fermi surface for CeP is discussed. The origin of the low carrier concentration in USb is also discussed based on the first observation of dHvA oscillations. It is also unambiguously demonstrated that the unconventional heavy Fermion state of Yb4As3 is intrinsic and not due to impurities.

We have shown that the superconducting transitions in ZrTe${}_{3}$ are successive from filamentary to bulk, based on experimental results obtained for a superconducting specific-heat anomaly and the anisotropic superconducting transition curve of resistivity. A small jumplike superconducting specific-heat anomaly with a large and widely extended tail was observed to closely follow the anisotropic zero-resistance transition. We concluded that the jumplike anomaly signifies the onset of the long-range order of Cooper pairs with the opening of a superconducting gap at ${T}_{C}$, while the large and widely extended tail indicates behavior induced by Cooper pairs with a very short coherence length. As a limit for a very short coherence length, we propose local pairs with Bose characteristics. As a result, we can understand that the filamentary superconductivity is caused by the local pairs, and the large and widely extended tail is in a crossover region between superconductivity induced by local pairs and that induced by Cooper pairs. Based on a discussion about the origin of the change in the pair coupling from the starting of local pairing to Cooper pairing in ZrTe${}_{3}$, we conclude that ``mixed bulk-filament superconductivity'' results from unique electronic structural changes in the quasi-1D+3D (D, dimensional) Fermi surfaces after the CDW transition.

The goal of breast reconstruction after breast cancer is to obtain symmetrical breasts, including the nipple-areola complex. However, in some cases the nipple-areola complex may not be symmetrical even though a symmetrical breast shape has been created. In such cases the nipple-areola complex has been transpositioned, leaving a scar to close the wound or skin graft in the original position. To treat this problem, skin surrounding the areola is removed and two pedicles are created to bear the nipple-areola complex. The nipple-areola complex is then moved to the proposed position and the surrounding circular edge of the skin is closed using a purse-string suture. The author performed this technique in three nipple-areolae of two patients. All the nipple-areolae were transposed to the proposed position to create symmetrical breasts without any complications. This technique can be used when the malpositioned nipple-areola complex is not too far from the proposed position. The nipple-areola complex can be moved without leaving any scar at the original position of the complex.

Summary Background The histopathological differentiation of malignant melanoma and Spitz naevus often presents diagnostic problems. Objectives We aimed to find out applicable diagnostic parameters other than routine pathology. Methods The cases included conventional melanomas and Spitz naevi as well as atypical spitzoid lesions that had posed diagnostic difficulties. We examined hotspots of mutation in the BRAF, NRAS and HRAS genes by polymerase chain reaction-based direct sequencing. We also analysed DNA copy number aberrations and the methylation of CpG sequences in several cancer-related genes by utilizing a novel methylation-specific multiplex ligation-dependent probe amplification method. Results Twenty three of 24 conventional melanomas showed at least one of the genetic and epigenetic alterations examined, although one acral melanoma did not show any alteration. By sharp contrast, 12 Spitz naevi with an unambiguous histopathology showed no or few chromosomal aberrations, no oncogene mutations and no methylation of CpG sequences. Of the 16 ambiguous spitzoid lesions, most of which were designated atypical Spitz tumour by one of the authors, all but one showed no mutations, no methylations and few copy number aberrations. However, three tumours showed copy number loss of the cyclin-dependent kinase inhibitor 2A gene (CDKN2A), an alteration observed frequently in melanomas but not found in conventional Spitz naevi. These results show that, although most atypical Spitz tumours do not differ from conventional Spitz naevi showing virtually no genetic and epigenetic aberrations, some cases may have chromosomal aberrations that include copy number loss of the CDKN2A gene. Conclusions Genetic and epigenetic analyses may be useful as an additional diagnostic tool to distinguish between melanoma and Spitz naevus, and may help to define subgroups in atypical Spitz tumours.

The fuzziness index is described as one of the most efficient and useful experimental tools to examine human decision-making in the area of statistical judgement. This study investigated how statistical significance levels were treated and interpreted by various researchers by using the fuzziness index to measure the degree of fuzziness in hypothesis-testing. The fuzziness index showed a significant association between the magnitude of the fuzziness and the critical point of the human statistical decisions. The research demonstrated the possibility of measuring the human imprecision of the decision boundary, and the effectiveness of the fuzziness index in assessing underlying psychological mechanisms in decision-making. >

The implementation of the fuzziness index in measuring response style in psychosocial questions was examined, The fuzziness index revealed significant individual differences in response styles in psychological questionnaires, Significant correlations between the fuzziness in psychosocial behaviors and intellectual abilities were presented. The study highlighted the future possibility in modeling the degree and location of fuzziness in order to better understand enormously diverse human characteristics and psychological systems. >

A "corporate technology stock" model based on the concept of "depreciation" facilitates understanding of the corporate technological process and derives a numerical model and a formula for deciding R&D expenditure and high performance investment patterns. Numerical simulations revealed that the model accords satisfactorily with experience In industry, and provides a new methodology for the corporate management of technology.

The purpose of the present study was to explore applications of fuzzy set theory to the measurement of consumer purchasing attitudes and consumer decision-making style preferences in three groups of older adults. The question of interest was: what information can the analysis of fuzziness index provide that an analysis of traditional Likert-type scale raw score does not provide? The original study and results of the raw score analysis are described. The raw score results are compared with analyses of fuzziness index derived from raw scores. Finally, a comparison of analyses of mean fuzziness index with analyses of the standard deviation of fuzziness index is made. >

We report the results of the specific heat measurements at low-temperatures of the binary alloy Ti0.5V0.5 single crystal which undergoes the superconducting transition at 7.20 K. The single crystal of Ti0.5V0.5 is not only one of the strong-coupling superconductors but also a dirty type-II superconductor above about 2 K. However, this material exhibits anomalous behaviors in the specific heat below about 2 K. We attribute this anomalous behavior to the transition from the superconducting state into a superconducting glass state around about 2 K.

We have found parity-violating current-voltage (I–V) curves in a single domain of Sr 2 RuO 4 superconductors. The induced voltage V is an even function of bias current I below superconducting transition temperature. The anomalous I–V curves show that positive voltage is detected regardless of the current direction. The result implies the parity violation of I–V curves.

In order to determine the properties of the intestinal serotonin (5-HT) transport system, we studied 5-HT uptake by villous cell preparations isolated from the rat jejunum. These enterocytes, probably heterogenous in cell population, accumulated 5-HT against concentration gradient up to a concentration 28 times that in the medium; this accumulation occurred in a temperature-dependent fashion. Most of the uptake was the result of a saturable process at low substrate concentrations. The saturable uptake was inhibited by 1 mM potassium cyanide or 1 mM ouabain or by substitution of other cations and sugars for Na+ in the medium. On the other hand, neither several amino acids nor putrescine had any effect on 5-HT uptake. Kinetic analysis yielded a Km value of 3.63 x 10(-7) M and a Vmax value of 5.76 pmol.10(6) cells-1.min-1 for this uptake process. Imipramine inhibited 5-HT uptake in a concentration-dependent fashion, with a Ki value of 3.66 x 10(-7) M. 5-HT uptake was also inhibited by ethyleneglycol-0,0'-bis(2-aminoethyl)-N,N,N',N'-tetraacetic acid, by verapamil, by N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide and by phorbol 12-myristate 13-acetate. These findings suggest that the present enterocyte preparation had a relatively specific secondary active transport system for 5-HT.

Ultraviolet radiation in sunlight damages DNA in plants, but little is understood about the types, lesion capacity, and coordination of repair pathways. We challenged intact alfalfa seedlings with UV doses that induced different initial levels of cyclobutyl pyrimidine dimers and measured repair by excision and photoreactivation. By using alkaline gel electrophoresis of nonradioactive DNAs treated with a cyclobutyl pyrimidine dimer-specific UV endonuclease, we quantitated ethidium-stained DNA by electronic imaging and calculated lesion frequencies from the number average molecular lengths. At low initial dimer frequencies (less than ~30 dimers per million bases), the seedlings used only photoreactivation to repair dimers; excision repair was not significant. At higher damage levels, both excision and photorepair contributed significantly. This strategy would allow plants with low damage levels to use error-free repair requiring only an external light energy source, whereas seedlings subjected to higher damage frequencies could call on additional repair processes requiring cellular energy. Characterization of repair in plants thus requires an investigation of a range of conditions, including the level of initial damage.

The chromosomal structure of the extremely halophilic archaebacterium Halobacterium salinarium was examined. Sheared chromosomes prepared from the bacteria in the late exponential phase were separated into two peaks (peaks I and II) by sucrose gradient centrifugation, suggesting that the chromosomes consist of two parts differing in quality. The UV spectra of peaks I and II resembled those of DNA and eukaryotic chromatin, respectively. Electron microscopic observations revealed that the major component of peak I was protein-free DNA, while the major components of peak II were rugged thick fibers with a diameter of 17 to 20 nm. The rugged fibers basically consisted of bacterial nucleosome-like structures composed of DNA and protein, as demonstrated in experiments with proteinase and nuclease digestion. Whole-mount electron microscopic observations of the chromosomes directly spread onto a water surface revealed a configuration in which the above-described regions were localized on a continuous DNA fiber. From these results it is concluded that the H. salinarium chromosome is composed of regions of protein-free DNA and DNA associated with nucleosome-like structures. Peaks I and II were predominant in the early exponential phase and stationary phase, respectively; therefore, the transition of the chromosome structure between non-protein-associated and protein-associated forms seems to be related to the bacterial growth phase.

We observed quantum fluctuations of the superconducting phase θ in single domain Sr2RuO4 single crystals using a transport measurement. The temperature dependence of the resistivity of submicron Sr2RuO4 shows that a finite resistivity below the superconducting transition temperature of Tc = 1.69 K. The results may suggest that the finite resistivity is occurred by the flow of vortices due to quantum fluctuations of the superconducting phase θ in the same way as one-dimensional Josephson junction array systems.

We report the measurement of the low-temperature specific heat of Ti0.5V0.5 single crystal whose superconducting transition temperature Tc is 7.20 K. The value of the specific heat jump at Tc is large, namely, γTc=2.22. This result shows that Ti0.5V0.5 is one of the strong-coupling superconductors.

We report the results of the electrical resistivity and the low-temperature specific heat measurements of CoSi2 single crystals in the normal metallic state and superconducting regime. The results show that CoSi2 is truly a noble-metal compound as suggested by photoemission experiments and band-structure calculations. A significant point is that the superconductivity of this noble-metal compound can be described by the BCS theory.