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Low dimensional fermionic quantum systems are exceptionally interesting because they reveal distinctive physical phenomena, including among others, topologically protected excitations, edge states, frustration, and fractionalization. Our aim was to confine 3He on a suspended carbon nanotube to form 2-dimensional Fermi-system. Here we report our measurements of the mechanical resonance of the nanotube with adsorbed sub-monolayer down to 10 mK. At intermediate coverages we have observed the famous 1/3 commensurate solid. However, at larger monolayer densities we have observed a quantum phase transition from 1/3 solid to an unknown, soft, and mobile solid phase. We interpret this mobile solid phase as a bosonic commensurate crystal consisting of helium dimers with topologically-induced zero-point vacancies which are delocalized at low temperatures. We thus demonstrate that 3He on a nanotube merges both fermionic and bosonic phenomena, with a quantum phase transition between fermionic solid 1/3 phase and the observed bosonic dimer solid. Probing fundamental quantum systems and their phase change is interesting. Here the authors demonstrate the existence of mobile quantum solid phase composed of dimerized 3He atoms and topology-induced vacancies using 3He adsorbed on carbon nanotube. [ABSTRACT FROM AUTHOR]

We describe some details of a new experimental setup for torsional oscillator (TO) measurement of $$^4$$ He monolayers adsorbed on a graphite surface. This setup is designed to seek for the possible supersolid phase, in which crystalline order coexists with superfluidity, in two dimensional (2D) solid $$^4$$ He below 300 mK. Among such 2D solids, the commensurate phase in the second layer on graphite is the most hopeful candidate for the novel supersolid phase since it is the lowest-density quantum solid ever found. An exfoliated graphite substrate we used is ZYX which has at least ten times longer surface coherence length compared to Grafoil, an exfoliated graphite most commonly used in previous experiments. The first version of TO we made has the resonant frequency of 786.8 Hz and the Q value of $$1.1\times 10^5$$ at $$T \le 10$$ mK. The resonant frequency of this particular TO without any He samples ( $$f_{\mathrm {cell}}$$ ) showed unexpectedly large temperature variation and non-reproducibility below 1 K as well as sudden jumps when mechanical shocks are applied to the experimental apparatus. We found the stability of $$f_{\mathrm {cell}}$$ is highly correlated with the temperature stability of 1 K pot in dilution refrigerator. [ABSTRACT FROM AUTHOR]

High power Large Orbit Gyrotron (LOG) [1] is now under development at FIR FU. First version of this device was recently manufactured and then assembled with power supply ETIGO-IV [2]. Results of preliminary tests of electron-optic system are presented. The conditions when stableflat form of current pulse realized are discussed. Analytical estimations of cathode-anode distance to achieve small influence of cathode plasma during high voltage (HV) pulse are performed. Two new electron gun versions with decreased influence of the cathode plasma on its impedance and pulse form are suggested and optimized. New optimal magnetic field distributions are found. First gun has quiasi-flat cathode configuration near the anode diaphragm and provides operating current about 60 A. Second one uses blade cathode with operating current about 30 A. Beam quality for both guns is suitable for LOG operation. [ABSTRACT FROM AUTHOR]

Epigenetic alterations like DNA methylation and the resulting inactivation of cancer-related genes often contribute to the development of various cancers. To identify the genes that are silenced by aberrant methylation in renal cell carcinoma (RCC), we subjected two RCC lines to methylated CpG island amplification/representational difference analysis. This identified 27 CpG islands. Combined bisulfite restriction analysis of these CpG islands in primary RCC cases revealed that four were methylated in a tumor-specific manner. One of these was identified as the human homeo-box gene B13 (HOXB13) gene, but the remaining three CpG islands were not associated with known genes. The methylation frequencies of HOXB13 in primary RCC samples and lines were 30 and 73%, respectively. The methylation status of HOXB13 correlated with the loss of its expression both in RCC lines and primary tumors, and methyltransferase inhibitor treatment induced the recovery of its expression. Exogenous expression of HOXB13 in RCC cells that lacked endogenous HOXB13 expression suppressed colony formation and induced apoptotic features. Furthermore, HOXB13 methylation correlated positively with tumor grade and microvessel invasion. These results suggest that HOXB13 is a novel candidate tumor suppressor gene in RCC and that its inactivation may play an important role in both RCC tumorigenesis and progression.Oncogene (2006) 25, 1733–1742. doi:10.1038/sj.onc.1209200; published online 7 November 2005 [ABSTRACT FROM AUTHOR]

Designs of cavities for fundamental and high harmonic operation in Large Orbit Gyrotron (LOG) are discussed. The fundamental operation allows one to use beam currents in the range from 200 A to 300 A achieve output power of the order of 9–10 MW at frequency 143.6 GHz. Mode competition calculations show that stable oscillations in the TE1,4 mode using high beam currents are possible even with the pitch factor 1.3 which is significantly lower than the design value 1.55. For the second harmonic operation, the maximum current used for excitation of the TE2,4 mode is 60 A and the optimum magnetic field is 7.6 T. A cavity design for fourth harmonic operation using the TE4,4 mode is also presented. [ABSTRACT FROM AUTHOR]

In the article, results of numerical simulation of the gun with the cusp of magnetic field are presented. Short pulse version of the gun with explosion emission is investigated. Some preliminary analytical estimation of the beam and gun parameters arc performed. Then, numerical optimization of the electrodes shape as well as magnetic field distribution is carried out. For preliminary separation of electrons and formation of the rectilinear beam, anode diaphragm is installed. After then, additional selection of electrons for decreasing the ripple is performed. For this purpose, channel walls are used for interception of some part of the electron beam. Reverse of the magnetic field in the diode part of the gun is formed. So, the formation of the rectilinear beam is combined with the region, where electrons obtain initial gyration energy. To prevent the disperse action of the own beam space charge forces, the system with big gradient of magnetic field (about 0.5-1 kGs/mm) is needed. According to results of the simulation, helical electron beam can be performed even at total compression ratio about 1000 and current density more than 50 kA/cm². The designed electron gun provides acceptable performance for the large orbit gyrotron, such as operating current close to 300 A, the pitch-factor value about 1.5-1.7, deviation of the guiding centers from the axis (the ripple) λ/10 and λ/6 for operation on 3-rd and 5-th cyclotron harmonic correspondingly (wavelength λ=0.5 and 0.3 mm) and velocity spread within the range 10-15%. [ABSTRACT FROM AUTHOR]

Transient expression of the β-glucuronidase (GUS) gene in suspension-cultured cells of tobacco was obtained after gene delivery with a pneumatic particle gun device driven by compressed air. Both the pneumatic pressure used to accelerate the particles as well as the distance between the point of release of the particles from the device and the location of the target cells could be varied. Efficiency of gene delivery was tested by accelerating pressure from 63 to 200 kg/cm and distances from 5 to 15 cm. At 150 kg/cm and 10cm, 618±49 blue spots of GUS-expressing cells were evenly distributed over the surface of the cell layer (3.5 cm diameter). The frequency of transient gene expression was estimated to be more than 1.2×10, which is comparable to, or even higher than, that obtained by the gunpowder-driven device. [ABSTRACT FROM AUTHOR]

Ten patients with carotid cavernous fistula (CCF) were reviewed. Single photon emission computed tomography (SPECT) for regional cerebral blood flow (rCBF) study was performed in six patients with fast flow shunt. Five of these six patients with fast flow shunt angiographically demonstrated cortical venous drainage, and two of these patients suffered intracerebral hemorrhage. The rCBF decreased in the region demonstrating the cortical venous drainage in five patients, and in one patient the angiography demonstrated arterial steal and the rCBF decreased in a part of the ipsilateral cerebral hemisphere. SPECT proved to be useful in assessing the cerebral circulation in cases of CCF. [ABSTRACT FROM AUTHOR]

Profiles of the genomic DNA of 104 strains of T. equigenitalis isolated from brood mares with contagious equine metritis in Hokkaido during the breeding seasons from 1980 to 1993, as well as those of five strains (SS28, EQ56, EQ59, EQ70 and HH139) previously isolated in Japan were examined after restriction digestion and crossed-field gel electrophoresis. These profiles were essentially identical to each other and the various isolates and strains appeared to have a common genotype, designated 'genotype J', with respect to two restriction enzymes, ApaI and NotI. These results suggest a common source for all these isolates obtained over the course of more than 10 years in Japan. [ABSTRACT FROM AUTHOR]

Matrix (M) and nonstructural (NS) genes of thirteen equine H3N8 and H7N7 influenza viruses were sequenced and analyzed from an evolutionary point of view. The M and NS genes of H3N8 viruses isolated between 1989 and 1993 evolved into two minor branch clusters, including isolates from Europe and the American continent, respectively. It was noteworthy to reveal that the nucleotide sequences of the M and NS genes of an earlier American strain showed highest homology to those of recent European viruses. “Frozen evolution” was observed in the M and NS genes of A/eq/LaPlata/1/88. It was also evident that the NS gene of an H7N7 virus from 1977 was very similar to that of a 1979-H3N 8 virus, while the M gene was closest phylogenetically to that of the earliest H7N7 virus isolated in 1956. Furthermore, the M2 protein of A/eq/Newmarket/1/77 virus contained a carboxyl terminal deletion of three amino acids. The evolutionary rates of the M and NS genes of H3N8 equine influenza viruses were estimated to be 5.4 × 10−4 and 5.1 × 10−4 substitutions per site per year, respectively, which were slower than those of human viruses. [ABSTRACT FROM AUTHOR]

A polymerase chain reaction (PCR) based assay capable of detecting and differentiating seven strains of equine arteritis virus (EAV) from around the world was developed. The primers for the PCR were chosen from the ORF 6 gene encoding the unglycosylated membrane protein (M). Viral RNA from cell culture fluids infected with each of the seven EAV strains and RNA from the live vaccine, Arvac, was detected by PCR using four sets of primers. The sensitivity of detection was increased from 100 to 1000 times by performing nested PCR enabling the detection of RNA at a level of 0.5-5 PFU. Differentiation among the virus strains and the live vaccine was achieved by cutting the PCR-amplified products from three sets of primers with six restriction endonucleases. Using this procedure it was possible to distinguish among the seven EAV strains used. [ABSTRACT FROM AUTHOR]

The complete sequence of the major core protein (VP3) gene of African horsesickness virus serotype 4 (AHSV-4; vaccine strain) was determined by analysis of a complete cDNA clone representing segment 3. The RNA was 2 789 bp long and a comparison of its sequence with that of bluetongue virus serotype 10 (BTV-10) revealed 58% nucleotide similarity. Based on these data, the reverse transcriptase-polymerase chain reaction (RT-PCR) technique was applied to the specific detection of AHSV using a pair of primers designed for AHSV-4 VP3 gene. Approximately 230 bp of PCR products were amplified by RT-PCR from the total RNA extracts (mRNA and dsRNA) of Vero cells infected with eight serotypes of AHSV. No product was observed analogous to other orbiviruses. The supernatant of the infected cell culture fluid without any RNA purification was also suitable as a template for RT-PCR after being denatured at 94°C for 5 min. The sensitivity of this method was between 10 and 10 TCID when viral RNA from the supernatant of infected cell culture was subjected to RT-PCR. The whole procedure for detecting the virus RNA by RT-PCR could be carried out within 5h. The RT-PCR with AHSV VP3 gene as a target was found to be a simple, highly specific and sensitive assay for AHSV. [ABSTRACT FROM AUTHOR]

Electropherotypes (ET), serotypes, and subgroups of equine rotaviruses isolated from foals in Japan were determined. The ETs of 136 isolates from 1981 through to 1991 were divided into six groups: ET-A-ET-F. The ET-A,-B, -C, -D, -E, and -F were present in 3, 1, 121, 9, 1, and 1 strains, respectively. Representative viruses of ET-A, -B, -C, and -D were identified as serotype G 3. Viruses of ET-E and -F were identified as serotypes G 10 and G 5, respectively. The four representative viruses of serotype G 3 did not belong to either subgroup I or II. The two viruses of serotypes G 5 and G 10 belonged to subgroup I. Serotype G 3 strains possessing ET-C were prevalent among the foals throughout the study period. [ABSTRACT FROM AUTHOR]

Six of 6 equine herpesvirus type 3 (EHV3) isolates, 5 of which were epidemiologically unrelated, produced a mixture of small and large plaque variants in equine foetal kidney cells under methylcellulose. In 4 of 4 instances the cleavage site(s) generating the Bam HI A fragment of large plaque variants was distinct from the site(s) for the same fragment of small plaque variants. [ABSTRACT FROM AUTHOR]

Proteins of Babesia equi piroplasms were characterized. The piroplasms of B. equi were purified by lysis of infected horse erythrocytes with N gas cavitation followed by separation in Percoll density-gradient centrifugation. The relative molecular weights (Mr) of major proteins separated by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis were 18, 28, 30, 41, 43, 54, 66.5, and 96 kDa. Immunoblot analysis using serum from an experimentally infected horse revealed six immunodominant proteins of 15, 18, 28, 30, 41, and 96 kDa. Two immunodominant proteins of 18 and 28 kDa were membrane-bound proteins as revealed by Triton X-114 phase partitioning. [ABSTRACT FROM AUTHOR]

From the magmatic emanations differentiation point of view it is possible to calculate some ratios such as F/CO, Cl/CO, SO/CO, SO/HS, HS/CO and CO/N in the tumarolic gases for the forecasting of volcanic activity. In order to predict the cruptions of a volcano it is needed to select several fumaroles or hot springs having different regimes of variation of the above ratios. The study of some fumaroles composition at the Asama. Mihara, Kirishima and other volcanoes in Japan showed a close connection between volcanic gas compositions and state of the volcanoes. [ABSTRACT FROM AUTHOR]

1. The radioactivity of a large number of volcanic gases from the craters, the fumaroles and hot springs in Japan is measured, and is never negligibly small, but often so large as comparable to that of the gases from the strongly radioactive mineral springs. 2. The existence of many radioactive elements such as Rn, RaA, RaB, RaC, Tn, ThA and ThB is confirmed in the volcanic gases, but An, isotope of Rn and Tn, is not yet found. 3. The variations of the radioactivity and the ratio (Tn/Rn) of volcanic gases are measured and the possibility for the detection of the variations of the volcanic activities is suggested. 4. The excessive distribution of Rn and Tn in the gas phase of fumaroles is a common phenomenon in the most fumaroles accompanied by hot waters in Japan. In many cases, these fumarolic gases are considered as the principal source of the radioactive substances in the hot spring waters situated closely to the fumaroles. 5. The mechanism of the introduction of the radioactive substances into the volcanic gases of fumaroles is discussed. The cost of this investigation was defrayed from a grant given by the Scientific Research Encouragement Grant from the Department of Education, to which the authors wish to express their thanks. [ABSTRACT FROM AUTHOR]

A 9-year-old boy with a rare combination of multiple coronary artery fistulas and congenital shunt between the portal and hepatic veins (portal-systemic shunt) is presented. The most likely pathogenesis for the portal-systemic shunt in this case was persistence of the ductus venosus as a bypass tract of the portal vein. This shunt is considered as one cause of cardiomegaly and dilatation of the hepatic vein in this case, and careful follow-up is mandatory because this shunt could induce portal-systemic encephalopathy. There are a few reports of an anomalous portal venous connection to the hepatic vein as a result of abnormal portal embryogenesis. We experienced a unique case of congenital portal-systemic shunt associated with coronary artery fistulas. The present paper reports angiographic findings in this case and the etiological importance of the congenital portal-systemic shunt. [ABSTRACT FROM AUTHOR]

Chemical properties of magmatic emanation can be estimated roughly by i) volatiles from rocks by heating at various temperatures, ii) volcanic emanations, iii) residual magmatic emanations, iv) calculation from chemical equilibrium between volatile matters and magmas. Magmatic emanation is assumed to consist all of the volatile matters in magmas such as H O, HCl, HF, SO H S, H, CO 2, N and others (halides, etc.) at about 1200°C, although various kinds of magmatic emanations can be formed at different conditions. Magmatic emanation separated from magmas will change their chemical properties by many factors such as changes of temperature and pressure (displacement of chemical equilibrium), and reactions with other substances and it will differentiate into volcanic gases, volcanic waters, volcanic sublimates, and hydrothermal deposits (hot spring deposits). At temperatures above the critical point of water, separation of solid phase (sublimates), liquid phase, and displacement of chemical equilibrium may take place, and gaseous phase will gradually change their chemical properties as will be seen at many fumaroles. Chloride, hydrogen, and SO contents will gradually decrease along with lowering temperature. Once aqueous liquid phase appears below the critical point of water, all the soluble materials may dissolve into this hydrothermal solution. Consequently, the gaseous phase at this stage must have usually a little hydrogen chloride as is observed at many fumaroles. Aqueous solutions must be of acidic nature by dissolution of acid forming components, and by hydrolysis (Chloride type). When a self-reduction-oxidation reaction of sulfurous acid takes place, an aqueous solution of sulfate type will be formed. At this stage, solid phases consist of the remained sublimates which are difficultly soluble in aqueous solution, and deposits formed by reaction in the hydrothermal solutions. The gaseous phases below the boiling point of water, have usually a little water, and consist mainly of CO type, H S type, N type, and mixed type owing to elimination or addition of components by reactions with waters or wall rocks according to their geological conditions. Aqueous solutions which was of acidic nature must be changed into alkaline solutions by reaction with wall rocks for a long time. When the oxidation of sulfur compounds takes place, an aqueous solution of sulfate type will be formed. Hydrogen sulfide type of water will be formed by reaction of sulfides with acid waters or absorption of hydrogen sulfide. Carbonate type of water will be formed when CO is absorbed. Solid phases at this stage consist usually of hydrothermal deposits except for that at solfatara or mofette. The course of differentiation of magmatic emanation could take place in more complicated ways than that of magmatic differentiation. [ABSTRACT FROM AUTHOR]

Reorientation of cucumber seedlings induces re-localization of CsPIN1 auxin efflux carriers in endodermal cells of the transition zone between hypocotyl and roots. This study examined whether the re-localization of CsPIN1 was due to the graviresponse. Immunohistochemical analysis indicated that, when cucumber seedlings were grown entirely under microgravity conditions in space, CsPIN1 in endodermal cells was mainly localized to the cell side parallel to the minor axis of the elliptic cross-section of the transition zone. However, when cucumber seeds were germinated in microgravity for 24 h and then exposed to 1 g centrifugation in a direction crosswise to the seedling axis for 2 h in space, CsPIN1 was re-localized to the bottom of endodermal cells of the transition zone. These results reveal that the localization of CsPIN1 in endodermal cells changes in response to gravity. Furthermore, our results suggest that the endodermal cell layer becomes a canal by which auxin is laterally transported from the upper to the lower flank in response to gravity. The graviresponse-regulated re-localization of CsPIN1 could be responsible for the decrease in auxin level, and thus for the suppression of peg formation, on the upper side of the transition zone in horizontally placed seedlings of cucumber., Competing Interests: The authors declare no conflict of interest.