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The kaonic deuterium measurement at J-PARC and DAΦNE will provide a piece of information still missing to the antikaon-nucleon interaction close to threshold, providing valuable information to answer one of the most fundamental problems in hadron physics today - to the yet unsolved puzzle of how the hadron mass is generated. For this a new X-ray detector system has been developed to measure the shift and width of the 2p → 1s transition of kaonic deuterium with a precision of 60 eV and 140 eV, respectively.

Recently, the shift of the kaonic helium-4 2p state was precisely determined by the E570 and SIDDHARTA experiments. Prior to the experiment by E570, the average of three earlier experimental results showed - 43±8 eV, while most of the theoretical calculations give ∼ 0 eV. This five-sigma discrepancy between theory and experiment was known as the "kaonic helium puzzle". A recent theoretical model showed a possible resonance-like shift of maximum 10 eV for a certain value of a deep antikaon-nucleon interaction potential, which is different in helium 3 and helium 4. The E570 experiment determined the shift of the kaonic helium-4 2p state as +2±2 (stat)±2 (sys) eV in 2007. The SIDDHARTA experiment determined the shift as 0±6 (stat)±2 (sys) eV in 2009. The results of these experiments resolved the long-standing puzzle. A new experiment of the kaonic helium-3 X-ray measurement is being prepared by the J-PARC E17 collaborators, and the kaonic helium-3 X-ray data taken very recently by the SIDDHARTA experiment are on the way to be analyzed. The results of the E570, E17 and SIDDHARTA experiments examine the strong interaction for light nuclei with different isospin, and test furthermore recent theoretical predictions. © 2010 American Institute of Physics.

The transcription factor DeltaFosB (Delta FosB) accumulates in a region-specific manner in the brain during chronic exposure to stress, drugs of abuse or other chronic stimuli. Once induced, DeltaFosB persists in the brain for at least several weeks following cessation of the chronic stimulus. The biochemical basis of the persistent expression of DeltaFosB has remained unknown. Here, we show that the FosB C-terminus, absent in DeltaFosB as a result of alternative splicing, contains two degron domains. Pulse-chase experiments of C-terminal truncation mutants of full-length FosB indicate that removal of its most C-terminal degron increases its half-life approximately fourfold, and prevents its proteasome-mediated degradation and ubiquitylation, properties similar to DeltaFosB. In addition, removal of a second degron domain, which generates DeltaFosB, further stabilizes FosB approximately twofold, but in a proteasome-independent manner. These data indicate that alternative splicing specifically removes two destabilizing elements from FosB in order to generate a longer-lived transcription factor, DeltaFosB, in response to chronic perturbations to the brain.

We investigated the effect of Li doping into Er-doped GaAs and Er, O-codoped GaAs on the enhancement of photoluminescence (PL) intensity. The Li doping into Er-doped GaAs increases the integrated intensity by 50 times higher than that from the Er-doped layer without Li doping. Main peak position of the Er, Li-codoped layer was slightly smaller than that of the Er-doped layer. This difference of peak position means that Li doping induced Er-related active centers different from those in Er-doped layer are formed. In the previous study, we have revealed that oxygen doping into Er-doped GaAs produced sharp and strong PL peak intensity due to Er-2O center. The Li doping into Er, O-codoped GaAs increases the integrated intensity twice higher than that from the Er, O-codoped layer without Li doping. However, the peak intensity decreased and the PL spectrum shape becomes broader. These results indicated that Li doping partly modified the Er-2O center and introduced many kinds of luminescent Er centers.

Direct growth of high-quality, thick CdTe (211) epilayers, with thickness up to 100 µm, on Si (211) substrates in a vertical metalorganic vapor phase epitaxy system is reported. In order to obtain homo-orientation growth on Si substrates, pretreatment of the substrates was carried out in a separate chamber by annealing them together with pieces of GaAs at 800–900°C in a hydrogen environment. Grown epilayers had very good substrate adhesion. The full-width at half-maximum (FWHM) value of the x-ray double-crystal rocking curve from the CdTe (422) reflection decreased rapidly with increasing layer thickness and remained between 140–200 arcsec for layers >18 µm. Photoluminescence measurement at 4.2 K showed high-intensity, bound excitonic emission and very small defect-related deep emissions, indicating the high crystalline quality of the grown layers. Furthermore, a CdTe/n+-Si heterojunction diode was fabricated that exhibited clear rectifying behavior.

High-quality epitaxial CdTe layers were grown on Si(2 1 1) substrates in a metalorganic vapor-phase epitaxy. In order to obtain homo-orientation growth on Si substrates, pre-treatment of the substrates was carried out in a separate chamber by annealing them together with pieces of GaAs at 800–900 °C in a hydrogen environment. Grown epilayers had very good substrate adhesion. The full-width at half-maximum value of the X-ray double crystal rocking curve from the CdTe(4 2 2) plane decreased rapidly with increasing layer thickness, and remained between 140–200 arcsec for layers thicker than 18 μm. Photoluminescence measurement at 4.2 K showed high-intensity bound excitonic emission and very small defect-related deep emissions indicating the high crystalline quality of the grown layers.

We have reported that infusion of prostaglandin synthesis inhibitor (PGSI) reduced the severity of hypotension during normothermic cardiopulmonary bypass (CPB). In the present study, we investigated the effects of PGSI on humoral conditions and whole body oxygen metabolism during normothermic CPB conducted for 60 min in 8 adult goats. The PGSI group (n = 4) was administered 100 to 150 mg of flurbiprofen, a potent PGSI, before and during CPB, and the control group (n = 4) was administered noradrenaline (NA) to restore hypotension. The prostaglandin E2 (PGE2) and NA concentrations in the PGSI group were significantly lower than those of the control group (PGE2 8.8 +/- 1.0 versus 30.3 +/- 11.5 pg/ml, NA 431 +/- 197 versus 3847 +/- 2,153 pg/ml). The adrenaline concentration was not significantly different between the groups. The oxygen consumption and the oxygen extraction rate were not significantly different between the groups, but the blood lactate level in the PGSI group was lower than that of the control group (34.3 +/- 7.6 versus 43.7 +/- 3.8 mg/dl). In conclusion, PGSI improves humoral disorder and thus prevents inadequate tissue oxygen delivery.

Using low-energy electron diffraction, Auger electron spectroscopy and STM, the peculiarities of the Al/Si(1 0 0) interface formation at 400–550 °C has been studied. At low Al coverages (∼0.05–0.2 ML), interaction of Al atoms with a top Si(1 0 0) substrate layer proceeds by two competitive mechanisms. First mechanism prevails at Si(1 0 0) surface with a low density of missing-dimer defects and resides in the formation of the specific Al–Si clusters. The second mechanism is stimulated by the presence of missing-dimer defects and resides in substitutional incorporation of Al atoms in the top Si(1 0 0) substrate layer. Both mechanisms result in the liberation of the surface Si atoms which agglomerate into flat islands. The Si mass transport and Al incorporation have been treated quantitatively, the composition of the Al–Si clusters has been estimated and the cluster structural model has been constructed.

The safety data of the 76 liquid crystal components with CN-group, which were officially excluded from the list of ‘deleterious substances’ are discussed. The acute toxicity of the 496 liquid crystal components without CN-group being used in the market and classified according the terminal groups and the linkages are shown. The statement on the safety of the liquid crystal materials by the three liquid crystal material suppliers is made.

The coexistence of two deep donors in Al2Ga1−xAs:Se with and without a capture barrier is reported. The difference of their nature is found in the dependence of the electron emission process on filling pulse time, temperature, and pressure.

The inelastic scattering processes of atoms associated with the excitation of the translational vibration mode on molecules adsorbed on solid surfaces, which have been reported in recent experiments have been investigated by numerical calculations using a simple model. In this model, in order to estimate the inelastic effects it is considered that the molecule position can move parallel to the surface one-dimensionally when the molecule is in collision with a moving atom. The numerical results show that there is a branching of the inelastic scattering waves and its behaviour depends strongly on the angle of the atom incidence as measured from the surface.

Silicon-doped GaAs layers have been grown on patterned GaAs(111)A substrates with equilateral triangles by molecular beam epitaxy. Lateral carrier confinement structures are confirmed by cathodoluminescence (CL) spectra: a (111)A surface is p -type and (311)A sidewalls are n -type. The confined (111)A region is reduced to submicron scale by reducing the size of the photoresist pattern. Furthermore, strong emission from the confined region and lateral modulation of peak wavelength are observed in the CL spectra of Al 0.3 Ga 0.7 As GaAs single quantum well grown on the patterned (111)A substrate. This modulation is caused by a decrease in GaAs layer thickness due to Ga migration from the (111)A surface to the (311)A surface. These results indicate that MBE growth on the patterned (111)A substrate is effective for fabricating submicron carrier confinement or optical confinement structures.

Diffusion of Si-acceptors (Si occupying As sites) in δ-doped GaAs grown on GaAs(111)A has been investigated by secondary ion mass spectrometry (SIMS). We have measured the diffusion parameters in GaAs(111)A and found that they differ from those in GaAs(001). The diffusion coefficient in GaAs(111)A is smaller than that in GaAs(001) and the activation energy in GaAs(111)A is larger than that in GaAs(001). Furthermore, the diffusion mechanism of Si in GaAs(111)A has been investigated by photoluminescence; we have found that in p-type layers Si-donors (Si occupying Ga sites) diffuse easily to As sites. The activation energy of Si-acceptor diffusion is 2.74 ± 0.11 eV . These results indicate that Si-acceptors are more stable than Si-donors.

The aim of our study is to develop NOx sensors that can measure NOx concentrations in exhaust gas. The present study investigates the gas-sensing properties of YBa 2 Cu 3 O 7 − δ thin films, deposited on a SrTiO 3 substrate by the ion-beam sputtering method. The thin film we made exhibits high sensitivity to NO at 350 °C, and the NO sensitivity increases with NO concentration in the range 30–3000 ppm NO. At 350 °C, the YBa 2 Cu 3 O 7 − δ thin film shows hardly any sensitivity to CO, H 2 and CH 4 gases that are also present in exhaust gas, giving it excellent selectivity. It is generally considered that the resistance of YBa 2 Cu 3 O 7 − δ irreversibly increases due to the absorption of NO, but this irreversible increase of the YBa 2 Cu 3 O 7 − δ resistance is not observed in the thin films we made.

The effects of off-angle of misoriented GaAs(111)A substrates on the thermal stability of Si atoms in Si atomic layer doped GaAs layers have been investigated by SIMS. This off-angle is found to strongly affect diffusivity; the diffusion coefficient for exactly (111)A is the smallest, and becomes large as the off-angle increases in the [110] or [001] direction. Such a diffusivity dependence can be understood by the density of the step, which is caused by substrate misorientation. Furthermore, the diffusivity of Si depends on the occupation site of Si; Si atoms in p-type layers where the Si occupies As sites are more stable than Si atoms in n-type layers where the Si occupies Ga sites. These results show that Si δ-doped layers on (111)A are suitable as p-type doped thin layers with their low diffusivity in electronic devices.

A method of estimating the inter-grain strength of sintered ceramics is proposed by means of a simplified analytical crack-propagation model. The analysis is focused on the determination of inter- or trans-granular fracture path. The criterion of crack-path selection is based on the total released energy rate of the system on the crack extension. The hexagonal column is chosen as the grain shape featuring a silicon nitride crystal structure. The crack-propagation paths are shown, and the ratio of surface-formation-energies on inter- and on trans-granular paths is related with the inter-/trans-granular area ratio on the fracture surface, so as to estimate the strength of sintered ceramics.

We have measured, for the first time, the light-intensity dependence in photocatalytic decomposition of water over K4Nb6O17 In higher light-intensity region, the rate of reaction is proportional to the square root of the light intensity. In lower light-intensity region, on the contrary, the rate is almost linearly proportional to the light intensity. We propose a reaction model whose main path of the reaction loss is the recombination of the charges generated under b and -gap radiation. This model describes the light-intensity dependence of this reaction well.

In the mechanism of damage to red blood cells (RBCs) caused by a centrifugal pump, the prolonged effects to the RBC membrane caused by exposure to shear stress remain unclear. We focused on the band 3 protein (B3), one of the major proteins in the membrane skeleton, and investigated the ultrastructural alterations of the RBC membrane with loaded shear stress. Using flow cytometry, the relative amount of B3 was examined in relation to RBC deformability. The results, with continuous exposure to low shear stress, showed cell downsizing, an increase in B3 density, and a decrease in the deformability of the RBC membrane. Exposure to high shear stress does not appear to exert any influence on the membrane skeleton of the RBC. Therefore, in addition to conventional processes including the instantaneous destruction of a cell due to intense shear stresses, the results of the present study indicate the presence of another process based on changes in membrane proteins leading to cell fragmentation. Under low shear stress, the RBC membrane skeleton shows delayed destruction, which is exhibited as a disorder of B3 distribution, and the related membrane dysfunction includes decreases in RBC deformability and stability.

The oxidation states of manganese in the La1−xMnO3−δ (x = 0.09–0.11) were investigated by electron spin resonance (ESR) and iodometry. The ESR analysis carried out at room temperature for the samples prepared in air revealed the presence of broad peaks at g = 2.0, considered to be relevant to Mn2+. It was also found that the intensity of the peak increased as lanthanum vacancy content increased. The average valence state of manganese, determined by iodometry, was approximately 3.2, and decreased by 1 as the lanthanum vacancy increased by 1. Similar trends were observed with the samples prepared at Po2 = 1×10−7. The results indicated that Mn2+ is stably present in the La1−xMnO3−δ having an average valence number exceeding 3.0. A series of experimental results with respect to the non-stoichiometry of La1−xMnO3−δ can be explained by assuming that Mn2+ is stabilized after forming a complex with a lanthanum vacancy and two oxygen vacancies.

Several new classes of low polar, low viscous and optically weak anisotropic two- and three-ring fluorinated liquid crystals (LCs) with ether terminal groups are presented. Their material properties are investigated and compared with those of fluorinated LCs with alkenyl terminal groups. The 4-fluoro-phenylbicyclohexane ethers were found to exhibit dielectric anisotropies Δewhich are similar to those of the corresponding alkenyls with 1-propenyl and 3-pentenyl group, whereas the alkenyls with 4-pentenyl group exhibit considerably lower Δe-values. The optical and dielectric anisotropies of difluoro-ethers with odd numbers n of the methylene groups separating the ether oxygen from the rigid cores of the molecules are comparable, whereas compounds with odd n′s were found to exhibit lower vis-coelastic ratios γ/K and therefore shorter response times in twisted nematic liquid crystal displays (TN-LCDs) than their even counterparts. In mixtures designed for thin film transistor (TFT)-addressed TN-LCDs ...

The highest efficiencies reported of SrS:Ce3+ and CaS:Eu2+ electroluminescence have been observed on RF-sputtered samples, showing completely ZnS-like electro-optical behaviour with loss-free acceleration of electrons evidenced in avalanching characteristics.

Above room temperature operation of InAs/AlSb quantum cascade lasers emitting at around 6 mum are reported. The emission originates from the vertical transition in double quantum wells. The threshold current in pulsed mode is 5.3 kA/cm2 at 300 K and maximum operating temperature is 373 K.

In 2003, NA60 collected data on dimuon production in indium-indium collisions at 158 GeV per incident nucleon, to study several anomalies previously observed in high-energy heavy-ion collisions at the CERN SPS. Among these anomalies stands the observation, by NA50, that the production yield of J/y mesons is suppressed in central Pb-Pb collisions beyond the normal nuclear absorption defined by proton-nucleus data. This behaviour was predicted to occur if the matter produced in these extreme collisions goes through a phase of deconfined partonic matter, where the charmonium states would be dissolved either due to the screening of their binding potential when the medium temperature exceeds certain critical thresholds (thermal transition, QGP) or when the density of interacting partons exceeds certain thresholds (geometrical transition, percolation). Thanks to its exceptionally good vertexing capabilities, NA60 is able to accurately study the centrality dependence of J/y production without using the Drell-Yan sample as reference. Our data shows that the J/y is anomalously suppressed for In-In collisions with more than ~ 90 participants nucleons. The comparison with three theoretical predictions shows that none of them properly describes the observed suppression pattern.

We report on a new self-alignment (SA) process and microwave performance of ALE/MOCVD grown InP/InGaAs heterojunction bipolar transistors (HBT's) with a base doping concentration of 1/spl times/10/sup 2/0 cm/sup -3/. We obtained f/sub T/ of 161 GHz and f/sub max/ of 167 GHz with a 2/spl times/10 /spl mu/m emitter. These high values indicate the best performance of InP/InGaAs HBT's ever reported, in so far as we know. These values were attained by reducing the base resistance using ALE/MOCVD and base-collector capacitance using a new SA process. These results indicate the great potential of these devices for ultrahigh-speed application. >

This paper presents the simulated and measured performance of 50 kHz to 40 GHz distributed amplifier MMICs. The chips were fabricated in a double-doped AlGaAs/InGaAs/AlGaAs p-HEMT technology and designed using a microstrip configuration.. The driver MMIC achieves 40-GHz bandwidth and provides 6.6 V/sub p-p/ which is ideal for lithium niobate optical modulator driver applications.

The authors discuss the modeling and operating characteristics of InGaAs/In(AlGa)As resonant-tunneling hot electron transistors (RHETs), using a self-consistent calculation for a resonant-tunneling emitter and a Monte Carlo simulation for hot electron transport in the base region. Coupled plasmon-longitudinal-optical-phonon-mode scattering and electron-electron (e-e) scattering in the Landau damped regime are taken into account. It is found that the RHET has an operating region where the collector transfer ratio is equal to or greater than 1 due to e-e scattering. >

A green-color AC electroluminescent device with ZnS:TbOF thin films has been fabricated by diode RF-sputtering. The effect of oxygen doping and sputtering conditions on the device performance has been investigated. It has been found that the performance improvement can be achieved by codoping oxygen into the active layers. >

AlGaAs/GaAs HBTs having an f/sub max/ of 120.9 GHz and a breakdown voltage over 10 V of BV/sub ceo/ suitable for a high-speed and large voltage swing driver circuit have been demonstrated. Using these HBTs, an optical external modulator driver circuit with 29 ps of t/sub /spl tau// and 25 ps of t/sub f/ which make it possible to operate at 10 Gb/s was realized. >

Research activities to improve the DC and RF performance of RHETs are reviewed. A description is given of RHET integrated circuits, including two-input and three-input logic gates. Using these logic gates and new collector barrier structures, a RHET latch circuit and a full adder have successfully been demonstrated at 77 K and require only one half to one quarter of the number of transistors needed for a conventional full adder. >

We have developed a high-performance l0-Gbit/s optical receiver using an avalanche photodiode (APD) and heterojunction bipolar transistor (HBT) ICs. Using an InP-InGaAs APD, it is possible to fabricate a compact and cost-effective optical receiver without an optical preamplifier for applications such as short-haul trunklines and local area networks.

Aortic pressure declines during cardiopulmonary bypass (CPB), particularly at normothermia. It has been reported that administering vasoconstrictors during normothermic CPB (NCPB) to restore perfusion pressure might induce hypoperfusion of splanchnic organs. We have reported that prostaglandin (PG), metabolized in the lung but increased during CPB, might have played a substantial role in hypotension, and that a PG synthesis inhibitor (PGSI) could improve hypotension during CPB. This study was designed to examine whether regional perfusion of splanchnic organs was reduced when PGSI restored systemic perfusion pressure during NCPB. NCPB was performed in eight adult goats for 60 minutes (body weight 57.0 +/- 5.9 kg). PGSI was administered in group P (n = 4), while norepinephrine was administered in group C (n = 4), to keep aortic pressure in the range of 50 to 80 mm Hg. The total systemic flow was maintained at approximately 70 ml/kg/min. Tissue blood flow was measured by means of the colored microsphere method before and 30 and 60 minutes after the start of CPB. In group P, gut blood flows after the start of CPB were higher than those before CPB, significantly in the stomach and jejunum at 30 minutes (p < 0.05), whereas gut blood flows in group C were decreased or not changed. In conclusion, PGSI prevents hypotension without impairing gut perfusion during NCPB.

A $\mathrm{Si}(100)c(8\ifmmode\times\else\texttimes\fi{}2)$ surface phase has been fabricated using atomic-hydrogen-induced self-organization followed by hydrogen extraction by the tip of scanning tunneling microscope. Similar to a conventional $\mathrm{Si}(100)2\ifmmode\times\else\texttimes\fi{}1$ surface, the new phase is built of Si dimer rows, but with every second dimer row being missing. The second-layer Si atoms in the troughs between dimer rows are also dimerized. The second-layer Si dimers at the opposite sides of a top Si dimer row demonstrate a tendency to be out of phase. This configuration induces buckling of the top Si dimer with a $c(8\ifmmode\times\else\texttimes\fi{}2)$ periodicity.

In this study, we focus on a quench detection method for a cryocooler-cooled double pancake coil wound with an YBCO bundle conductor for superconducting magnetic energy storage. Because the local normal-zone propagation velocity is significantly slower in a high-temperature superconducting coil than that in a low-temperature superconducting coil, it is difficult to detect the local normal transition using a voltage between both coil ends. In the application of an YBCO coil for superconducting magnetic energy storage, quench detection is considered to be more difficult because of the noise of the converter or other equipment. Therefore, the normal transition and quench must be detected using some other method. A current detection method, which measures the current redistribution in the YBCO coil with hall probes, was proposed and verified to be able to determine the normal transition by the numerical simulations in the previous paper. In this study, on the basis of the current detection method, the experiments and numerical simulation were performed on a cryocooler-cooled small model double-pancake coil wound with an YBCO bundle conductor composed of four electrically insulated YBCO tapes. As the results, the current detection method was verified to be effective in detecting the local normal transition; Hall probes were used to measure the magnetic field and to estimate the current in individual YBCO tapes making up the bundle conductor.

In recent years, the quality of high-temperature superconductors (HTS) has been improving. Our goal is to apply an HTS coil to superconducting magnetic energy storage, because an HTS coil is more thermally stable than a low-temperature superconductor coil owing to high thermal margin during its transition to the normal state and its high thermal capacity at a high operational temperature. On the other hand, to enhance the reliability and safety of an HTS coil, it is necessary to establish a stability criterion to prevent thermal and mechanical damages during a quench. Therefore, we have to clarify the thermal behavior of a cryocooler-cooled HTS coil assuming practical applications. In this study, we evaluated the cooling effect using a numerical simulation and thermal conduction experiments. The numerical simulation was based on the finite element analysis, and the thermal conduction experiments were carried out on a model coil wound with electrically insulated copper and stainless steel laminated tapes. These had the same shape and dimensions as YBCO tape, assuming an application to an superconducting magnetic energy storage coil. We focused especially on the cooling effect of a winding with paraffin impregnation compared with that of a dry winding.

α-Thienyl or α-pyrrolyl groups were bonded to α-positions of benzo[2,1-b:3,4-b']dithiophene-4,5-dione via Stille coupling reactions followed by intramolecular benzoin condensations, giving a novel terameric π-congugated oligomers. UV-vis and elctrochemical studies for these oligomers indicate that the heterocyclic substituents selectively destabilize the HOMO-level to result in small HOMO-LUMO gaps.

The zirconium silicide intermetallic compounds of 16H crystal structure are good materials for high temperature structural applications because of their high melting point and low density. Their shortcoming is low ductility. To increase ductility, new ternary zirconium silicide intermetallic compound of 16H crystal structure, Si3Y3Zr2, has been designed by substituting yttrium atoms into zirconium 6g point set sites.Near-neighbor diagrams are used to examine the bonds in Si3Y3Zr2, whose bonds are more symmetric than other 16H binary intermetallic compounds.Melting points of intermetallic compounds of 16H crystal structure depend upon the strain parameters of N4d-N4d(2-2) bonds. The melting point of Si3Y3Zr2 is estimated to be higher than that of Si3Zr5 (2500 K). It is predicted that Si3Y3Zr2 is a good material for high temperature structural applications.

The authors report on the findings regarding external magnetic field effects on the H 2 –O 2 reaction on a SnO 2 surface by the measurements of the electric conductivity of SnO 2 thin films. Further, we have succeeded in directly measuring external magnetic field effects on H 2 –O 2 reaction on an SnO 2 surface and found that the rate of increase in the reaction rate reached approximately 14% under the condition of 623 K and 5 T.

Introduction: Hedgehog (Hh) signaling pathway is crucial for growth and patterning during embryonic development. We have shown that Hh pathway is constitutively reactivated in human breast cancer (Kubo M et al. Cancer Res 2004). Recently, it has been proposed that only a small subset, termed cancer stem cells (CSCs), posseses tumorigenicity. And, several investigations suggest contributions of morphogenesis pathways including Hh pathway in the maintenance of CSCs. Purpose of this study is to reveal an essential role of Hh pathway in the maintenance of CSCs, and also to reveal a possibility of Hh pathway as a target of CSCs therapy for breast cancer patients.Materials and Methods: A human breast cancer cell line MCF-7 was used. In the present study, we estimated CD44+CD24-/low cells or side population (SP) cells as CSCs. Flow cytometric analysis and sorting were performed to detect and collect CSCs, respectively. To confirm the high tumorigenicity of CSCs, we used a MCF-7 cell xenograft mouse model in NOD/SCID mice. To assess the expression of Hh pathway-related molecules, real-time RT-PCR and fluorescent immunostaining were performed. For blockade of Hh pathway, a Hh inhibitor, cyclopamine, and small interference RNA (si-RNA) against Gli1, a trans-activator of the Hh pathway, were used. We also synthesized peptides with specific affinity for a transmembrane receptor Patched1 (Ptch1).Results: CD44+CD24-/low cells and SP cells in total MCF-7 cells were 10-25% and 1-4%, respectively and these two populations were overlapped with each other. These CSCs were highly tumorigenic, and resistant to anticancer drugs including taxanes.Hh pathway-related molecules such as Shh, a ligand of Hh pathway, and Gli1 were predominantly expressed in CSCs. Cyclopamine and Ptch1 affinitive peptides could suppress the tumorigenicity of CSCs in NOD/SCID mice xenograft transplantation model.Conclusions: Hh pathway at least partly contributes to the maintenance of CSCs in MCF-7 cells. Thus, Hh pathway may be a valuable therapeutic target for CSCs therapy for breast cancer patients. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1161.

A practical model for low-wind conditions was derived by integration of an instantaneous three-dimensional Gaussian puff equation, in which wind speed was assumed to be zero and standard deviations of a smoke (σy and σz) were expressed as a linear function of the dispersion time. When the plume spreads σy and σz were assumed to be linear functions of dispersion time, the proportionality coefficients for σy and σz) derived from the air tracer experiments were about 0.30-0.40 and 0.09-0.18 m/s, respectively.

To obtain information on the ecotoxicological properties of liquid-crystal (LC) compounds, the aquatic toxicity of selected LCs was investigated. Therefore, ten single LCs and one LC mixture were tested for their toxicity to the two standard organisms, daphnia (immobilization) and algae (growth inhibition). Water solubilities and detection limits were determined in the test media. Up to the limit of water solubility, the LCs as well as the LC mixture did not cause any adverse effects to the tested organisms.

The modeling of the resonant-tunneling hot-electron transistor (RHET) is described. In an analysis of the resonant-tunneling barrier, the Schrodinger and Poisson equations are solved self-consistently. The electron transport in the base and the collector barrier region is simulated using the Monte Carlo method, taking account of the space charge in the collector barrier. The model used includes the effect of coupled plasmon-LO phonon scattering and electron-electron scattering in the base region. The transit time is calculated in the base and the collector barrier region. The 50-nm base transient time is 0.059 ps. On the other hand, the 200-nm collector barrier transit time is larger than 1 ps due to intervalley scattering in the collector barrier region. it is shown that the collector barrier transit time can be reduced to 0.089 ps in the 50-nm collector barrier RHET at a collector-base voltage of 0.5 V. >