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Here, we present the first systematic study on the temperature dependence of the extension of the superconducting proximity effect in a 1–2 atomic layer thin metallic film, surrounding a superconducting Pb island. Scanning tunneling microscopy/spectroscopy (STM/STS) measurements reveal the spatial variation of the local density of state on the film from 0.38 up to 1.8 K. In this temperature range the superconductivity of the island is almost unaffected and shows a constant gap of a 1.20 ± 0.03 meV. Using a superconducting Nb-tip a constant value of the proximity length of 17 ± 3 nm at 0.38 and 1.8 K is found. In contrast, experiments with a normal conductive W-tip indicate an apparent decrease of the proximity length with increasing temperature. This result is ascribed to the thermal broadening of the occupation of states of the tip, and it does not reflect an intrinsic temperature dependence of the proximity length. Our tunneling spectroscopy experiments shed fresh light on the fundamental issue of the temperature dependence of the proximity effect for atomic monolayers, where the intrinsic temperature dependence of the proximity effect is comparably weak.

Background: To treat symptomatic benign prostatic hyperplasia α1-adrenoceptor antagonists with little antagonism at α1b-adrenoceptor were used to avoid orthostatic hypotension. In benign prostatic hyperplasia tissues α1D-adrenoceptor are thought to predominate, but in the Japanese experience, either α1A- or α1D- adrenoceptor antagonists can alleviate benign prostatic hyperplasia symptoms. We hypothesized that prostatic expression of α1A- and α1D-adrenoceptor varies quantitatively between patients. Materials and Methods: We immunohistochemically localized α1A- and α1D-adrenoceptor within benign prostatic hyperplasia tissues, and quantitated mRNA expression for these subtypes by real-time quantitative reverse transcription-polymerase chain reaction. Results: Immunohistochemistry detected both subtypes in stromal but not detected epithelial cells. Copy numbers of α1A-adrenoceptor mRNA in benign prostatic hyperplasia tissue were significantly higher than those of α1D-adrenoceptor mRNA. Among patients; the ratio of α1A- to α1D-adrenoceptor mRNA ranged from 1.0 to 8.4. Conclusion: An ideal therapeutic antagonist for treating benign prostatic hyperplasia symptoms should block both α1A- and α1D-adrenoceptor Keywords: Adrenoceptor subtypes; Benign prostatic hyperplasia; Quantitative reverse transcription-polymerase chain reaction DOI: 10.3126/jpn.v1i1.4439Journal of Pathology of Nepal (2011) Vol.1, 1-7

More than 10 ^7 electrons and 10 ^5 positrons with energy less than a few eV were confined simultaneously for the first time in a compact magnetic mirror trap with plugging potentials. The exponential decay time constant of the confined positrons exceeded 70 ms at the beginning of the simultaneous confinement. Particle simulations in the early stages of the mixing process were also conducted. The results obtained in the experiments and simulations suggested that an improved setup would make it possible to investigate the unexplored field of low-energy electron–positron plasmas experimentally.

Two-mode squeezed states, generated via non-degenerate parametric down-conversion, are invariably revealed via their entangled vacuum or correlated thermal fluctuations. Here, two-mode thermal squeezed states, generated in an electromechanical system, are made bright by means of degenerate parametric amplification of their constituent modes to the point where they are almost perfect, even when seeded from low intensity non-degenerate parametric down-conversion. More dramatically, activating the degenerate parametric resonances of the underlying modes yields perfect correlations which can be resolved via the coordinated switching of their phase bi-stable vibrations, without recourse to monitoring their thermal fluctuations. This ability to enhance the two-mode squeezed states and to decipher them without needing to observe their intrinsic noise is supported by both analytical and numerical modelling and it suggests that the technical constraints to making this phenomenon more widely available can be dramatically relaxed.

Long-term climate experiments up to the year 2300 have been conducted using two full-scale complex Earth system models (ESMs), CESM1(BGC) and MIROC-ESM, for a CO _2 emissions reduction pathway, termed Z650, where annual CO _2 emissions peak at 11 PgC in 2020, decline by 50% every 30 years, and reach zero in 2160. The results have been examined by focusing on the approximate linear relationship between the temperature increase and cumulative CO _2 emissions. Although the temperature increase is nearly proportional to the cumulative CO _2 emissions in both models, this relationship does not necessarily provide a robust basis for the restriction of CO _2 emissions because it is substantially modulated by non-CO _2 forcing. CO _2 -induced warming, estimated from the atmospheric CO _2 concentrations in the models, indicates an approximate compensation of nonlinear changes between fast-mode responses to concentration changes at less than 10 years and slow-mode response at more than 100 years due to the thermal inertia of the ocean. In this estimate, CESM1(BGC) closely approximates a linear trend of 1.7 °C per 1000 PgC, whereas MIROC-ESM shows a deviation toward higher temperatures after the emissions peak, from 1.8 °C to 2.4 °C per 1000 PgC over the range of 400–850 PgC cumulative emissions corresponding to years 2000–2050. The evolution of temperature under zero emissions, 2160–2300, shows a slight decrease of about 0.1 °C per century in CESM1(BGC), but remains almost constant in MIROC-ESM. The fast-mode response toward the equilibrium state decreases with a decrease in the airborne fraction owing to continued CO _2 uptake (carbon cycle inertia), whereas the slow-mode response results in more warming owing to continued heat uptake (thermal inertia). Several specific differences are noted between the two models regarding the degree of this compensation and in some key regional aspects associated with sustained warming and long-term climate risks. Overall, elevated temperatures continue for at least a few hundred years under zero emissions.

We report angle-resolved photoemission (ARPES) measurements, density functional and model tight-binding calculations on Ba _2 IrO _4 (Ba-214), an antiferromagnetic ( T _N = 230 K) insulator. Ba-214 does not exhibit the rotational distortion of the IrO _6 octahedra that is present in its sister compound Sr _2 IrO _4 (Sr-214), and is therefore an attractive reference material to study the electronic structure of layered iridates. We find that the band structures of Ba-214 and Sr-214 are qualitatively similar, hinting at the predominant role of the spin–orbit interaction in these materials. Temperature-dependent ARPES data show that the energy gap persists well above T _N , and favor a Mott over a Slater scenario for this compound.

A small-scale synthesis of the four sphingosine stereoisomers (D-erythro, L-erythro, D-threo, and L-threo) and lignoceroyl D- and L-erythro-sphingosines, which is suitable for synthesis of tritium-labeled compounds, is described. Ethyl DL-erythro-2-acetamino-3-hydroxy-4t-octadecenoate was esterified with L(+)-acetylmandeloyl chloride and the two diastereomers obtained were separated from each other by thin-layer or column chromatography. Each diastereomer was subjected to ethanolysis to obtain ethyl D- or L-erythro-2-amino-3-hydroxy-4t-octadecenoate which was then reduced with LiAlH4 or NaBH4 to yield D- or L-erythro-sphingosine. D-erythro-[1-3H]Sphingosine with high specific activity was prepared by using LiAl3H4 in the last step. D- and L-threo-sphingosines were synthesized from ethyl DL-threo-2-acetamino-3-hydroxy-4t-octadecenoate by using a similar procedure.Ceramide (lignoceroyl sphingosine) was prepared either by acylating sphingosine or by the following new method. Ethyl DL-erythro-2-amino-3-hydroxy-4t-octadecenoate was converted to the N-lignoceroyl derivative and esterified with L(+)-acetylmandeloyl chloride. The two diastereomers obtained were separated and each isomer was treated with a catalytic amount of sodium ethoxide. One of the products, ethyl D-erythro-2-lignoceroylamino-3-hydroxy-4t-octadecenoate, was reduced with NaBH4 to yield ceramide. N-palmitoyl DL-erythro-sphingosine was also prepared using an identical procedure. N-lignoceroyl D-erythro-[1-3H]sphingosine was prepared by NaB3H4 reduction of the corresponding amide ester. A doubly labeled ceramide, [1-14C]lignoceroyl [1-3H]sphingosine, containing high specific activity, was prepared by mixing the above N-lignoceroyl D-erythro-[1-3H]sphingosine and N-[1-14C]lignoceroyl D-erythro-sphingosine. The conversion of the doubly labeled ceramide to 3-keto derivative is also described.

The relationship among tensile strength, Vickers hardness and dislocation density for two types of 11Cr-ferritic/martensitic steel (PNC-FMS) was investigated after aging at temperatures between 400 and 800°C up to 45,000h and after neutron irradiation. A correlation between tensile strength and Vickers hardness was expressed empirically. The linear relationship for PNC-FMS wrapper material was observed between yield stress and the square of dislocation density at RT and aging temperature according to Bailey–Hirsch relation. Therefore, it was clarified that the correlation among dislocation density, tensile strength and Vickers hardness to aging temperature was in good agreement. On the other hand, the relationship between tensile strength ratio when materials were tested at aging temperature and Larson–Miller parameter was also in excellent agreement with aging data between 400 and 700°C. It was suggested that this correlation could use quantitatively for separately evaluating irradiation effects from neutron irradiation data containing both irradiation and aging effects.