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No clinically relevant biomarker has been identified for predicting the response of esophageal squamous cell carcinoma (ESCC) to chemoradiotherapy (CRT). Herein, we established a CT-based radiomics model with artificial intelligence (AI) to predict the response and prognosis of CRT in ESCC. A total of 44 ESCC patients (stage I-IV) were enrolled in this study; training (n = 27) and validation (n = 17) cohorts. First, we extracted a total of 476 radiomics features from three-dimensional CT images of cancer lesions in training cohort, selected 110 features associated with the CRT response by ROC analysis (AUC ≥ 0.7) and identified 12 independent features, excluding correlated features by Pearson’s correlation analysis (r ≥ 0.7). Based on the 12 features, we constructed 5 prediction models of different machine learning algorithms (Random Forest (RF), Ridge Regression, Naive Bayes, Support Vector Machine, and Artificial Neural Network models). Among those, the RF model showed the highest AUC in the training cohort (0.99, p

A new type of minicapture pump which acts on noble gas species and operates in combination with a getter pump has been developed. We call it the “entrapment pump.” The pump is a single Penning cell (φ7×h5 mm anode) whose cathode can be heated during pumping to more than 1000 °C. After the getter pump is working, the pump cathode is activated by heating. Then, in a second step, the pump is operated by applying the high voltage and residual noble gas (argon) pumped by burial, not sputtering. Weakly buried noble gas within the pump cell is re-emitted by intentional heating. This is performed during every pumpdown following any exposure to atmospheric air and the surface of the cathode is thereby cleaned and renewed. As a result, noble gas atoms are buried in a pure metal surface when high voltage is applied and no burst of contamination species is generated from the cathode surface when the pump is initially started. The re-emission of previously pumped noble gas, acting as a gas source, is also minimized fo...

By using a newly developed beryllium–copper (BeCu)‐alloy ConFlat flange to house the hot‐cathode ion source, a remarkable decrease in the outgassing from a quadrupole residual gas analyzer (RGA) has been achieved. The reduction in outgassing between the new BeCu‐flanged RGA and an ordinary stainless‐steel RGA of otherwise similar design was a factor of 60 or more in the 10−9 Pa total pressure range. From these results, the possibility of high accuracy residual gas analysis below 10−9 Pa is introduced.

Up‐converted beams of a conventional quadrupled Nd:YAG laser by anti‐Stokes Raman scattering in hydrogen are characterized as a vacuum ultraviolet light source. The beams diverge with the increase of the hydrogen pressure and also with the increase of the order of anti‐Stokes scattering. Although the profiles of anti‐Stokes beams vary from a Gaussian‐like shape to a typical ring shape, the maximum energy conversion is always obtained with a near‐Gaussian beam profile. The output energy ranges from 5.9 mJ for the first‐order anti‐Stokes wave (240 nm) to 8 μJ for the ninth‐order anti‐Stokes wave (133 nm). The energy of the sixth‐order anti‐Stokes wave (160 nm) fluctuates ±45% of the average output energy. The beam characteristics are described well by a model on the basis of phase matching between four waves related to each Raman process.

An apparatus for measuring the peel adhesion behavior is developed on the basis of the circular motion of the compound pendulum. The peel force versus peel rate characteristics at the increasing and decreasing rates of peeling can be measured in a half cycle of rotation of the pendulum. A personal computer plays the important roles of operating the automated apparatus and processing data in real time. To test practical performance of the apparatus, the relation between peel force and rate of peeling was investigated for various pressuresensitive adhesive (PSA) tapes over a wide peel rate range. The respective curves in peel force versus peel rate in the increasing and decreasing rate processes are consistent with each other in the rate regions where cohesive or interfacial failures occur; while in the transition region between their failures, it appears that a peel hysteresis exists. Furthermore, the conventional testing under constant rate was repeated, and good agreement with the results from the present apparatus was obtained.

Temporally and spatially resolved measurements of stimulated vibrational Raman scattering in hydrogen showed two types of Raman process during the course of pulsed excitation. One is a process coupled with the first Stokes wave which has a smaller divergence and a higher peak intensity. The other, arising later in coincidence with the second Stokes wave, induces beam break-up of the first Stokes wave to a ring structure. Generation of higher order anti-Stokes waves is mainly induced by the former process.

The viscoelastic anomaly found at 208 K for as-polymerized polytetrafluoroethylene (PTFE) is investigated on the basis of thermal treatment dependence of mechanical spectra. The loss intensity and relaxation strength of the anomaly tend to decrease at annealing temperatures much lower than the melting point. The structural region relevant to the anomaly can be rearranged in more ordered states on annealing; accordingly, the loss peak of the crystalline dispersion is intesified, although that of the amorphous γ-relaxation remains nearly unchanged. The anomaly originates from the intermediate or paracrystalline regions, many of which are included in the virgin samples; segmental motions like local mode relaxation are considered.

High quality window/plate shaped CaF2 single crystals have developed by vertical Bridgman method of with diameters of 50, 100, and 200 mm and 210 mm width, 200mm length. The CaF2 windows of 30mm diameter obtained from big crystals have evaluated the transmission spectra from 120 nm to 220nm by single beam VUV spectrometer. We could obtain bulk transmission spectra by subtracting surface reflection loss between tow kinds of thickness samples. The results show flat spectra without distinct absorption from 130nm to 220nm. In laser-damage tests with the fourth harmonic (4ω) of a Nd:YAG laser below 1NW/cm2 at the CaF2 window, a stable output of 600mW was obtained. ArF laser irradiation of 50mJ/cm2 and 6X104 pulses was tried and the degradation in transmission from 130nm to 220nm not observed. These data show that the radiation hardness of our CaF2 crystals is promising for deep ultra-violet laser applications.

The Hall effect of a metallic Langmuir–Blodgett film based on bisethylenedioxytetrathiafulvalene complex of decyltetracyanoquinodimethane has been investigated using a double ac Hall method. The polarity of the Hall coefficient is positive over the measuring temperature range. The carrier density is of the order of 1021 cm−3, almost independent of temperature, and the Hall mobility, of around 0.05 cm2 (V s)−1 at room temperature, is in a single activated process. The Hall results have been interpreted with an inhomogeneous structure model, and support that metallic domains are developed throughout the whole sample.

Thermoelectric power in highly conductive Langmuir-Blodgett films of tridecylmethylammonium-Au(dmit)2 (σRT 30−50 Scm) was examined. The metallic nature of this material is suggested from the results of the thermoelectric power. The resistivity increased with aging, however the thermoelectric power was invariant. These results suggest that the metallic nature of the film is preserved after aging. The newly developed conductive LB films of didecyldimethylammonium-Pd(dmit)2 showed a high conductivity of 5.1 Scm at room temperature. From the temperature dependence of the conductivity, semiconductor-like transport was suggested.

The conductivity of CdS-Se sintered film increases irreversibly about 109-fold with vacuum heat treatment from 100° C to 200° C. The mechanism of such a large variation has been studied using highly sensitive Hall effect and conductivity measurements. The obtained results can be analyzed by the grain-boundary potential-barrier model with the aid of the charge neutrality condition for the grains, the maximum allowable values of surface potential and potential barrier height, and the density of interface states. Increase in conductivity of 8 orders of magnitude is brought about by increase in the free electron density, which occurs in two steps: in the low-temperature region, the release of trapped electrons from the surface state occurs due to desorption of chemisorbed oxygen; in the high-temperature region, the increase in effective doping density through the decrease in acceptor density occurs due to the release of occluded oxygen from the bulk crystallites near the surface. The mobility of free electrons contributes to an increase of one order of magnitude in conductivity, which decreases once to a minimum and then increases. The variation in mobility is attributed to the barrier height at the grain boundary which is produced by trapped electrons at the intrinsic interface state.

Hall effect measurements of pyrolytic Langmuir-Blodgett films based on a biphenyl-type polyimide have been done using a double frequency method. The Hall coefficient had a negative sign over the measuring temperature range; an electron density of 1021 cm-3 and a Hall mobility of around 0.5 cm2(Vs)-1 could be estimated on the assumption of a one-carrier conduction. The Hall mobility is characterized by a single activated process with 5.4 meV.

A double AC apparatus having new functions is described. So far, in a highly sensitive double AC apparatus, the false signal generation due to nonlinearity at terminal junctions of the specimen and induced emf has been a decisive drawback. In the present apparatus, which eliminates the induced emf in situ by using specially designed transformers, the false signal can be completely removed. This result enables us to measure, with high precision, the Hall emf down to a voltage level comparable to the thermal noise of the specimen. In addition, the current shunting effect by capacitances in the region of high specimen resistance is reduced by the proper arrangement of lead wire and by the bootstrapping technique. The upper limit of specimen resistance for which the Hall effect is measurable with the double AC method is extended up to 100 G Ω.

Higher-order anti-Stokes pulses in the VUV region were enhanced efficiently by steepening the leading edge of a pump pulse with the use of a Pockels cell. The shortest observed wavelength of 122 nm resulted from the 10th-order anti-Stokes pulse of a KrF excimer laser and had a peak power of 10 kW, while the 5th-order anti-Stokes pulse at 164 nm had powers of greater than 1 MW.

Electronic transport measurements are reported for Langmuir-Blodgett (LB) films of tridecylmethylammonium-Au(dmit)2 for 300-4 K. The conductivity after electrochemical oxidation is 30-50 S/cm at room temperature, increases with decreasing temperature, and begins decrease at about 200 K. The conductivity at lower temperatures is explained by two-dimensional variable range hopping (2D VRH). The thermoelectric power (S) is positive and well fitted by a linear combination of the temperature dependence of 2D VRH (S v\proptT 1/3) and that of metal (S m\proptT). These results can be explained by a model in which highly conductive metallic regions are separated by thin weakly conductive regions. The UV/visible absorption spectra and the X-ray diffraction patterns indicate that a large structural change occurs accompanied by electrochemical oxidation.

Thermoelectric power and electrical conductivity in Langmuir-Blodgett (LB) films of tridecylmethylammonium-Au(dmit)2 have been measured in the temperature range of 300 to 125 K. The conductivity in the lateral direction of the LB films is 30 S/cm at room temperature. The conductivity increases down to around 200 K, and decreases below that temperature. The thermoelectric power is positive and its temperature dependence shows a metallic behavior in the temperature range measured. The average value in thermoelectric power at room temperature is 20 µV/K.

The temperature dependence of the electron mobility in molybdenum ditelluride single crystals has been measured in the temperature range between 8 K and 830 K. The results are examined with the three dimensional Schmid's model and two dimensional Fivaz's model for homopolar optical phonon scattering. The temperature dependence in high temperature region above about 350 K is well explained by Schmid's model. The resistivity anisotropy ρ //c /ρ ⊥c is also presented.

The 1st magnetocrystalline anisotropy constant K 1 was determined from the torque curve of the (001) plane for Ni–Rh and –V. Measurements were carried out at normal pressure and under pressures up to 7 kbar. Measurement temperature ranged from 4.2 K to room temperature at normal pressure and pressure effect was measured only at 77 K. The results for Ni–Rh is successfully explained by the band model in which we assume the linear change in spin-orbit parameter and the monotonical change in exchange splitting with salute content. However, those for Ni–V cannot be explained with the model. This is considered due to the appearance of the virtual bound states.

Pressure effects on the spontaneous magnetization at 0 K were estimated from the forced magnetostriction. The results were analysed on the basis of the itinerant electron model, which takes both d band widening and s-d transfer into account. The pressure effect dµ/d p is anisotropic through the direction of the magnetization. For pure Ni, dµ/d p results only from the s-d transfer. For the positive dµ/d p of Ni–V alloy, an explanation was made with the virtual bound levels.

The experiments of the electrical resistivity and magnetoresistance effect were performed on undoped p-type ZnCr2Se4 single crystals and Cu-substituted ZnCr2Se4 single crystals between room temperature and below T N. Hall effect was also measured with Cu-substituted ZnCr2Se4 between 300 K and 4K. Remarkable variations were observed at ∼114 K and ∼22 K in the temperature dependence of electrical resistivity of any undoped samples. Negative magnetoresistance was also observed below ∼110 K and it increases with a peak in the vicinity of T N. Anisotropy of the resistivity with respect to the crystallographic axes was recognized though it was small. High sensitive measurement of differential thermal analysis was carried out and anomalies of its signal were observed at ∼110 K, ∼64 K, ∼36 K and ∼22 K. These results seem to indicate the interdependence between magnetic and electrical properties which is the characteristic of ZnCr2Se4.

When multiple internal reflections are taken into account, low-absorption (high-transmissivity) measurement must be corrected with the reflectivity. With this in mind, a spectrophotometer for both transmissivity and reflectivity measurement has been developed. It covers measurement from the near infrared to the ultraviolet (1.1 to 6.2 eV). Since the spectrophotometer aims at especially high transmissivity measurement, it requires low stray light, fine adjustment of the optical system and low-noise electronics. This paper discusses its principle, its performance and the method of correction for effective operation. The spectrophotometer can measure the transmissivity T from 0.0004 to 0.998 and the reflectivity R from 0.0005 to 0.998 in the spectral region from 1.1 to 5.1 eV, and T from 0.003 to 0.995 and R from 0.0008 to 0.995 in the region from 5.2 to 6.2 eV.

Photoemission was observed from shallower levels than the valence band maximum. This supports the model that surface levels exist in the band gap and electrons are emitted from these levels. On the whole, the yield curve of pure KCl is divided into two parts: small yields below 4.0 eV and a structured exponential rise above 4.0 eV. From this, the Fermi level of the surface is estimated to be situated 4.0 eV below the vacuum level. The exponential rise is modified by structures such as shoulder and dip. Compared with the curve of pure KCl, the yield curve of coloured KCl suggests that the photoemission reflects surface rather than bulk properties.

The reflectivity of KCl in the region from 1.1 to 6.2 eV has no structure and increases slightly with photon energy. Moreover, it depends little on the origin of the specimen. The optical density of KCl is small and increases linearly with photon energy in the region up to 5.5 eV. In this region, the optical density is almost independent of the thickness of the specimen and is therefore attributed to absorption at the surface. At 5.5 eV, however, the optical density rises steeply and depends on the thickness. However, the value extrapolated to zero thickness connects smoothly with the optical density below 5.5 eV. In KCl, the surface levels cover the band gap of the bulk. The levels which lie more than 4.0 eV below the vacuum level are occupied by electrons, and there seems to be a continuous and homogeneous distribution of the surface level.