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This report describes the actuator functionality of a ceramic composite that uses the volume change caused by the insulator–metal (I–M) transition of VO2. When an electrical field was applied at 295 K, 50 vol. %-VO2/Al2O3 ceramic composite underwent the I–M transition because the VO2 powder dispersed in the composite became metallic. Simultaneous measurement of I–V characteristics and linear strain demonstrated that this I–M transition was accompanied by a positive strain. This strain increased with increase in the limit current value, which limits excessive current flow after transition. The strain exceeded 1300 ppm at maximum. Its magnitude corresponded to the volume change obtained from thermal expansion measurements on the composite. This composite performs a volume-change-driven actuator function that is distinct from the strain-driven counterpart of piezoelectric materials. [ABSTRACT FROM AUTHOR]

Proton–3He scattering is one of the good probes to study the T = 3/2 channel of three– nucleon forces. We have measured 3He analyzing powers for p−3He elastic scattering with the polarized 3He target at 70 and 100 MeV. In the conference the data were com- pared with the theoretical predictions based on the modern nucleon–nucleon potentials. Large discrepancies were found between the data and the calculations at the angles where the 3He analyzing power takes the minimum and maximum values.

The observation of spinon excitations in the S = 1 2 triangular antiferromagnet Ca3ReO5Cl2 reveals a quasi-one-dimensional (1D) nature of magnetic correlations, in spite of the nominally 2D magnetic structure. This phenomenon is known as frustration-induced dimensional reduction. Here, we present high-field electron spin resonance spectroscopy and magnetization studies of Ca3ReO5Cl2, allowing us not only to refine spin-Hamiltonian parameters, but also to investigate peculiarities of its low-energy spin dynamics. We argue that the presence of the uniform Dzyaloshinskii-Moriya interaction (DMI) shifts the spinon continuum in momentum space and, as a result, opens a zero-field gap at the Γ point. We observed this gap directly. The shift is found to be consistent with the structural modulation in the ordered state, suggesting this material as a perfect model triangular-lattice system, where a pure DMI-spiral ground state can be realized. Frustration-induced dimensional reduction is manifested in lower dimensionality of magnetic correlations compared to that of the magnetic structure. Here the authors demonstrate the role of the uniform Dzyaloshinskii-Moriya interaction in the recently synthesized material Ca3ReO5Cl2 exhibiting dimensional reduction. [ABSTRACT FROM AUTHOR]

Objectives Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality. Design Retrospective multinational study including SCN diagnosed between 1990 and 2014. Results 2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2-200)), 9% had resection beyond 1 year of follow-up (3 years (1-20), size at diagnosis: 25 mm (4-140)) and 39% had no surgery (3.6 years (1-23), 25.5 mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271 ), size increased in 37% (growth rate: 4 mm/ year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was [ABSTRACT FROM AUTHOR]

WO3-xFx(x ≤ 0.45) perovskite-like oxyfluorides were prepared by a chemically reducing fluorination route using the polymer polytetrafluoroethylene (teflon). The symmetry of the crystal structures of WO3-xFx changes from monoclinic to tetragonal to cubic as the fluorine content increases. Fluorine doping changes insulating WO3 to a metallic conductor, and superconductivity (Tc = 0.4 K) was discovered in the samples with fluorine contents of 0.41 ≤ x ≤ 0.45. This easy fluorination method may be applicable to other systems and presents an opportunity for finding new oxyfluoride superconductors. [ABSTRACT FROM AUTHOR]

This study investigated the effects of pedal frequency on the slow component of pulmonary oxygen uptake (VO2) kinetics during heavy exercise at the same relative intensity. We hypothesized that higher pedal frequency (expected to enhance fast-twitch muscle fiber recruitment) would be associated with greater slow component amplitude (A's), surface electromyography (normalized root mean square; RMS) and blood lactate concentration ([lactate]). Eight subjects performed square-wave transitions to heavy exercise at 35 and 115rpm. Furthermore, alternated cadences square-wave transitions (35-115 rpm) were performed to examine the potential effects of additional fast-twitch muscle fiber recruitment on the slow component. Significance was accepted when P<0.05. The A's was greater at higher cadences (0.58±0.08 and 0.70±0.09 L.min-1 at 115 and 35-115 rpm, respectively) than at 35 rpm (0.35±0.04 L.min-1 ). Greater EMG increase over time (ΔRMS(10-3min)) and [lactate] were observed at 115 and 35-115 rpm compared with 35 rpm. There was a significant correlation between A's and overall ΔRMS(10-3min) for all pedal frequencies combined (r=0.63; P=0.001). Pedal frequency had no effect on time constants or time delays. These findings are consistent with the concept that progressive recruitment of muscle fibers is associated with the VO2 slow component. [ABSTRACT FROM AUTHOR]

Abstract: Motivated by the recent discovery of a “checkerboard”-type charge ordering in Na x CuO2Cl2 high-T c superconductors, the doping dependence of T c has been carefully examined in this compound to clarify whether there is any anomaly in the phase diagram, which has been observed at 1/8-doping in the isostructural La2CuO4-based superconductors with a different “stripe”-type ordering. It is shown that the improved sample preparation can increase the maximum T c by 3K, and that there is not any anomalous suppression of T c at any specific doping in Na x CuO2Cl2. Taking into account the recent STM/STS observations of the checkerboard charge ordering, its impact on superconductivity is discussed. [Copyright &y& Elsevier]