46 research outputs found
Superconductivity in a van der Waals layered quasicrystal
van der Waals (vdW) layered transition-metal chalcogenides are attracting
significant attention owing to their fascinating physical properties. This
group of materials consists of abundant members with various elements, having a
variety of different structures. However, all vdW layered materials studied to
date have been limited to crystalline materials, and the physical properties of
vdW layered quasicrystals have not yet been reported. Here, we report on the
discovery of superconductivity in a vdW layered quasicrystal of Ta1.6Te. The
electrical resistivity, magnetic susceptibility, and specific heat of the
Ta1.6Te quasicrystal fabricated by reaction sintering, unambiguously validated
the occurrence of bulk superconductivity at a transition temperature of ~1 K.
This discovery can pioneer new research on assessing the physical properties of
vdW layered quasicrystals as well as two-dimensional quasicrystals; moreover,
it paves the way toward new frontiers of superconductivity in thermodynamically
stable quasicrystals, which has been the predominant challenge facing condensed
matter physics since the discovery of quasicrystals almost four decades ago
Timeline analysis and wavelet multiscale analysis of the AKARI All-Sky Survey at 90 micron
We present a careful analysis of the point source detection limit of the
AKARI All-Sky Survey in the WIDE-S 90 m band near the North Ecliptic Pole
(NEP). Timeline Analysis is used to detect IRAS sources and then a conversion
factor is derived to transform the peak timeline signal to the interpolated 90
m flux of a source. Combined with a robust noise measurement, the point
source flux detection limit at S/N for a single detector row is
Jy which corresponds to a point source detection limit of the
survey of 0.4 Jy.
Wavelet transform offers a multiscale representation of the Time Series Data
(TSD). We calculate the continuous wavelet transform of the TSD and then search
for significant wavelet coefficients considered as potential source detections.
To discriminate real sources from spurious or moving objects, only sources with
confirmation are selected. In our multiscale analysis, IRAS sources selected
above can be identified as the only real sources at the Point Source
Scales. We also investigate the correlation between the non-IRAS sources
detected in Timeline Analysis and cirrus emission using wavelet transform and
contour plots of wavelet power spectrum. It is shown that the non-IRAS sources
are most likely to be caused by excessive noise over a large range of spatial
scales rather than real extended structures such as cirrus clouds.Comment: 16 pages, 19 figures, 5 tables, accepted for publication in MNRA
Calibration and Performance of the AKARI Far-Infrared Surveyor (FIS) -- Slow-Scan Observation Mode for Point Sources
We present the characterization and calibration of the Slow-Scan observation
mode of the Far-Infrared Surveyor (FIS) onboard the AKARI satellite. The FIS,
one of the two focal-plane instruments on AKARI, has four photometric bands
between 50--180 um with two types of Ge:Ga array detectors. In addition to the
All-Sky Survey, FIS has also taken detailed far-infrared images of selected
targets by using the Slow-Scan mode. The sensitivity of the Slow-Scan mode is
one to two orders of magnitude better than that of the All-Sky Survey, because
the exposure time on a targeted source is much longer. The point spread
functions (PSFs) were obtained by observing several bright point-like objects
such as asteroids, stars, and galaxies. The derived full widths at the half
maximum (FWHMs) are ~30'' for the two shorter wavelength bands and ~40'' for
the two longer wavelength bands, being consistent with those expected by the
optical simulation, although a certain amount of excess is seen in the tails of
the PSFs. The flux calibration has been performed by the observations of
well-established photometric calibration standards (asteroids and stars) in a
wide range of fluxes. After establishing the method of aperture photometry, the
photometric accuracy for point-sources is better than +-15% in all of the bands
expect for the longest wavelength.Comment: 25 pages, 7 figures, accepted publication in PAS
QOL after RT or OP for uterine cervix cancer
This study aimed to research the post-treatment quality of life (QOL) between radiotherapy (RT)- and operation (OP)-treated early cervical cancer survivors, using separate questionnaires for physicians and patients. We administered an observational questionnaire to patients aged 20–70 years old with Stages IB1–IIB cervical cancer who had undergone RT or OP and without recurrence as outpatients for ≥6 months after treatment. We divided 100 registered patients equally into two treatment groups (n = 50 each). The average age was 53 and 44 years in the RT and OP groups, respectively. The RT group included 34 and 66% Stage I and II patients, respectively, whereas the OP group included 66 and 34% Stage I and II patients, respectively. The OP group included 58% of patients with postoperative RT. Combination chemotherapy was performed in 84 and 48% of patients in the RT and OP groups, respectively. On the physicians’ questionnaire, we observed significant differences in bone marrow suppression (RT) and leg edema (OP). On the patients’ questionnaire, significantly more patients had dysuria and leg edema in the OP group than in the RT group, and severe (Score 4–5) leg edema was significantly higher in the post-operative RT group than in the OP only group. The frequency of sexual intercourse decreased after treatment in both groups. On the patients’ questionnaire, there were no significant differences between the two groups regarding sexual activity. These findings are useful to patients and physicians for shared decision-making in treatment choices. The guidance of everyday life and health information including sexual life after treatment is important
The Far-Infrared Surveyor (FIS) for AKARI
The Far-Infrared Surveyor (FIS) is one of two focal plane instruments on the
AKARI satellite. FIS has four photometric bands at 65, 90, 140, and 160 um, and
uses two kinds of array detectors. The FIS arrays and optics are designed to
sweep the sky with high spatial resolution and redundancy. The actual scan
width is more than eight arcmin, and the pixel pitch is matches the diffraction
limit of the telescope. Derived point spread functions (PSFs) from observations
of asteroids are similar to the optical model. Significant excesses, however,
are clearly seen around tails of the PSFs, whose contributions are about 30% of
the total power. All FIS functions are operating well in orbit, and its
performance meets the laboratory characterizations, except for the two longer
wavelength bands, which are not performing as well as characterized.
Furthermore, the FIS has a spectroscopic capability using a Fourier transform
spectrometer (FTS). Because the FTS takes advantage of the optics and detectors
of the photometer, it can simultaneously make a spectral map. This paper
summarizes the in-flight technical and operational performance of the FIS.Comment: 23 pages, 10 figures, and 2 tables. Accepted for publication in the
AKARI special issue of the Publications of the Astronomical Society of Japa
Superconductivity in a van der Waals layered quasicrystal
Abstract Van der Waals layered transition-metal chalcogenides are drawing significant attention owing to their intriguing physical properties. This group of materials consists of abundant members with various elements, having a variety of different structures. However, they are all crystalline materials, and the physical properties of van der Waals layered quasicrystals have never been studied to date. Here, we report on the discovery of superconductivity in a van der Waals layered quasicrystal of Ta1.6Te. The electrical resistivity, magnetic susceptibility, and specific heat of the quasicrystal unambiguously validate the occurrence of bulk superconductivity at a transition temperature of ~1 K. This discovery can promote new research on assessing the physical properties of novel van der Waals layered quasicrystals as well as two-dimensional quasicrystals; moreover, it paves the way toward new frontiers of superconductivity in thermodynamically stable quasicrystals
The effect and safety of periarticular multimodal drug injection without morphine and epinephrine in anterior cruciate ligament reconstruction
Background Periarticular multimodal drug injection (PMDI) is a safe and effective pain management technique after anterior cruciate ligament reconstruction (ACLR); however, adding morphine and epinephrine sometimes causes adverse effects. Therefore, we evaluated the efficacy of PMDI without morphine and epinephrine after ACLR. Methods This retrospective matched case-control study included patients who had undergone primary double-bundle ACLR with PMDI and were then matched one-to-one with a control group without PMDI based on sex, age, and body mass index using propensity-matched analysis. The following clinical outcomes were compared between the groups: visual analog scale (VAS) score, C-reactive protein (CRP) concentration, number of times the patients used additional analgesics, complication rate, and postoperative time to achieve straight leg raise (SLR). Results Twenty-nine patients with PMDI and 29 controls were enrolled. The VAS score at 1 day postoperatively was lower in the PMDI than the control group (1.93  ±  1.44 vs. 3.41  ±  1.75, respectively; P  < 0.001). The CRP concentration at 1 and 3 days was lower in the PMDI than the control group (0.46  ±  0.47 vs. 1.00  ±  0.69 mg/dL, P  < 0.001; and 1.93  ±  1.71 vs. 4.01  ±  2.55 mg/dL, P  < 0.001, respectively). The average number of additional analgesics used was significantly lower in the PMDI than the control group. There were no significant differences in the frequency of occurrence of postoperative complications between the two groups. The number of patients who could achieve SLR within 1 day was 27/29 (93%) in PMDI group, which was significantly higher than the control group (12/29, 41%) ( P  < 0.001). Conclusion PMDI without morphine and epinephrine after ACLR reduced patients’ subjective pain level, objective inflammatory response without complications and enabled patients to achieve early functional recovery