262 research outputs found
Aqueous Gel Permeation Chromatography of Electrolytes and Polyelectrolytes. III. Determination of Selectivity in Counterion Binding to Polyelectrolytes
Examining Minimal Important Change of the Self-Assessment Scale of Clinical Reasoning in Occupational Therapy
The purpose of the study was to establish and quantify the minimal important change (MIC) value necessary to determine gains or losses in clinical reasoning during student fieldwork assignments as measured by the Self-Assessment of Clinical Reasoning in Occupational Therapy (SA-CROT). This multicenter prospective longitudinal study was conducted with students on their occupational therapy fieldwork in Japan. Two anchor-based methods were used to estimate the MIC values: a receiver operating characteristic-based method and a predictive modeling-based method. The MIC was adjusted based on the percentage of participants who exhibited improvement. Administered were the SA-CROT and the Global Rating of Change (GRC) scale as an anchor. A total of 111 students from 11 occupational therapy educational programs in Japan responded (response rate 29%). Overall, there was a significant difference (p \u3c .001, effect size was r = .80) in SA-CROT before and after fieldwork, and 81% of students showed improvement in the GRC scale. The adjusted MIC value was 3.69, with 95% confidence interval of 2.29–4.97. This anchor-based, adjusted MIC value is the most reliable value to interpret the changes in SA-CROT before and after fieldwork. The SA-CROT\u27s MIC value can be used as a cut-off point from a learner-centered perspective when considering educational methods and environments in fieldwork
Excitonic Aharonov-Bohm Effect in Isotopically Pure 70Ge/Si Type-II Quantum Dots
We report on a magneto-photoluminescence study of isotopically pure 70Ge/Si
self-assembled type-II quantum dots. Oscillatory behaviors attributed to the
Aharonov-Bohm effect are simultaneously observed for the emission energy and
intensity of excitons subject to an increasing magnetic field. When the
magnetic flux penetrates through the ring-like trajectory of an electron moving
around each quantum dot, the ground state of an exciton experiences a change in
its angular momentum. Our results provide the experimental evidence for the
phase coherence of a localized electron wave function in group-IV Ge/Si
self-assembled quantum structures.Comment: 4 pages, 4 figure
Treatment Outcomes of Pulmonary Metastases from Head and Neck Squamous Cell Carcinoma
Although the lung is the most common site of distant metastases from head and neck squamous cell carcinoma (HNSCC), the number of reports about the effects of pulmonary metastasectomy for the treatment of lung metastasis from HNSCC is limited. Metachronous pulmonary metastases were detected in 45 HNSCC patients at Kumamoto University Hospital from 1998 to 2018. Twenty-two patients underwent an operative resection (Ope group) and 23 underwent chemotherapy (Chemo group). The 3-year overall survival (OS) rate and median OS were evaluated. The effects of adjuvant chemotherapy after pulmonary metastasectomy and of new drugs (cetuximab and nivolumab), in the chemo group were also assessed. The 3-year OS rates and median OS were: Ope, 66.1% and 31.5 months; Chemo, 39.7% and 18 months, respectively. In the Ope group, addi-tional recurrences were significantly fewer in the patients who underwent adjuvant chemotherapy post-surgery versus the patients who underwent surgery alone (p = 0.013). In the Chemo group, the 3-year OS rate of the patients who received new drugs was significantly better than that of the patients who did not (p = 0.021). Adjuvant chemotherapy after pulmonary metastasectomy may be a preferable treatment option for preventing recurrences. Cetuximab and nivolumab have a potential to improve OS
New readout and data-acquisition system in an electron-tracking Compton camera for MeV gamma-ray astronomy (SMILE-II)
For MeV gamma-ray astronomy, we have developed an electron-tracking Compton
camera (ETCC) as a MeV gamma-ray telescope capable of rejecting the radiation
background and attaining the high sensitivity of near 1 mCrab in space. Our
ETCC comprises a gaseous time-projection chamber (TPC) with a micro pattern gas
detector for tracking recoil electrons and a position-sensitive scintillation
camera for detecting scattered gamma rays. After the success of a first balloon
experiment in 2006 with a small ETCC (using a 101015 cm
TPC) for measuring diffuse cosmic and atmospheric sub-MeV gamma rays (Sub-MeV
gamma-ray Imaging Loaded-on-balloon Experiment I; SMILE-I), a (30 cm)
medium-sized ETCC was developed to measure MeV gamma-ray spectra from celestial
sources, such as the Crab Nebula, with single-day balloon flights (SMILE-II).
To achieve this goal, a 100-times-larger detection area compared with that of
SMILE-I is required without changing the weight or power consumption of the
detector system. In addition, the event rate is also expected to dramatically
increase during observation. Here, we describe both the concept and the
performance of the new data-acquisition system with this (30 cm) ETCC to
manage 100 times more data while satisfying the severe restrictions regarding
the weight and power consumption imposed by a balloon-borne observation. In
particular, to improve the detection efficiency of the fine tracks in the TPC
from 10\% to 100\%, we introduce a new data-handling algorithm in
the TPC. Therefore, for efficient management of such large amounts of data, we
developed a data-acquisition system with parallel data flow.Comment: 11 pages, 24 figure
Coherence of a field-gradient-driven singlet-triplet qubit coupled to many-electron spin states in 28Si/SiGe
Engineered spin-electric coupling enables spin qubits in semiconductor
nanostructures to be manipulated efficiently and addressed individually. While
synthetic spin-orbit coupling using a micromagnet is widely used for driving
qubits based on single spins in silicon, corresponding demonstration for
encoded spin qubits is so far limited to natural silicon. Here, we demonstrate
fast singlet-triplet qubit oscillation (~100 MHz) in a gate-defined double
quantum dot in Si/SiGe with an on-chip micromagnet with which we show
the oscillation quality factor of an encoded spin qubit exceeding 580. The
coherence time * is analyzed as a function of potential
detuning and an external magnetic field. In weak magnetic fields, the coherence
is limited by fast noise compared to the data acquisition time, which limits
* < 1 s in the ergodic limit. We present evidence of
sizable and coherent coupling of the qubit with the spin states of a nearby
quantum dot, demonstrating that appropriate spin-electric coupling may enable a
charge-based two-qubit gate in a (1,1) charge configuration
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