150 research outputs found
Label Selection Approach to Learning from Crowds
Supervised learning, especially supervised deep learning, requires large
amounts of labeled data. One approach to collect large amounts of labeled data
is by using a crowdsourcing platform where numerous workers perform the
annotation tasks. However, the annotation results often contain label noise, as
the annotation skills vary depending on the crowd workers and their ability to
complete the task correctly. Learning from Crowds is a framework which directly
trains the models using noisy labeled data from crowd workers. In this study,
we propose a novel Learning from Crowds model, inspired by SelectiveNet
proposed for the selective prediction problem. The proposed method called Label
Selection Layer trains a prediction model by automatically determining whether
to use a worker's label for training using a selector network. A major
advantage of the proposed method is that it can be applied to almost all
variants of supervised learning problems by simply adding a selector network
and changing the objective function for existing models, without explicitly
assuming a model of the noise in crowd annotations. The experimental results
show that the performance of the proposed method is almost equivalent to or
better than the Crowd Layer, which is one of the state-of-the-art methods for
Deep Learning from Crowds, except for the regression problem case.Comment: 15 pages, 1 figur
Measurement of Internal Friction for Tungsten by the Curve Vibrating Method with Variation of Voltage and Temperature
Application of a curved vibrating wire method (CVM) to measure gas viscosity has been widely used. A fine Tungsten wire with 50 mm of diameter is bent into a semi-circular shape and arranged symmetrically in a magnetic field of about 0.2 T. The frequency domain is used for calculating the viscosity as a response for forced oscillation of the wire. Internal friction is one of the parameter in the CVM which is has to be measured beforeahead. Internal friction coefficien for the wire material which is the inverse of the quality factor has to be measured in a vacuum condition. The term involving internal friction actually represents the effective resistance of motion due to all non-viscous damping phenomena including internal friction and magnetic damping. The testing of internal friction measurement shows that at different induced voltage and elevated temperature at a vacuum condition, it gives the value of internal friction for Tungsten is around 1 to 4 10-4
Steroid psychosis in a polyarteritis nodosa patient successfully treated with risperidone: tracking serum brain-derived neurotrophic factor levels longitudinally
We previously reported a case in which steroid-induced psychosis was eliminated with risperidone treatment in a patient with polyarteritis nodosa (PN). In the present report, we longitudinally tracked the serum levels of brain-derived neurotrophic factor (BDNF). We found that corticosteroid lowered serum BDNF levels, and improvement of psychiatric symptoms was intact with the serum BDNF levels seen in the patients
Delayed Follow-up Visits and Thyrotropin Among Patients With Levothyroxine During the COVID-19 Pandemic
Context: The indirect effects of the COVID-19 pandemic on clinical practice have received great attention, but evidence regarding thyroid disease management is lacking. Objective: We aimed to investigate the association between delayed follow-up visits during the pandemic and their serum thyrotropin (TSH) levels among patients being treated with levothyroxine. Methods: This study included 25 361 patients who made a follow-up visit as scheduled (n = 9063) or a delayed follow-up visit ( 4.5 mIU/L, aRR [95% CI] = 1.72 [1.60-1.85]; and TSH > 10 mIU/L, aRR [95% CI] = 2.38 [2.16-2.62]). Conclusion: A delayed follow-up visit during the COVID-19 pandemic was associated with less well-controlled TSH among patients with levothyroxine
Spatiotemporal Control of Ice Crystallization in Supercooled Water via an Ultrashort Laser Impulse
Takahashi H., Kono T., Sawada K., et al. Spatiotemporal Control of Ice Crystallization in Supercooled Water via an Ultrashort Laser Impulse. Journal of Physical Chemistry Letters, 14(19), 4394-4402, 18 May 2023: © 2023 American Chemical Society. DOI: 10.1021/acs.jpclett.3c00414.Focused irradiation with ultrashort laser pulses realized the fine spatiotemporal control of ice crystallization in supercooled water. An effective multiphoton excitation at the laser focus generated shockwaves and bubbles, which acted as an impulse for inducing ice crystal nucleation. The impulse that was localized close to the laser focus and accompanied by a small temperature elevation allowed the precise position control of ice crystallization and its observation with spatiotemporal resolution of micrometers and microseconds using a microscope. To verify the versatility of this laser method, we also applied it using various aqueous systems (e.g., plant extracts). The systematic study of crystallization probability revealed that laser-induced cavitation bubbles play a crucial role in inducing ice crystal nucleation. This method can be used as a tool for studying ice crystallization dynamics in various natural and biological phenomena
Phase Ib/II study of nivolumab combined with palliative radiation therapy for bone metastasis in patients with HER2-negative metastatic breast cancer
Radiation therapy (RT) can enhance the abscopal effect of immune checkpoint blockade. This phase I/II study investigated the efficacy and safety of nivolumab plus RT in HER2-negative metastatic breast cancer requiring palliative RT for bone metastases. Cohort A included luminal-like disease, and cohort B included both luminal-like and triple-negative disease refractory to standard systemic therapy. Patients received 8 Gy single fraction RT for bone metastasis on day 0. Nivolumab was administered on day 1 for each 14-day cycle. In cohort A, endocrine therapy was administered. The primary endpoint was the objective response rate (ORR) of the unirradiated lesions. Cohorts A and B consisted of 18 and 10 patients, respectively. The ORR was 11% (90% CI 4–29%) in cohort A and 0% in cohort B. Disease control rates were 39% (90% CI 23–58%) and 0%. Median progression-free survival was 4.1 months (95% CI 2.1–6.1 months) and 2.0 months (95% CI 1.2–3.7 months). One patient in cohort B experienced a grade 3 adverse event. Palliative RT combined with nivolumab was safe and showed modest anti-tumor activity in cohort A. Further investigations to enhance the anti-tumor effect of endocrine therapy combined with RT plus immune checkpoint blockade are warranted
Measurement of low-energy antiproton detection efficiency in BESS below 1 GeV
An accelerator experiment was performed using a low-energy antiproton beam to
measure antiproton detection efficiency of BESS, a balloon-borne spectrometer
with a superconducting solenoid. Measured efficiencies showed good agreement
with calculated ones derived from the BESS Monte Carlo simulation based on
GEANT/GHEISHA. With detailed verification of the BESS simulation, the relative
systematic error of detection efficiency derived from the BESS simulation has
been determined to be 5%, compared with the previous estimation of
15% which was the dominant uncertainty for measurements of cosmic-ray
antiproton flux.Comment: 13 pages, 7 figure
In-hospital extracorporeal cardiopulmonary resuscitation for patients with out-of-hospital cardiac arrest: an analysis by time-dependent propensity score matching using a nationwide database in Japan
院外心停止患者における膜型人工肺を活用した蘇生 --膜型人工肺を活用した蘇生と生存率向上との関連--. 京都大学プレスリリース. 2023-11-21.BACKGROUND: Extracorporeal cardiopulmonary resuscitation (ECPR) has been proposed as a rescue therapy for patients with refractory cardiac arrest. This study aimed to evaluate the association between ECPR and clinical outcomes among patients with out-of-hospital cardiac arrest (OHCA) using risk-set matching with a time-dependent propensity score. METHODS: This was a secondary analysis of the JAAM-OHCA registry data, a nationwide multicenter prospective study of patients with OHCA, from June 2014 and December 2019, that included adults (≥ 18 years) with OHCA. Initial cardiac rhythm was classified as shockable and non-shockable. Patients who received ECPR were sequentially matched with the control, within the same time (minutes) based on time-dependent propensity scores calculated from potential confounders. The odds ratios with 95% confidence intervals (CI) for 30-day survival and 30-day favorable neurological outcomes were estimated for ECPR cases using a conditional logistic model. RESULTS: Of 57, 754 patients in the JAAM-OHCA registry, we selected 1826 patients with an initial shockable rhythm (treated with ECPR, n = 913 and control, n = 913) and a cohort of 740 patients with an initial non-shockable rhythm (treated with ECPR, n = 370 and control, n = 370). In these matched cohorts, the odds ratio for 30-day survival in the ECPR group was 1.76 [95%CI 1.38-2.25] for shockable rhythm and 5.37 [95%CI 2.53-11.43] for non-shockable rhythm, compared to controls. For favorable neurological outcomes, the odds ratio in the ECPR group was 1.11 [95%CI 0.82-1.49] for shockable rhythm and 4.25 [95%CI 1.43-12.63] for non-shockable rhythm, compared to controls. CONCLUSION: ECPR was associated with increased 30-day survival in patients with OHCA with initial shockable and even non-shockable rhythms. Further research is warranted to investigate the reproducibility of the results and who is the best candidate for ECPR
Superheavy element nuclear chemistry at RIKEN
金沢大学理工研究域物質化学系A gas-jet transport system has been coupled to the RIKEN gas-filled recoil ion separator GARIS to startup superheavy element (SHE) chemistry at RIKEN. The performance of the system was appraised using an isotope of element 104, 261Rf, produced in the 248Cm(18O,5n) 261Rf reaction. Alpha-particles of 261Rf separated with GARIS and extracted to a chemistry laboratory were successfully identified with a rotating wheel apparatus for α spectrometry. The setting parameters such as the magnetic field of the separator and the gas-jet conditions were optimized. The present results suggest that the GARIS/gas-jet system is a promising approach for exploring new frontiers in SHE chemistry: (i) the background radioactivities of unwanted reaction products are strongly suppressed, (ii) the intense beam is absent in the gas-jet chamber and hence high gas-jet efficiency is achieved, and (iii) the beam-free condition also allows for investigations of new chemical systems. © 2010 American Institute of Physics
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