235 research outputs found
反復的な督励が口頭指導下の心肺蘇生法に与える効果に関する無作為化シミュレーション研究
Background: Current guidelines emphasize the assistance of the emergency dispatcher in bystander cardiopulmonary resusitation (CPR). Its quality, however, has varied across cases. Objective: To determine the effect of repetitive coaching by dispatchers using verbal encouragement on the quality of lay-rescuer CPR. Methods: We conducted a dispatch-assisted CPR (DACPR) simulation study. Participants with no CPR training within the previous year were assigned randomly to 1 of 2 DACPR simulations. One was the No Coaching Group: callers were told to perform CPR and the dispatcher periodically confirmed that the caller was performing CPR. The second group was the Coaching Group: the dispatcher repetitively coached, encouraged, and counted aloud using a metronome. Participants performed CPR for 2 min under instruction from the study dispatcher. Parameters including chest compression depth, rate, and chest compression fraction were recorded by video camera and CPR manikin. Results: Forty-nine participants 20 to 50 years of age were recruited, and 48 completed the simulation (Coaching Group, n = 27; No Coaching Group, n = 21). The chest compression fraction was higher in the Coaching Group (99.4% vs. 93.0%, p = 0.005) and no participants interrupted chest compression more than 10 s in this group. When comparing the average depth of each 30-s period in each group, the depth increased over time in the Coaching Group (40.9 mm, 43.9 mm, 44.1 mm, and 42.8 mm), while it slightly decreased in the No Coaching Group (40.6 mm, 40.1 mm, 39.4 mm, and 39.8 mm). Conclusions: Repetitive verbal encouragements augmented chest compression depth with less-hands off time. Continuous coaching by dispatchers can optimize lay-rescuer CPR.博士(医学)・甲第852号・令和4年9月28日© 2022 Elsevier Inc.© 2022 The Author(s). Published by Elsevier Inc.This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
Implementation of a modified Nesterov's Accelerated quasi-Newton Method on Tensorflow
Recent studies incorporate Nesterov's accelerated gradient method for the
acceleration of gradient based training. The Nesterov's Accelerated
Quasi-Newton (NAQ) method has shown to drastically improve the convergence
speed compared to the conventional quasi-Newton method. This paper implements
NAQ for non-convex optimization on Tensorflow. Two modifications have been
proposed to the original NAQ algorithm to ensure global convergence and
eliminate linesearch. The performance of the proposed algorithm - mNAQ is
evaluated on standard non-convex function approximation benchmark problems and
microwave circuit modelling problems. The results show that the improved
algorithm converges better and faster compared to first order optimizers such
as AdaGrad, RMSProp, Adam, and the second order methods such as the
quasi-Newton method.Comment: Paper published in 2018 17th IEEE International Conference on Machine
Learning and Applications (ICMLA
Analyzing the Development of a Remote Debate Program Using Video Annotation through a Systems Approach
This study aims to apply a systems approach to analyze the development of an education system for remote asynchronous debates. Although several studies have applied a systems approach to various objects, they attempted to improve projects using the approach by intention. However, in our study, the use of a systems approach was an unintentional part of the process, with stakeholders not being explicitly aware of the concepts behind systems thinking. In the midst of the process, a variety of systems thinking methods were partially adopted, making the project more systemic; however, the project was not oriented to follow specific problem-solving techniques. An educational program and information system for education support with sufficient systemic properties was created with such a systems approach. We propose that working on a problem with significant underlying systemic properties may help one to naturally adopt a systems approach
A Stochastic Variance Reduced Nesterov's Accelerated Quasi-Newton Method
Recently algorithms incorporating second order curvature information have
become popular in training neural networks. The Nesterov's Accelerated
Quasi-Newton (NAQ) method has shown to effectively accelerate the BFGS
quasi-Newton method by incorporating the momentum term and Nesterov's
accelerated gradient vector. A stochastic version of NAQ method was proposed
for training of large-scale problems. However, this method incurs high
stochastic variance noise. This paper proposes a stochastic variance reduced
Nesterov's Accelerated Quasi-Newton method in full (SVR-NAQ) and limited
(SVRLNAQ) memory forms. The performance of the proposed method is evaluated in
Tensorflow on four benchmark problems - two regression and two classification
problems respectively. The results show improved performance compared to
conventional methods.Comment: Accepted in ICMLA 201
交通外傷における救急隊の現場滞在時間に関連する要因とその地域差についての検討
Background: The outcome of road traffic injury (RTI) is determined by duration of prehospital time, patient’s demographics,
and the type of injury and its mechanism. During the emergency medical service (EMS) prehospital time
interval, on-scene time should be minimized for early treatment. This study aimed to examine the factors influencing
on-scene EMS time among RTI patients.
Methods: We evaluated 19,141 cases of traffic trauma recorded between April 2014 and March 2020 in the EMS
database of the Nara Wide Area Fire Department and the prehospital database of the emergency Medical Alliance
for Total Coordination of Healthcare (e-MATCH). To examine the association of the number of EMS phone calls until
hospital acceptance, age ≥65 years, high-risk injury, vital signs, holiday, and nighttime (0:00–8:00) with on-scene time,
a generalized linear mixed model with random effects for four study regions was conducted.
Results: EMS phone calls were the biggest factor, accounting for 5.69 minutes per call, and high-risk injury
accounted for an additional 2.78 minutes. Holiday, nighttime, and age ≥65 years were also associated with increased
on-scene time, but there were no significant vital sign variables for on-scene time, except for the level of consciousness.
Regional differences were also noted based on random effects, with a maximum difference of 2 minutes among
regions.
Conclusions: The number of EMS phone calls until hospital acceptance was the most significant influencing factor
in reducing on-scene time, and high-risk injury accounted for up to an additional 2.78 minutes. Considering these factors,
including regional differences, can help improve the regional EMS policies and outcomes of RTI patients.博士(医学)・甲第880号・令和5年3月15
外側環軸関節の関節症性変化のリスク増加に関連する要因; 後ろ向き研究
Purpose Atlantodens osteoarthritis and atlantoaxial osteoarthritis cause neck pain and suboccipital headaches. Currently,
knowledge on the risk factors for atlantoaxial osteoarthritis is lacking. This study aimed to investigate the factors related
to the increased risk of atlantoaxial osteoarthritis. Methods We analyzed computed tomography (CT) images of the upper
cervical spine of 1266 adult trauma patients for whom upper cervical spine CT was performed at our hospital between 2014
and 2019. The degree of atlantoaxial osteoarthritis was quantified as none-to-mild (not having osteoarthritis) or moderateto-
severe (having osteoarthritis). Risk factors associated with atlantoaxial osteoarthritis were identified using univariate and
multivariable logistic regression analyses. Results The study group included 69.4% men, and the overall average age of the
study population was 54.9 ± 20.4 years. The following factors were independently and significantly associated with atlantoaxial
osteoarthritis in the multivariable logistic regression analysis: age in the sixth decade or older (odds ratio [OR], 20.5;
95% confidence interval [CI], 6.2‒67.2, p < 0.001), having calcific synovitis (OR, 4.9; 95% CI, 2.4‒9.9, p < 0.001), women
sex (OR, 3.3; 95% CI, 1.9‒5.7, p = 0.002), and not having atlantodens osteoarthritis (OR, 2.1; 95% CI, 1.2‒3.8, p = 0.014).
Conclusion In the multivariable logistic regression analysis, age in the sixth decade or older, calcification of the transverse
ligament, being women, and not having atlantodens osteoarthritis were found to be significantly associated with atlantoaxial
osteoarthritis. Delayed diagnosis and treatment can be avoided by focusing on these risk factors.博士(医学)・甲第873号・令和5年3月15
Coupled-Cluster Approach to Electron Correlations in the Two-Dimensional Hubbard Model
We have studied electron correlations in the doped two-dimensional (2D)
Hubbard model by using the coupled-cluster method (CCM) to investigate whether
or not the method can be applied to correct the independent particle
approximations actually used in ab-initio band calculations. The double
excitation version of the CCM, implemented using the approximate coupled pair
(ACP) method, account for most of the correlation energies of the 2D Hubbard
model in the weak () and the intermediate regions (). The error is always less than 1% there. The ACP approximation gets
less accurate for large () and/or near half-filling.
Further incorporation of electron correlation effects is necessary in this
region. The accuracy does not depend on the system size and the gap between the
lowest unoccupied level and the highest occupied level due to the finite size
effect. Hence, the CCM may be favorably applied to ab-initio band calculations
on metals as well as semiconductors and insulators.Comment: RevTeX3.0, 4 pages, 4 figure
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