Stress intensity factor solution for edge interface crack based on the crack tip stress without the crack

In this paper, a new solution is discussed for the stress intensity factor of an edge interface crack. The intensity of the singular stress field (ISSF) at the interface end before appearing the edge interface crack is distinguished from the stress intensity factor (SIF) of the interface crack itself. By considering those two distinct double singular stress fields, the ISSF and the SIF are discussed under arbitrary material combinations. By focusing on the crack tip stress without the interface crack σy(a), the SIF of the edge interface crack can be expressed conveniently. This is because the crack tip stress without the interface crack is reflecting the ISSF at the interface end. The SIFs based on the crack tip stress without the interface crack are indicated by varying the crack length and material combination. It is found that the normalized SIFs (F1,int and F2,int) based on σy(a) are independent of the geometrical condition for the wide range of the crack length

Uranium–Lead Systematics of Lunar Basaltic Meteorite Northwest Africa 2977

Northwest Africa (NWA) 2977 is a lunar basaltic meteorite that was found in 2005 and has been classified as an olivine cumulate gabbro. This meteorite contains a shock melt vein (SMV) induced by an intense shock event. We report herein on an in-situ analysis of phosphates in the host gabbro and the shock vein for the U–Pb dating of NWA 2977 using an ion microprobe, NanoSIMS. The majority of the analyzed phosphates, in both the SMV and host-rock, lie on a linear regression in 238U/206Pb–207Pb/206Pb–204Pb/206Pb three-dimensional space, indicating a total Pb/U isochron age of 3.15±0.12 Ga (95% confidence level), which is consistent ages determined in previous isotopic studies of NWA 2977 (Sm–Nd age of 3.10±0.05 Ga, Rb–Sr age of 3.29±0.11 Ga, and Pb–Pb baddeleyite age of 3.12±0.01 Ga), and identical to the age of the U–Pb phosphate in a paired meteorite NWA 773, 3.09±0.20 Ga, derived from our dataset. There was no clear difference in the formation age between the phosphates found in the SMV and host-rock, although the shape and size of the grains and the Raman spectra show the evidence of intense shock metamorphism. Based on these findings, the cooling rate of the phosphate was very rapid, constrained to be larger than 140 K/s

ホログラフィックデータストレージにおけるフィルタ設計及び変調符号の構成に関する研究

東京理科大学201

Numerical Model of Radical Photopolymerization Based on Interdiffusion

An accurate reaction model is required to analyze the characteristics of photopolymers. For this purpose, we propose a numerical model for radical photopolymerization. In the proposed model, elementary reactions such as initiation, propagation, and termination are considered, and we assume interdiffusion for each component in the material. We analyzed the diffraction characteristics of a radical photopolymer based on the proposed interdiffusion model with the beam propagation method. Moreover, we also performed hologram-recording experiments and evaluated the diffraction characteristics of the photopolymer medium. By comparing the numerical and experimental results, medium parameters such as reaction rate and diffusion coefficient can be estimated. We confirmed that the interdiffusion model can reproduce the experimental results and showed that the medium parameters affect the diffraction characteristics

Efficacy of nasal high flow therapy on the coordination between breathing and swallowing of saliva during daytime nap in chronic obstructive pulmonary disease patients

BACKGROUND: There are some clinical reports on dysphagia in patients with chronic obstructive pulmonary disease(COPD);however, its pathophysiology remains largely unknown.Changes in respiratory function occur in patients with COPD causing a decrease in tidal volume and an increase in respiratory rate (tachypnea). In addition, it leads to lack of coordination between respiration and swallowing.A new treatment called nasal high flow (NHF) has been introduced for patients with COPD, replacing the traditional non-invasive ventilation (NIV) procedure. The NHF therapy involves inhalation of high flow of humidified air, which reduces respiratory effort in patients with COPD. Furthermore,NHF therapy facilitates swallowing of saliva even during respiratory management. A recent clinical study reported that high-flow nasal cannula oxygen therapy for 6 weeks improved the health-related quality of life and reduced hypercapnia in patients with stable COPD. Taken together, NHF therapy is gaining attention in the clinical management of patients with COPD.Therefore, in this study, we aim to examine the efficacy of NHF therapy on the coordination between breathing and swallowing of saliva during daytime nap in patients with COPD. METHODS/DESIGN: This open-label,investigator-initiated, single center study will evaluate the efficacy of NHF therapy on the coordination between breathing and swallowing of saliva during the daytime nap in COPD patients with forced expiratory volume in 1?second (FEV1%) of <70% during treatment at the Nagasaki University Hospital Respiratory Rehabilitation Center. Evaluations will be performed during the 90 to 180?minute "daytime nap" in the measurement room of the hospital.The primary endpoint will be the rate of appearance of the expiratory phase after swallowing of saliva and the frequency of swallowing during the measurement period. DISCUSSION: The purpose of this study is to obtain evidence regarding the utility of NHF as a potential therapeutic device for COPD patients to prevent aspiration of saliva during the sleep stage of daytime nap. The utility will be assessed by comparing the decrease in incidence rates of the expiratory phase after swallowing of saliva in the NHF device group and the control group, wherein this device was not used