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An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Abstract Background The combination of budesonide + formoterol (BFC) offers the advantages of dose adjustment in a single inhaler according to asthma symptoms. We analyzed the relationship between asthma symptoms in terms of peak expiratory flow (PEF) and dose adjustment by the patient. Methods Twenty-eight patients with asthma who used BFC for alleviation of their symptoms (12 men, 16 women; 60 years old) were instructed that the inhaled BFC dose could be increased to a maximum of 8 inhalations per day according to symptom severity. Patients measured and recorded PEF every morning and evening in their asthma diary along with their symptoms and the dose of drugs taken. Results Sixteen of the 28 patients increased their dose for asthma symptoms. The time to recovery from the asthma symptoms was significantly shorter when cough was the only symptom present compared with dyspnea or wheeze (1.4 vs. 5.3 or 6.6 days, p

In Japan, outcome measures for maternal and child health measures such as maternal, perinatal, and infant mortality have consistently shown a trend toward improvement. On the other hand, the problems of the declining birth rate, child abuse, and domestic violence have become evident since the 1990s. In terms of Japan's maternal and child health, it is necessary to take measures to preserve mental health of mothers and children, and also to respond to family issues such as abuse and violence. The services needed such as comprehensive support centers for families with children and new postpartum care programs have been established. It is necessary to further improve the competence of doctors, public health nurses, and midwives working in the maternal and child health field and to promptly construct a cooperation system in the community. J. Med. Invest. 69: 159-164, August, 2022. [ABSTRACT FROM AUTHOR]

This paper investigates and compares four commonly used flow transport equation-based cavitation models and their applicability to predict the cavitation performance of an industrial centrifugal pump with a helical inducer. The main purpose of this study is to identify, for this specific application, the most appropriate cavitation model and the associated empirical constants. Each cavitation model is reviewed in detail and the uniqueness of each model is outlined. Each cavitation model is incorporated in a computational fluid dynamics code to study the vaporization and condensation transport rate of the fluid. Experimental tests are conducted on a pump system to determine the true cavitation performance in terms of net positive suction head (NPSH). Experimental results are compared to simulation results for different cavitation models to validate cavitation performance predictions, along with the empirical constants. Lastly, bubble formation, cavitation inception, and bubble growth predicted by each cavitation model are compared with the experimental results. A sensitivity analysis is conducted in order to determine the impact of each set of empirical constants to the condensation and the vaporization rate in the centrifugal pump. Results show that two of the cavitation models exhibit high dependency on the empirical constants in terms of change in vaporization rate. Modifications to empirical constants for two of the four cavitation models are suggested to obtain agreement with the experimentally observed cavitation behavior and better predict NPSH performance for the industrial pump studied. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the inducer tip clearance is studied to understand its impact on the cavitating and noncavitating performance of centrifugal pumps. Helical inducers with constant pitch and with variable (progressive) pitch are considered. Computational fluid dynamics (CFD) simulations of a single stage pump are conducted on each inducer type to determine the cavitating (two-phase) and noncavitating (single-phase) performance for varying inducer tip clearance. The Rayleigh-Plesset cavitation model is used to understand the bubble dynamics under the assumptions of single fluid undergoing no thermal energy transfer between each phase. Experimental tests are conducted on a pump with the variable pitch inducer to determine the true performance in cavitating and noncavitating operating conditions. Experimental results are compared to the simulations to validate the accuracy of the proposed numerical modeling. Net positive suction head (NPSH) with 3% differential head drop is used as a criterion to identify the true cavitation performance of each inducer configuration. It is found that, as the inducer tip clearance increases, excessive back leakage and larger vortex recirculation occur at the tip location. This results in pressure loss within the inducer and, consequently, degrades the cavitation performance. In addition, the change in cavitation performance with the tip clearance is much more evident for variable pitch inducer geometries as compared to the constant pitch case. Furthermore, the impact on the noncavitating performance of inducer tip clearance is found to be minimal. [ABSTRACT FROM AUTHOR]

Whole-lung lavage (WLL) remains the standard therapy for pulmonary alveolar proteinosis (PAP), a process in which accumulated surfactants are washed out of the lung with 0.5-2.0 l of saline aliquots for 10 -30 wash cycles. The method has been established empirically. In contrast, the kinetics of protein transfer into the lavage fluid has not been fully evaluated either theoretically or practically. Seventeen lungs from patients with autoimmune PAP underwent WLL. We made accurate timetables for each stage of WLL, namely, instilling, retaining, draining, and preparing. Subsequently, we measured the volumes of both instilled saline and drained lavage fluid, as well as the concentrations of proteins in the drained lavage fluid. We also proposed a mathematical model of protein transfer into the lavage fluid in which time is a single variable as the protein moves in response to the simple diffusion. The measured concentrations of IgG, transferrin, albumin, and β2-microglobulin closely matched the corresponding theoretical values calculated through differential equations. Coefficients for transfer of β2-microglobulin from the blood to the lavage fluid were two orders of magnitude higher than those of IgG, transferrin, and albumin. Simulations using the mathematical model showed that the cumulative amount of eliminated protein was not affected by the duration of each cycle but dependent mostly on the total time of lavage and partially on the volume instilled. Although physicians have paid little attention to the transfer of substances from the lung to lavage fluid, WLL seems to be a procedure that follows a diffusion-based mathematical model. [ABSTRACT FROM AUTHOR]