Influence of a home-based exercise program on the urine pH in elderly female subjects: a secondary analysis of a randomized controlled trial

Background

A low urine pH is a characteristic metabolic feature of metabolic syndrome and type 2 diabetes. The purpose of the current study was to investigate the effects of a 12-week home-based bench step exercise on the urine pH status of elderly female subjects.

Methods

The current study is a secondary analysis of a randomized controlled trial (RCT) in which 59 postmenopausal female subjects were randomized to either the exercise group (n?=?29) or the control group (n?=?30). The subjects in the exercise group were instructed to perform home-based exercises using a bench step at the anaerobic threshold (AT), with a goal of performing ≥140 min/week at home for 12 weeks. The subjects in the control group were instructed to not change their normal lifestyle. Urine was collected after overnight fasting, and the urine pH was measured using a urinary test strip. The inter-group-differences at baseline and the pre-post changes within groups were assessed using the Mann-Whitney U test and Wilcoxon’s signed-rank test, respectively. Additionally, the difference in the post-intervention urine pH levels of the two groups, adjusted for the pre-intervention values (the estimated effect size) and the precision (95% confidence intervals) were investigated using an analysis of covariance.

Results

The pre-post comparison of the urine pH data using Wilcoxon’s signed-rank test showed a significant increase in the urine pH levels of the exercise group (p?<?0.05); there was no significant change in the urine pH levels of the control group. However, the estimated effect size (0.15) was small and the confidence interval straddled 0 (?0.25–0.55).

Conclusions

Based on the results of the current secondary analysis of an RCT, we could not clearly conclude that exercise has a beneficial effect on the urine pH. Further well-designed RCTs should be conducted to determine whether aerobic exercise is truly able to ameliorate urine acidification.

Trial registration

The study was retrospectively registered in the University Hospital Medical Information Network (UMIN) as “Effect of step exercise on aerobic fitness and progression of atherosclerosis in the elderly” under the registration number UMIN 000026743 (the date of registration: March 28, 2017).

     

Influence in covariance structure analysis: with an application to confirmatory factor analysis

Influence functions are derived for the parameters in covariance structure analysis, where the parameters are estimated by minimizing a discrepancy function between the assumed covariance matrix and the sample covariance matrix. The case of confirmatory factor analysis is studied precisely with a numerical example. Comparing with a general procedure called one-step estimation, the proposed procedure has two advantages:1) computing cost is cheaper, 2) the property that arbitrary influence can be decomposed into a fi-nite number of components discussed by Tanaka and Castano-Tostado(1990) can be used for efficient computing and the characterization of a covariance structure model from the sensitivity perspective. A numerical comparison is made among the confirmatory factor analysis and some procedures of ex-ploratory factor analysis by using the decomposition mentioned above.     

On the distribution of quadratic functionals of the ordinary and fractional Brownian motions

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Who Gets an Early Education? Family Income and the Enrollment of Three‐ to Five‐Year‐Olds from 1968 to 2000*

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Oligarchy for Social Choice Correspondences and Strategy-Proofness

We study the existence of a group of individuals which has some decisive power for social choice correspondences that satisfy a monotonicity property which we call modified monotonicity. And we examine the relation between modified monotonicity and strategy-proofness of social choice correspondences according to the definition by Duggan and Schwartz (2000). We will show mainly the following two results. (1) Modified monotonicity implies the existence of an oligarchy. An oligarchy is a group of individuals such that it has some decisive power (semi-decisiveness), and at least one of the most preferred alternatives of every its member is always chosen by any social choice correspondence. (2) Strategy-proofness of social choice correspondences is equivalent to modified monotonicity.     

Positive Feedback Model for City Vitalization

Abstract  In the present study, we first attempt to construct a model for the dynamics of city images, in which intra- and intercity communications promote the joint possession of city images by residents and the establishment of a city identity. It is suggested that community spirit, which emerges strongly associated with city identity, urges citizens to voluntarily take part in a city's cultural events. The voluntary participation of citizens may change various aspects of a city's functions and physical structure, and as a result the city becomes vitalized in a bottom-up way. Based on this model, we propose a new planning method to facilitate city vitalization as a substitute for hardware-oriented planning. Finally, to ascertain the effectiveness of the new planning method, we focus on Iida City, which has recently successfully established its identity as a puppet drama town.     

Quadratic perturbation expansions of certain functions of eigenvalues and eigenvectors and their application to sensitivity analysis in multivariate methods

Tanaka (1988) lias derived the influence functions, which are equivalent to the perturbation expansions up to linear terms, of two functions of eigenvalues and eigenvectors of a real symmetric matrix, and applied them to principal component analysis. The present paper deals with the perturbation expansions up to quadratic terms of the same functions and discusses their application to sensitivity analysis in multivariate methods, in particular, principal component analysis and principal factor analysis. Numerical examples are given to show how the approximation improves with the quadratic terms.     

A possible discrepancy between the exposed and the whole population depending on range-size and trap-spacing in vole populations

Conclusion From a field study for the vole population (Clethrionomys rufocanus) in Hokkaido in the late summer of 1965, it has been proved that the range length may decrease from 25 to 18 m by the gross along with the rise from 20 to 100 in the density level per acre, and hence that an appreciable discrepancy, due to underestimation, may be produced in estimates of the exposed as compared to the whole population at an outbreaking density as high as 100 on a plan with trap-spacing 10 m. In consideration of this together with my preceding results, the strict terms that we may enough approximate the whole one by estimating the exposed seem likely to be that the ratio of range radius to trap spacing, supposing a range is circular, should be near 2 or more at either ordinary or outbreaking densities, to say in the concrete, that the trap spacing as close as 5 m or so in grid is desirable with this vole, perhaps with most other voles.     

Social norms, inequality and child labor

This paper theoretically analyzes a situation wherein adults’ decisions on child labor are affected not only by materialistic utility but also by a social norm against child labor. The adult thus faces a tradeoff; on the one hand, household income rises if she sends her child to work. On the other hand, the adult suffers disutility from violating the social norm in so doing. We also suppose that the extent of disutility falls as more other adults have their children work. We then explore how the total amount of child labor in an economy changes as adults’ labor efficiencies rise or become more unequal. Our analysis reveals that a more equal distribution or rises in adults’ labor efficiency help decrease child labor only under certain conditions.     

The Changing Roles of NGOs in Nepal: Promoting Emerging Rights-Holder Organizations for Inclusive Aid

This article examines the unique roles of NGOs with special attention to the changing socio-political contexts of NGOs in terms of their partnerships with Rights-Holder Organizations (RHOs), which claim the rights of particular groups of excluded population. It reviews an example of the NGO working with RHOs in Nepal. NGO relationships with RHOs are delicate and not always equitable due to their different backgrounds and expertise. NGOs, comprising mostly people who are not members of the rights-holding groups, use their expertise to work for others over fixed periods, whilst RHOs work for their own constituencies through movements. Until the 1990s, NGOs supported so-called ‘beneficiaries’ who were members of excluded groups whose rights were being denied. Today, RHOs are formed directly by excluded groups. Some NGOs are trying to change their role to become promoters for RHOs, whilst others remain as their proxies, which merely creates an extra layer between RHOs and donors. The article attempts to prove that building equitable relationships between NGOs and RHOs is possible if NGOs have professionalism, expertise in capacity development and a readiness to become more inclusive. Though there are still several challenges ahead, such efforts by NGOs make it possible to change funding flows for RHOs and contribute to inclusive aid.