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The purpose of this paper is to analyze the influence of curvature on the transport of low-density lipoprotein (LDL) through a curved artery and concentration boundary layer characteristics numerically.

By using a projection method based on the second-order central difference discretization, the authors solve the set of governing equations, which consists of Navier–Stokes, continuity and species transport. The effects of initial straight length, as well as the curvature and wall shear stress (WSS) on LDL transport in a curved artery are established in this paper.

The obtained numerical results imply that the LDL concentration boundary layer thickness decreases in the outer part of the curved artery and increases in the inner part for both with or without initial straight length. The effect of Reynolds number on the concentration distribution in a curved artery with initial straight length is more pronounced than that on a fully curved artery, although an opposite trend was seen for the curvature ratio. The maximum surface LDL concentration is related to the regions with minimum WSS in the inner part of the curved artery, which has more potential the formation of atherosclerosis.

The authors present a comprehensive concentration distribution of LDL in the concentration boundary layer of the curved artery. The authors also characterize and predict the influence of curvature on the formation and development of atherosclerosis within the arterial wall.

The Navier‐Stokes equation and the species continuity equation have been solved numerically in a boundary fitted coordinate system comprising the geometry of a single strand bare tundish. The solution of the species continuity equation predicts the time evolution of the concentration of a tracer at the outlet of the tundish. The numerical prediction of the tracer concentration has been made with nine different turbulence models and has been compared with the experimental observation for the tundish. It has been found that the prediction from the standard k‐ε model, the k‐ε Chen‐Kim (ck) and the standard k‐ε with Yap correction (k‐ε Yap), matches well with that of the experiment compared to the other turbulence models as far as gross quantities like the mean residence time and the ratio of mixed to dead volume are concerned. It has been found that the initial transient development of the tracer concentration is best predicted by the low Reynolds number Lam‐Bremhorst model (LB model) and then by the k‐ε RNG model, while these two models under predict the mean residence time as well as the ratio of mixed to dead volume. The Chen‐Kim low Reynolds number (CK low Re) model (with and without Yap correction) as well as the constant effective viscosity model over predict the mixing parameters, i.e. the mean residence time and the ratio of mixed to dead volume. Taking the solution of the k‐ε model as a starting guess for the large eddy simulation (LES), a solution for the LES could be arrived after adopting a local refinement of the cells twice so that the near wall y⁺ could be set lower than 1. Such a refined grid gave a time‐independent solution for the LES which was used to solve the species continuity equation. The LES solution slightly over predicted the mean residence time but could predict fairly well the mixed volume. However, the LES could not predict both the peaks in the tracer concentration like the k‐ε, RNG and the Lam‐Bremhorst model. An analysis of the tracer concentration on the bottom plane of the tundish could help to understand the presence of plug and mixed flow in it.

We compare two approaches to measuring inequity in the health distribution. The first is the concentration index. The second is the calculation of the inequality in an overall measure of individual well-being, capturing both the income and health dimensions. We introduce the concept of equivalent income as a measure of well-being that respects preferences with respect to the trade-off between income and health, but is not subjectively welfarist since it does not rely on the direct measurement of happiness. Using data from a representative survey in France, we show that equivalent incomes can be measured using a contingent valuation method. We present counterfactual simulations to illustrate the different perspectives of the approaches with respect to distributive justice.

The on‐line concentration and temperature measurement of solutions is of great interest as a means of quality production control in many industrial processes, such as in food service industry, pharmaceuticals industry, chemical industry and environmental engineering, especially for harmful solutions or solutions that cannot be reached by the operator. This paper seeks to address these issues.

A high resolution all‐fiber multi‐parameter sensor system has been studied theoretically and experimentally. The sensor system can be used for on‐line monitoring of concentration and temperature simultaneously and dynamically. A combined long period fiber grating (CLPG) is used as the sensor head based on its resonance wavelength shifts being almost linearly with concentration and temperature, and also based on that the two applied resonance peaks have different concentration‐wavelength coefficients and different temperature‐wavelength coefficients. Two wavelength‐matched fiber Bragg gratings (FBGs) are used to convert resonance peak wavelengths of the CLPG into corresponding intensities for interrogation.

When the concentration and the temperature all fluctuate dynamically during experiments, a concentration resolution of 0.03 g/L has been achieved in the range of 0∼200 g/L, and a temperature resolution of 0.02C has been realized in the range of −20∼60C.

On‐line monitoring of concentration and temperature for solutions is a means of quality production control in biological, chemical and other many industrial processes, such as in food service industry, pharmaceuticals industry, chemical industry, and also in environmental engineering, especially for harmful solutions or solutions that cannot be reached by the operator. Optical fiber sensors have numerous advantages over traditional sensors, such as immunity to electromagnetic interference, higher stability and sensitivity, more easiness of multiplex, being competent for application in harsh environments, “smart structures” and on‐site measurements. Long period optical fiber grating sensor is the most appropriate sensor for multi‐parameter monitoring in the fields mentioned above, which has all the advantages of optical fiber sensor. Besides, optical fiber grating sensors can be used for monitoring more accurately because its signal is coded by wavelength. The all‐fiber sensor system is suitable for remote monitoring of many solutions, such as the solutions of NaCl, glucose, alcohol, and hydrocarbon.

Financial protection of households against catastrophic healthcare expenditure (CHE) is defined as one of the main goals in health systems. The purpose of this paper is to measure and decompose socioeconomic inequality in CHE among households in Kermanshah province, Western of Iran.

This cross-sectional study was carried out among 1,188 households in 2017. Data were extracted from the Household Income and Expenditure Survey which is conducted by the Statistical Center of Iran. The CHE is defined as household healthcare expenditure greater than or equal to the 40 percent of household’s “capacity to pay.” The concentration curve and the Wagstaff (W) and Erreygers (E) indexes were used to illustrate and measure the extent of socioeconomic inequality in CHE. In addition, the authors decomposed the W and E indexes to identify the main determinants of socioeconomic inequality in CHE.

The results indicated that the prevalence of CHE among households was 4.12 percent (95% confidence interval (CI): 3.13 to 5.42 percent). The estimated value of the W and E indexes were −0.2849 (95% CI: −0.4493 to −0.1205) and −0.0451 (95% CI: −0.0712 to −0.0190), respectively; suggesting the concentration of CHE prevalence among the poor households. Decomposition analyses indicated socioeconomic status as the most important factor contributing to the concentration of CHE among the poor. In contrast, health insurance coverage was found to increase the concentration of CHE among the rich in Iran.

The current study demonstrated a higher concentration of CHE among the poor households in Kermanshah province. These results call for the government’s efforts to reduce healthcare expenditure among socioeconomically disadvantaged populations. Further studies are required to understand the mechanisms through which health insurance coverage increased the probability of CHE among rich in Kermanshah province.

The purpose of this paper is to study, inequalities between general physicians’ and specialists’ visits in Shiraz. Also, the factors effecting the utilization of visits were determined.

Concentration index and curves, ranked by income and quality of life were used to estimate the amount of inequality in the utilization of services. Health utilization data which had been gathered already were used for this purpose. Poisson regression was used to construct the models.

Results of the study showed that, inequalities in specialists’ visits were higher than GPs’. Complementary insurances users and females used more specialist services. People with higher quality of life utilized fewer GPs’ and specialists’ services.

New evidences about inequality in health services utilization and its components in Iran was surveyed.

The Internal Revenue Code of the U.S. as well as income tax statutes in a number of states contain provisions that penalize some married couples by virtue of their marital status. These families have greater tax liabilities than would apply if the husband and wife divorced. At the same time, other married couples benefit from reduced taxes made possible by the income splitting provisions of the laws. Thus, some families receive tax benefits and others are penalized as a consequence of the choice to be married. There is now much discussion in Washington and state capitals of reducing and possibly eliminating the so-called “marriage tax”. Most proposals for reform retain the income splitting provision of the tax code; thereby avoiding direct harm to families currently receiving tax benefits from marriage. This is the approach adopted in this paper.

The objective of this study was to evaluate the influence of Saccharomyces boulardii on the kinetics of fermentation for organic and conventional apple pulp and to verify the effect of the antioxidant quercetin on the response to cellular oxidative stress.

The kinetic parameters, the content of phenolic compounds, the quantity of quercetin and the antioxidant activity were determined during the fermentation process. The effect of quercetin on cellular oxidative stress was also investigated.

The content of phenolic compounds, the antioxidant activity and the quercetin concentration were higher in the organic fermented apple pulp (ORG) than in the conventional fermented apple pulp (CON). However, both apple pulps were considered ideal substrates for the growth of S. boulardii, suggesting that they are potentially probiotic. After fermentation, the quercetin concentration in the ORG treatment and YPDQ treatment (YPD broth with 0.1 mg quercetin rhamnoside/mL) increased viability by 9%, while in the CON treatment generated there was an increase of 6% in viability, compared to the YPD control treatment (YPD broth).

The high concentration of quercetin in the organic apple pulp supports the proposal that quercetin reduces the oxidative stress mediated by reactive oxygen species through its antioxidant action on S. boulardii that have similarities to mammalian eukaryotic cells. These findings suggest that fermented organic apple pulp could be consumed as a potential non-dairy probiotic product.

Nearly 200m people in the world experience considerable functioning difficulties. Also, more than three-fourth of the population aged 50 years and over is suffering from some kind of disability in India, China, Ghana, Russia, Mexico and South Africa. Despite the compelling nature of this issue, evidence on socioeconomic disparity in the occurrence of disability is lacking throughout the world and particularly in the aforementioned countries. The purpose of this paper is twofold – first, to examine the socioeconomic inequalities in the prevalence of disability in the selected countries; and second, to investigate the cross-country differentials in the prevalence of disability by socioeconomic characteristics.

The authors use data from the Study on Global Ageing and Adult Health (SAGE) conducted in China, Ghana, India, Mexico, Russia and South Africa during 2007–2010. Disability scores have been constructed using Item Response Theory Partial Credit Model based on eight health and functioning domains. Bivariate analysis, concentration curves, concentration indices and multivariate regressions have been used in the analysis presented in this paper.

The authors find that the prevalence of disability varied considerably across sociodemographic groups. Moreover, this variation is not uniform across all countries. Also, age, Sex, work status, years of schooling and economic status emerged out as significant predictors of disability among the studied countries.

This is perhaps the first study which examines the socioeconomic inequality in disability conceptualized in a comprehensive manner among older adults spread across low to upper middle income countries. The alarming level of prevalence of disability among sociodemographic disadvantage groups calls for immediate attention in terms of detailed study of risk factors, effective policy and timely intervention.

The purpose of this paper is to examine the incidence of public education subsidies in Ghana. Since the late 1990s, Ghana’s government has increasingly recognized human capital as key to alleviating poverty and income inequality, causing dramatic increases of government expenditures to the education sector. At the same time user fees have been introduced in higher education while basic education is being made progressively free. The question then is, whether these spending increases have been effective in reaching the poor and to what extent? What factors influence the poor’s participation in the public school system?

The authors address the key issues by employing both the standard benefit incidence methods and the willingness-to-pay method.

The results give a clear evidence of progressivity with consistent ordering: pre-schooling and primary schooling are the most progressive, followed by secondary, and then tertiary. Own price and income elasticities are higher for private schools than public schools and for secondary than basic schools.

Given the liquidity constraints African governments face yet there is the need to improve the human capacity of the countries, this study offers solution to how to optimally allocate the educational budget.

The use of policy simulations to ascertain the incidence of public spending on education is innovative as far as previous studies in Africa is concerned.