A simplified approach to estimating the distribution of occasionally-consumed dietary components, applied to alcohol intake

BACKGROUND: Within-person variation in dietary records can lead to biased estimates of the distribution of food intake. Quantile estimation is especially relevant in the case of skewed distributions and in the estimation of under- or over-consumption. The analysis of the intake distributions of occasionally-consumed foods presents further challenges due to the high frequency of zero records. Two-part mixed-effects models account for excess-zeros, daily variation and correlation arising from repeated individual dietary records. In practice, the application of the two-part model with random effects involves Monte Carlo (MC) simulations. However, these can be time-consuming and the precision of MC estimates depends on the size of the simulated data which can hinder reproducibility of results. METHODS: We propose a new approach based on numerical integration as an alternative to MC simulations to estimate the distribution of occasionally-consumed foods in sub-populations. The proposed approach and MC methods are compared by analysing the alcohol intake distribution in a sub-population of individuals at risk of developing metabolic syndrome. RESULTS: The rate of convergence of the results of MC simulations to the results of our proposed method is model-specific, depends on the number of draws from the target distribution, and is relatively slower at the tails of the distribution. Our data analyses also show that model misspecification can lead to incorrect model parameter estimates. For example, under the wrong model assumption of zero correlation between the components, one of the predictors turned out as non-significant at 5 % significance level (p-value 0.062) but it was estimated as significant in the correctly specified model (p-value 0.016). CONCLUSIONS: The proposed approach for the analysis of the intake distributions of occasionally-consumed foods provides a quicker and more precise alternative to MC simulation methods, particularly in the estimation of under- or over-consumption. The method is readily available to non-technical users in contrast to MC methods whereby the simulation error may be substantial and difficult to evaluate

A study of the characteristics of food import dependence of the countries

The causes of import dependence in different countries are studied in the article. It is shown that food import dependence is in one degree or another inherent in many countries, including the developed ones, which are food products exporters at the same time. It is revealed that the import dependence of countries with high and low GDP per capita, the value added level in agriculture and the availability of land resources differ significantly. Based on the results obtained, it is concluded that countries with a high level of GDP per capita, a high added value level in agriculture and high availability of agricultural land resources are import-dependent, as a rule, for certain groups of food products. Countries with low GDP per capita, a low value-added level in agriculture and low availability of agricultural land resources import all or many of the staples

Brand Marketing Trends in Russian Social Media

In the paper, the authors have reviewed common actions, an aim of which is consumer engagement in interactions with a brand in social media. They have also reviewed engagement types and effects of their use. Based on a literature review, in a clearer way, the authors have presented attributes of Internet marketing and explored brand-marketing challenges on the Internet. Authors have summarized the information on Russian users' efforts in social media. Based on empirical data, the researchers have made a portrait of media actors and the audience in Russian social media, identified target groups among consumers by a number of criteria. They have also completed an analysis of common ways for promotion of companies (brands) and their products and services, taking into account a structure of social media users and specifics of communication channels. Findings include identified most common lines of business for promotion in a competitive social media based on efficiency of the engagement response (rate) per brand/product-specific page or post. These data have made it possible to formalize strategic goals and possible results of brand marketing for various types of social media

Reconstruction of history of the Tatar Arch in the Neogene-Quaternary time by means of the morphometric analysis

The history of neotectonic development of the Tatar Arch is reconstructed according to the morphometric analysis data. High degree of neotectonic activity of the Southern Dome of the Tatar Arch is shown. Connections between the Tatar Arch morphostructure and its deep structure are traced. The research shows that the majority of local structures (of the second and third order) within the arch are recent formations aged by not more than 106 years old

Evaluation of optoelectronic channel leak speech with the use of mathematical models

In this article we analyzed optoelectronic channel leakage of voice information. It’s a method for processing the measurement signal, including an assessment of the cumulative effect of amplitude and phase modulation. Acoustic vibrations of the solid medium, subject to amplitude and phase modulation, presents a model of a rectangular vibrating membrane. The method of estimating the signal/noise ratio by using the mathematical model developed security assessment. During the research density distribution phase at various energy indicators was built showing the degree of dependence of the phase of the resulting fluctuations of the original signal

Evaluation of optoelectronic channel leak speech with the use of mathematical models

In this article we analyzed optoelectronic channel leakage of voice information. It’s a method for processing the measurement signal, including an assessment of the cumulative effect of amplitude and phase modulation. Acoustic vibrations of the solid medium, subject to amplitude and phase modulation, presents a model of a rectangular vibrating membrane. The method of estimating the signal/noise ratio by using the mathematical model developed security assessment. During the research density distribution phase at various energy indicators was built showing the degree of dependence of the phase of the resulting fluctuations of the original signal

Analysis of acoustic-optic-fibre channel leakage in fibre-optic communication lines

The paper considers the model of fibre-optic communication lines. The experiment has shown the greatest influence of acoustic signal on the optical signal in the optical fibre passes. Physical principles of formation of leakage channels in fibre cable are described. Modulation types peculiar to the optical signal under the influence of an external acoustic source are listed

Analysis of acoustic-optic-fibre channel leakage in fibre-optic communication lines

The paper considers the model of fibre-optic communication lines. The experiment has shown the greatest influence of acoustic signal on the optical signal in the optical fibre passes. Physical principles of formation of leakage channels in fibre cable are described. Modulation types peculiar to the optical signal under the influence of an external acoustic source are listed