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The relaxation spectra, from which other material functions used to describe mechanical properties of materials can be uniquely determined, are important for modeling the rheological properties of polymers used in chemistry, food technology, medicine, cosmetics, and many other industries. The spectrum, being not directly accessible by measurement, is recovered from relaxation stress or oscillatory shear data. Only a few models and identification methods take into account the non-negativity of the real spectra. In this paper, the problem of recovery of non-negative definite relaxation spectra from discrete-time noise-corrupted measurements of relaxation modulus obtained in the stress relaxation test is considered. A new hierarchical identification scheme is developed, being applicable both for relaxation time and frequency spectra. Finite-dimensional parametric classes of models are assumed for the relaxation spectra, described by a finite series of power-exponential and square-exponential basis functions. The related models of relaxation modulus are given by compact analytical formula, described by the products of power of time and the modified Bessel functions of the second kind for the time spectrum, and by recurrence formulas based on products of power of time and complementary error functions for frequency spectrum. The basis functions are non-negative. In result, the identification task was reduced to a finite-dimensional linear-quadratic problem with non-negative unknown model parameters. To stabilize the solution, an additional smoothing constraint is introduced. Dual approach was used to solve the stated optimal identification task resulting in the hierarchical two-stage identification scheme. In the first stage, dual problem is solved in two levels and the vector of non-negative model parameters is computed to provide the best fit of the relaxation modulus to experiment data. Next, in second stage, the optimal non-negative spectrum model is determined. A complete scheme of the hierarchical computations is outlined; it can be easily implemented in available computing environments. The model smoothness is analytically studied, and the applicability ranges are numerically examined. The numerical studies have proved that using developed models and algorithm, it is possible to determine non-negative definite unimodal and bimodal relaxation spectra for a wide class of polymers. However, the examples also demonstrated that if the basis functions are non-negative and the model is properly selected for a given type of the real spectrum (unimodal, multimodal), the optimal model determined without non-negativity constraint can be non-negative in the dominant range of its arguments, especially in the wide neighborhood of the spectrum peaks.

Background: Pregnancy is one of the few periods in a woman's life when extra weight is not perceived as a negative factor, but has positive connotations with healthy fetal development, which runs against the modern cult of a perfect, slim and healthy body. Most research studies focus on excessive rather than insufficient weight gain in successive trimesters of pregnancy., Objective: The aim of this study was to evaluate women's knowledge about the influence of diet on pregnancy outcome and to assess changes in body weight and eating behaviors during pregnancy., Materials and Methods: The study consisted of an online survey. A total of 325 correctly and completely filled in questionnaires were considered. The respondents were divided into two groups: women without children (44.92%) and pregnant women and mothers (55.08%). The respondents' knowledge about eating behaviors during pregnancy was compared between the two groups. The responses given by mothers were used to evaluate weight gains during pregnancy and the nutritional status of pregnant women., Results: Changes in body weight during pregnancy were regarded as acceptable and pregnancy weight gain was considered a normal process by 92% of the respondents. Pregnant women had greater knowledge about the need for increased caloric intake in successive trimesters (p=0.0012). The respondents' knowledge about maternal health and healthy fetal development was assessed with the use of 10 true or false questions. The average score was 6.3±1.8 points, and no significant differences were found between mothers/pregnant women and women without children (6.6±1.3 vs 6.2±1.7, p>0.05). In the present study, 67% of the respondents were of the opinion that they followed a healthy diet, 14% claimed that they did not eat right, but were not motivated to make any changes., Conclusions: The respondents were aware that weight gain during pregnancy is a normal physiological process, but 1/3 of the respondents did not feel comfortable with the observed changes. The respondents did not have sufficient knowledge about the influence of maternal weight on fetal development. The use of diuretics and laxatives by pregnant women without medical consultation is a worrying phenomenon. These results indicate that women should have better access to knowledge about the impact of healthy nutrition on pregnancy outcome., Competing Interests: The authors declare no conflict of interest, (© Copyright by the National Institute of Public Health NIH - National Research Institute.)

Purpose: The balance, known as the ability to independently maintain the body in a certain position and return to the starting position, can be divided into static and dynamic balances. Social Latin American dances (salsa, bachata) require dancers to do a characteristic figure, however, they are not trained as intensively as dancing sports. The aim of the study was to assess the static and dynamic balances of dancers, who are regularly dancing those selected Latin American dances, by comparison with those who do not., Methods: The study was conducted among 34 dancers from a Krakow Dancing School and, 37 students of the Jagiellonian University, aged 21-35. A SIGMA balance platform was used to measure static and, the Y-Balance Test platform to assess dynamic balance. The Student's T-test, Mann- Whitney U-test and Spearman's rank correlation coefficient were used in statistical analysis., Results: There were neither significant differences between right and left lower limbs of dancers, nor between values of tilts on the YBT platform in both investigated groups. Non-dancers, however, showed a slightly higher positive correlation between the deviations in the sagittal and frontal planes and the surface area, as well as between the path length and the surface area on the SIGMA platform when compared to dancers., Conclusions: The level of dynamic and static balances of dancing people is similar, when compared to non-dancers. The influence of practicing Latin American dances on the sense of balance require further studies.

Background: In the elderly, nutrition significantly influences biological aging and physiological and pathological changes in the body. A balanced diet and physical activity are the key to good physical and mental health., Objective: The aim of this study was: (1) to perform nutritional screening tests in senior citizens residing in eastern Poland and (2) to evaluate the risk of malnutrition in elderly people who live with their families, seniors who live independently, and residents of nursing homes., Material and Method: The Mini Nutritional Assessment (MNA) screening tool comprising a questionnaire with 22 questions and an abbreviated and survey-adapted version of the questionnaire (KomPAN) were used to investigate eating habits and self-perception of health and nutrition. A total of 398 correctly filled out questionnaires were selected and the resulting data were subjected to statistical analyses in the Statistica 10 program., Results: The BMI values of most respondents were indicative or malnutrition or risk of malnutrition, regardless of gender (mean BMI 23.88 kg/m2 ±5.08). Most overweight and obese respondents were female (p=0.0001). The observed decreased BMI values was significantly (p=0.0012, rs= 0.6714) correlated with lower food intake. Unintentional weight loss greater than 3 kg was most frequently noted in respondents living in nursing homes and living independently (p=0.0021). Eating difficulties also considerably influenced the respondents' nutritional status. The respondents' BMI values were significantly correlated (p<0.0001) with their MNA scores, the average MNA score was 21.0±4.4, (rs = 0.7293). Overweight and obese respondents were more likely to consume at least three meals daily (OR=1.87; 95% CI: 1.32-2.06; p<0.001)., Conclusions: The BMI values and MNA scores of the tested subjects indicate that the majority of the surveyed respondents were malnourished or at risk of malnutrition, regardless of gender. In the present study, the residential environment significantly influenced the patients' nutritional status, in particular in respondents with impaired motor abilities and eating difficulties., Competing Interests: The authors declare no conflict of interest, (© Copyright by the National Institute of Public Health - National Institute of Hygiene.)

Background: Lifestyle factors are the key determinants of health. Diet exerts the great influence on the weight to height ratio and the body fat percentage. In addition to total energy intake, the type and quality of the diet can also play a role in the etiology of obesity in susceptible individuals., Objective: Aim of this study was to identify the dietary patterns of the Polish population and to determine the associations between these characteristics and body composition parameters. This study presents the clustering of dietary models and body composition to determine the association of these dietary patterns with BMI, physique rating (body type) or visceral fat., Material and Methods: The sample consisted of 402 respondents aged 18 to 65. Nutrition models were identified with cluster analysis. Logistic regression modelling with adjustment for confounders was applied. Three dietary-lifestyle patterns were identified., Results: Individuals belonging to the processed food model were at significantly higher risk of overweight and obesity expressed by BMI scores (OR=1.55; 95%CI: 1.26-1.89). The average BMI score was 28.19 ± 3.45 kg/m2 in the processed food model, 23.78 ±2.21 kg/m2 in the control group, and 22.17 ± 2.69 kg/m2 in the healthy nutrition model. Respondents belonging to the processed food model were also characterized by considerably higher body fat percentage (OR=1.89, 95%CI: 1.37-2.34) and higher visceral fat levels (OR=2.12; 95%CI: 1.42-2.34). Frequent intake (at least several times a week) of sweetened carbonated or non-carbonated beverages (p=0.002) and instant foods (p=0.006) were the main factors associated with the risk of higher body fat percentage and higher visceral fat levels., Conclusions: Dietary patterns have been proposed as a solution to investigating the association between food choice and body composition, and such studies focus on analyses of the entire diet, rather than on the intake of individual nutrients or food groups., Competing Interests: The authors declare no conflict of interest, (© Copyright by the National Institute of Public Health - National Institute of Hygiene.)

Obesity management options include a low-calorie diet, behavioral therapy, regular physical activity and pharmacological therapy. However, treatment failure is frequently encountered, most of these methods are ineffective, and a positive outcome is rarely maintained in the long term. In morbidly obese patients, bariatric surgery is considered the most effective treatment for obesity as well as the accompanying diseases. Bariatric surgery promotes much greater weight loss than conservative treatment, regardless of the applied surgical technique. Bariatric surgery patients should receive professional perioperative (preoperative, intraoperative and postoperative) care from a multidisciplinary team of specialists, including a bariatric surgeon, a general practitioner, a dietitian and a health psychologist. Patients require postoperative nutritional counseling to be able to stabilize their weight and maintain long-term weight loss after surgery. Patients are guided by bariatric dietitians through the process of adopting new eating habits and behavior, learning how to make healthy food choices.

Introduction: A food allergy is a group of symptoms occurring in the organism and resulting from consuming some food, where the problems are conditioned by immunological mechanisms. The symptoms may become apparent first in adulthood and they may be an initial manifestation of a latent allergy. Typical symptoms of a food allergy occur in different organs, thus not only in the digestive system, but also in the skin, respiratory system and circulatory system., Aim: To assess the frequency of food allergy onset in rural areas of the Lublin region as well as to determine which factors induce such allergies., Material and Methods: A survey was conducted, involving the participation of 340 inhabitants of rural areas. The study monitored the knowledge and situation of the disease, concerning allergens, allergy symptoms, methods of treatment and opinions regarding such treatment., Results: The analysis focused on 124 people with diagnosed allergies., Conclusions: Introducing a diet did not result in a statistically significant difference regarding elimination of the symptoms, as compared to the patients who did not follow any diet. On the other hand, pharmacological treatment causes statistically worse results than using other methods or not being treated at all. The patients in whom allergy symptoms disappeared were more convinced about the positive character of their diet than those in whom the symptoms were not eliminated. The age when the allergy becomes evident does not affect its duration, yet it matters as to the time of its later elimination. The more symptoms were experienced by a patient, the longer the duration of the allergy was.

The primary aim of the present review on phenoxyalkanoic acid herbicides-2-(2,4-dichlorophenoxy) acetic acid (2,4-D), 2-(4-chloro-2-methylphenoxy) acetic acid (MCPA), (2R)-2-(2,4-dichlorophenoxy) propanoic acid (dichlorprop-P), (2R)-2-(4-chloro-2-methylphenoxy) propanoic acid (mecoprop-P), 4-(2,4-dichlorophenoxy) butanoic acid (2,4-DB), and 4-(4-chloro-2-methylphenoxy) butanoic acid (MCPB)-was to compare the extent of their adsorption in soils and degradation rates to assess their potential for groundwater contamination. The authors found that adsorption decreased in the sequence of 2,4-DB > 2,4-D > MCPA > dichlorprop-P > mecoprop-P. Herbicides are predominantly adsorbed as anions-on organic matter and through a water-bridging mechanism with adsorbed Fe cations-and their neutral forms are adsorbed mainly on organic matter. Adsorption of anions of 2,4-D, MCPA, dichlorprop-P, and mecoprop-P is inversely correlated with their lipophilicity values, and modeling of adsorption of the compounds based on this relationship is possible. The predominant dissipation mechanism of herbicides in soils is bacterial degradation. The contribution of other mechanisms, such as degradation by fungi, photodegradation, or volatilization from soils, is much smaller. The rate of bacterial degradation decreased in the following order: 2,4-D > MCPA > mecoprop-P > dichlorprop-P. It was found that 2,4-D and MCPA have the lowest potential for leaching into groundwater and that mecoprop-P and dichlorprop-P have slightly higher potential. Because of limited data on adsorption and degradation of 2,4-DB and MCPB, estimation of their leaching potential was not possible., (© 2015 SETAC.)

A significant source of polycyclic aromatic hydrocarbons (PAH) in human diet is vegetable oils, especially those produced from plants grown in regions where the soil and the atmosphere are contaminated with these chemicals. Contamination with PAH of vegetable oils may also occur in the process of plant material drying with smoke or exhaust fumes, or in the course of extraction of that material with solvents containing trace amounts of PAH. The objective of this study was to determine the relationship between the levels of PAH present in rape seeds and the occurrence of these compounds in cultivation region and the relationship of the levels of PAH in rape seeds to thermal treatment after harvest. Rape seeds and pods from experimental fields and rape seeds subjected to thermal treatment in dryers obtained from suppliers of the raw material were examined and compared. Cleanup of extracts was performed with high-resolution size exclusion chromatography (SEC) and final determinations were by Trace Ultra/PolarisQ gas chromatography-mass spectroscopy (GC-MS). The results obtained indicated that during thermal treatment of rape seeds the concentration of PAH increased, but the levels of benzo[a]pyrene did not exceed threshold permissible levels. Data demonstrate that rapeseed cultivation in the presence of PAH results in higher levels of contaminants; however, the PAH levels still did not exceed the maximal allowable levels in Poland.