Critical behavior of the weakly disordered Ising model: Six-loop sqrt[ɛ] expansion study.

The critical behavior of three-dimensional weakly diluted quenched Ising model is examined on the base of six-loop renormalization group expansions obtained within the minimal subtraction scheme in 4-ɛ space dimensions. For this purpose the ϕ^{4} field theory with cubic symmetry was analyzed in the replica limit n→0. Along with renormalization group expansions in terms of renormalized couplings the sqrt[ɛ] expansions of critical exponents are presented. Corresponding numerical estimates for the physical, three-dimensional system are obtained by means of different resummation procedures applied both to the sqrt[ɛ] series and to initial renormalization group expansions. The results given by the latter approach are in a good agreement with their counterparts obtained experimentally and within the Monte Carlo simulations, while resumming of sqrt[ɛ] series themselves turned out to be disappointing.

[Nutriome as the direction of the "main blow": determination of physiological needs in macro- and micronutrients, minor biologically active substances].

One of the essential parts of fundamental research in Nutrition Science is the determination of the physiological requirements of humans for energy and food substances. Research that has been carried out in this area over the past 90 years, consistently develops and improves the norms of physiological requirements for energy and nutrients for various groups of the population of the Russian Federation. In the 50 years of the last century in this research field, determining the values of daily intake for macronutrients (proteins, lipids and carbohydrates), was in the first place. Then the Era of micronutrients (vitamins, minerals, trace elements) was started, and, finally, now there is the Era of minor food biologically active substances. More and more facts are accumulating about their leading role in regulating metabolism. They can be recognized as endogenous regulators, the primary vital components involved in the formation of human health. In recent years, the new definition of Nutriome is introduced into Nutrition Science. It is considered as a set of essential nutritional factors to maintain a dynamic equilibrium between human being and the environment, aimed to ensure viability, the preservation and reproduction of the species, keeping the adaptive capacity, the system of antioxidant defence, apoptosis, metabolism, and immune system function. The Nutriome is a formula for optimal nutrition, which is continually being improved and supplemented. Knowledge of this formula is the key to forming an optimal diet for a person, and, therefore, to save their health. It is evident that at the population level, the Nutriome has its characteristics, its structure for each age period of human life. The need to develop a formula for optimal nutrition and, consequently, updating nutrient-based dietary guidelines is induced by socio-economic and demographic changes in population, changes in anthropometric characteristics of children and adults, increasing prevalence of socially significant non-communicable diseases, developing studies of the significance of particular food substances and establishing the relationship between nutrition and health.

[An analysis of the diet of members of the Russian national men's water polo team during the sports training camps].

Increasing the adaptive capacity of professional athletes depends on proper nutrition, especially in training and competitions' period. In this regard, it is relevant to study the actual nutrition and assess its compliance with the energy expenditure of athletes. The aim - to study the actual nutrition and energy expenditure of athletes from male water polo national team of the Russian Federation in the competitive period. Material and methods. In March 2018, 15 highly skilled sportsmen-men engaged in water polo were examined; qualification - 11 masters of sports, 4 candidates for the master of sports; Slavic ethnos. The average age was 23.1±0.6 years. The actual nutrition was studied by a 24-hour food record method and by the frequency method. The anthropometric examination was carried out according to a unified method using standard medical scales, a medical height meter and a rubberized measuring tape. Measurement of energy expenditure and heart rate at rest and under load was performed on a bicycle ergometer using an wireless ergospirometer and a chest pulse meter. Results and discussion. The determination of daily energy expenditure in athletes of the men's Russian national water polo team showed that the average value was 4350±129 kcal. А peculiar feature of the diet of water polo players is its high caloric value (5165±539 kcal/day), caused by energy expenditure during physical exertion and additional thermogenesis in conditions of long training in water. Excessive (1.5 times in comparison with the recommended values) consumption of fats, including saturated fatty acids by 1.3 times, added sugar and added salt is a risk factor of cardiovascular diseases, diseases of digestive organs, endocrine system, including type 2 diabetes. Low values of consumption of vegetables and fruits, dairy products, fish products and high levels of sugar and confectionery have been established. Conclusion. The imbalance of diets on two basic nutrients (fats, carbohydrates) has been revealed. The data obtained were the basis for the formation of individual recommendations on nutrition for each athlete, taking into account athletes' metabolic parameters and the level of physical activity. It is necessary to continue studies of anthropometric indices in dynamics for the most adequate assessment of the compliance of actual nutrition with energy consumption, and further correction of the diet in order to improve athletes' performance.

[The feasibility of specialized products for nutrition of sportsmen in the preparatory period of the sports cycle].

The nutrition factor is one of the most important in the achievement of high sport results and in maintaining of athlete health along with the methodological and psychological aspects of training. Improving the methods of training in different sports leads to a significant increase in the level of energy expenditure. In order to provide athletes with a large amount of energy, it is advisable to use specialized products with increased nutritive and biological value. Specialists should pay special attention to the scientific justification of composition of special food products (SPP) with consideration of age and gender of athlete, type of sport, the stages of sports activities, training regimes, the qualifications of the athlete and individual level of metabolism. An analytical review of literature on the appropriateness of the application of SPP for athlete nutrition in the preparatory period was conducted to justify the need for further research in this field.

[Basal metabolic rate as an integral indicator of metabolism intensity].

The basal metabolism rate (BMR) is of great importance in the assessment of daily energy requirements and physical activity level of a person. Article reviews the factors influencing the BMR. The BMR significantly correlates with weight, height, age, sex. Prediction equations based on these factors account for approximately 70% of the variability of the basal metabolism. However, these equations do not take into account the effect of body composition. The BMR is associated with lean body mass. Among body composition indicators lean body mass is the strongest determinant of BMR. The rate of basal metabolism, predicted on the basis of the relationship with the lean body mass covers the same 70% of the variability that are determined by gender and age differences, as most of the variability due to gender and age differences. In addition, the role of physical activity and nutrition as factors that affect the value of the BMR is discussed. The conclusion is made that lean body mass is the strongest predictor of BMR. Body fat mass also affects the basal metabolic rate as well as physical activity level and nutrition.

Anisotropy of a cubic ferromagnet at criticality.

Critical fluctuations change the effective anisotropy of cubic ferromagnet near the Curie point. If the crystal undergoes phase transition into orthorhombic phase and the initial anisotropy is not too strong, reduced anisotropy of nonlinear susceptibility acquires at T_{c} the universal value δ_{4}^{*}=2v^{*}/3(u^{*}+v^{*}) where u^{*} and v^{*} are coordinates of the cubic fixed point on the flow diagram of renormalization group equations. In the paper, the critical value of the reduced anisotropy is estimated within the pseudo-ε expansion approach. The six-loop pseudo-ε expansions for u^{*}, v^{*}, and δ_{4}^{*} are derived for the arbitrary spin dimensionality n. For cubic crystals (n=3) higher-order coefficients of the pseudo-ε expansions obtained turn out to be so small that use of simple Padé approximants yields reliable numerical results. Padé resummation of the pseudo-ε series for u^{*}, v^{*}, and δ_{4}^{*} leads to the estimate δ_{4}^{*}=0.079±0.006, indicating that detection of the anisotropic critical behavior of cubic ferromagnets in physical and computer experiments is certainly possible.

[Non-enzymatic glycosylation of dietary protein in vitro].

Non-enzymatic glycosylation of proteins, based on discovered by Mayarn reaction of carbohydrate aldehyde group with a free amino group of a protein molecule, is well known to experts in biochemistry of food industry. Generated brown solid in some cases give the product marketable qualities--crackling bread--in others conversely, worsen the product. The biological effects of far-advanced products of non-enzymatic protein glycosylation reaction have not been studied enough, although it was reported previously that they are not split by digestive enzymes and couldn't be absorbed by animals. The objective of this work was to compare the depth of glycosylation of different food proteins of animal and vegetable origin. The objects of the study were proteins of animal (casein, lactoglobulin, albumin) and vegetable (soy isolate, proteins of rice flour, buckwheat, oatmeal) origin, glucose and fructose were selected as glycosylation agents, exposure 15 days at 37 degrees C. Lactoglobulin was glycosylated to a lesser extent among the proteins of animal origin while protein of oatmeal was glycosylated in the least degree among vegetable proteins. Conversely, such proteins as casein and soya isolate protein bound rather large amounts of carbohydrates. Fructose binding with protein was generally higher than the binding of glucose. The only exception was a protein of oatmeal. When of glucose and fructose simultaneously presented in the incubation medium, glucose binding usually increased while binding of fructose, in contrast, reduced. According to the total amount of carbohydrate (mcg), which is able to attach a protein (mg) the studied food proteins located in the following order: albumin (38) > soy protein isolate (23) > casein (15,) > whey protein rice flour protein (6) > protein from buckwheat flour (3) > globulin (2) > protein of oatmeal (0.3). The results obtained are to be used to select the optimal combination of proteins and carbohydrates, in which the glycosylation during storage will be minimal.

[The study of the peculiarities of metabolism in individuals with rs9939609 polymorphism of FTO gene].

A total of 104 people, among them were 18 men and 86 women aged 18 to 67 years--people in the Moscow region of the Russian Federation, in the sanatorium treatment. Association embodiment rs9939609 FTO obesity was studied using allele-specific amplification, detection results in real time using TaqMan-probes complementary DNA polymorphisms. The frequency of the mutant allele in individuals was 47.0%, while the TT genotype was detected in 25.0% of cases, AT--in 56.0%, AA.0%. In men, prevalence rates of obesity risk allele (A) is higher than in women. In individuals with obesity (BMI over 30 kg/m2) indicated the presence of more AA genotypes (2 7.8%) compared to individuals with a body mass index of less than 30 kg/m2 (14.1%) and a high frequency of occurrence (54.2 versus 43.0%) risk allele A. Compared with individuals with genotype TT, the examinees with the AA genotype rs9939609 FTO gene was significantly higher BMI, waist circumference, hip circumference, fat mass. The same patients energy expenditure at rest value, calculated per kg of lean body mass or muscle, was slightly less than with TT genotype. In individuals with the AA genotype rs9939609 FTO gene compared with the TT genotype had significantly lower levels of HDL cholesterol and serum iron in the background significantly elevated concentrations of uric acid. Thus, the evaluation of patients with the use of innovative technologies in a spa treatment allows their personal alimentary correction for the prevention and treatment of non-communicable diseases.

Pseudo-ε expansion and renormalized coupling constants at criticality.

Universal values of dimensional effective coupling constants g(2k) that determine nonlinear susceptibilities χ(2k) and enter the scaling equation of state are calculated for n-vector field theory within the pseudo-ε expansion approach. Pseudo-ε expansions for g(6) and g(8) at criticality are derived for arbitrary n. Analogous series for ratios R(6) = g(6)/g(4)(2) and R(8) = g(8)/g(4)(3) that figure in the equation of state are also found, and the pseudo-ε expansion for Wilson fixed point location g(4)(*) descending from the six-loop renormalization group (RG) expansion for the ß function is reported. Numerical results are presented for 0 ≤ n ≤ 64, with the most attention paid to the physically important cases n = 0,1,2,3. Pseudo-ε expansions for quartic and sextic couplings have rapidly diminishing coefficients, so Padé resummation turns out to be sufficient to yield high-precision numerical estimates. Moreover, direct summation of these series with optimal truncation gives values of g(4)(*) and R(6)(*) that are almost as accurate as those provided by the Padé technique. Pseudo-ε expansion estimates for g(8)(*) and R(8)(*) are found to be much worse than those for lower-order couplings independently of the resummation method employed. The numerical effectiveness of the pseudo-ε expansion approach in two dimensions is also studied. Pseudo-ε expansion for g(4)(*) originating from the five-loop RG series for the ß function of two-dimensional λϕ(4) field theory is used to get numerical estimates for n ranging from 0 to 64. The approach discussed gives accurate enough values of g(4)(*) down to n = 2 and leads to fair estimates for Ising and polymer (n = 0) models.

Fisher exponent from pseudo-ε expansion.

The critical exponent η for three-dimensional systems with an n-vector order parameter is evaluated in the framework of the pseudo-ε expansion approach. The pseudo-ε expansion (τ series) for η found up to the τ(7) term for n = 0, 1, 2, 3 and within the τ(6) order for general n is shown to have a structure that is rather favorable for getting numerical estimates. The use of Padé approximants and direct summation of the τ series result in iteration procedures rapidly converging to the asymptotic values that are very close to the most reliable numerical estimates of η known today. The origin of such an efficiency is discussed and shown to lie in the general properties of the pseudo-ε expansion machinery interfering with some peculiarities of the renormalization group expansion of η.

Critical exponents in two dimensions and pseudo-ε expansion.

The critical behavior of two-dimensional n-vector λϕ4 field model is studied within the framework of pseudo-ε expansion approach. Pseudo-ε expansions for Wilson fixed-point location g* and critical exponents originating from five-loop two-dimensional renormalization-group series are derived. Numerical estimates obtained within Padé and Padé-Borel resummation procedures as well as by direct summation are presented for n=1, n=0, and n=-1, i.e., for the models which are exactly solvable. The pseudo-ε expansions for g*, critical exponents γ, and ν have small lower-order coefficients and slow increasing higher-order ones. As a result, direct summation of these series with optimal cutoff provides numerical estimates that are no worse than those given by the resummation approaches mentioned. This enables one to consider the pseudo-ε expansion technique itself as some specific resummation method.

[Body composition and energy metabolism at rest].

Indicators of body composition determined by bioelectrical impedance analysis (total body water, extracellular water mass, intracellular water mass, skeletal muscle mass, soft lean mass, protein, mineral mass, fat mass) were compared with the resting metabolic rate values (RMR). Studies were conducted in adults of different occupations, gender, age, weight and height. In total, the survey involved 180 people, residents of Nizhny Novgorod (70 men and 110 women) aged 17 to 63 years. It was shown that the normalization of the RMR with the parameters of the bioelectrical impedance analysis reduced the scatter of individual values. Comparison of the normalization results allowed us to estimate the interconnection between the RMR and the body composition. It was obtained statistical formulas for the relation of the RMR with the bioelectrical impedance. The greatest effect was found with the normalization of lean mass, as well as intracellular and extracellular water masses. The smallest effect was detected with the normalization of body fat. We obtained statistical formulas for the relation of the RMR with the bioelectrical impedance parameters. The highest correlations were found between the RMR and the lean mass, muscle mass and total water mass, the lowest with the fat mass. Role of the metabolically active tissue in energy metabolism, including the role of the intracellular and extracellular water is discussed. The results confirm the importance of the metabolically active tissues in the formation of the value of the RMR. Identified dependencies and high correlation between the RMR and the bioelectrical impedance parameters allows us to use these as a fast and convenient method for the approximate estimation of the RMR.

[Energy expenditure and food energy intake in different professional groups of N. Novgorod].

In this paper we have studied the energy expenditure and food energy consumption of different professional groups of the adult population of the city N. Novgorod. Assessment of daily energy expenditure was performed using the coefficients of physical activity (CPA) in the working period, the free time and the total daily average activity. It is shown that the rest time averaged 40-50%, while physical activity time 60-50%, respectively. The ratio of physical activity duration to rest duration was similar in the groups with different CPA. It was revealed that the proportion of energy expenditure associated with physical activity accounted for 70-80% and was higher in the groups of occupations with a higher work intensity. It was found that on the amount of daily physical activity the CPA of the working period has a more significant impact than the CPA of the rest time. To estimate the energy intake we use data on the chemical composition and energy value of the diet. The use of the relationship of dietary energy to the value of basal metabolism allowed to compare the values of energy expenditure between different professional groups. The advantage of the new energy expenditure unit is that it, as well as the CPA, is practically independent of sex, age, height and weight. Analysis of the relationship of energy consumption and energy expenditure did not reveal any dependence on the activity in the working period or the daily physical activity. Based on these data we discuss the feasibility of normalization of the physical activity and the prevention of sedentary lifestyles.

[Contemporary methods of daily energy expenditure measurement in the system of the nutritional status estimation].

Daily energy expenditure measurement have great significance in such fields of research as nutrition, medicine, sport, physical activity, way of life, etc. Article is dedicated to the survey of the principal methods of the energy expenditure measurement: direct calorimetry, the double labeled water method, indirect calorimetry, heart rate monitoring, and accelerometry. For evaluating the daily energy expenditure most informative is the combination of indirect calorimetry, heart rate monitoring and accelerometry.

[Influence of modified food starches on composition and phagocytic activity of peritoneal cells].

Modified maize starches having differences in the number of crosscut lacings in the structure, and in the abilities to be gelatinized in the cold water were used: native maize starch "Novation 4600", acetylated adipat di-starch of the cold swelling "Prejeflo CH 20", acetylated adipat di-starch of the cold swelling "Prejeflo CH 40", acetylated adipat di-starch of the hot swelling "Clearam CH 2020". All investigated starches possessed the ability to activate neutrophils and to increase their phagocytosis 2 h after i.p. administration. Four days after i.p. injection, starches and their hydrolyzet starch products were shown to stimulate the neutrophils and lymphocytes into peritoneal cavity. Starch digest products have the more stimulated capacities compared with native compounds that indicates the possible immune activity of starch carbohydrate chain fragments.

[Physical, chemical and biological properties of food modified starches].

Aim of work was to compare the chemical and biological properties of starches modified by adipinic acid acetylation. Starches in question were: native maize starch "Novation 4600"; acetylated adipat di-starch of the cold swelling "Prejeflo CH 20"; acetylated adipat di-starch of the cold swelling "Prejeflo CH 40"; acetylated adipat di-starch of the hot swelling "Clearam CH 2020". The differences between starches were connected with number of cross-cut lacings in the structure, and with abilities to be gelatinized in the cold water. Rate of hydrolysis and water-retaining capacities were higher for cold swelling starches which contained the smaller number of resistance fractions. Acetyl value of cold swelling starches was higher under elevation of cross-cut lacing.

[Energy requirements in adolescents playing basketball in Russian Olympic reserve team]. / Potrebnost' v energii basketbolistov-podrostkov iz komandy olimpiiskogo rezerva Rossii.

The energy expenditure and requirements and dietary intake were studied in basketball players aged 14-16 years during 3 week-training period. The subjects of study were 14 boys and 18 girls as of the members of reserve of Russian Olympic basketball team. The dietary intake was estimated by dietary record of all food consumed within 24 hours last 7 days of training period. The energy expenditure was estimated by registration of time on different physical activity of team and multiplication on physical activity coefficient. The decrease of body mass and body mass index were observed in boys with height 195 cm and more to the end of training period. These tall boys did not consume enough food to satisfy the estimated energy requirement. It is estimated that energy need of tall basketball players is no less then 5000 kcal for boys and 3100 kcal for girls.

[Utilization of glucose, valine, glycerin and palmitic acid by energy and anabolic pathways of metabolism in rats]. / Utilizatsiia gliukozy, valina, glitserina i pal'mitinovoi kisloty po énergeticheskomu i anabolicheskomu puti metabolizma u krys.

Possibility of evaluation of nutrients use by energy and anabolic ways by measurement in blood of radioactivity of water formed from labelled by tritium precursors was studied. The experiment was made on rats, which consecutively with interval 1.5-2 weeks were given intravenous indicative amount of 3H2(2,3)-valine, 1-14C-glucose, 6-3H-glucose, 3H2(1,3)-glycerin and 3H2(9,10)-palmitic acid. Half-time of glucose in blood was 46 min, glycerin--16 min, valine and palmitic acid--24 min. Plastic and energy characteristics of these substances were studied. The proposed approach to the evaluation of plastic and energy functions of nutrients can be useful for development of specialized products for enteral and parenteral feeding.

Universal critical coupling constants for the three-dimensional n-vector model from field theory.

The field-theoretical renormalization group (RG) approach in three dimensions is used to estimate the universal critical values of renormalized coupling constants g6 and g8 for the O(n)-symmetric model. The RG series for g6 and g8 are calculated in the four- and three-loop approximations, respectively, and then resummed by means of the Padé-Borel-Leroy technique. Under the optimal value of the shift parameter b providing the fastest convergence of the iteration procedure, numerical estimates for g*6 are obtained with an accuracy no worse than 0.3%. The RG expansion for g8 demonstrates a stronger divergence, and results in considerably cruder numerical estimates.