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The possibility of analyzing multidimensional data for predicting properties of petroleum road asphalts is examined. Construction of a prognostic model helped determine the optimal feedstock composition and technological parameters of the oxidation process for getting improved asphalts. The positive and negative correlating variables, viz., feedstock properties, oxidation process parameters, and properties of oxidized asphalts, are determined from the data set. The analysis results were used to develop a technology for producing improved asphalts under conditions of asphalt production by OAO Syzranskii NPZ (OJSC Syzran Refinery).

Qualification comparable groups of young men engaged in cyclic kinds of sports were tested with stepwise accruing loads on bicycle ergometer and 25-minute exponential increasing normobaric hypoxia to final concentration of 10% oxygen. Group of skiers, having the greatest values of the maximal oxygen consumption at muscular work, show the relaxed cardiorespiratory reactions and more falling of blood oxygen in the hypoxia. The swimmers, having restrictions of ventilatory function in the course of trainings, form preadaptation to hypoxia with changes of external respiration and gas exchange functions that allows at hypoxia to better oxygen sate the blood in lungs. The joint assessment of aerobic capacity at physical work and physiological reactions to hypoxia shows the direct relation between individual maximal oxygen consumption and the descent rate of blood oxygen saturation at accruing hypoxia that can be useful at an assessment of a sportsman functional state and its correction at training processes.

Ferrite Ni0.75Zn0.25Fe2O4 was prepared by the solid-state synthesis and thermal decomposition of the complex oxalate Ni0.75Zn0.25Fe2(C2O4)3 · 6H2O. The oxalate precursor and the products obtained at different stages of the thermal decomposition were identified by differential thermal analysis and X-ray and X-ray photoelectron spectroscopy. The properties of a ferromagnetic coating deposited on a substrate by gasflame coating were studied. The magnetic properties of the Ni-Zn ferrite product and the ferromagnetic coating were also investigated.

Changes in the concentration of solute molecules in a glycerol matrix were studied using mass spectrometry of secondary ions that appeared under the bombardment of a sample-solution by primary ions. The objects of study were several organic dyes and glucose oxidase. The concentration of solute molecules in the surface layer of the matrix was determined by the competition between the destruction of analyte molecules by primary ions and the replenishment of the number of undamaged molecules as a result of diffusion from the bulk.

The paper discusses possible signs of time variation in the constants for the extended standard model. Existing experimental constraints on the magnitude of the changes are given in order to allow for the possible effects on the metrological characteristics of primary standards for the units of physical quantities.

The constants in the extended standard model are considered, which includes gravitational interaction and massive neutrinos. The accuracy is compared in determining the coupling constants on various energy scales, and theoretical estimates are given for the possible time variations.

Enzymatic glucose oxidation in a system modeling a glucose biosensor have been investigated by SIMS with the use of a liquid matrix. The effect of some solution parameters on the reaction product (gluconic acid) yield has been analyzed. It is shown by an example of gluconolactone hydrolysis that SIMS makes it possible to study not only final but also intermediate stage of the glucose oxidation reaction.

Some methods of determining the constants of the Standard Model, the values of the constants established at the present time, and the dependence of the coupling constants of the strong, electromagnetic and weak interactions on the characteristic energy of the process are presented. Possible generalizations of the Standard Model, which lead to a reduction in the number of fundamental constants, are considered.

The paper discusses the fundamental physical constants, the classification of them, the number of them, the definition accuracy, and the relationships to fundamental physical theories (interactions). Basic concepts are presented on gravitational relativistic metrology related to precision space-time measurements. The main attention is given to Newton’s gravitational constant G as regards the measurement of the absolute value and the possible variations in time and space as predicted by interaction union theories. Principles are presented for a proposed space experiment to measure G and its variations, whose implementation will enable one to improve on current data from appropriate laboratory experiments on Earth by 2–3 orders of magnitude.

The ultrasonic location technique was used to measure intima-media thickness (IMT), as well as internal systolic diameter of and linear blood velocity in the cervical arteries in people with initial hypertension. Correlation analysis elicited a temporal contingency between these parameters and daily average values of atmospheric pressure. Thus, common carotid artery IMT tended to increase on high-pressure days. Besides, diameters of the common and internal carotid arteries, and vertebral artery were narrowed and, consequently, linear blood velocity in these vessels increased. This relationship is more evident in men than women and in elderly subjects than young. These results are suggestive of a vasoconstrictive action of high atmospheric pressure on these arteries. The relationship is not universal, as it is nonlinear for diameter of the internal carotid artery and inverse for the external one. This implies different sensitivity of arteries to the factor under study and possible blood redistribution in the arterial basin depending on external pressure. The relationship was observed equally on the day of investigation and previous days, which points to its temporal stability.

Qualification comparable groups of young men engaged in cyclic kinds of sports were tested with stepwise accruing loads on bicycle ergometer and 25-minute exponential increasing normobaric hypoxia to final concentration of 10% oxygen. Group of skiers, having the greatest values of the maximal oxygen consumption at muscular work, show the relaxed cardiorespiratory reactions and more falling of blood oxygen in the hypoxia. The swimmers, having restrictions of ventilatory function in the course of trainings, form preadaptation to hypoxia with changes of external respiration and gas exchange functions that allows at hypoxia to better oxygen sate the blood in lungs. The joint assessment of aerobic capacity at physical work and physiological reactions to hypoxia shows the direct relation between individual maximal oxygen consumption and the descent rate of blood oxygen saturation at accruing hypoxia that can be useful at an assessment of a sportsman functional state and its correction at training processes.

In order to verify associations between solar and geomagnetic activities and perinatal variables the monthly distributions of population characters in Novosibirsk region over the period 1980-2001 were compared by stepwise correlation analysis with monthly averaged physical parameters at lags from 0 to 10 months. Three indices used were as follows: the number of sunspots, solar flux at 10.7 cm wavelength and Ak index measured at local ionospheric station near Novosibirsk city. Official data on the number of single and multiple live births, stillbirths and infant deaths at the age under one year by the type of population and sex were provided by State Statistical Committee. All three physical parameters positively correlated with the number of single births and infant mortality rate and negatively with twin births in both populations, urban and rural, irrespective of lags. The direct association between Ak index and relative number of stillbirths in urban setting was mostly pronounced at a lag of 5 months. The number of live births increased along with Ak index due to the enhanced proportion of female births whereas the number of stillbirths after the increase in solar and geomagnetic activities elevated because of male deaths.

Exact static, spherically symmetric solutions to the Einstein-Maxwell-scalar equations, with a dilatonic-type scalar-vector coupling, in D-dimensional gravity with a chain of n Ricci-flat internal spaces are considered. Their properties and special cases are discussed. A family of multidimensional dilatonic black-hole solutions is singled out, depending on two integration constants (related to black hole mass and charge) and three free parameters of the theory (the coordinate sphere, internal space dimensions, and the coupling constant). The behaviour of the solutions under small perturbations preserving spherical symmetry, is studied. It is shown that the black-hole solutions without a dilaton field are stable, while other solutions, possessing naked singularities, are catastrophically unstable.

The paper presents experimental data supporting a hypothesis that the changes of arterial blood haemoglobin saturation during breathing the hypoxic gas mixture (10-13% O2) can be fitted by exponential function. The formal description of the saturation curves allowed verifying their stages and evaluating interindividual variability. It is suggested that the parameters of exponents can be used when estimating an individual hypoxic resistance of a human organism.

Single and double examinations of normal males and females in the course of 11-year solar cycle with the use of oscillovasometry and occlusive plethysmography established a direct correlation between the effective diastolic radius of the brachial artery and solar activity characteristics on the day of examination, i.e. number of solar spots and intensity of radiation with the 10.7 cm wavelength. Other blood flow parameters demonstrated opposite correlations with the factors in males and females. As solar activity increased, females displayed linear decrements of arterial elasticity and regional peripheral resistance and growth of the volumetric blood flow velocity equally at rest and at the peak of post-occlusion reactive hyperemia. In males, the correlations had the reversed sign. Besides, males were noted to reduce venous reserve and venous outflow from antebrachial muscles proportionally to the increase of Wolf number. It is inferred that elevated solar activity may be responsible for impairment of the feeling of well-being of people with reduced cardiovascular reserve, particularly in space tight or at high altitudes in the absence of or under weak protection of the geomagnetic field and ozone layer.

An attempt is made to explain the possible occurrence of an additional non-Newtonian interaction of Yukawa type in the framework of a generalized theory of gravitation with allowance for nonmetricity. Cosmological solutions are also considered.

A soliton-like time-dependent solution in the form of a running wave is derived of a self-consistent system of the gravitational field equations of Einstein and Born-Infeld type of equations of a nonlinear scalar field in a conformally flat metric. This solution is localized in space and possesses a localized energy. It is shown that both the gravitational field and the nonlinearity of the scalar field are essential to the presence of such a localized solution. In recent years various classical particle models have been widely discussed which are static or time-independent solutions of nonlinear equations with localization in space and which possess a finite field energy. In particular, soliton solutions [1], solutions in the form of eddies [2], and so on have been derived and investigated. All these solutions were treated in a flat space-time. It is of interest to derive the analogous particle-like solutions with the gravitational field taken into account; in particular it is of interest to investigate the roles of the gravitational field in connection with the formation of localized objects. These problems have been discussed in [3] in the static case. We will present below a soliton-like time-dependent solution in the form of a solitary running wave as an example of the inter-action of a Born-Infeld type of nonlinear scalar field and an Einstein gravitational field in a conformally flat metric.

It is shown that a conformally invariant scalar field can have anomalous vacuum expectation values in a Tolman universe of any kind: closed, quasi-Euclidean, or open. The anomalous vacuum expectation values lead in the initial stages of evolution of the universe to the existence of negative energy in the closed and quasi-Euclidean models if the square of the unrenormalized mass is negative and, in the open model, if the square of the unrenormalized mass is less than the square of the Planck mass. The influence of the negative energy on cosmological models of any type with and without Λ term is investigated. It is shown that there is no singular state.

A theoretical and experimental investigation is made of the electron-beam-controlled method of synthesizing nitrogen-containing compounds. It is shown that the basic chemically active form of nitrogen in the electron-beam-controlled discharge are the vibrationally excited molecules N2. The experimental procedure and the results are meported on the synthesis of nitrogen oxides, hydrogen cyanide, and phosphorus nitride. The isotopic compositions of the vibrationally excited nitrogen and carbon monoxide are calculated.

lomb) and the units of magnetic- and electric-field strength and electric and magnetic induction and thus becomes a part of the system of electromagnetic units. In an ampere balance, the electromagnetic force of the interacting currents, which is proportional to the square of the current I flowing through the electromagnetic system, is balanced by a weight on the other pan of the balance: i/c 2 I2f = mg. Here, f is a dimensionless function of the geometric parameters of the system, c is the velocity of light, m is the mass of the weight, and g is the free-fall acceleration. Finally, the scale of the ampere unit is determined by a combination of fundamental physical constants - the gravitational constant G and the velocity of light c: I = cr - and by two standard units (mass and length) and a dimensionless function. The dependence of the dimensions of units of physical quantities on the fundamental constants is not single-valued; it is determined by the operative system of physical units. Recently (in 1983), the unit of length (the meter) was redefined as the distance traversed by light in some portion of a second: ~s = cat. The second is defined as the frequency of hyperfine splitting of a cesium atom. As a result, as is readily apparent, the velocity of light disappears from the units of the electromagnetic quantities (ampere, coulomb, tesla, etc.): I = ms ~s f~- The gravitational constant, however, re~ains in the system of electromagnetic units. Obviously, quantum units of the volt~ ohm, and ampere will be used in the near future, but this gives rise to a new problem ~which is automatically solved in the present definition of the ampere) - the problem of consistency of the systems of electromagnetic and mechanical quantities. It is possible that the ampere balance (or a variation of it) will continue to be used for this purpose for a considerable period of time. Explicitly or implicitly, the gravitational constant is a part of a number of standards of mechanical units: pressure, acoustic pressure, etc.

Particlelike static spherically symmetric solutions to massless scalar and electromagnetic field equations combined with gravitational field equations are considered. Two criteria for particlelike solutions are formulated: the strong one (solutions are required to be singularity free) and the weak one (singularities are admitted but the total energy and material field energy should be finite). Exact solutions for the following physical systems are considered with their own gravitational field: (i) linear scalar (minimally coupled or conformal) plus electromagnetic field; (ii) the same fields with a bare mass source in the form of charged incoherent matter distributions; (iii) nonlinear electromagnetic field with an abritrary dependence on the invariant F/sub alphabeta/F/sup alphabeta/; and (iv) directly interacting scalar and electromagnetic fields. Case (i) solutions are not particlelike (except those with horizons, in which static regions formally satisfy the weak criterion). For systems (ii), examples of nonsingular models are constructed, in particular, a model for a particle--antiparticle pair of a Wheeler-handle type, without scalar field and explict electric charges. Besides, a number of limitations upon nonsingular model parameters is indicated. Systems (iii) are proved to violate the strong criterion for any type of nonlinearity but can satisfy the weak criterion (e.g., the Born--Infeld nonlinearity). Formore » systems (iv) some particlelike solutions by the weak criterion are constructed and a regularizing role of gravitation is demonstrated. Finally, an example of a field system satisfying the strong criterion is given.« less

The concept of a particlelike solution of the equations for interacting fields with allowance for gravitation is discussed. An example of a nonsingular spherically symmetric solution is obtained for interacting scalar and electromagnetic fields in the general theory of relativity; the regularity of the metric is ensured by the finiteness of the matter and total energies, and by the equivalence principle. It is shown that these conditions are also satisfied with interacting fields that are singular at the center.

An open isotropic cosmological model is considered, with nonzero cosmological constant and consideration of spontaneous disruption of symmetry and vacuum polarization. It is shown that consideration of quantum effects leads to the absence of initial singularity and de Sitter expansion. The problem of the vacuum energy-momentum tensor corresponding to fields ϕ of a quantum nature is considered.

We discuss a heurisitic model of gravitational vacuum as a set of virtual, radiating planckeons, particles with Planck size (L) and mass (ħ/cL). Combined with Dirac's large number hypothesis, this gives the minimum universe scale factor valuea min∼10−13 cm, the strong interaction length (a = L just whena=a min ). Taking this state as an initial one using standard quantum techniques, we consider particle creation by planckeons. Under some reasonable assumptions we obtain the present number of particles with nucleon mass close to observations,N ∼ 1080. A criterion for gravitational stability of particles is formulated and some applications of the corresponding mass formula are considered. In particular, Fermi's weak interaction constant is expressed in terms ofa andL and a finite value for the neutrino mass is obtained.

Exact solutions are obtained for a hydrogen-like atom in an external cosmological field of the closed and open universe. It is found that in the closed model, in addition to a gravitational analog of the Stark effect, there is a new effect-atom ionization by the gravitational field. In the open model, discrete and continuous spectra are obtained; furthermore, discrete spectrum consists of a finite number of states, and in the continuous spectrum the effect of the proton field is preserved despite absence of a bound state. It is shown that transition frequency depends on the radius (age) of the universe in both models, and, consequently, a hydrogen-like atom, in principle, cannot serve as a reference of time-frequency-length.

By subjecting steel powders to hydrostatic pressing with subsequent sintering, re-pressing, and annealing, it is possible to produce parts having the required shape and a density uniformly distributed throughout their volume.

The structure of the triterpene glycoside fromGypsophilla acutifolis Fisch. has been established.

1. It has been shown that the roots ofClematis vitalba contain free hederagenin and oleanolic acid and also eight glycosides of these aglycones. 2. It has been established that vitalbosides F, G, and H contain in their carbohydrate moiety an unusual monosaccharide for saponins — ribose.

The structure of a ribose-containing triterpene glycoside consisting of a hederagenin pentaoside has been established.

Control rats manifested an unmarked circadian rhythm in blood sugar during evening hours. The morning-evening difference in blood sugar increased after adrenalectomy, disappeared after weekly substitution therapy with cortisol and was inverted after evening injections of cortisol to rats with intact adrenals. Evening injections of the hormone were also more efficacious from the standpoint of glucose tolerance modulation.

A biphasic circadian rhythm in the content of liver lipid peroxidation products has been demonstrated in male Wistar rats housed under the conditions of 12L: 12D, with 3 hours of morning and evening twilight. Maxima of the concentration of the products were observed in the morning and early at night. The rhythm of lipid anti-oxidative activity was found in an anti-phase. Inversion of both the L: D cycle and glucocorticoid circadian rhythms (cortisol injections) led after 14-16 days to the same shifts in the rhythm of anti-oxidative activity. The data indicate that glucocorticoids modulate the diurnal rhythms of lipid anti-oxidative activity and may be responsible for the shifts in the rhythms of free radical oxidation, induced by inversion of the L: D cycle.

Male Wistar rats housed under the conditions of 12L : 12D, 24 +/- 1 degree C and free access to food and water received isotonic sodium chloride solution or cortisol in doses of 2 and 4 mg/kg, respectively. Daily stress or cortisol injections in the morning or evening are the synchronizers of 11-hydroxycorticosteroid excretion rhythm. Morning stress leads to the increase of the 12-hour rhythm. On the contrary, evening stress or cortisol administration during maximal endogenous secretion of corticosteroids are associated with the elevation of circadian periodicity. Exogenic changes in the rhythmic organization of the hypothalamo-hypophyseal-adrenocortical system are followed by activation of adaptive processes involved in the normalization of the initially modified glucocorticoid rhythm.