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The article presents the results of an analytical review of the literature on glass ionomer (glass polyalkenate) cements, which are widely used in dentistry. This materials consist from the powder and liquid, which form a plastic mass at mix that sets to form a solid. The composition of the powder and liquid components of glass ionomer cement has been analyzed. The solid component is powdered calcium or strontium aluminofluorosilicate glass, the liquid component is an aqueous solution of acrylic acid homopolymer or its copolymer with methylene-succinic acid, maleic acid and other monomers. Information about the range of compositions of aluminofluorosilicate glass, raw materials and melting process parameters are represented. An analysis of the curing mechanism of this dental material is also carried out. Acid-base interaction and cross-linking of polymeric acid molecules with ions extracted from glass occur at mixing the powder and liquid components. The final microstructure of the hardened glass ionomer cement is partially decomposed glass particles embedded in a matrix of calcium and aluminum polyalkenoates and coated with a layer of silica gel. The information presented in this review may be useful for a comprehensive understanding by dentists, developers of dental materials and scientific groups conducting research in this subject area of the physicochemical process of curing this material.

Optical properties of novel metal–dielectric nanocomposite materials based on opal matrices have been investigated. The position of optical resonances of nanocomposites, obtained by embedding of silver into the opal matrix by the electrothermodiffusion method, is explained by the Bragg diffraction, and an asymmetric form of resonance curves is attributed to the Fano resonance. An anomalous transmission and absorption of light by hybrid plasmon-photonic layered heterostructures, which is apparently associated with excitation of surface plasmon-polaritons, propagating along “metal–dielectric” interfaces, was revealed.

The article deals with the optimization parameters of centrally compressed step-variable stiffness rods, with the material that is able to work both within and out of proportionality. The following algorithms are developed: the maximization algorithm of loading critical parameter at the given volume of the rod material, and the minimization algorithm of the rod material volume observing the restrictions on durability and stability, taking into account the own weight of the rod. The analysis of the optimization results is carried out and the recommendations on calculation and rod design are offered.

In the course of evolution in animals and humans, a complex and effective system for providing the body with iodine in the form of various organic and inorganic compounds was developed. The metabolism of inorganic iodine has been studied quite well, in contrast to the mechanism of assimilation of its organic compounds. Among the latter, iodotyrosines, which are part of iodinated milk proteins, are of particular interest. To distinguish the peculiarities of the biotransformation of iodotyrosines in the animals' organism, their concentration and the concentration of tyrosine in blood plasma of rats after single administration of iodinated milk proteins were determined. For comparison, in parallel a group of animals received potassium iodide. The tested preparations were administered intragastrically with a probe in the form of aqueous solutions at a dose equivalent to 30 μg iodine per 1 kg of body weight. The level of mono- and diiodotyrosine in rat blood plasma was determined by HPLC with a mass spectrometer detector. The tyrosine content was determined on an automatic amino acid analyzer. The registration of the indices was carried out before the administration and 1, 4 and 24 hours after the administration of the substances. In the course of the conducted studies it was found that when iodinated milk proteins are once administered, a significant increase in the concentrations of monoiodotyrosine and diiodotyrosine is observed. The maximum level of iodinated amino acids, exceeding the control values by more than 6 fold, was recorded 4 hours after the ingestion of iodine-containing organic compounds into the body. At the same time interval, an increase in the concentration of tyrosine was observed in one of the experimental groups receiving iodinated milk protein. The simultaneous presence of tyrosine and its iodinated derivatives in blood plasma may indicate that monoiodotyrosine and diiodotyrosine are capable of being absorbed into the systemic bloodstream without metabolic transformations in the liver. Under introduction of potassium iodide, an increase in blood plasma concentration of monoiodotyrosine by 35% compared to the control was observed only after 24 hours, which may be a consequence of the activation of the thyroid gland due to the intake of an increased amount of iodine.

Metal-dielectric nanocomposite optical materials based on colloidal crystals have been prepared by electro-thermo-diffusion or magnetron sputtering of silver. Optical properties of these photonic crystals have been studied by angle-resolved reflectance and transmission spectroscopy. The interpretation of observed spectra has been made taking into account the Bragg diffraction, Fano resonance, Fabry-Perot resonance and surface plasmon-polaritons, which excitations contribute to the optical properties of plasmonic-photonic crystals.

High degree of geological-geophysical studies of crustal processes combined with analysis of 3D P-velocity model of the mantle under the Ukrainian Shield and its southern surrounding up to the depth of 2500 km allowed to correlate manifestations of defined possible super-deep fluid process with hydrocarbon-gas-condensate occurrences within the limits of Novokonstantinov ore field.

The paper deals with consideration (in light of recent geologic-geophysical data generalization and from the standpoint of specific features of continental riftogenesis) petroliferous regularities of the basement of the Northern flank of Dnieper-Donets aulacogen. Certain tectonic-geodynamic criteria of hydrocarbon pools presence within deconsolidated Archean-Lover-Proterozoic crystalline rocks are suggested.

The paper deals with consideration (in light of general regularities of continental riftogenesis) tectonic and petroliferous main features and peculiarities of Northern flank of Dnieper-Donets aulacogen taking into account the recent geologic-geophysic data.

The base of geological sections of petroliferous provinces in compositionally different rocks contains an anthraxolite‐asphaltite carbonaceous material that does not fit the classical models of naphthide or naphthoid formation. The complex nature of such material is related to the extreme variability of its chemical composition that is inconsistent with physiochemical properties and the associated (not always) hydrothermal mineralization as various sulfides, carbonates, quartz, rare metal‐phosphate assemblages, and U-bearing minerals. Study of the geochemical properties of such bitumens with the neutron activation method was hampered for a long time by the high content of radioactive elements (primarily U). During irradiation in a reactor, uranium generates a wide range of radionuclides, spectra of which are overprinted on lines of the major microelements. Implementation of the ICP-MS method in research works makes it possible to avoid such overlaps and refine significantly the precision of analysis and the increase in the number of analyzed metals. Our aim was to reveal the concentration level of microelements of various groups in bitumens and elucidate their genetic informativeness. We also attempted to compare characteristics of carbonaceous material dispersed in Carboniferous rocks of the Dneprov graben and Vendian rocks of the Nepa‐Botuoba anteclise (including the crystalline basement). The Dneprov graben includes a dark pelitomorphic polymineral material (DPPM) with inclusions of various polytypes of potassic hydromicas, paragonite, chlorite, dickite, sulfides, carbonates, and albite. The DPPM is confined to fluid-fracture cracks in Lower Carboniferous quartz sandstones at a depth of 3800‐5800 m or more [1]. The carbonaceous material consists of a mixture of anthraxolite with higher and lower kerites, although its physical properties (friability and viscosity) are more typical of asphaltites. The XSA, IR spectroscopy, and SEM data testify to the great mineralogical diversity of the DPPM complicated by the significant contribution of amorphous and semiamorphous phases [2]. Samples with a minimal (as far as possible) content of the admixture were chosen under binocular microscope for the investigation. In contrast to the Dneprov carbonaceous material, the anthraxolite‐kerite bitumens, which are dispersed in granites, the weathering crust of the basement, and Vendian sandstones and carbonates of the Nepa‐ Botuoba anteclise, are characterized by a rounded shape (due to high U and Th concentrations), conchoidal lustrous fracture, and the virtual absence of hydrothermal mineralization. Application of the track radiography method made it possible to reveal the uniform distribution of U in the carbonaceous material and the absence of secondary epigenetic enrichment. The spatial conjugation of heavy metals (Th and LREE), carbon, phosphorus, and sulfur in bitumens of the Siberian Platform (based on the characteristic X-ray radiation data) indicated that all elements mentioned above were accumulated simultaneously from a single source [3]. Logarithmic series of concentrations of even and odd elements in bitumens of the Dneprov graben (table, Fig. 1) demonstrate the following important points: (i) the distribution of even elements (except Sr, Zr, and Mo) is sufficiently consistent, while the distribution of odd elements (except Sc, V, REE, Re, Au, and Tl) is extremely inconsistent; (ii) concentrations of Cr, Ni, Zr, Mo, Cd, Pb, Th, V, Mn, Co, Cu, REE, Re, Au, Tl, and Bi are similar or higher than the clarke value for the upper continental crust [4]. The results indicate that the bitumens related to the rapid polycondensation of matter in the course of fluid system percolation in sedimentary complexes of the rift zone are characterized by an

When STARS reform efforts were launched in 2000, teacher training in assessment was seen as crucial to the success of the program. The STARS reform efforts focus on both supporting the implementation of quality classroom assessment practices and implementing a district-based accountability system. The training programs described in this article were developed in response to one or both of these needs. Two of the programs were designed to provide training to experienced teacher. The other two programs were designed to meet the needs of pre-service teachers. Evidence suggests that the training programs have had a positive impact on teacher confidence, knowledge, and skill in key areas of assessment. In addition, there also appears to be evidence, while somewhat limited, which suggests students also experience positive outcomes.

Experimental study of the iodine nanoparticles effect on the optical and electrical properties of zeolite - based matrix nanocomposite materials has been carried out. Phase transitions in the nanocomposites under study have been found.

Recently hydrocarbon potential of the Earth’s interior evaluations grows sharply. Apart from unconventional gas sources (shale gas, etc.) this phenomenon is connected with discovery of a number of oil and gas giants at the depths 4,5—10,5 km. Great depths appear to be the inexhaustible source of natural liquid and especially gaseous hydrocarbons. During 1970—1980 Ukraine (Eastern petroliferous region) hand in hand with USA was among the world’s leaders in the development of deep-seated petroliferous complexes and increasing of proved reserves at the depths more than 4—5 km. Many important regularities were revealed in Dnieper-Donets depression with elucida-tion of the reservoirs and seals nature among them. The bulk of proved reserves of great depths are concentrated within the central segment of Dnieper-Donets depression (Dnieprovsky basin) which is situated above the apical part of Dnieper-Donets superplume to be discovered by the investigators of the Institute of Geophysics NASU (according to current Earth sciences concepts such superplumes are considered as ascending flows of hypogene fluids which play a crucial role in generation and evolution of petroliferous basins). The main proved reserves and potential resources of Lower Car-boniferous are concentrated here. Their abnormal high density just in this segment are caused by the compromise of these hypogenic factors and basin rocks substratum. Many high-output wells can be bored here. Successful mastering of the great depths hydrocarbon potential within the area of Dnieper-Donets central segment will allow to increase gas production essentially (by 20—25 billions m3) within the next few years and then to go over balanced realization of other geological prospecting directions so as to secure the energy self-sufficiency of Ukraine.

The work discusses morphology, vertical and lateral distribution, and genesis of gas-seepage marks first established in the Carboniferous coal-bearing sequence of the Lvov-Volyn Basin. The abundance of gasseepage marks inPosidonia horizons confined to the basal part of the upper coal-bearing subformation is noted. The unique character of established gas-seepage marks and the necessity of their further study for the resolution of many scientific and applied problems are emphasized.

In the present study we investigated the effects of frequent, ungraded tests on graded unit tests, instructional strategy preferences, and student ratings of course and instructor effectiveness. Two developmental psychology classes were taught using instructional strategies identified as effective in the literature. In addition, the experimental (formative) class completed frequent, ungraded tests. Results indicated that the mean performance of students in the two classes did not differ on any of the unit tests. Significantly more students in the formative class indicated they would prefer to take frequent, ungraded tests in other courses. Formative and control students assigned equally high ratings of effectiveness to the course and the course instructor. Implications for future research are discussed.

Teachers spend approximately one third of their time in assessment activities, yet most states do not require a course in tests and measurement for certification. Three hundred ninety-seven teachers completed a survey of their formal measurement training, their beliefs about the ade quacy and importance of their training, influences on their measurement knowledge, and their perceived abilities in measurement. Forty-seven percent of the teachers reported that their mea surement training was somewhat or very inadequate. Most reported that they learned about testing and measurement by trial and error in their classes. Teachers who had taken less than one course in tests and measurement during their undergraduate course work were less likely to acquire measurement skills through graduate courses or inservice work than teachers who took one or more courses. Regardless of the amount of their measurement training, teachers reported that measurement skills were very important and that they considered their own abilities in measurement to be high.

Opal-based composite with silver iodide nanoparticles (AgI/opal) has been prepared by host-guest technology. Temperature and frequency dependences of electrical conductivity and those of dielectric permittivity of AgI/opal samples were measured. Size effects in this opal-based nanocomposite have been discussed.

Biotic and abiotic changes established in the middle Artinskian of several sections of the northern Timan and the western slope of the Central Urals are discussed. Data on the distribution of corals, composition of the biota as a whole, palaeotemperature and microfacies changes are presented for the first time. The determination of the stratigraphic levels is based on the new and revised biostratigraphic data. The palaeotemperature decline coincides with the maximal flooding surface and is considered as a possible cause of the ecological event triggering the turnover or extinction of many faunal groups. The event level was recognized in the coeval deposits along the Pangea shelves.

This study investigated the usefulness of computer-administered tests in the reduction of test anxiety. Two testing methods were used: (a) providing immediate item feedback and (b) allowing examinees to control the order of item administration. The results did not support the use of item feedback in reducing test anxiety. In some cases, item feedback was found to significantly increase test anxiety and decrease test performance. Similar results were found for examinee control, where test anxiety was found to be as high, and in some cases, significantly higher than that found with a fixed order of item administration.

Using an interactional approach, our study examined relationships among situational variables (time of semester, gender, adequacy of resources), personal variables (gender, priorities, and personal resources for coping), and reported stress and strain among student services professionals. The results indicate that stress varies significantly with time of semester and gender and that other personal and situational variables significantly predict stress levels. This approach to studying stress can provide useful environmental information for administrators concerned about staff and also for persons actively engaged in reducing stress levels through counseling and group work.

Faculty stress was investigated with the use of an interactional model of stress including roles, personal characteristics, coping strategies, and environmental characteristics. A random sample of 191 faculty members and 67 student-affairs staff members completed standardized measures of stress, strain, and coping resources and open-ended questions regarding sources of stress. Significant differences were found among faculty from different academic disciplines, between genders, and across semester time periods. Major stressors included time pressures, work overload, and interpersonal relationships. Body signals and poor interpersonal relationships were primary indicators of stress, and taking specific action and exercising were frequent coping behaviors. These findings have implications for administrative policy and faculty development programs.

This study investigated the effects of providing item feedback on student achievement test performance and anxiety, and how these effects may be moderated by the amount of success and students experience on the initial items of the test. Introductory statistics students were randomly assigned to six forms of a computer-based algebra test that differed in terms of (a) the difficulty of the first five items, and (b) the type of item feedback provided. Although test performance was not affected significantly by differences among the test forms, student anxiety levels were significantly increased when administered the test form using difficult initial items and providing item feedback along with a running score total. Implications for the use of item feedback in computer-based testing are discussed.

This study utilized a Latin Squares design to assess the equivalence of computerized testing methods compared to traditional pencil-and-paper formats in a clinical setting. Subjects were given an intake interview and three personality assessment instruments by either of the two administration formats at one week intervals. Subjects also completed a post-assessment evaluation instrument (semantic differential) to gauge their reactions to the testing experience. Data analysis indicated no significant differences between scores on measures of anxiety, depression, and psychological reactance, either across group or administration format. Importantly, while producing comparable results to the pencil-and-paper assessment, the computerized administration was preferred over the pencil-and-paper administration by 85% of the subjects. Discussion emphasizes the implications of this study as support for the use of computerized assessment in applied psychology.

The inherent phase instability and error of these multipliers are not inferior (as regards frequency stability) to those found in other methods of frequency multiplication.

Is the development of rationality a creative process? Is there something paradoxical about the idea that creativity can result in increasing rationality? We will argue in this chapter that rationality is indeed creatively constructed by the developing individual. If one thinks of creativity as consisting of unconstrained flights of the imagination and of rationality as strict adherence to mechanical rules of reasoning, there is indeed something paradoxical about this conclusion. The paradox dissolves, however, upon reconsideration of the definitions of both rationality and creativity.