693 research outputs found
Features of process of polishing flat surfaces of composites based on borosilicate glass with the semiconductor nanocrystals CdS[1-x]Se[x]
Recently, there is a rapid growth of interest in low-dimensional systems, which are characterized by reduced size to the nanometer range values along one, two or three directions.In such systems, the action of the translational symmetry is broken and as a result of the spatial limitations of movement of charge carriers changes the spectrum of electronic states, which becomes substantially dependent on the size of the object causing the manifestation of specific quantum size effects in the spectral dependence of the optical characteristics
FEATURES OF DENTAL IMPLANTS IN THE COMPLEX TREATMENT OF PERIODONTAL DISEASE
Aim: To Improve the treatment of patients with partial edentia and chronic generalized periodontitis by including dental implantation to the complex of therapeutic measures.
Materials and methods: There have been presented the results of 240 patients with varying severity degrees of generalized periodontitis who underwent surgery on periodontal tissues with dental implantation. The research was conducted at the OCH of Ivano-Frankivsk 2007–2017.To improve the efficiency for dental implants and periodontal surgical intervention is necessary to determine the quality of bone remodeling, identifying markers of bone tissue metabolism.
Results: It was established that in 40,81 % patients the results of research showed markers of bone remodeling indicating a high rate of bone formation (25,12±2,23 ng / ml) and a slight increase in rate of resorption marker, which results in low rates of bone resorption (8,54±1,23 nmol/L). These patients were not prescribed with osteotropic drugs. 50,83 % of patients with osteopenia were noticed to manifest the formation of bone possible raise of bone resorption (10.82±1.34n/mole), which was the indication for antiresorptive medication prescription. In 8,36 % of patients with osteoporosis was observed inhibition of bone formation processes (18,05±2,08 ng / ml) and increased resorption indices (15,34±1,87 nmol/L). Medications that stimulate osteogenesis and prevent bone resorption were prescribed.
Conclusions: When planning dental implants and periodontal surgical intervention it is necessary to identify markers of bone remodeling to assess the structural and functional state of bone tissue and prescribe osteotrophic drugs that promote positive postoperative period
Features of process of polishing flat surfaces of composites based on borosilicate glass with the semiconductor nanocrystals CdS[1-x]Se[x]
Recently, there is a rapid growth of interest in low-dimensional systems, which are characterized by reduced size to the nanometer range values along one, two or three directions.In such systems, the action of the translational symmetry is broken and as a result of the spatial limitations of movement of charge carriers changes the spectrum of electronic states, which becomes substantially dependent on the size of the object causing the manifestation of specific quantum size effects in the spectral dependence of the optical characteristics
Physical properties and crystal chemistry of Ce2Ga12Pt
Single crystals of the new ternary compound Ce2Ga12Pt were prepared by the
self-flux technique. The crystal structure with the space group P4/nbm was
established from single-crystal X-ray diffraction data and presents a
derivative of the LaGa6Ni0.6 prototype. Magnetic susceptibility measurements
show Curie-Weiss behaviour due to local Ce^3+ moments. At high temperatures,
the magnetic anisotropy is dominated by the crystal-electric-field (CEF) effect
with the easy axis along the crystallographic c direction. Ce2Ga12Pt undergoes
two antiferromagnetic phase transitions at T_N,1 = 7.3K and T_N,2 = 5.5K and
presents several metamagnetic transitions for the magnetic field along c.
Specific-heat measurements prove the bulk nature of these magnetic transitions
and reveal a doublet CEF ground state. The 4f contribution to the resistivity
shows a broad maximum at T_max ~ 85K due to Kondo scattering off the CEF ground
state and excited levels.Comment: 12 pages, accepted in J. Phys.: Condens. Matte
Charge, lattice and magnetism across the valence crossover in EuIrSi single crystals
We present a detailed study of the temperature evolution of the crystal
structure, specific heat, magnetic susceptibility and resistivity of single
crystals of the paradigmatic valence-fluctuating compound EuIrSi. A
comparison to stable-valent isostructural compounds EuCoSi (with
Eu), and EuRhSi, (with Eu) reveals an anomalously large
thermal expansion indicative of the lattice softening associated to valence
fluctuations. A marked broad peak at temperatures around 65-75 K is observed in
specific heat, susceptibility and the derivative of resistivity, as thermal
energy becomes large enough to excite Eu into a divalent state, which localizes
one f electron and increases scattering of conduction electrons. In addition,
the intermediate valence at low temperatures manifests in a moderately
renormalized electron mass, with enhanced values of the Sommerfeld coefficient
in the specific heat and a Fermi-liquid-like dependence of resistivity at low
temperatures. The high residual magnetic susceptibility is mainly ascribed to a
Van Vleck contribution. Although the intermediate/fluctuating valence duality
is to some extent represented in the interconfiguration fluctuation model
commonly used to analyze data on valence-fluctuating systems, we show that this
model cannot describe the different physical properties of EuIrSi with
a single set of parameters.Comment: 12 pages, 4 figures, 1 tabl
Magnetic impurity resonance states and symmetry of the superconducting order parameter in iron-based superconductors
We investigate the effect of magnetic impurities on the local quasiparticle
density of states (LDOS) in iron-based superconductors. Employing the
two-orbital model where 3 electron and hole conduction bands are hybridizing
with the localized -orbital of the impurity spin, we investigate how various
symmetries of the superconducting gap and its nodal structure influence the
quasiparticle excitations and impurity bound states. We show that the bound
states behave qualitatively different for each symmetry. Most importantly we
find that the impurity-induced bound states can be used to identify the nodal
structure of the extended s-wave symmetry () that is actively
discussed in ferropnictides.Comment: 7 pages, 5 figures, theory part is extended, figures are replace
Better educational signage could reduce disturbance of resting dolphins
Spinner dolphins on Hawai‘i Island’s west coast (Stenella longirostris longirostris) rest by day in protected bays that are increasingly popular for recreation. Because more frequent interactions of people with these dolphins is likely to reduce rest for dolphins and to explain recent decline in dolphin abundance, the National Oceanic and Atmospheric Administration (NOAA) proposed stricter rules regarding interactions with spinner dolphins near the main Hawaiian Islands and plans to increase enforcement. Simultaneous investment in public education about both interaction rules and their biological rationale has been and is likely to be relatively low. To test the hypothesis that more educational signage will reduce human-generated disturbance of dolphins, a paper questionnaire was distributed to 351 land-based, mostly unguided visitors at three dolphin resting bays on Hawai‘i Island’s west coast. Responses indicated that visitors wanted to see dolphins, were ignorant of interaction rules, were likely to read signs explaining rules and their biological rationales, and were likely to follow known rules. Therefore, investment in effective educational signage at dolphin resting bays is recommended as one way to support conservation of spinner dolphins on Hawai‘i Island’s west coast and similar sites in the Hawaiian archipelago
Structural investigations of CeIrIn and CeCoIn on macroscopic and atomic length scales
For any thorough investigation of complex physical properties, as encountered
in strongly correlated electron systems, not only single crystals of highest
quality but also a detailed knowledge of the structural properties of the
material are pivotal prerequisites. Here, we combine physical and chemical
investigations on the prototypical heavy fermion superconductors CeIrIn
and CeCoIn on atomic and macroscopic length scale to gain insight into
their precise structural properties. Our approach spans from enhanced
resolution X-ray diffraction experiments to atomic resolution by means of
Scanning Tunneling Microscopy (STM) and reveal a certain type of local features
(coexistence of minority and majority structural patterns) in the tetragonal
HoCoGa-type structure of both compounds.Comment: 8 pages, 5 figures, submitted to JPSJ (SCES 2013
Towards an ecological network for the Carpathians
The Carpathian Biodiversity Information System (CBIS) and the proposal for an ecological network for the eastern part of the Carpathians are the two main outcomes of the project funded by the BBI Matra program of the Dutch government. This brochure presents information on how the CBIS was designed, and how the data stored can be retrieved and used. It also clarifies how the CBIS data were used to design the ecological network and, last but not least, it offers recommendations for the use of the proposed ecological network in supporting sustainable developmentin the Carpathians. Due to funding restrictions, the project focused on three east Carpathian countries: Romania, Serbia and Ukraine, which together host the largest area of the Carpathians (Fig. 2). Geographically, the Eastern Carpathians also include parts of the Carpathians located in Poland and Slovakia. Data collection in the Western Carpathians (Czech Republic, Poland, Slovakia and Hungary) will be completed by 2010 and is funded by a parallel project
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