127 research outputs found

    Medical photography

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    The photography is a method for creating a permanent image of an object through designing the image on a light-sensitive media (film or sensor). The word ā€œphotographyā€ comes from greek (ā€œphotosā€ - light and ā€œgraphoā€ - write) and means ā€œlight-writingā€, or, in other words, a method of producing photographic image by using light and according to the laws of optics.(1)Specific qualities of the photography are its objectivity and documentary.It records events, phenomena in nature, events from common life, personalities - everything that leaves a lasting memory of what happened before. And not only. With the help of the photography, we can create convincing and realistic works that through their deep impact develop mental capabilities and enrich the cultural knowledge of every thinking person, create new, different ideas for the outside world, evoke feelings, thoughts and emotions.(2)Due to its rapid development, especially in the recent ā€œdigitalā€ years, photography became an integral part of all spheres of life. Besides being a documentary tool, it is also an extremely powerful method of research and analysis for inaccessible to the human eye spheres and phenomena - the processes that takes place in an environment unattainable for man, studying the atomic nucleus, exploring the secrets of the cosmic space, observations on the functionality of the human organism and many others

    Limb evolution in crested newts (Triturus cristatus complex, Salamandridae, Caudata)

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    Integracija, modularnost i razvojna ograničenja predstavljaju važne komponente fenotipske varijabilnosti. U ovoj tezi analiziran je uticaj ovih komponenti na morfoloÅ”ku evoluciju ekstremiteta pet vrsta velikih krestatih mrmoljaka. Veliki krestasti mrmoljci predstavljaju važne model organizme za istraživanja u oblasti morfoloÅ”ke integracije i razvojnih ograničenja, posebno ako se analiziraju ekstremiteti. To je grupa blisko srodnih vrsta sa poznatim filogenetskim odnosima, i izraženom vezom izmedju morfoloÅ”ke forme/tipa (oblika tela i dužine ekstremiteta) i preference prema akvatičnoj/terestričnoj sredini. Akvatične vrste se odlikuju izduženim telom i kratkim nogama, dok su vrste sa viÅ”e terestričnim životnim stilom snažnije i robusnije građe sa dugim nogama. Takođe, kao grupa sa složenim životnim ciklusom, gde larveni, juvenilni i adultni stupanj imaju različite morfologije, ekoloÅ”ke sredine i preference, načine ishrane i lokomocije, veliki krestasti mrmoljci imaju posebno mesto u izučavanju ontogenetskih putanja tokom razvića. Ontogenetska promena niÅ”e i tranzicija između akvatične i terestrične sredine je povezana sa procesom metamorfoze. Iako ekstremiteti mrmoljaka ne prolaze kroz drastične promene strukture tokom tog procesa, funkcionalni zahtevi za efikasnom lokomocijom u te dve sredine su bitno različiti. Pretpostavka je da razlike između vrsta u pogledu stepena koriŔćenja akvatične tj. terestrične lokomocije, može biti faktor koji doprinosi razlikama u dužinama skeletnih elemenata i različitim obrascima korelacija između elemenata ekstremiteta, oslikavajući adaptacije na različite uslove sredine i način života (viÅ”e ili manje akvatičan-terestričan)...Integration, modularity and developmental constraints are three related components of phenotypic variability. Their impacts on morphological evolution on limbs in five species of crested newts were analyzed in this thesis. Crested newts are valuable model or ganisms in studies of morphological integration and developmental constraints, especially when concern limbs. They are closely related group of species with known phylogenetic relations, and each characterized by a specific body-to-limb conformation associated with their respective ecologies. Aquatic species of newts have small, elongate bodies and small limbs while more terrestrial species are with large, stocky bodies and robust limbs. Also, as group with complex life cycle, where larval, juvenile and adult stage have different morphologies, ecol ogies and different diet and locomotor preferences, crested newts have special pl ace in studies of changes in ontogenetic trajectories. Ontogenetic niche change and transition between aquatic and terrestrial environment is connected with process of metamorphosis. Although limbs in newts do not undergo drastic chan ges in structure during that process, functional demands for high efficient loco motion in both environments are quit different. It is assumed that the differenc es between species in degree of aquatic and terrestrial locomotion may be the fa ctor which can attribute to changes in length of skeletal elements and differe nt patterns of correlations between limb elements, reflecting adaptations on diffe rent environments and life styles of analyzed species of crested newts..

    Epidemiology of hip fractures in Bulgaria : development of a country-specific FRAX model

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    Summary A retrospective population-based survey was undertaken in a region of Bulgaria to determine the incidence of hip fracture. The estimated number of hip fractures nationwide for 2015 was 9322 and is predicted to increase to 11,398 in 2050. The hip fracture rates were used to create a FRAX model. Objective To describe the epidemiology of hip fractures in Bulgaria, which was then used to develop the country-specific fracture prediction FRAXĀ® tool. Methods We carried out a retrospective population-based survey in Stara Zagora, Bulgaria, representing approximately 4.6% of the countryā€™s population. We identified hip fractures occurring in 2015, 2016 and 2017 from hospital registers and primary care sources held by the regional health insurance agency. Age- and sex-specific incidence of hip fracture and national mortality rates were incorporated into a FRAX model for Bulgaria. Fracture probabilities were compared with those from neighbouring countries having FRAX models. Results The incidence of hip fracture applied nationally suggested that the estimated number of hip fractures nationwide in persons over the age of 50 years for 2015 was 9322 and is predicted to increase to 11,398 in 2050. FRAX-based probabilities were higher in Bulgaria than those in Serbia or Romania, lower than those in Turkey and similar to those in Greece. Conclusion The FRAX model should enhance accuracy of determining fracture probability among the Bulgarian population and help guide decisions about treatment

    Long Range Hydration Effects in Electrolytic Free Suspended Black Films

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    The force law within free suspended black films made of negatively charged Aerosol-OT (AOT) with added LiCl or CsCl is studied accurately using X-ray reflectivity (ca. 1{\AA}). We find an electrolyte concentration threshold above which a substantial additional repulsion is detected in the LiCl films, up to distances of 100 {\AA}. We interpret this phenomenon as an augmentation of the Debye screening length, due to the local screening of the condensed hydrophilic counterions by the primary hydration shell.Comment: 4 pages, 4 figures, to be published Phys. Rev. Let

    Current state and prospects of development of powder metallurgy in Bulgaria

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    Characterization of a protein serine kinase from yeast plasma membrane.

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    A casein kinase activity, which copurifies with the H+-ATPase activity during isolation of plasma membranes Saccharomyces cerevisiae and during centrifugation of the solubilized membrane extract through a sucrose gradient, is separated from the Mr = 100,000 ATPase catalytic polypeptide by subsequent DEAE-cellulose chromatography. The purified casein kinase activity exhibits a low Km of 12 microM MgATP, is maximally stimulated by 6 mM free Mg2+, and is 50% inhibited by 300 microM Zn2+, by 7.5 micrograms of heparin/ml, and by 300 microM orthovanadate. It phosphorylates only seryl residues. The purified casein kinase contains two polypeptides of Mr = 45,000 and 39,000 which yield antibodies which do not cross-react to each other. The two polypeptides seem to originate from a precursor of Mr = 85,000 which is detected by both antibodies in partly purified fractions. In the absence of casein, a zinc and heparin-sensitive phosphorylation of the ATPase polypeptide is observed in partly purified ATPase fractions, and a peptide of similar mobility is phosphorylated, among others, in isolated plasma membranes. The purified ATPase activity is markedly inhibited by incubation in the presence of acid phosphatase. In agreement with a recent report that the purified active ATPase molecule is largely phosphorylated (Yanagita, Y., Abdel-Ghany, M., Raden, D., Nelson, N., and Racker, E. (1987) Proc. Natl. Acad. Sci. U. S. A. 894, 925-929) this data suggests that dephosphorylation leads to deactivation of ATPase activity
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