127 research outputs found
Medical photography
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 āphotographyā comes from greek (āphotosā - light and āgraphoā - write) and means ālight-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 ādigitalā 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)
Integracija, modularnost i razvojna ograniÄenja 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 ograniÄenja, 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 akvatiÄnoj/terestriÄnoj sredini. AkvatiÄne vrste se odlikuju izduženim telom i kratkim nogama, dok su vrste sa viÅ”e terestriÄnim životnim stilom snažnije i robusnije graÄe sa dugim nogama. TakoÄe, kao grupa sa složenim životnim ciklusom, gde larveni, juvenilni i adultni stupanj imaju razliÄite morfologije, ekoloÅ”ke sredine i preference, naÄine ishrane i lokomocije, veliki krestasti mrmoljci imaju posebno mesto u izuÄavanju ontogenetskih putanja tokom razviÄa. Ontogenetska promena niÅ”e i tranzicija izmeÄu akvatiÄne i terestriÄne sredine je povezana sa procesom metamorfoze. Iako ekstremiteti mrmoljaka ne prolaze kroz drastiÄne promene strukture tokom tog procesa, funkcionalni zahtevi za efikasnom lokomocijom u te dve sredine su bitno razliÄiti. Pretpostavka je da razlike izmeÄu vrsta u pogledu stepena koriÅ”Äenja akvatiÄne tj. terestriÄne lokomocije, može biti faktor koji doprinosi razlikama u dužinama skeletnih elemenata i razliÄitim obrascima korelacija izmeÄu elemenata ekstremiteta, oslikavajuÄi adaptacije na razliÄite uslove sredine i naÄin života (viÅ”e ili manje akvatiÄan-terestriÄan)...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..
Recommended from our members
Identification and Perceived Value of Ecosystem Services of Urban Green Areas. Case Study: KameniÄki Park in Novi Sad, Serbia
Urban parks, as one of the most significant urban green areas (UGA), bring many direct or indirect benefits, including but not limited to ecosystem services (ES) (Mexia et al. 2018). These services are often generalized, unquantified and poorly supported by empirical evidence and their negative consequences ā disservices are rarely mentioned (Roman et al., 2021; Pataki et al., 2011). In order to improve planning, design and management of UGA that can increase their environmental benefits (Xie et al. 2019), better understanding and additional field research of ES and disservices is required. As a result of a survey of employees of the Institute for Nature Conservation of Vojvodina Province that manages the park and on-site users, this study represents a research of the perceived value of generated ES on the example of KameniÄki park in Novi Sad, as there are no studies on the actual value of those ES. After identifying major ES, the employees and users evaluated them by their perception on a scale of 1 ā the ES is well provided, 2 ā service is provided but can be enhanced and 3 ā the service is not provided, but has potential. Employees mainly emphasized regulation and supporting services (regulation of air quality, noise reduction, wind protection, maintaining biodiversity), but also cultural services (educational role, recreation and enjoying nature, spiritual peace and prosperity). Users opted mainly for cultural services (recreation and enjoying nature and inspiration for culture, art and design), but also for supporting services like maintaining biodiversity. The specific location, valuable natural and cultural-historical characteristics of KameniÄki park contribute to the provision of numerous ES, but also offer the opportunity to develop additional ones that are currently not represented or are not sufficiently provided. The opinions and needs of stakeholders and users regarding ES can be a guideline in planning in accordance with the ES, which is a step to sustainable cities. Quantifying the degree to which various ES are related to plant diversity and structure would provide evidence of the ability to manipulate designed ecosystems to maximize the benefits they provide to urban landscapes (Nighswander et al. 2021)
Epidemiology of hip fractures in Bulgaria : development of a country-specific FRAX model
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 countryās 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
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
Characterization of a protein serine kinase from yeast plasma membrane.
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
- ā¦