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Slikovna preiskava deformacije miokarda s sledenjem ultrazvočnega vzorca (ang. speckle tracking imaging-STI) je novejša metoda v ehokardiografiji, ki omogoča vpogled v mehaniko delovanja srčne mišice in se vse pogosteje uporablja pri vsakdanjem kliničnem delu. S to metodo se je uveljavil tudi nov globalni kazalec deformacije levega prekata v longitudinalni smeri (angl. global longitudinal strain-GLS), ki se je izkazal kot bolj občutljiv kazalec za odkrivanje zgodnje okvare miokarda kot klasični ehokardiografski kazalci sistolične funkcije. Kazalci deformacije imajo tako diagnostično kot prognostično vrednost pri številnih bolezenskih stanjih. Značilne spremembe, ki jih lahko zaznamo s STI pri ishemični bolezni srca so znižanje deformacije v sistoli, raztezanje miokarda v zgodnji sistoli in skrajšanje miokarda po koncu sistole. Metoda STI nam je v pomoč pri odkrivanju zgodnje okvare sistolične funkcije pri bolnikih s hipertrofijo miokarda in pri razlikovanju vzrokov hipertrofij. S STI lahko prepoznamo subklinično okvaro miokarda po kemoterapiji, zato ji dajejo evropska priporočila prednost pred klasičnimi ehokardiografskimi kazalci pri nadaljnjem kliničnem odločanju. Pri asimptomatičnih bolnikih z zmerno do hudo boleznijo srčnih zaklopk znižane vrednosti GLS kažejo na prikrito okvaro miokarda in napovedujejo večje tveganje za po-operativne zaplete. Pri bolnikih z miokarditisom s STI zaznamo znižane vrednosti segmentne deformacije in odražajo fokalno prizadetost levega prekata. Prav tako pa kazalniki deformacije miokarda tudi dobro napovedujejo uspešnost zdravljenja pri bolnikih z resinhronizacijskim spodbujevalnikom. V prispevku želimo predstaviti osnove analizo GLS po posameznih korakih, ki veljajo ne glede na vrsto ultrazvočnega aparata ali programske opreme, ter predstaviti primere uporabe STI pri posameznih bolezenskih stanjih, za katere obstaja največ dokazov klinične uporabnosti.

At each point of the geodetic network kinematic quantities are considered: normal strain, shear strain and rotation. This differs from the treatment of deformations on the basis of point movements as the traditional geodetic approach. Strain and rotation depend on the changes of geodetic datum. In the case of two different coordinate systems in each epoch, we cannot ca/cu/ate the real value of movements, strains and rotations. Despite the empirical studies of the datum invariance, we derived analytical mathematical expressions of functional dependency of strains and rotations from the relative change of datum parameters between two measurement epochs. Practical demonstration of functional dependencies has been shown in the case of the selected planar geodetic network.

Earthquake and Volcano Deformationis the first textbook to present the mechanical models of earthquake and volcanic processes, emphasizing earth-surface deformations that can be compared with observations from Global Positioning System (GPS) receivers, Interferometric Radar (InSAR), and borehole strain- and tiltmeters. Paul Segall provides the physical and mathematical fundamentals for the models used to interpret deformation measurements near active faults and volcanic centers. Segall highlights analytical methods of continuum mechanics applied to problems of active crustal deformation. Topics include elastic dislocation theory in homogeneous and layered half-spaces, crack models of faults and planar intrusions, elastic fields due to pressurized spherical and ellipsoidal magma chambers, time-dependent deformation resulting from faulting in an elastic layer overlying a viscoelastic half-space and related earthquake cycle models, poroelastic effects due to faulting and magma chamber inflation in a fluid-saturated crust, and the effects of gravity on deformation. He also explains changes in the gravitational field due to faulting and magmatic intrusion, effects of irregular surface topography and earth curvature, and modern concepts in rate- and state-dependent fault friction. This textbook presents sample calculations and compares model predictions against field data from seismic and volcanic settings from around the world. Earthquake and Volcano Deformationrequires working knowledge of stress and strain, and advanced calculus. It is appropriate for advanced undergraduates and graduate students in geophysics, geology, and engineering. Professors: A supplementary Instructor's Manual is available for this book. It is restricted to teachers using the text in courses. For information on how to obtain a copy, refer to: http://press.princeton.edu/class_use/solutions.html

In the second half of the previous century, analysis of deformations became a highly interesting subject of research and practical application in industry. The presented approach was developed in British Columbia, Canada, for the determination of potential deformations on several dams and landslide areas. Original measurements were obtained via standard surveying observation of distances and directions for horizontal positioning, and elevation differences for vertical positioning. GPS vectors were added some years later. The geodetic measurements of several epochs were adjusted with the parametric model of the method of least squares with minimum datum constraints. The deformation analysis was made with the successive application of the Helmert transformation.

High-technology industries using plastic deformation demand soundly-based economical decisions in manufacturing design and product testing, and the unified constitutive laws of plastic deformation give researchers aguideline to use in making these decisions.

Uzimajući u obzir redoslijed otkopavanja, svrha je ovoga članka istražiti utjecaj otkopavanja bez sekundarnih stupova, primjenjujući piramidalni niz otkopavanja od centra prema van, na stabilnost transportnih hodnika, na količinu neotkopane nestabilne rude u komorama i potrebnu količinu materijala za zapunjavanje. Za procjenu stabilnosti transportnih hodnika te procjenu količine neotkopane i nestabilne rude uslijed rudarskih aktivnosti primijenjena je širina plastične zone deformacija unutar stijenske mase oko transportnih hodnika i neotkopanih komora. Rezultati su prikazani i raspravljeni u smislu veličine zone sloma, količine nestabilne sirovine u neotkopanim blokovima i količine potrebnoga materijala za zapunjavanje ovisno o fazi iskopavanja. Ispitivanjima je ustanovljeno da se stabilnost transportnih hodnika naglo smanjuje. Do sloma svoda transportnoga hodnika dolazi u ranoj fazi (nakon 3. koraka otkopavanja). U svodu hodnika, lijevome zidu, podu i desnome zidu, zone sloma izmjerene su na 1,55 m (korak 3), 2,28 m (korak 4), 2,57 m (korak 5) i 1,88 m (korak 5). Nakon 4. koraka iskopavanja, izračunano je ukupno 905 m3 neotkopane nestabilne rude (4100 tona). Pri tome je u 5. Koraku otkopavanja potrebno ukupno 1500 m3 (30 tona) materijala za zapunjavanje i ojačavanje komora.

Izloženi su mogući izvori naprezanja i deformacija u kamenu. Sugeriran je raspon porijekla naprezanja koja utječu na otpornost kamena, od onih koja pripadaju prirodnim uvjetima u ležištu do onih koja su rezultat primijenjenih tehnologija u eksploataciji, preradi i oblaganju uključivši okoliš s prirodnim i tehnogenim činiocima. O pojavama na kamenu obrađenom najnovijim tehnologijama ne mogu se izložiti neka saznanja zbog prekratkog vremena kroz koje je ugrađeni kamen bio izložen utjecaju prirodnih i tehnogenih činilaca.