393,938 research outputs found
Corso di lingua hindi
No full textCorso completo di lingua hindi, con testi illustrativi, sezione grammaticale, esercizi, glossario e due CD per esercizi orali. G. Milanetti è autore del piano dell'opera e delle sezioni denominate 'Grammatica'; S.T. Gupta è autrice delle sezioni denominate 'Testo', 'Esercizi' e 'Glossario'
Nivelen luu-rustorajapinnan mikrometritason kudosmuutoksien tutkiminen nivelrikon eri vaiheissa
No full textAbstractOsteoarthritis (OA) is the most common joint disease that causes disability in the adult population. While the etiology and pathogenesis of OA remain unclear, it is now commonly accepted that the entire joint is affected by OA. The deep zone of hyaline articular cartilage, calcified cartilage, and cortical subchondral bone plate form the osteochondral junction that is specially adapted to transferring loads during weight-bearing and joint motion. Although the OA-related changes in articular cartilage and subchondral trabecular bone have been extensively studied, the changes in the osteochondral junction, especially in the calcified cartilage, remain under explored.Calcified cartilage is a relatively thin tissue layer and has a similar mineral phase to the underlying bone. Hence, it is a major challenge to quantitively study calcified cartilage separately from the whole osteochondral junction, due to the limitations in spatial resolution and the contrast of current microscopic imaging modalities. Therefore, this doctoral dissertation aims to study the biochemical composition, mineral crystal structure, micromechanical and structural properties of calcified cartilage, and the subchondral bone plate in healthy and osteoarthritic knee joints in vitro.Raman microspectroscopy was used to investigate biochemical composition from unfixed and fully hydrated human osteochondral specimens. State-of-the-art micro-focus small-angle X-ray scattering (μSAXS) measurements were performed to map the mineral crystal thickness across the junction. Finally, a bovine patella model was utilized to explore the micromechanical changes in the junction as a function of degeneration and associate these changes with site-specific microstructure.Results show that calcified cartilage had a higher degree of mineralization, with thicker mineral crystals having greater stoichiometric perfection in a proteoglycan-rich matrix than underlying bone. The alterations in the degree of mineralization, type-B carbonate substitutions, mineral crystal thickness, tissue stiffness, and microstructure in both calcified cartilage and subchondral bone plate were observed during OA development. Some of these changes were found to occur at the very early stages of OA. In conclusion, this study shows that both mineralized tissues at the osteochondral junction undergo marked alterations during the evolution of OA, contributing to our current understanding of OA.Original papersOriginal papers are not included in the electronic version of the dissertation.Das Gupta, S., Finnilä, M. A. J., Karhula, S. S., Kauppinen, S., Joukainen, A., Kröger, H., Korhonen, R. K., Thambyah, A., Rieppo, L., & Saarakkala, S. (2020). Raman microspectroscopic analysis of the tissue-specific composition of the human osteochondral junction in osteoarthritis: A pilot study. Acta Biomaterialia, 106, 145–155. https://doi.org/10.1016/j.actbio.2020.02.020Self-archived versionFinnilä, M. A. J., Das Gupta, S., Turunen, M. J., Kestilä, I., Turkiewicz, A., Lutz-Bueno, V., Folkesson, E., Holler, M., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Guizar-Sicairos, M., Saarakkala, S., & Englund, M. (2021). Mineral crystal thickness in calcified cartilage and subchondral bone in healthy and osteoarthritic knees. BioRxiv. https://doi.org/10.1101/2021.06.15.448181Das Gupta, S., Finnilä, M. A. J., Rieppo, L., Turunen, M. J., Kestilä, I., Lutz-Bueno, V., Folkesson, E., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Turkiewicz, A., Englund, M., & Saarakkala, S. (2021). Mineral composition of calcified cartilage and subchondral bone plate in humans with and without knee osteoarthritis. Manuscript in preparation.Das Gupta, S., Workman, J., Finnilä, M. A. J., Saarakkala, S., & Thambyah, A. (2022). Subchondral bone plate thickness is associated with micromechanical and microstructural changes in the bovine patella osteochondral junction with different levels of cartilage degeneration. Journal of the Mechanical Behavior of Biomedical Materials, 129, 105158. https://doi.org/10.1016/j.jmbbm.2022.105158Self-archived versionTiivistelmäNivelrikko on aikuisväestön yleisin invalidoiva nivelsairaus. Nivelrikon tarkkaa syntytapaa ei edelleenkään tiedetä, mutta nykyisin on yleisesti hyväksytty, että nivelrikko vaikuttaa kaikkiin nivelen kudoksiin. Nivelessä sijaitseva luu-rustorajapinta muodostuu hyaliiniruston pohjakerroksen, kalkkeutuneen ruston ja rustonalaisen luun yhdistelmästä. Luu-rustorajapinnan rooli on välittää mekaanista kuormitusta rustosta luuhun nivelen liikkuessa. Nivelruston ja sen alaisen luun kudosmuutoksia nivelrikon eri vaiheissa on tutkittu laajasti, mutta luu-rustorajapinnan — erityisesti kalkkeutuneen ruston — kudosmuutoksia nivelrikon aikana on tutkittu vain vähän.Kalkkeutunut rusto on ohut kudoskerros, jossa on myös mineraalifaasi samoin kuin alla olevassa luukudoksessa. Tämä tekee kalkkeutuneen ruston kvantitatiivisesta tutkimisesta hankalaa, koska luun ja kalkkeutuneen ruston erottaminen on vaikeaa mikroskooppisten kuvantamismenetelmien rajoittuneen kontrastin ja erotuskyvyn vuoksi. Tässä väitöskirjassa tutkittiin nivelrikkoisen ja terveen kalkkeutuneen ruston biokemiallista koostumusta, mikrorakennetta sekä mikromekaanisia ominaisuuksia.Ihmisestä saatuja tuoreita ja käsittelemättömiä luu-rustonäytteitä tutkittiin aluksi Raman-mikroskopialla, jonka perusteella kartoitettiin niiden biokemiallista koostumusta eri kohdissa kudosta. Mineraalikristalleja analysoitiin pienkulmaröntgensironnan avulla, jolla pystyttiin kartoittamaan kristallien paksuutta koko luu-rustorajapinnan alueelta. Tutkimuksessa käytettiin myös naudan polvilumpiosta otettuja näytteitä, joiden avulla tutkittiin luu-rustorajapinnan mikromekaanisia muutoksia nivelrikon eri kehitysvaiheissa. Lisäksi tutkittiin mikromekaanisten muutoksien ja mikrorakenteen muutoksien välistä yhteyttä toisiinsa.Tulokset osoittavat, että kalkkeutuneessa rustossa on luuhun verrattuna korkeampi mineralisoitumisen aste, paksummat ja stoikiometrisesti täydellisemmät mineraalikristallit, sekä suurempi proteoglykaanipitoisuus. Lisäksi tutkimuksessa havaittiin selkeitä muutoksia mineralisaation määrässä, tyypin B karbonaattisubstituutiossa, mineraalikristallien paksuudessa, kudoksen jäykkyydessä sekä mikrorakenteessa nivelrikon kehittyessä. Osa muutoksista havaittiin hyvin varhaisessa nivelrikon kehitysvaiheessa. Tässä väitöskirjassa saatiin tärkeää uutta tietoa siitä, että luu-rustorajapinnnassa tapahtuu merkittäviä muutoksia nivelrikon kehittyessä. Tämä lisää nykyistä tietämystämme nivelrikon etiologiasta.OsajulkaisutOsajulkaisut eivät sisälly väitöskirjan elektroniseen versioon.Das Gupta, S., Finnilä, M. A. J., Karhula, S. S., Kauppinen, S., Joukainen, A., Kröger, H., Korhonen, R. K., Thambyah, A., Rieppo, L., & Saarakkala, S. (2020). Raman microspectroscopic analysis of the tissue-specific composition of the human osteochondral junction in osteoarthritis: A pilot study. Acta Biomaterialia, 106, 145–155. https://doi.org/10.1016/j.actbio.2020.02.020Rinnakkaistallennettu versioFinnilä, M. A. J., Das Gupta, S., Turunen, M. J., Kestilä, I., Turkiewicz, A., Lutz-Bueno, V., Folkesson, E., Holler, M., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Guizar-Sicairos, M., Saarakkala, S., & Englund, M. (2021). Mineral crystal thickness in calcified cartilage and subchondral bone in healthy and osteoarthritic knees. BioRxiv. https://doi.org/10.1101/2021.06.15.448181Das Gupta, S., Finnilä, M. A. J., Rieppo, L., Turunen, M. J., Kestilä, I., Lutz-Bueno, V., Folkesson, E., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Turkiewicz, A., Englund, M., & Saarakkala, S. (2021). Mineral composition of calcified cartilage and subchondral bone plate in humans with and without knee osteoarthritis. Manuscript in preparation.Das Gupta, S., Workman, J., Finnilä, M. A. J., Saarakkala, S., & Thambyah, A. (2022). Subchondral bone plate thickness is associated with micromechanical and microstructural changes in the bovine patella osteochondral junction with different levels of cartilage degeneration. Journal of the Mechanical Behavior of Biomedical Materials, 129, 105158. https://doi.org/10.1016/j.jmbbm.2022.105158Rinnakkaistallennettu versioAcademic dissertation to be presented with the assent of the Doctoral Programme Committee of Health and Biosciences of the University of Oulu for public defence in the Markku Larmas auditorium (H1091) in Dentopolis, on 12 August 2022, at 12 noonAbstract
Osteoarthritis (OA) is the most common joint disease that causes disability in the adult population. While the etiology and pathogenesis of OA remain unclear, it is now commonly accepted that the entire joint is affected by OA. The deep zone of hyaline articular cartilage, calcified cartilage, and cortical subchondral bone plate form the osteochondral junction that is specially adapted to transferring loads during weight-bearing and joint motion. Although the OA-related changes in articular cartilage and subchondral trabecular bone have been extensively studied, the changes in the osteochondral junction, especially in the calcified cartilage, remain under explored.
Calcified cartilage is a relatively thin tissue layer and has a similar mineral phase to the underlying bone. Hence, it is a major challenge to quantitively study calcified cartilage separately from the whole osteochondral junction, due to the limitations in spatial resolution and the contrast of current microscopic imaging modalities. Therefore, this doctoral dissertation aims to study the biochemical composition, mineral crystal structure, micromechanical and structural properties of calcified cartilage, and the subchondral bone plate in healthy and osteoarthritic knee joints in vitro.
Raman microspectroscopy was used to investigate biochemical composition from unfixed and fully hydrated human osteochondral specimens. State-of-the-art micro-focus small-angle X-ray scattering (μSAXS) measurements were performed to map the mineral crystal thickness across the junction. Finally, a bovine patella model was utilized to explore the micromechanical changes in the junction as a function of degeneration and associate these changes with site-specific microstructure.
Results show that calcified cartilage had a higher degree of mineralization, with thicker mineral crystals having greater stoichiometric perfection in a proteoglycan-rich matrix than underlying bone. The alterations in the degree of mineralization, type-B carbonate substitutions, mineral crystal thickness, tissue stiffness, and microstructure in both calcified cartilage and subchondral bone plate were observed during OA development. Some of these changes were found to occur at the very early stages of OA. In conclusion, this study shows that both mineralized tissues at the osteochondral junction undergo marked alterations during the evolution of OA, contributing to our current understanding of OA.Tiivistelmä
Nivelrikko on aikuisväestön yleisin invalidoiva nivelsairaus. Nivelrikon tarkkaa syntytapaa ei edelleenkään tiedetä, mutta nykyisin on yleisesti hyväksytty, että nivelrikko vaikuttaa kaikkiin nivelen kudoksiin. Nivelessä sijaitseva luu-rustorajapinta muodostuu hyaliiniruston pohjakerroksen, kalkkeutuneen ruston ja rustonalaisen luun yhdistelmästä. Luu-rustorajapinnan rooli on välittää mekaanista kuormitusta rustosta luuhun nivelen liikkuessa. Nivelruston ja sen alaisen luun kudosmuutoksia nivelrikon eri vaiheissa on tutkittu laajasti, mutta luu-rustorajapinnan — erityisesti kalkkeutuneen ruston — kudosmuutoksia nivelrikon aikana on tutkittu vain vähän.
Kalkkeutunut rusto on ohut kudoskerros, jossa on myös mineraalifaasi samoin kuin alla olevassa luukudoksessa. Tämä tekee kalkkeutuneen ruston kvantitatiivisesta tutkimisesta hankalaa, koska luun ja kalkkeutuneen ruston erottaminen on vaikeaa mikroskooppisten kuvantamismenetelmien rajoittuneen kontrastin ja erotuskyvyn vuoksi. Tässä väitöskirjassa tutkittiin nivelrikkoisen ja terveen kalkkeutuneen ruston biokemiallista koostumusta, mikrorakennetta sekä mikromekaanisia ominaisuuksia.
Ihmisestä saatuja tuoreita ja käsittelemättömiä luu-rustonäytteitä tutkittiin aluksi Raman-mikroskopialla, jonka perusteella kartoitettiin niiden biokemiallista koostumusta eri kohdissa kudosta. Mineraalikristalleja analysoitiin pienkulmaröntgensironnan avulla, jolla pystyttiin kartoittamaan kristallien paksuutta koko luu-rustorajapinnan alueelta. Tutkimuksessa käytettiin myös naudan polvilumpiosta otettuja näytteitä, joiden avulla tutkittiin luu-rustorajapinnan mikromekaanisia muutoksia nivelrikon eri kehitysvaiheissa. Lisäksi tutkittiin mikromekaanisten muutoksien ja mikrorakenteen muutoksien välistä yhteyttä toisiinsa.
Tulokset osoittavat, että kalkkeutuneessa rustossa on luuhun verrattuna korkeampi mineralisoitumisen aste, paksummat ja stoikiometrisesti täydellisemmät mineraalikristallit, sekä suurempi proteoglykaanipitoisuus. Lisäksi tutkimuksessa havaittiin selkeitä muutoksia mineralisaation määrässä, tyypin B karbonaattisubstituutiossa, mineraalikristallien paksuudessa, kudoksen jäykkyydessä sekä mikrorakenteessa nivelrikon kehittyessä. Osa muutoksista havaittiin hyvin varhaisessa nivelrikon kehitysvaiheessa. Tässä väitöskirjassa saatiin tärkeää uutta tietoa siitä, että luu-rustorajapinnnassa tapahtuu merkittäviä muutoksia nivelrikon kehittyessä. Tämä lisää nykyistä tietämystämme nivelrikon etiologiasta
One-dimensional lattice of oscillators coupled through power-law interactions: Continuum limit and dynamics of spatial Fourier modes
No full textWe study synchronization in a system of phase-only oscillators residing on the sites of a one-dimensional periodic lattice. The oscillators interact with a strength that decays as a power law of the separation along the lattice length and is normalized by a size-dependent constant. The exponent ? of the power law is taken in the range 0??<1. The oscillator frequency distribution is symmetric about its mean (taken to be zero) and is nonincreasing on [0,?). In the continuum limit, the local density of oscillators evolves in time following the continuity equation that expresses the conservation of the number of oscillators of each frequency under the dynamics. This equation admits as a stationary solution the unsynchronized state uniform both in phase and over the space of the lattice. We perform a linear stability analysis of this state to show that when it is unstable, different spatial Fourier modes of fluctuations have different stability thresholds beyond which they grow exponentially in time with rates that depend on the Fourier modes. However, numerical simulations show that at long times all the nonzero Fourier modes decay in time, while only the zero Fourier mode (i.e., the “mean-field” mode) grows in time, thereby dominating the instability process and driving the system to a synchronized state. Our theoretical analysis is supported by extensive numerical simulations.Delft Center for Systems and ControlMechanical, Maritime and Materials Engineerin
The Gupta-Belnap Systems S# and S* are Not Axiomatisable
No full textAnil Gupta and Nuel Belnap's "The Revision Theory of Truth" presents revision theoretic systems of circular definitions. Part I of the present paper shows that the revision theories S# and S* axiomatisable. Part II refines this result. Among other things, Part II shows that there is a strong relationship between revision theories and the theory of inductive definitions. This relationship is exploited to show that S# and S* (and all "plausible" revision theories of circular definitions) are of complexity at least "P" 1/2
S. P. Gupta, Planning and Development in India
No full textÉtienne Gilbert. S. P. Gupta, Planning and Development in India. In: Tiers-Monde, tome 30, n°119, 1989. L'Inde : libéralisation et enjeux sociaux, sous la direction de Bernadette Madeuf et Philippe Cadène. pp. 705-706
Data Supporting “Studying mate preferences using inertial measurement units: A validation study with treefrogs”
No full textThe 8 data and code files in this archive accompany the manuscript "Studying mate preferences using inertial measurement units: A validation study with treefrogs"Investigations of mate choice continue to address fundamental questions about the
mechanisms and evolution of animal behaviour. A common behavioural assay used to study
acoustically guided mate choice with playback experiments is phonotaxis, a typically robust
response in which a chooser approaches a sound source broadcasting acoustic signals, such
as courtship songs or mating calls. Robust empirical studies of phonotaxis often require
substantial laboratory facilities, such as a dedicated and sound-treated room or enclosure, in
which the acoustic environment is controlled and in which animals are freely able to move
about. The financial and space resources required to outfit a research laboratory to investigate
phonotaxis may be sufficiently prohibitive such that some researchers are excluded from
undertaking bioacoustic behavioural research. Here, we validate a new device designed to
measure animal movements related to phonotaxis behaviour using an inertial measurement unit
(IMU). The device is small and portable; it can be constructed for less than $300 US dollars; and
the build instructions and code for operation are freely available (Gupta et al., 2020, HardwareX,
8, e00116). In a series of four experiments with treefrogs, we demonstrate using the device that
an IMU-based approach to measuring animal movement can replicate a broad range of findings
from traditional phonotaxis experiments on species recognition and sexual selection. We
conclude by discussing several possible uses for IMU-based measurements of phonotaxis.National Science FoundationGupta, Saumya; Bee, Mark A. (2023). Data Supporting “Studying mate preferences using inertial measurement units: A validation study with treefrogs”. Retrieved from the University Digital Conservancy, https://doi.org/10.13020/fzk6-1q04
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