1,333 research outputs found

    Study of the optical power of nanophotonic soft contact lenses based on poly (2-hydroxyethyl methacrylate) and fullerene

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    U radu su predstavljeni rezultati komparativnih istraživanja optičke snage mekih kontaktnih sočiva (MKS) sa različitim tehnikama mjerenja koje se koriste pri finalnoj obradi kontaktnih sočiva. Tri vrste nanofotoničnih mekih kontaktnih sočiva su napravljene od standardnog polimacon materijala (Soleko SP38TM) sa inkorporiranim fulerenom C60, fulerolom C60(OH)24 i fuleren-metformin-hidroksilatom C60(OH)12(OC4N5H10)12. Za potrebe karakterizacije materijala za potencijalnu primjenu kod mekih kontaktnih sočiva, mjerena su optička svojstva mekih kontaktnih sočiva Rotleks i Nidek uređajem. Sa Rotleks uređajem dobijeni su sledeći optički rezultati: optička snaga i mapa defekata, a sa Nidek uređajem: optička snaga, snaga cilindra i ugao cilindra. Dobijene vrijednosti optičke snage i mape defekata pokazali su da optička snaga sintetisanih nanofotoničnih mekih kontaktnih sočiva je identična nominalnoj vrijednosti, dok to nije bio slučaj za standardna meka kontaktna sočiva. Takođe, kvalitet nanofotoničnih mekih kontaktnih sočiva je bolji nego kod standardnih mekih kontaktnih sočiva. Iz prikazanog se može zaključiti da je moguće sintetisati nova nanofotonična meka kontaktna sočiva željenih optičkih karakteristika, što otvara mogućnosti za njihovu primjenu u ovoj oblasti.In this paper results of comparative study of the optical power of soft contact lenses (SCL) made of standard material for SCL and nanophotonic materials with different measurement techniques used for the final contact lens controllers are presented. Three types of nanophotonic soft contact lenses were made of standard polymacon material (Soleko SP38 TM) incorporated with fullerene C 60 , fullerol C 60 (OH) 24 and fullerene metformin hydroxylate C 60 (OH) 12 (OC 4 N 5 H 10) 12. For the purposes of material characterization for potential application as soft contact lenses, the optical properties of the soft contact lenses were measured by Rotlex and Nidek device. With Rotlex device the following optical results were obtained: optical power and map of defects, while with the Nidek device: optical power, cylinder power and cylinder axis. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is same to the nominal value, while this was not the case for the standard soft contact lens. Also, the quality of the nanophotonic soft contact lens is better than the standard one. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field

    Characterization of fullerenes thin film on glasses by UV/VIS/NIR and opto-magnetic imaging spectroscopy

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    UV/VIS ispitivanje stakala za naočare je deo standardne procedure. Razlog za to jeste da se osigura UV zaštita oka, kao i karakterizacija transparentnosti materijala. Međutim, mi smo proširiti ovo istraživanje u IR domenu iz razloga što kvalitet stakala ne zavisi samo od UV zaštite i njihove transparentnosti, već takođe i od komplementarnosti i kompatibilnosti oka sa optičkim pomagalom. Izvršena je karakterizacija osnovnog materijala za naočare pomoću UV/VIS/NIR i nove metode opto-magnetne imidžing spektroskopije. Nakon toga osnovni materijal dopiran je fulerenom, i izvršena je karakterizacija primenom istih metoda. Rezultati su predstavljeni i diskutovani.UV/VIS spectroscopic characterization of glasses is a part of the standard procedure. The reasons to do it is to ensure UV eye protection and characterization of material transparency. However, we extend this research to IR domain because the quality of glasses depend not only on UV protection and their transparency but on complementarities and compatibility of eye vision with optical device, also. We characterized basic material of glasses by UV/VIS/NIR and novel method Opto-magnetic Imaging Spectroscopy (OMIS). Then we doped basic material with fullerenes, and characterized them using the same procedure. Results are presented and discussed

    Collective cell durotaxis emerges from long-range intercellular force transmission

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    The ability of cells to follow gradients of extracellular matrix stiffness—durotaxis—has been implicated in development, fibrosis, and cancer. Here, we found multicellular clusters that exhibited durotaxis even if isolated constituent cells did not. This emergent mode of directed collective cell migration applied to a variety of epithelial cell types, required the action of myosin motors, and originated from supracellular transmission of contractile physical forces. To explain the observed phenomenology, we developed a generalized clutch model in which local stick-slip dynamics of cell-matrix adhesions was integrated to the tissue level through cell-cell junctions. Collective durotaxis is far more efficient than single-cell durotaxis; it thus emerges as a robust mechanism to direct cell migration during development, wound healing, and collective cancer cell invasion.Peer ReviewedPostprint (author's final draft

    Characterization of fullerenes thin film on glasses by UV/VIS/NIR and opto-magnetic imaging spectroscopy

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    UV/VIS ispitivanje stakala za naočare je deo standardne procedure. Razlog za to jeste da se osigura UV zaštita oka, kao i karakterizacija transparentnosti materijala. Međutim, mi smo proširiti ovo istraživanje u IR domenu iz razloga što kvalitet stakala ne zavisi samo od UV zaštite i njihove transparentnosti, već takođe i od komplementarnosti i kompatibilnosti oka sa optičkim pomagalom. Izvršena je karakterizacija osnovnog materijala za naočare pomoću UV/VIS/NIR i nove metode opto-magnetne imidžing spektroskopije. Nakon toga osnovni materijal dopiran je fulerenom, i izvršena je karakterizacija primenom istih metoda. Rezultati su predstavljeni i diskutovani.UV/VIS spectroscopic characterization of glasses is a part of the standard procedure. The reasons to do it is to ensure UV eye protection and characterization of material transparency. However, we extend this research to IR domain because the quality of glasses depend not only on UV protection and their transparency but on complementarities and compatibility of eye vision with optical device, also. We characterized basic material of glasses by UV/VIS/NIR and novel method Opto-magnetic Imaging Spectroscopy (OMIS). Then we doped basic material with fullerenes, and characterized them using the same procedure. Results are presented and discussed

    Ispitivanje uticaja nanofotoničnih tvrdih gaspropusnih kontaktnih sočiva na fiziološki rastvor akvafotomikom i opto-magnetnom imidžing spektroskopijom

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    Contact lenses represent biomaterials whose main purpose is to correct the specific refractive anomaly of the eye. Since the visible light on its way to the perceptive part of the eye has to pass through the contact lens, the characteristics of the materials can significantly modify it. Biocompatibility of the lens surface is one of the most important issues in achieving contact lens wear without problems. We have developed new nanophotonic contact lens materials by adding nanoparticles of fullerene and their derivatives into standard PMMA RGP material. The aim of our investigation was to compare the influences of these materials on saline which is similar to tear film. We used NIR spectroscopy based on 12 vibration modes, called Aquaphotomics and Opto-magnetic imaging (OMI) spectroscopy as methods for characterizing the samples. The acquired spectrums were commented and compared with the standard contact lens material, which was analyzed by the same method.Kontaktna sočiva predstavljaju biomaterijale čija je glavna svrha ispravljanje specifičnih refraktivnih anomalija oka. S obzirom da vidljiva svetlost na svom putu do perceptivnog dela oka mora da prođe kroz kontaktno sočivo, karakteristike materijala mogu značajno da je izmene. Biokompatibilnost površine sočiva je jedno od najvažnijih pitanja u postizanju nošenja kontaktnih sočiva bez problema. Razvijeni su novi nanofotonični materijali za kontaktna sočiva dodavanjem nanočestica fulerena i njihovih derivata u standardni PMMA materijal za tvrda gas propusna kontaktna sočiva. Cilj našeg istraživanja je bilo poređenje uticaja ovih materijala na fiziološki rastvor koji je sličan suznom filmu. Za karakterizaciju uzoraka koristili smo blisku infracrvenu spektroskopiju zasnovanu na 12 vibracionih modova, poznatiju kao Akvafotomika. Dobijeni spektri su komentarisani i upoređeni sa standardnim materijalom za kontaktna sočiva, koji je analiziran istom metodom

    The effects of defensive style and final game outcome on the external training load of professional basketball players

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    [EN] This study aimed to analyse the influence of different contextual factors (i.e., defensive style and game outcome) on basketball players’ external load during games-based drills using ultrawideband (UWB) technology. Fourteen male professional basketball players belonging to an elite reserve Spanish club (ACB) participated in this study. The games-based drills consisted of one bout of 10 min played 5vs5 in which players were instructed to use man-to-man defence (MMD) and/or zone defence (ZD). In addition, the final game outcome (i.e., winning or losing) of the game-based drill was registered. External load variables per minute were recorded: total distance covered, distance covered in different speed zones, distance covered while accelerating and decelerating, maximum speed, steps, jumps and player load. A two-way ANOVA with the Tukey post hoc test was used to assess the impact of defensive style and final game outcome and the interaction of both factors on the external load encountered by basketball players. No meaningful differences (unclear) were found in the external loads between playing with MMD and with ZD and between winning and losing teams except for greater distance at high-speed running (18.0–24.0 km·h-1) in winning teams (p < 0.05, ES = 0.68, moderate). A significant interaction between defensive style and final game outcome was found for high decelerations (> -2 m·s-2) (p = 0.041; ES = 0.70) and jumps (p = 0.037; ES = 0.68). These results could potentially help coaching staff in prescribing an appropriate workload during basketball-specific gamebased drills, and ultimately enhance the match performance.The project leading to these results has received funding from “La Caixa” Foundation (ID 100010434) and La Caja de Burgos, under agreement LCF/PR/PR18/51130008Fondo Europeo de Desarrollo Regional (FEDER)] (NARPAS_MM) [SPGC201800X098742CV0]

    Petrographic-Mineralogical Characterization of Archaeological Materials from “Casa di Diana” Mithraeum Sited in the Open Museum of Ostia Antica

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    Mithraea, religious Roman buildings, are very common in Italian archeological sites. There are sixteen in Ostia Antica (Rome, Italy)The poor state of conservation, due to the intrinsic environmental conditions, characterized them: they consist of open-air museums and caves simultaneously. These places of worship are characterized by the presence of heterogeneous materials, such as wall building materials (bricks and mortars) and others used for furnishings and fittings. This increases the risk of accelerated damage because the materials ‘rheology is different. Here, a full petrographic-mineralogical characterization with polarized light microscopy (PLM), X-ray diffraction (XRD), scanning electron microscope with energy dispersive X-ray (SEM-EDS) and isotopic analysis (δ13C, δ18O) is carried out on materials like travertine, marble, pumice, ceramic, and wall-building materials in “Casa di Diana” Mithraeum (Ostia Antica). Their characterization gives provenance information as well as conservation and restoration purposes. The prevalence of siliciclastic or carbonate components discriminates between red and yellow bricks, as well as different textures and minerals in the aggregate of the red ones. The mortars are typically pozzolanic, and the aggregate is mostly made up of black and red pozzolanic clasts. In the altar, apse, and aedicule, which constitute the principal place of the Mithraeum, a variety of materials used for the ornamental purpose are represented by pumices, travertine, marble, and limestone. The altar material, catalogued as marble, resulted in being a limestone coated with a white pigment.This work has been partially supported by the DEMORA (Grant No. PID2020-113391GB-I00) projects funded by the Spanish Agency for Research AEI (MINEICO/FEDER-UE). The authors wish to acknowledge professional support of the Interdisciplinary Thematic Platform from CSIC Open Heritage: Research and Society (PTI-PAIS)

    a study in youth male soccer players exposed to Covid-19 lockdown

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    The aim of this study is to examine how physical performance has changed after 15 weeks (109 days) long-term absence of organized training in youth soccer players imposed by the stay at home orders. A total of sixty-eight young male soccer players from different age categories (U15, U16, U17 and U19) voluntarily participated in the prospective cohort study. Body fat percentage (BF%), counter-movement jump (CMJ), 30 m sprint, change-of-direction (COD) and yo-yo intermittent recovery test level-1 (YYIRTL-1) were evaluated twice (before and after the detraining period). Subsequently, 2 × 2 repeated measures ANOVA was used to investigate group and time differences in repeated measurements. A significance level of p < 0.05 was implemented. CV and SWC values were calculated to test the reliability of the tests performed at different times. Statistical analysis was performed using the IBM SPSS statistics software (v.25, IBM, New York, NY, USA). Significant increments in BF%, 30 m sprint, and COD (left and right), and also significant decrements in CMJ and YYIRTL-1, were found after the detraining period. A long-term detraining period due to the stay at home orders has a detrimental effect on body composition, neuromuscular performances, and aerobic capacity in youth soccer players.9E1A-F9DD-3EB8 | Filipe Manuel ClementeN/

    Evaluacion tecnica y economica para produccion de hortiplantines en una agroindustria

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    129 p.Las limitaciones medioambientales obligan a disminuir el uso de bromuro de metilo. Esta limitación hace que algunos procesos productivos se tornen imposibles de realizar. El proceso de producción de plantines de tomate para uso industrial y en formato raíz desnuda, se ha convertido en uno de los principales damnificados del Protocolo de Montreal, que compromete a Chile a congelar y llevar a cero gradualmente el consumo de este tóxico gas. Como consecuencia, una agroindustria líder en volumen de producción de pastas de tomate, ha decidido realizar un estudio de factibilidad, para instalar un vivero productor de plántulas, materia prima, para la fabricación de pasta de tomate. Se busca con este proyecto reemplazar la tecnología existente y proporcionar una solución al abastecimiento. Se realiza un estudio de la situación actual, encontrando que la Empresa, produce cerca 4.000ha anuales de tomate. Las plantas utilizadas para este efecto son en un 50% producidas en raíz desnuda, y el resto es enviado a cultivar con viveristas externos. Para esto se realiza el diseño técnico del vivero, considerando tanto aspectos económicos como de calidad en el producto obtenido. Se diseña el sistema de producción y la planta productora. El proyecto plantea tres alternativas de las cuales la primera es técnicamente infactible (seguir produciendo en raíz desnuda, producto de la limitación en el uso del bromuro de metilo). La segunda alternativa es llevar las 4.000ha a outsourcing, es decir una externalización de un 100%, esta alternativa factible cuenta con un TIR de 17%, obteniendo un VAN de 97millonesaunatasade1297 millones a una tasa de 12%. La tercera alternativa cosiste en construir la planta diseñada para la producción de plantines, esto de forma gradual, comenzado los dos primeros años con un nivel de outsourcing de un 50%, para llegar a completar la producción de forma interna, al tercer año. Los resultados fueron una TIR de 25% y un VAN de 807 millones a una tasa del 12%. Resultando la última más conveniente tanto económicamente como en términos de seguridad en el abastecimiento, además que otorgar ventajas respecto a su competencia
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