888 research outputs found

    Comparación de la calidad óptica de lentes intraoculares esféricas y asféricas en presencia de errores de posición

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    El cristalino de un ojo sano es transparente y actúa como una lente de focal o poder refractivo variable. A medida que envejecemos, las proteínas en el cristalino comienzan a descomponerse y éste se torna progresivamente más opaco formándose una catarata. El único tratamiento para una catarata es la implantación de lentes intraoculares (LIO) a través de facoemulsificación. Las LIOs monofocales implantadas pueden ser de diseño esférico o de diseño asférico.Este trabajo consiste en comparar en banco óptico el comportamiento de una LIO monofocal esférica y el de una asférica en presencia de descentramiento. Para ello se utilizaran métricas de calidad, como la función de punto extendido (PSF) y la función de transferencia de modulación (MTF) del sistema. Se evaluará cuál de los dos diseños presenta mejor calidad óptica tanto en condiciones de buen centrado de la LIO como con descentramiento. De este modo se podrá establecer la robustez de cada diseño frente al desplazamiento.Una vez analizados todos los datos, se aprecia con claridad que la mejor imagen que podemos obtener en una posición centrada se consigue mediante la lente de diseño asférico, mientras que en presencia de descentramiento, la lente esférica presenta claramente una mayor robustez

    A qualitative study on the experiences of southern European immigrant parents navigating the Norwegian healthcare system

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    Background Patients’ experiences with health providers and their diagnostic and treatment expectations are shaped by cultural health beliefs and previous experiences with healthcare services in home country. This study explores how Southern European immigrant parents navigate the Norwegian healthcare system, through its focus on how this group manage their expectations on diagnosis and treatment practices when these are unmet. Methods The study had a qualitative research design. Fourteen in-depth interviews and two focus group discussions with 20 Southern European immigrant parents were conducted in 2017 in three Norwegian municipalities. With the help of NVivo software, data were transcribed verbatim and coded. Following a thematic analysis approach to identify patterns in immigrants’ experiences with the Norwegian healthcare services, the codes were organized into two themes. Results The first theme includes immigrants’ expectations on diagnostic tests and medical treatment. Southern European immigrants expected more diagnostic tests and pharmacological treatment than what was deemed necessary by Norwegian health providers. Experiences with unmet expectations influenced how immigrants addressed their and their children’s healthcare needs. The second theme comprises immigrants’ experiences of seeking healthcare in Norway (attending medical consultations in the private sector, seeking immigrant healthcare providers, and navigating the healthcare through their Norwegian social networks). This category includes also the alternative solutions immigrants undertook when they were dissatisfied with the diagnosis and treatment practices they were offered in Norway (self-medication and seeking healthcare in home countries). Conclusions Cultural health beliefs and previous experiences with healthcare services from home country shaped immigrants’ expectations on diagnosis and treatment practices. This had great implications for their navigation through the healthcare system and interactions with health providers in the host country. The study suggests that successful inclusion of immigrants into the Norwegian healthcare system requires an acknowledgment of the cultural factors that influence access and use of healthcare services. Exploring immigrants’ perspectives and experiences offers important information to understand the challenges of cross-cultural healthcare and to improve communication and equitable access.publishedVersio

    Optical detection of the radio supernova SN 2000ft in the circumnuclear region of the luminous infrared galaxy NGC 7469

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    SN 2000ft is detected in two independent Planetary Camera images (F547W and F814W) taken May 13, 2000, about two months before the predicted date of the explosion (July 19, 2000), based on the analysis of its radio light evolution by Alberdi and collaborators. The apparent optical magnitudes and red color of SN 2000ft indicate that it is observed through an extinction of at least AV_V= 3.0 magnitudes. The extinction corrected lower limit to the absolute visual magnitude (MV_V ≤−\leq - 18.0), identifies SN 2000ft as a luminous supernova in the optical, as other luminous radio supernovae before. SN 2000ft exploded in a region located at only 0.1 arcsec (i.e. 34 +/- 3 pc) west of a faint cluster (C24). No parent cluster is identified within the detection limits of the HST short exposures. The unambiguous detection of SN 2000ft in the visual shows that multi-epoch sub-arcsecond (FWHM less than 0.1 arcsec) optical imaging is also a valid tool that should be explored further to detect supernovae in the dusty (circum)nuclear regions of (U)LIRGs

    Differential in vitro and in vivo effect of barley cysteine and serine protease inhibitors on phytopathogenic microorganisms

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    Protease inhibitors from plants have been involved in defence mechanisms against pests and pathogens. Phytocystatins and trypsin/α-amylase inhibitors are two of the best characterized protease inhibitor families in plants. In barley, thirteen cystatins (HvCPI-1 to 13) and the BTI-CMe trypsin inhibitor have been previously studied. Their capacity to inhibit pest digestive proteases, and the negative in vivo effect caused by plants expressing these inhibitors on pests support the defence function of these proteins. Barley cystatins are also able to inhibit in vitro fungal growth. However, the antifungal effect of these inhibitors in vivo had not been previously tested. Moreover, their in vitro and in vivo effect on plant pathogenous bacteria is still unknown. In order to obtain new insights on this feature, in vitro assays were made against different bacterial and fungal pathogens of plants using the trypsin inhibitor BTI-CMe and the thirteen barley cystatins. Most barley cystatins and the BTI-CMe inhibitor were able to inhibit mycelial growth but no bacterial growth. Transgenic Arabidopsis plants independently expressing the BTI-CMe inhibitor and the cystatin HvCPI-6 were tested against the same bacterial and fungal pathogens. Neither the HvCPI-6 expressing transgenic plants nor the BTI-CMe ones were more resistant to plant pathogen fungi and bacteria than control Arabidopsis plants. The differences observed between the in vitro and in planta assays against phytopathogenic fungi are discusse

    Stable thrust on a finite-sized magnet above a Meissner superconducting torus

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    Forces and torques exerted by a superconducting torus on a permanent magnet have been mapped. It is demonstrated that stable orbits exist. Moreover, provided that the magnet remains in any of these orbits, the first critical field in the superconductor is never overpassed and the superconductor remains in the Meissner state. The consequent absence of hysteresis makes these kinds of device perfect candidates for non-frictional bearings or gyroscopes.Comment: accepted versio

    Multispectral images of peach related to firmness and maturity at harvest

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    wo multispectral maturity classifications for red soft-flesh peaches (‘Kingcrest’, ‘Rubyrich’ and ‘Richlady’ n = 260) are proposed and compared based on R (red) and R/IR (red divided by infrared) images obtained with a three CCD camera (800 nm, 675 nm and 450 nm). R/IR histograms were able to correct the effect of 3D shape on light reflectance and thus more Gaussian histograms were produced than R images. As fruits ripened, the R/IR histograms showed increasing levels of intensity. Reference measurements such as firmness and visible spectra also varied significantly as the fruit ripens, firmness decreased while reflectance at 680 nm increased (chlorophyll absorption peak)

    Mid-Infrared T-ReCS Spectroscopy of Local LIRGs

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    We present T-ReCS high spatial resolution N-band (8-13 micron) spectroscopy of the central regions (a few kpc) of 3 local LIRGs. The nuclear spectra show deep 9.7 micron silicate absorption feature and the high ionization [SIV]10.5 micron emission line, consistent with their optical classification as AGN. The two LIRGs with unresolved mid-IR emission do not show PAH emission at 11.3 micron in their nuclear spectra. The spatially resolved mid-IR spectroscopy of NGC 5135 allows us to separate out the spectra of the Seyfert nucleus, an HII region, and the diffuse region between them on scales of less than 2.5 arcsec ~ 600 pc. The diffuse region spectrum is characterized by strong PAH emission with almost no continuum, whereas the HII region shows PAH emission with a smaller equivalent width as well as [NeII]12.8 micron line

    Gradient estimates for a degenerate parabolic equation with gradient absorption and applications

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    Qualitative properties of non-negative solutions to a quasilinear degenerate parabolic equation with an absorption term depending solely on the gradient are shown, providing information on the competition between the nonlinear diffusion and the nonlinear absorption. In particular, the limit as time goes to infinity of the mass of integrable solutions is identified, together with the rate of expansion of the support for compactly supported initial data. The persistence of dead cores is also shown. The proof of these results strongly relies on gradient estimates which are first established
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