2,276 research outputs found

    Charactersing a holographic modal phase mask for the detection of ocular aberrations

    Get PDF
    This is the final version of the article. Available from Society of Photo-optical Instrumentation Engineers (SPIE) via the DOI in this record.The accurate measurement of the double-pass ocular wave front has been shown to have a broad range of applications from LASIK surgery to adaptively corrected retinal imaging. The ocular wave front can be accurately described by a small number of Zernike circle polynomials. The modal wave front sensor was first proposed by Neil et al. and allows the coefficients of the individual Zernike modes to be measured directly. Typically the aberrations measured with the modal sensor are smaller than those seen in the ocular wave front. In this work, we investigated a technique for adapting a modal phase mask for the sensing of the ocular wave front. This involved extending the dynamic range of the sensor by increasing the pinhole size to 2.4mm and optimising the mask bias to 0.75λ. This was found to decrease the RMS error by up to a factor of three for eye-like aberrations with amplitudes up to 0.2μm. For aberrations taken from a sample of real-eye measurements a 20% decrease in the RMS error was observed

    Rapid flow cytometric measurement of protein inclusions and nuclear trafficking.

    Get PDF
    Proteinaceous cytoplasmic inclusions are an indicator of dysfunction in normal cellular proteostasis and a hallmark of many neurodegenerative diseases. We describe a simple and rapid new flow cytometry-based method to enumerate, characterise and, if desired, physically recover protein inclusions from cells. This technique can analyse and resolve a broad variety of inclusions differing in both size and protein composition, making it applicable to essentially any model of intracellular protein aggregation. The method also allows rapid quantification of the nuclear trafficking of fluorescently labelled molecules

    Effect of Phenylephrine on the Accommodative System.

    Get PDF
    Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia. During accommodation the pupil constricts to increase the depth of focus of the eye and improve retinal image quality. Researchers have traditionally faced the challenge of measuring the accommodative properties of the eye through a small pupil and thus have relied on pharmacological agents to dilate the pupil. Achieving pupil dilation (mydriasis) without affecting the accommodative ability of the eye (cycloplegia) could be useful in many clinical and research contexts. Phenylephrine hydrochloride (PHCl) is a sympathomimetic agent that is used clinically to dilate the pupil. Nevertheless, first investigations suggested some loss of functional accommodation in the human eye after PHCl instillation. Subsequent studies, based on different measurement procedures, obtained contradictory conclusions, causing therefore an unexpected controversy that has been spread almost to the present days. This manuscript reviews and summarizes the main research studies that have been performed to analyze the effect of PHCl on the accommodative system and provides clear conclusions that could help clinicians know the real effects of PHCl on the accommodative system of the human eye

    Controlling molten carbonate distribution in dual-phase molten salt-ceramic membranes to increase carbon dioxide permeation rates

    Get PDF
    Dual-phase molten salt-ceramic membranes show high permselectivity for CO2 when molten carbonate is supported in a porous oxygen-ion and/or electron conductor. In this arrangement, the support likely contributes to permeation. Thus, if one is to understand and ultimately design membranes, it is also important to perform experiments with an inert support where permeation relies upon the molten carbonate properties alone. Here, a nominally inert material (Al2O3) was used in order to restrict permeation to molten carbonate. Model Al2O3 dual-phase membranes were fabricated using laser drilling to provide an order of magnitude difference in molten salt-gas interfacial area between feed and permeate sides. Molten carbonate thickness in the model membranes was also varied, independent of the molten salt-gas interfacial area. For all thicknesses studied, CO2 permeation rates showed a significant temperature dependence from 500 to 750 °C, suggesting an activated process was rate-limiting, likely a permeate-side molten salt-gas interfacial process, i.e. desorption of CO2. We applied these findings in asymmetric hollow-fibre supports, a geometry with inherent modularity and scalability, by developing a new carbonate infiltration method to control molten carbonate distribution within the hollow fibre. Compared to a conventionally prepared dual-phase hollow-fibre membrane with an uncontrolled distribution of carbonates, permeation rates were increased by up to 4 times when the molten salt was confined to the packed-pore network, i.e. without infiltrating the hollow-fibre micro-channels. X-ray micro-CT investigations supported the idea that the resulting increase in interfacial area for desorption of CO2 was the key structural difference contributing to increased permeation rates. For CO2 separation, where large volumes of gas must be processed, such increases in permeation rates will reduce the demand for membrane materials, although one must note the higher permeation rates achievable with oxygen-ion and/or electron conducting supports

    A randomized trial to compare exercise treatment methods for patients after total knee replacement: Protocol paper Rehabilitation, physical therapy and occupational health

    Get PDF
    Background: Although the outcome of total knee replacement (TKR) is favorable, surgery alone fails to resolve the functional limitations and physical inactivity that existed prior to surgery. Exercise is likely the only intervention capable of improving these persistent limitations, but exercises have to be performed with intensity sufficient to promote significant changes, at levels that cannot be tolerated until later stages post TKR. The current evidence is limited regarding the effectiveness of exercise at a later stage post TKR. To that end, this study aims to compare the outcomes of physical function and physical activity between 3 treatment groups: clinic-based individual outpatient rehabilitative exercise during 12 weeks, community-based group exercise classes during 12 weeks, and usual medical care (wait-listed control group). The secondary aim is to identify baseline predictors of functional recovery for the exercise groups. Methods/Design: This protocol paper describes a comparative effectiveness study, designed as a 3-group single-blind randomized clinical trial. Two hundred and forty older adults who underwent TKR at least 2 months prior will be randomized into one of the three treatment approaches. Data will be collected at baseline, 3 months, and 6 months. The wait-listed control group will be randomized to one of the 2 exercise groups after 6 months of study participation, and will complete a 9-month follow-up. Primary outcome is physical function measured by the Western Ontario and McMaster Universities Osteoarthritis Index Physical Function Subscale (WOMAC-PF). Physical function is also measured by performance-based tests. Secondary outcomes include performance-based tests and physical activity assessed by a patient-reported survey and accelerometry-based physical activity monitors. Exploratory outcomes include adherence, co-interventions, attrition, and adverse events including number of falls. Linear mixed models will be fitted to compare the changes in outcome across groups. Logistic regression will identify patient characteristics that predict functional recovery in the exercise groups. Instrumental variable methods will be used to estimate the efficacy of the interventions in the presence of non-compliance. Discussion: Results will inform recommendations on exercise programs to improve physical function and activity for patients at the later stage post TKR and help tailor interventions according with patients' characteristics. Trial registration: ClinicalTrials.gov Identifier NCT02237911

    Use of Molecular Markers to Assist the Development of Inbred Lines under Open Field Conditions: the Case of Criollo Peppers (Capsicum annuum L.) from Mexico

    Full text link
    [EN] Chile peppers are one of the most important crops in Mexico and a plethora of ecotypes can be found there. Most of them are ancient open-pollinated (OP) landraces selected by farmers for uniform phenotype but with an inherent level of genetic diversity, called criollos. In this work 15 pepper accessions, encompassing 2 criollo lines, their open-pollinated progenies, and 5 controls, were characterized with a set of 36 IPGRI descriptors and 23 SSR markers to assess the effect of open pollination in the inbreeding process. Heterozygosity levels were comprised between 12 and 47% in the progenies, which were similar or lower than those values from parent plants and similar or higher than control cultivars. Also, both progenies and parents showed similar levels of agronomic and morphological uniformity. Our results suggest that this OP program is efficient in terms of reaching enough agronomic uniformity in criollo Ancho peppers while preserving certain genetic diversity to confer adaptation to climate change.This work was partly financed by projects INIA RTA2013-00022-C02-02 and RTA2014-00041-C02-02, funded by Instituto Nacional Investigaciones Agrarias (Spain), FEDER funds. Also, Mexican authors thank CONACYT for financing the stay of Gustavo Chavez-Gonzalez in Spain, as well as the Programa Integral de Fortalecimiento Institucional (PIFI) de la UA de Aguascalientes (SEP-Mexico).Pereira-Días, L.; Chavez-Gonzalez, G.; Bracho Gil, M.; Fita, A.; Vilanova Navarro, S.; Luna-Ruiz, J.; Perez-Cabrera, L.... (2017). Use of Molecular Markers to Assist the Development of Inbred Lines under Open Field Conditions: the Case of Criollo Peppers (Capsicum annuum L.) from Mexico. Notulae Botanicae Horti Agrobotanici Cluj-Napoca. 45(2):365-368. https://doi.org/10.15835/nbha45210940S36536845

    ¿Por qué no despierta mi paciente? Neumoencéfalo masivo tras craneotomía programada.

    Get PDF
    Our article is about complications arising from intracranial neurosurgery that could be the cause a delay in awakening of patients one surgery is is done.  In this case is about post craniotomy pneumoencephalon (regarding a situation we had at Albacete hospital), its prevalence, clinical implications and complications associated to it, as well as its handling.Nuestro trabajo habla de las complicaciones derivadas de la neurocirugía intracraneal que pueden ser causa de un retraso en el despertar de los pacientes una vez finalizada la intervención quirúrgica. En este caso, hablamos del neumoencéfalo secundario a craneotomía ( a colación de un caso que tuvimos en el hospital de Albacete), su incidencia, repercusiones clínicas y posibles complicaciones asociadas al mismo, así como su manejo

    ¿Por qué no despierta mi paciente? Neumoencéfalo masivo tras craneotomía programada.

    Get PDF
    Nuestro trabajo habla de las complicaciones derivadas de la neurocirugía intracraneal que pueden ser causa de un retraso en el despertar de los pacientes una vez finalizada la intervención quirúrgica. En este caso, hablamos del neumoencéfalo secundario a craneotomía ( a colación de un caso que tuvimos en el hospital de Albacete), su incidencia, repercusiones clínicas y posibles complicaciones asociadas al mismo, así como su manejo. ABSTRACT Our article is about complications arising from intracranial neurosurgery that could be the cause a delay in awakening of patients one surgery is is done.  In this case is about post craniotomy pneumoencephalon (regarding a situation we had at Albacete hospital), its prevalence, clinical implications and complications associated to it, as well as its handling
    corecore