Crosslinked agarose encapsulated sorbents resistant to steam sterilization. Preparation and mechanical properties

The application of agarose in hemoperfusion is hampered by the lack of a suitable sterilization method. A technique has been developed for the crosslinking of agarose encapsulated sorbents by the reaction with 1,3-dichloro-2-propanol (DCP) under strong alkaline conditions. A twofold molar excess of DCP with respect to agarose and an equimolar amount of sodium hydroxide at a concentration of 0.3 mol/L with a reaction time of 1-4 h at 50°C are found to be the optimal conditions. The compressive strength of crosslinked beads is increased by a factor of 4. Agarose capsules are found to degrade by the influence of Y radiation, but are resistant to steam sterilization at 134°C during at least 30 min when crosslinked

Results of the AEROS satellite program: Summary

Published literature reporting aeronomic data collected on two AEROS missions is summarized. The extreme ultraviolet solar radiation and other significant parameters of the thermosphere/ionosphere were investigated. Kinetic pressure, the quantity of atomic nitrogen, and partial densities of helium, oxygen, nitrogen, argon, and atomic nitrogen were determined. The thermal electron population, superthermal energy distribution, plasma density, ion temperature, and composition according to ion types were measured. The chief energy supply in the thermosphere was calculated. Aeronomic calculations showing that variations in the parameters of the ionosphere cannot be correlated with fluctuations of extreme ultraviolet solar radiation were performed. The AEROS data were compared with data from S3-1, ISIS, and AE-C satellites. Models of the thermosphere and ionosphere were developed

Through-focus response of multifocal intraocular lenses evaluated with a spatial light modulator

A new testing technique based on the use of a liquid crystal spatial light modulator (SLM) is proposed to analyze the optical quality of multifocal intraocular lenses (MIOLs). Different vergences and decentrations of the incident beam can be programmed onto the SLM in order to record the point spread function (PSF) for different object positions. From these axial PSFs, the through-focus modulation transfer function is computed. Because there are no moving parts in the experimental setup, this method is fast and versatile to assess MIOLs. Experimental results confirm the potential of the proposed method.We acknowledge the financial support from Ministerio de Ciencia e Innovacion (grants FIS2011-23175 and TRA2009-0215), Generalitat Valenciana (grant PROMETEO2009-077), and Universitat Politecnica de Valencia (PAID-05-11), Spain. L. Remon acknowledges a fellowship of "Fundacion Cajamurcia," Spain.Remón Martín, L.; Arias, A.; Calatayud Calatayud, A.; Furlan, WD.; Monsoriu Serra, JA. (2012). Through-focus response of multifocal intraocular lenses evaluated with a spatial light modulator. Applied optics. 36(51):8594-8598. https://doi.org/10.1364/AO.51.008594S859485983651Portney, V. (1992). Optical testing and inspection methodology for modern intraocular lenses. Journal of Cataract & Refractive Surgery, 18(6), 607-613. doi:10.1016/s0886-3350(13)80453-1Rawer, R., Stork, W., Spraul, C. W., & Lingenfelder, C. (2005). Imaging quality of intraocular lenses. Journal of Cataract & Refractive Surgery, 31(8), 1618-1631. doi:10.1016/j.jcrs.2005.01.033Barbero, S., Marcos, S., & Jiménez-Alfaro, I. (2003). Optical aberrations of intraocular lenses measured in vivo and in vitro. Journal of the Optical Society of America A, 20(10), 1841. doi:10.1364/josaa.20.001841Schwiegerling, J., & DeHoog, E. (2010). Problems testing diffractive intraocular lenses with Shack-Hartmann sensors. Applied Optics, 49(16), D62. doi:10.1364/ao.49.000d62Schwiegerling, J. (2007). Analysis of the Optical Performance of Presbyopia Treatments With the Defocus Transfer Function. Journal of Refractive Surgery, 23(9), 965-971. doi:10.3928/1081-597x-20071101-19ATCHISON, D. A. (1989). Optical Design of Intraocular Lenses. III. On-Axis Performance in the Presence of Lens Displacement. Optometry and Vision Science, 66(10), 671-681. doi:10.1097/00006324-198910000-00003Taketani, F., Matuura, T., Yukawa, E., & Hara, Y. (2004). Influence of intraocular lens tilt and decentration on wavefront aberrations. Journal of Cataract & Refractive Surgery, 30(10), 2158-2162. doi:10.1016/j.jcrs.2004.02.072Altmann, G. E., Nichamin, L. D., Lane, S. S., & Pepose, J. S. (2005). Optical performance of 3 intraocular lens designs in the presence of decentration. Journal of Cataract & Refractive Surgery, 31(3), 574-585. doi:10.1016/j.jcrs.2004.09.024Phillips, P., Rosskothen, H. D., Pérez-Emmanuelli, J., & Koester, C. J. (1988). Measurement of intraocular lens decentration and tilt in vivo. Journal of Cataract & Refractive Surgery, 14(2), 129-135. doi:10.1016/s0886-3350(88)80086-5De Castro, A., Rosales, P., & Marcos, S. (2007). Tilt and decentration of intraocular lenses in vivo from Purkinje and Scheimpflug imaging. Journal of Cataract & Refractive Surgery, 33(3), 418-429. doi:10.1016/j.jcrs.2006.10.054Sasaki, K., Sakamoto, Y., Shibata, T., Nakaizumi, H., & Emori, Y. (1989). Measurement of postoperative intraocular lens tilting and decentration using Scheimpflug images. Journal of Cataract & Refractive Surgery, 15(4), 454-457. doi:10.1016/s0886-3350(89)80071-9Eppig, T., Scholz, K., Löffler, A., Meßner, A., & Langenbucher, A. (2009). Effect of decentration and tilt on the image quality of aspheric intraocular lens designs in a model eye. Journal of Cataract & Refractive Surgery, 35(6), 1091-1100. doi:10.1016/j.jcrs.2009.01.034Calatayud, A., Rodrigo, J. A., Remón, L., Furlan, W. D., Cristóbal, G., & Monsoriu, J. A. (2012). Experimental generation and characterization of Devil’s vortex-lenses. Applied Physics B, 106(4), 915-919. doi:10.1007/s00340-012-4913-0Simpson, M. J. (1992). Diffractive multifocal intraocular lens image quality. Applied Optics, 31(19), 3621. doi:10.1364/ao.31.003621ATCHISON, D. A., YE, M., BRADLEY, A., COLLINS, M. J., ZHANG, X., RAHMAN, H. A., & THIBOS, L. N. (1992). Chromatic Aberration and Optical Power of a Diffractive Bifocal Contact Lens. Optometry and Vision Science, 69(10), 797-804. doi:10.1097/00006324-199210000-00009Portney, V. (2011). Light distribution in diffractive multifocal optics and its optimization. Journal of Cataract & Refractive Surgery, 37(11), 2053-2059. doi:10.1016/j.jcrs.2011.04.038Castignoles, F., Flury, M., & Lepine, T. (2010). Comparison of the efficiency, MTF and chromatic properties of four diffractive bifocal intraocular lens designs. Optics Express, 18(5), 5245. doi:10.1364/oe.18.00524

NEX4EX: Novel Exercise Hardware for Exploration

This paper presents the NEX4EX project Novel Exercise Hardware for Exploration, which aims to design, build and validate a full-body countermeasure platform that enables high intensive resistive and plyometric exercise as well as postural control training, and strength training. The NEX4EX exerciser herewith addresses neuromuscular and musculoskeletal deconditioning. The intended use is to improve crew health and fitness maintenance for long-duration space missions beyond ISS lifetime. This will require the system to be multi-purpose / versatile in terms of exercises added to a smaller footprint than systems currently used on ISS. NEX4EX is a novel concept for a novel utilization paradigm given future space exploration-class missions

NEX4EX: Novel Exercise Hardware for Exploration

This paper presents the NEX4EX project Novel Exercise Hardware for Exploration, which aims to design, build and validate a full-body countermeasure platform that enables high intensive resistive and plyometric exercise as well as postural control training, and strength training. The NEX4EX exerciser herewith addresses neuromuscular and musculoskeletal deconditioning. The intended use is to improve crew health and fitness maintenance for long-duration space missions beyond ISS lifetime. This will require the system to be multi-purpose / versatile in terms of exercises added to a smaller footprint than systems currently used on ISS. NEX4EX is a novel concept for a novel utilization paradigm given future space exploration-class missions

Potential Application of Whole Body Vibration Exercise for Improving the Clinical Conditions of COVID-19 Infected Individuals: A Narrative Review from the World Association of Vibration Exercise Experts (WAVex) Panel

COVID-19 is a highly infectious respiratory disease which leads to several clinical conditions related to the dysfunction of the respiratory system along with other physical and psychological complaints. Severely affected patients are referred to intensive care units (ICUs), limiting their possibilities for physical exercise. Whole body vibration (WBV) exercise is a non-invasive, physical therapy, that has been suggested as part of the procedures involved with pulmonary rehabilitation, even in ICU settings. Therefore, in the current review, the World Association of Vibration Exercise Experts (WAVEX) reviewed the potential of WBV exercise as a useful and safe intervention for the management of infected individuals with COVID-19 by mitigating the inactivity-related declines in physical condition and reducing the time in ICU. Recommendations regarding the reduction of fatigue and the risk of dyspnea, the improvement of the inflammatory and redox status favoring cellular homeostasis and the overall improvement in the quality of life are provided. Finally, practical applications for the use of this paradigm leading to a better prognosis in bed bound and ICU-bound subjects is proposed

Progressive adaptation in physical activity and neuromuscular performance during 520d confinement

To understand whether prolonged confinement results in reductions in physical activity and adaptation in the musculoskeletal system, six subjects were measured during 520 d isolation in the Mars500 study. We tested the hypothesis that physical activity reduces in prolonged confinement and that this would be associated with decrements of neuromuscular performance. Physical activity, as measured by average acceleration of the body\u27s center of mass ("activity temperature") using the actibelt® device, decreased progressively over the course of isolation (p<0.00001). Concurrently, countermovement jump power and single-leg hop force decreased during isolation (p<0.001) whilst grip force did not change (p≥0.14). Similar to other models of inactivity, greater decrements of neuromuscular performance occurred in the lower-limb than in the upper-limb. Subject motivational state increased non-significantly (p = 0.20) during isolation, suggesting reductions in lower-limb neuromuscular performance were unrelated to motivation. Overall, we conclude that prolonged confinement is a form of physical inactivity and is associated with adaptation in the neuromuscular system

Gradient Optics of subwavelength nanofilms

Propagation and tunneling of light through subwavelength photonic barriers, formed by dielectric layers with continuous spatial variations of dielectric susceptibility across the film are considered. Effects of giant heterogeneity-induced non-local dispersion, both normal and anomalous, are examined by means of a series of exact analytical solutions of Maxwell equations for gradient media. Generalized Fresnel formulae, visualizing a profound influence of gradient and curvature of dielectric susceptibility profiles on reflectance/transmittance of periodical photonic heterostructures are presented. Depending on the cutoff frequency of the barrier, governed by technologically managed spatial profile of its refractive index, propagation or tunneling of light through these barriers are examined. Nonattenuative transfer of EM energy by evanescent waves, tunneling through dielectric gradient barriers, characterized by real values of refractive index, decreasing in the depth of medium, is shown. Scaling of the obtained results for different spectral ranges of visible, IR and THz waves is illustrated. Potential of gradient optical structures for design of miniaturized filters, polarizers and frequency-selective interfaces of subwavelength thickness is considered

Characterizing dual wavelength polarimetry through the eye for monitoring glucose

Diabetes is an insidious disease that afflicts millions of people worldwide and typically requires the person with the disease to monitor their blood sugar level via finger or forearm sticks multiple times daily. Therefore, the ability to noninvasively measure glucose would be a significant advancement for the diabetic community. The use of optically polarized light passed through the anterior chamber of the eye is one proposed noninvasive approach for glucose monitoring. However, the birefringence of the cornea and the difficulty in coupling the light across the eye have been major drawbacks toward realizing this approach. A dual wavelength optical polarimetric approach has been proposed as a means to potentially overcome the birefringence noise but has never been fully characterized. Therefore, in this paper an optical model has been developed along with experiments performed on New Zealand White rabbit eyes for characterizing the light path and corneal birefringence at two different wavelengths as they are passed through the anterior chamber of the eye. The results show that, without index matching, it is possible to couple the light in and out of the eye but only across a very limited range otherwise the light does not come back out of the eye. It was also shown that there is potential to use a dual wavelength approach to accommodate the birefringence noise of the cornea in the presence of eye motion. These results will be used to help guide the final design of the polarimetric system for use in noninvasive monitoring of glucose in vivo