Integration of statistics and food process engineering: Assessing the uncertainty of thermal processing and shelf-life estimations

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Toward new engagement paradigms for intraocular lenses: Light-initiated bonding of capsular bag to lens materials

8 págs.; 5 figs.© 2015 The Association for Research in Vision and Ophthalmology, Inc. PURPOSE. Successful intraocular lens procedures, that is, implantation of accommodating intraocular lenses (A-IOL), require firm engagement of the IOL haptics to the capsular bag. We evaluated the use of photochemical bonding to engage IOL materials to the capsular bag. METHODS. Freshly enucleated eyes of New Zealand rabbits were used in two types of photobonding experiments using Rose Bengal (RB) photoinitiation and green light (532-nm) irradiation. First, RB-stained capsular bag strips were photobonded ex vivo to IOL polymer [poly(2-hydroxyethyl methacrylate) pHEMA] strips in an atmosphere of air and of nitrogen. Second, IOLs were implanted intracapsularly and photobonded intraocularly. Irradiation times were between 30 and 180 seconds, and laser irradiance was between 0.25 and 0.65 W/cm2. The strength of the bonding was tested using a custom-developed uniaxial extensiometry system and the breakage load (the load that caused breakage per bonded area) was calculated. RESULTS. The breakage load of ex vivo capsule–pHEMA bonds increased exponentially with irradiation time, using 0.45 W/cm2. In air, the average breakage load across all conditions was 1 g/mm2 and 1.6 times lower than that in a nitrogen atmosphere. Intraocularly, RB-stained IOLs were strongly photobonded to the capsule bag with breakage loads > 0.8 g/mm2. CONCLUSIONS. Breakage of the photobonded linkage between IOL material and capsular bag required loads substantially greater than the maximum force of ciliary muscle, suggesting that this technology may introduce a new paradigm for engagement of A-IOLs. The bonding produced in air was stronger than that in nitrogen atmosphere, suggesting that oxygen is involved in the chemical mechanism for photobonding.Supported by European Research Council (ERC) EU Seventh Framework Program (FP/2007-2013)/ERC grant agreement, ERC- 2011-AdC 294099 (SM), Spanish Government Grants FIS2011- 25637 (SM) and FIS2013-49544-EXP (CD), and Juan de la Cierva postdoctoral fellowship (JL).Peer Reviewe

Agroforestry Systems in Cuba: Some Aspects of Animal Production

The silvopastoral systems, that nowadays constitute scientific achievements of the Grasses and Forages Research Station Indio Hatuey , have been developed from the results of investigations that were carried out since the 1980s, to improve the productivity of natural pastures through the introduction of valuable herbaceous species and tree legumes. Those investigations also determined the essential elements of pasture management such as the optimal stocking rates for low input systems and suitable methods of grazing to obtain sustainability of grasslands

Wavelength tuning of polymer optical fibre Bragg grating at longer wavelengths permanently

Permanent Bragg wavelength tuning of polymer optical fibre Bragg grating (POFBG) at longer wavelengths has been demonstrated for the first time utilising the thermal annealing process. In general, exposing the polymer material above its β-Transition temperature, the fibre shrinks in length, the Bragg grating period becomes shorter and the Bragg wavelength shifts permanently to shorter wavelengths. In this work, a positive tuning of Bragg wavelength has been shown to be feasible when the polymer fibre is stretched during its thermal exposure. The results show that the degree of Bragg wavelength tuning strongly depends on the applying fibre strain or equivalently stress. The work presented in this paper can be used to multiplex POFBGs at any desirable wavelength

Agroforestry Systems in Cuba: Some Aspects of Animal Production

The silvopastoral systems, that nowadays constitute scientific achievements of the Grasses and Forages Research Station “Indio Hatuey , have been developed from the results of investigations that were carried out since the 1980s, to improve the productivity of natural pastures through the introduction of valuable herbaceous species and tree legumes. Those investigations also determined the essential elements of pasture management such as the optimal stocking rates for low input systems and suitable methods of grazing to obtain sustainability of grasslands

Novel thermal annealing methodology for permanent tuning polymer optical fiber Bragg gratings to longer wavelengths

The Bragg wavelength of a polymer optical fiber Bragg grating can be permanently shifted by utilizing the thermal annealing method. In all the reported fiber annealing cases, the authors were able to tune the Bragg wavelength only to shorter wavelengths, since the polymer fiber shrinks in length during the annealing process. This article demonstrates a novel thermal annealing methodology for permanently tuning polymer optical fiber Bragg gratings to any desirable spectral position, including longer wavelengths. Stretching the polymer optical fiber during the annealing process, the period of Bragg grating, which is directly related with the Bragg wavelength, can become permanently longer. The methodology presented in this article can be used to multiplex polymer optical fiber Bragg gratings at any desirable spectral position utilizing only one phase-mask for their photo-inscription, reducing thus their fabrication cost in an industrial setting

Infliximab microencapsulation: an innovative approach for intra-articular administration of biologics in the management of rheumatoid arthritis-in vitro evaluation

Microencapsulation of the therapeutical monoclonal antibody infliximab (INF) was investigated as an innovative approach to improve its stability and to achieve formulations with convenient features for intra-articular administration. Ultrasonic atomization (UA), a novel alternative to microencapsulate labile drugs, was compared with the conventional emulsion/evaporation method (Em/Ev) using biodegradable polymers, specifically Polyactive® 1000PEOT70PBT30 [poly(ethylene-oxide-terephthalate)/poly(butylene-terephthalate); PEOT-PBT] and its polymeric blends with poly-(D, L-lactide-co-glycolide) (PLGA) RG502 and RG503 (PEOT-PBT:PLGA; 65:35). Six different formulations of spherical core-shell microcapsules were successfully developed and characterized. The UA method achieved a significantly higher encapsulation efficiency (69.7-80.25%) than Em/Ev (17.3-23.0%). Mean particle size, strongly determined by the microencapsulation method and to a lesser extent by polymeric composition, ranged from 26.6 to 49.9 µm for UA and 1.5-2.1 µm for Em/Ev. All formulations demonstrated sustained INF release in vitro for up to 24 days, with release rates modulated by polymeric composition and microencapsulation technique. Both methods preserved INF biological activity, with microencapsulated INF showing higher efficacy than commercial formulations at comparable doses regarding bioactive tumor necrosis factor-alpha (TNF-α) neutralization according to WEHI-13VAR bioassay. Microparticles' biocompatibility and extensive internalization by THP-1-derived macrophages was demonstrated. Furthermore, high in vitro anti-inflammatory activity was achieved after treatment of THP-1 cells with INF-loaded microcapsules, significatively reducing in vitro production of TNF-α and interleucine-6 (Il-6)Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Iván Lamela-Gómez received funding from the “Axudas á etapa predoutoral da Xunta de Galicia, cofinanciadas polo programa operativo FSE Galicia 2014–2020” predoctoral grant program. Consellería de Cultura, Educación e ordenación universitaria, Xunta de Galicia, Spain. This research was partially funded by Consellería de Cultura, Educación e ordenación universitaria, Xunta de Galicia, Spain. Axudas para a consolidación e estructuración de unidades de investigación competitivas Modalidad A: Grupos de Referencia Competitiva (ED341C 2017/13). This research was also partially funded by the Fundação para a Ciência e a Tecnologia (FCT), Portugal (UID/DTP/04138/2019 and UIDB/04138/2020 to iMed.ULisboa), and principal investigator grants CEECIND/03143/2017 (L. M. Gonçalves)S

Near-field scanning optical microscopy to study nanometric structural details of LiNbO3 Zn-diffused channel waveguides

A near-field scanning optical microscope (NSOM) is used to perform structural and optical characterization of the surface layer after Zn diffusion in a channel waveguide fabricated on lithium niobate. A theoretical approach has been developed in order to extract refractive index contrast from NSOM optical transmission measurements (illumination configuration). As a result, different solid phases present on the sample surface can be identified, such as ZnO and ZnNb2O6. They appear like submicrometric crystallites aligned along the domain wall direction, whose origin can be ascribed to some strain relaxation mechanism during the annealing process after Zn [email protected]