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2021 ◽  
Author(s):  
Mauro Masili ◽  
Fernanda Oliveira Duarte ◽  
Liliane Ventura

Abstract Blue-light transmittance in sunglasses plays an important role for the consumer regarding eye health. Current standards do not have specific requirements for blue-light protection, as in the past. However, the literature has warned about the potential harms of blue light for the eye. The limits imposed in the past state that the average transmission in the 380 nm to 500 nm region should not exceed 1.2X the transmittance in the visible range (380 nm – 780 nm). This work investigates, besides the transmittance of blue light in sunglasses, whether those limits imposed aiming to eye health are respected. Additionally, this study examines the blue-light transmittances pre- and post-artificially aging the material in a solar simulator. Twelve samples of sunglasses were tested for compliance with a former standard and submitted to the aging process up to 2500 h within the solar simulator. The results showed relevant changes in the lenses over time, that is, they considerably lost their blue-light attenuation capabilities. The results suggest that the aging test should be carried out on sunglasses not only for ultraviolet radiation, as required by most standards, but also for blue light. Furthermore, the standards should comprise some constraints concerning the blue-light attenuation.


2021 ◽  
Vol 22 (19) ◽  
pp. 10628
Author(s):  
Camila Ramão Contessa ◽  
Gabriela Silveira da Rosa ◽  
Caroline Costa Moraes

The objective of this work was to develop a chitosan/agar-agar bioplastic film incorporated with bacteriocin that presents active potential when used as food packaging. The formulation of the film solution was determined from an experimental design, through the optimization using the desirability function. After establishing the concentrations of the biopolymers and the plasticizer, the purified bacteriocin extract of Lactobacillus sakei was added, which acts as an antibacterial agent. The films were characterized through physical, chemical, mechanical, barrier, and microbiological analyses. The mechanical properties and water vapor permeability were not altered by the addition of the extract. The swelling property decreased with the addition of the extract and the solubility increased, however, the film remained intact when in contact with the food, thus allowing an efficient barrier. Visible light protection was improved by increased opacity and antibacterial capacity was effective. When used as Minas Frescal cream cheese packaging, it contributed to the increase of microbiological stability, showing a reduction of 2.62 log UFC/g, contributing a gradual release of the active compound into the food during the storage time. The film had an active capacity that could be used as a barrier to the food, allowing it to be safely packaged.


Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1155
Author(s):  
Eva Garcia-Lopez ◽  
Paula Alcazar ◽  
Cristina Cid

Cold-loving microorganisms of all three domains of life have unique and special abilities that allow them to live in harsh environments. They have acquired structural and molecular mechanisms of adaptation to the cold that include the production of anti-freeze proteins, carbohydrate-based extracellular polymeric substances and lipids which serve as cryo- and osmoprotectants by maintaining the fluidity of their membranes. They also produce a wide diversity of pigmented molecules to obtain energy, carry out photosynthesis, increase their resistance to stress and provide them with ultraviolet light protection. Recently developed analytical techniques have been applied as high-throughoutput technologies for function discovery and for reconstructing functional networks in psychrophiles. Among them, omics deserve special mention, such as genomics, transcriptomics, proteomics, glycomics, lipidomics and metabolomics. These techniques have allowed the identification of microorganisms and the study of their biogeochemical activities. They have also made it possible to infer their metabolic capacities and identify the biomolecules that are parts of their structures or that they secrete into the environment, which can be useful in various fields of biotechnology. This Review summarizes current knowledge on psychrophiles as sources of biomolecules and the metabolic pathways for their production. New strategies and next-generation approaches are needed to increase the chances of discovering new biomolecules.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1017
Author(s):  
Aleksandra Gostyńska ◽  
Joanna Starkowska ◽  
Paulina Sobierajska ◽  
Anna Jelińska ◽  
Maciej Stawny

The administration of three-in-one parenteral nutrition (PN) admixtures to pediatric patients requires special consideration, specifically concerning quality and physicochemical stability. The introduction of a new parenteral amino acid solution into the market prompted us to evaluate Aminoplasmal Paed-based PN admixtures’ stability. The study aimed to determine the physicochemical parameters of the chosen variations of PN admixtures and search for a correlation between its composition and those parameters. One hundred and sixty-eight variations of PN admixtures intended for patients weighing from 10 to 25 kg and aged from 1 to 12 years and differing in the quantitative composition of electrolytes were selected for the study. The samples were prepared using each of the four intravenous lipid emulsions dedicated to pediatric patients: Intralipid 20%, Clinoleic 20%, Lipidem 20%, and Smoflipid 20%. The stability of the PN admixtures was assessed by visual inspection and determination of pH, osmolality, zeta potential, and hydrodynamic mean droplet diameter (MDD) immediately upon preparation and after seven days of storage at the temperature of 5 ± 1 °C with light protection. Pearson’s correlation was used to quantify the relationships between selected ingredients of the PN admixtures and the physicochemical parameters. The PN admixtures were characterized by pH ranging from 5.91 to 7.04, osmolality ranging from 1238 to 1678 mOsm/kg, and zeta potential ranging from −41.3 to −2.16 mV. The changes in pH and osmolality after seven days of storage did not exceed 0.2 and 4.4%, respectively. The homogeneity of the PN admixtures was confirmed by determining the polydispersity index, which ranged from 0.06 to 0.2. The MDD of the studied formulas ranged from 235 to 395 nm and from 233 to 365 nm immediately upon preparation and after the storage period, respectively. Correlations between selected components of the PN admixtures and some physicochemical parameters were found. All Aminoplasmal Paed 10%-based PN admixtures were characterized by appropriate physicochemical quality to be administered via the central veins, both immediately upon preparation and after seven days of storage at the temperature of 5 ± 1 °C with light protection. The applied electrolyte concentrations ranges and types of lipid emulsions in the selected macronutrient quantitative compositions allowed the PN admixtures to remain stable for seven days within the specified limits.


Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1464
Author(s):  
Maria Gabriela De Paola ◽  
Rosy Paletta ◽  
Catia Giovanna Lopresto ◽  
Giuseppe Emanuele Lio ◽  
Antonio De Luca ◽  
...  

Starch-based films are promising alternatives to synthetic films in food packaging. They were widely studied in terms of mechanical and optical properties. In food packaging, optical properties are of great interest because ultra violet (UV-light) protection is strictly required. Nevertheless, the characterization of film-forming dispersions was poorly addressed, especially regarding its correlation with the film produced. In this work, we characterized film-forming dispersions at different compositions of starch and carboxymethyl cellulose (CMC) by Turbiscan. This instrument is based on multiple light scattering and gives significant information about the miscibility of polymers in the dispersed phase. Indeed, it identifies the phenomena of destabilization and phase separation before their visibility to the unaided eye. This work aimed to study whether the homogeneous/inhomogeneous morphology of films could be forecast by the analysis of profiles obtained in the dispersed phase. The films produced were investigated by optical microscopy and absorbance analysis. As the CMC fraction increased, Turbiscan showed reduced phase separation. This implies better miscibility of mixture components and higher gelification degree. The related film was more homogeneous and presented higher UV absorbance. Consequently, film-forming dispersions and optical properties of films are strictly correlated and Turbiscan-based analysis is very useful to investigate the dispersion stability and predict the film quality.


2021 ◽  
Vol 37 (3) ◽  
pp. 36-40
Author(s):  
Benjamin Axmann ◽  
Frank Langner ◽  
Chihao Xu ◽  
Karlheinz Blankenbach ◽  
Mirko Conrad ◽  
...  
Keyword(s):  

Solar Energy ◽  
2021 ◽  
Vol 220 ◽  
pp. 852-863
Author(s):  
N.P. Klochko ◽  
V.A. Barbash ◽  
K.S. Klepikova ◽  
V.R. Kopach ◽  
I.I. Tyukhov ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2114
Author(s):  
Karol Bula ◽  
Łukasz Klapiszewski ◽  
Adam Piasecki ◽  
Teofil Jesionowski

In this study, MgO-lignin (MgO-L) dual phase fillers with varying amounts of lignin as well as pristine lignin and magnesium oxide were used as effective bio-fillers to increase the ultraviolet light protection and enhance the barrier performance of low density polyethylene (LDPE) thin sheet films. Differential scanning calorimetry (DSC) was used to check the crystalline structure of the studied samples, and scanning electron microscopy (SEM) was applied to determine morphological characteristics. The results of optical spectrometry in the range of UV light indicated that LDPE/MgO-L (1:5 wt/wt) composition exhibited the best protection factor, whereas LDPE did not absorb ultraviolet waves. Moreover, the addition of hybrid filler decreased the oxygen permeability factor and water vapor transmission compared with neat LDPE and its composites with pristine additives, such as lignin and magnesium oxide. The strong influence of the microstructure on thin sheet films was observed in the DSC results, as double melting peaks were detected only for LDPE compounded with inorganic-organic bio-fillers: LDPE/MgO-L.


2021 ◽  
Vol 12 ◽  
Author(s):  
Yuting Liu ◽  
Mutsumi Watanabe ◽  
Sayuri Yasukawa ◽  
Yuriko Kawamura ◽  
Chaiwat Aneklaphakij ◽  
...  

Plants produce a variety of floral specialized (secondary) metabolites with roles in several physiological functions, including light-protection, attraction of pollinators, and protection against herbivores. Pigments and volatiles synthesized in the petal have been focused on and characterized as major chemical factors influencing pollination. Recent advances in plant metabolomics have revealed that the major floral specialized metabolites found in land plant species are hydroxycinnamates, phenolamides, and flavonoids albeit these are present in various quantities and encompass diverse chemical structures in different species. Here, we analyzed numerous floral specialized metabolites in 20 different Brassicaceae genotypes encompassing both different species and in the case of crop species different cultivars including self-compatible (SC) and self-incompatible (SI) species by liquid chromatography-mass spectrometry (LC-MS). Of the 228 metabolites detected in flowers among 20 Brassicaceae species, 15 metabolite peaks including one phenylacyl-flavonoids and five phenolamides were detected and annotated as key metabolites to distinguish SC and SI plant species, respectively. Our results provide a family-wide metabolic framework and delineate signatures for compatible and incompatible genotypes thereby providing insight into evolutionary aspects of floral metabolism in Brassicaceae species.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 723
Author(s):  
Naerin Baek ◽  
Young Kim ◽  
Susan Duncan ◽  
Kristen Leitch ◽  
Sean O’Keefe

The light-protective effectiveness of titanium dioxide polylactic acid (TiO2 PLA) nanocomposite films (T-PLA) and oleic-acid-modified (OA_TiO2PLA) nanocomposite films was investigated in ready-to-drink (RTD) green tea infusions in oxygen-impermeable glass packaging. The stability of (-)-epigallocatechin gallate (EGCG) was evaluated in RTD green tea infusions in glass packaging covered with PLA (polylactic acid), T-PLA and OT-PLA under fluorescent light during 20 days of storage at 4 °C. Levels of EGCG and color change of RTD green tea infusions were determined. In addition, sensory tests for difference were conducted on green tea infusions in glass packaging without and with complete light protection during 10 days of storage at 4 °C. Of the panelists, 60% noticed sensory differences in the RTD green tea infusion in two different packaging conditions during 10 days of storage under fluorescent light by a triangle test (p < 0.05). During 20 days of storage, levels of EGCG with complete light protection decreased by 10.8% (0.73 mg/mL), and there was a 42.2% loss of EGCG (0.48 mg/mL) in RTD green tea infusions in the glass packaging covered by PLA film. Finally, 3% T-PLA preserved higher levels of EGCG in RTD green tea infusions compared to 1% T-PLA and OT-PLA.


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