A Technique for Marking Marsupial Pouch Young With Fluorescent Pigment Tattoos

1988 ◽  
Vol 15 (5) ◽  
pp. 561 ◽  
Author(s):  
TR Soderquist ◽  
CR Dickman
Keyword(s):  
Uv Light ◽  
Skin Pigmentation ◽  
Fluorescent Pigment ◽  
Wide Range ◽  
Marsupial Species

Small quantities of fluorescent pigments were tattooed into the pinnae of pouch young Dasyurus geoffroii and Isoodon obesulus (Marsupialia), and into the pinnae of 5-day-old Mus rnusculus (Rodentia). The tattoos contrasted sharply with natural skin pigmentation when scanned with a UV light. Of 11 pigments tested, Flare 610 pigments were the most persistent, remaining visible for a minimum of 6 months. The technique facilitates rapid, cheap and reliable marking of marsupial pouch young, and should be generally applicable for determining filial relationships in a wide range of marsupial species.

Super Nutritive Marine Astaxanthin, an Effectual Dietary Carotenoid for Neurodegenerative Diseases

2019 ◽  
pp. 115-124 ◽  
Author(s):  
Kumaresan Kowsalya ◽  
Nandakumar Vidya ◽  
Vijayraj Vijayalakshmi ◽  
Muthukrishnan Arun
Keyword(s):  
Neurodegenerative Diseases ◽  
Cell Membranes ◽  
Uv Light ◽  
Coenzyme Q ◽  
Skin Pigmentation ◽  
Beta Carotene ◽  
Wide Range ◽  
Commercial Applications ◽  
Dietary Carotenoid ◽  
Single Oxygen

The red-pigmented astaxanthin (3,-3’-dihydroxy-?,?-carotene-4,4’-dione) were commonly found in marine algae and aquatic animals such as shrimp, lobster, and trout. These pigments are produced as secondary metabolites which fall in arytenoids under class xanthophylls. Synthetic astaxanthin has a wide range of commercial applications such as color additives, usage in cosmetics and immune-boosters. In aquaculture, supplementing synthetic astaxanthin as feed, enhances skin pigmentation which possesses commercial importance. However, synthetic astaxanthin is not highly efficient compared to naturally derived counter forms. On the other hand, humans should only depend on microbial and aquatic sources for their dietary intake of natural astaxanthin. Being a powerful antioxidant, natural astaxanthin is called as king of antioxidants which has scavenging activity 6000 times stronger than vitamin C and 50 times more powerful than vitamin E in protecting cell membranes. It also has a single oxygen quenching activity up to 800 times stronger than coenzyme Q, 550 times more powerful than green tea catechins, 4.9 times stronger than beta-carotene and three times stronger than lute in. Furthermore, researchers revealed that this carotenoid has the capacity to alleviate tumor activity, protecting against lipid per oxidation, free radicals, oxidative damage to LDL-cholesterol and UV light affects on cell membranes and tissues. Also, it is mainly recommended for curing the macular degeneration of cataracts. Anti-aging properties of astaxanthin improve skin health by reducing wrinkles and repairs the UV-induced DNA damage in human cells. Interestingly, the ability of astaxanthin in crossing the blood-brain barrier has brought this compound to limelight as a potential target in treating neurodegenerative diseases including Parkinson's and Alzheimer's disease. Hence, in this review, we are mainly focusing on the therapeutic usage of astaxanthin in neurodegenerative diseases.

Green Synthesis of ZnO/Dy/NiO Heterostructures for Enhanced Photocatalytic Applications

2020 ◽  
Vol 1 (1) ◽  
pp. 30-36
Author(s):  
Shubha Jayachamarajapura Pranesh ◽  
Diwya Lanka
Keyword(s):  
Visible Light ◽  
Uv Light ◽  
Combustion Method ◽  
Hybrid Nanocomposites ◽  
Synthetic Dyes ◽  
Hybrid Nanostructure ◽  
Wide Range ◽  
Visible Light Active ◽  
Textile Industries ◽  
Photocatalytic Applications

Background: Textile industries discharge harmful synthetic dyes to nearby water sources. These colour effluents should be treated before discharge to reduce the toxicity caused by synthetic colours. Objective: To synthesize visible light active superstructures to reduce water pollution caused by textile industries. Methods: We have successfully synthesized ZnO/Dy/NiO hybrid nanocomposites using waste curd as fuel by a simple combustion method. The obtained material was able to reduce recombination and enhanced the photocatalytic degradation of organic pollutants. The as-synthesized material was characterized by XRD, absorption spectroscopy, FESEM, EDAX, etc. The obtained hybrid nanostructure was used as a photocatalyst for the degradation of methylene blue under sunlight, UV light as well as in dark. Comparative experiments were carried out with a variation of catalytic load, pH, dye concentrations, etc. for a better understanding of the performance of the catalyst at various conditions. Results and Conclusion: The ternary compound shows wide range of absorption by expanding absorption band both in UV and visible regions. ZnO/Dy/NiO hybrid nanocomposites performed well and showed uniqueness in the activity uder visible light.

scholarly journals Melanogenesis Connection with Innate Immunity and Toll-Like Receptors

2020 ◽  
Vol 21 (24) ◽  
pp. 9769
Author(s):  
Saaya Koike ◽  
Kenshi Yamasaki
Keyword(s):  
Skin Pigmentation ◽  
Innate Immune ◽  
Mitogen Activated Protein Kinase ◽  
Ultraviolet Rays ◽  
Toll Like Receptors ◽  
Pigment Formation ◽  
Living Body ◽  
Pigmentary Disorders ◽  
Wide Range ◽  
Griscelli Syndrome

The epidermis is located in the outermost layer of the living body and is the place where external stimuli such as ultraviolet rays and microorganisms first come into contact. Melanocytes and melanin play a wide range of roles such as adsorption of metals, thermoregulation, and protection from foreign enemies by camouflage. Pigmentary disorders are observed in diseases associated with immunodeficiency such as Griscelli syndrome, indicating molecular sharing between immune systems and the machineries of pigment formation. Melanocytes express functional toll-like receptors (TLRs), and innate immune stimulation via TLRs affects melanin synthesis and melanosome transport to modulate skin pigmentation. TLR2 enhances melanogenetic gene expression to augment melanogenesis. In contrast, TLR3 increases melanosome transport to transfer to keratinocytes through Rab27A, the responsible molecule of Griscelli syndrome. TLR4 and TLR9 enhance tyrosinase expression and melanogenesis through p38 MAPK (mitogen-activated protein kinase) and NFκB signaling pathway, respectively. TLR7 suppresses microphthalmia-associated transcription factor (MITF), and MITF reduction leads to melanocyte apoptosis. Accumulating knowledge of the TLRs function of melanocytes has enlightened the link between melanogenesis and innate immune system.

scholarly journals Genetic Differentiation in Anthocyanin Content among Berry Fruits

2021 ◽  
Vol 43 (1) ◽  
pp. 36-51
Author(s):  
Alicja Ponder ◽  
Ewelina Hallmann ◽  
Martyna Kwolek ◽  
Dominika Średnicka-Tober ◽  
Renata Kazimierczak
Keyword(s):  
Essential Role ◽  
Positive Impact ◽  
Skin Pigmentation ◽  
Highbush Blueberry ◽  
Anthocyanin Content ◽  
Healthy Nutrition ◽  
Wide Range ◽  
Health Promoting ◽  
Berry Fruits ◽  
Red Currant

Anthocyanins are widely distributed secondary metabolites that play an essential role in skin pigmentation of many plant organs and microorganisms. Anthocyanins have been associated with a wide range of biological and pharmacological properties. They are also effective agents in the prevention and treatment of many chronic diseases. Berries are particularly abundant in these compounds; therefore, their dietary intake has health-promoting effects. The aim of this study was to identify and determine the anthocyanin content in selected species and cultivars of berry fruits, such as raspberry, blackberry, red currant, blackcurrant, and highbush blueberry, widely consumed by Europeans. The concentrations of anthocyanins were determined by HPLC, identifying individual compounds: cyanidin-3-O-glucoside, pelargonidin-3-O-glucoside, delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-rutinoside, delphinidin-3-O-galactoside, cyanidin-3-O-galactoside, and malvidin-3-O-galactoside. The experimental data showed that the selected species and cultivars of berry fruits differ significantly in the contents of anthocyanins. Among all species tested, blackberry and blackcurrant were characterized significantly by the highest content of anthocyanins (sum), while the lowest content was found in red currant fruits. Additionally, the content of individual anthocyanin compounds in particular species and cultivars was also different. Considering the high content of anthocyanins and their potential positive impact on human health and protection against disease, berries should be part of healthy nutrition.

scholarly journals Formation of Carbon Quantum Dots via Hydrothermal Carbonization: Investigate the Effect of Precursors

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 986
Author(s):  
Md Rifat Hasan ◽  
Nepu Saha ◽  
Thomas Quaid ◽  
M. Toufiq Reza
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Microcrystalline Cellulose ◽  
Uv Light ◽  
Synthesis Method ◽  
Hydrothermal Carbonization ◽  
Carbon Quantum Dots ◽  
Medical Diagnostics ◽  
Particle Size Range ◽  
Wide Range

Carbon quantum dots (CQDs) are nanomaterials with a particle size range of 2 to 10 nm. CQDs have a wide range of applications such as medical diagnostics, bio-imaging, biosensors, coatings, solar cells, and photocatalysis. Although the effect of various experimental parameters, such as the synthesis method, reaction time, etc., have been investigated, the effect of different feedstocks on CQDs has not been studied yet. In this study, CQDs were synthesized from hydroxymethylfurfural, furfural, and microcrystalline cellulose via hydrothermal carbonization at 220 °C for 30 min of residence time. The produced CQDs showed green luminescence behavior under the short-wavelength UV light. Furthermore, the optical properties of CQDs were investigated using ultraviolet-visible spectroscopy and emission spectrophotometer, while the morphology and chemical bonds of CQDs were investigated using transmission electron microscopy and Fourier-transform infrared spectroscopy, respectively. Results showed that all CQDs produced from various precursors have absorption and emission properties but these optical properties are highly dependent on the type of precursor. For instance, the mean particle sizes were 6.36 ± 0.54, 5.35 ± 0.56, and 3.94 ± 0.60 nm for the synthesized CQDs from microcrystalline cellulose, hydroxymethylfurfural, and furfural, respectively, which appeared to have similar trends in emission intensities. In addition, the synthesized CQDs experienced different functionality (e.g., C=O, O-H, C-O) resulting in different absorption behavior.

scholarly journals Photoprotection and Skin Pigmentation: Melanin-Related Molecules and Some Other New Agents Obtained from Natural Sources

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1537 ◽  
Author(s):  
Francisco Solano
Keyword(s):  
Human Skin ◽  
Uv Light ◽  
Stratospheric Ozone ◽  
Skin Pigmentation ◽  
Antioxidant Properties ◽  
Sun Exposure ◽  
Marine Organisms ◽  
Electromagnetic Spectrum ◽  
Chemical Structures ◽  
Skin Lightening

Direct sun exposure is one of the most aggressive factors for human skin. Sun radiation contains a range of the electromagnetic spectrum including UV light. In addition to the stratospheric ozone layer filtering the most harmful UVC, human skin contains a photoprotective pigment called melanin to protect from UVB, UVA, and blue visible light. This pigment is a redox UV-absorbing agent and functions as a shield to prevent direct UV action on the DNA of epidermal cells. In addition, melanin indirectly scavenges reactive oxygenated species (ROS) formed during the UV-inducing oxidative stress on the skin. The amounts of melanin in the skin depend on the phototype. In most phenotypes, endogenous melanin is not enough for full protection, especially in the summertime. Thus, photoprotective molecules should be added to commercial sunscreens. These molecules should show UV-absorbing capacity to complement the intrinsic photoprotection of the cutaneous natural pigment. This review deals with (a) the use of exogenous melanin or melanin-related compounds to mimic endogenous melanin and (b) the use of a number of natural compounds from plants and marine organisms that can act as UV filters and ROS scavengers. These agents have antioxidant properties, but this feature usually is associated to skin-lightening action. In contrast, good photoprotectors would be able to enhance natural cutaneous pigmentation. This review examines flavonoids, one of the main groups of these agents, as well as new promising compounds with other chemical structures recently obtained from marine organisms.

scholarly journals Effect of light on aggregational behavior of planarian Dugesia tigrina

2017 ◽  
Author(s):  
Jaemin Lee
Keyword(s):  
Defense Mechanisms ◽  
Uv Light ◽  
Infrared Light ◽  
Light Sources ◽  
Initial Exposure ◽  
Dugesia Tigrina ◽  
Wide Range ◽  
Photophobic Response ◽  
Negative Effect ◽  
Effect Of Light

Introduction. Planarians are renowned for their regenerative ability due to pluripotent stem cells, as well as their peculiar photophobic response. However, few facts are known about their aggregational behavior. This study aims to reveal the effect of light on aggregational behavior. Reynierse (1966) suggested that light has a negative effect on the formation of aggregations. However, one of his objectives for aggregational behavior was inappropriate. This study reevaluated the effect of existence of light on aggregational behavior, as well as ascertained the effect of wavelength on the formation of aggregations. Methods. In this study, the ratio of individuals participating in aggregations was measured as a criterion to determine aggregational behavior. Aggregational behavior was measured after two hours from the initial exposure to different light sources. The behaviors under white LED light and under shade were compared, as well as the behaviors under five different light sources: infrared lamp, red, green, blue LED, and ultraviolet lamp. Results. The existence of light interfered the formation of aggregations (t-test, p < 0.0001), which supports the former study of Reynierse. Also, aggregational behavior differed under different wavelengths (ANOVA, p < 0.0001). Except for the infrared light which emitted a wide range of wavelengths, the behavior showed hierarchy: decreasing aggregational behavior in accordance with decreasing wavelength. UV light has the most significant negative effect on the formation of aggregations. Discussion. Exposure to light caused negative effects on performing aggregational behavior. Participation in aggregations appears to be influenced by photophobic response, especially under lights of short wavelength. Disintegrating aggregations under exposure to lights can potentially bring evolutionary benefit. This behavior possibly makes the aggregating planarians altogether exposed to a higher risk or predation, considering that they lack defense mechanisms. Planarians can lower the risk and continue the populations by disintegrating the aggregational behavior under the existence of UV and lights of higher wavelength, which are indicatives of daytime. Understanding aggregational behavior of animals of a lower order would give better insight on general herding behavior, and potentially help interpreting more complex behaviors of higher animals.

Effects of Hydrophobic Barrier Films on the Mechanical Properties of Fiber Reinforced Composites Immersed in Water

2011 ◽  
Author(s):  
E. Kececi ◽  
R. Asmatulu
Keyword(s):  
Mechanical Properties ◽  
Moisture Absorption ◽  
Uv Light ◽  
Fiber Reinforced Composites ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Bending Tests ◽  
Barrier Films ◽  
Hydrophobic Barrier ◽  
Wide Range

Fiber reinforced composites are subjected to a wide range of mechanical loads and environmental conditions, such as wind, high/low temperature, moisture, UV light and aggressive solvents. Compared to other structural materials, polymers can absorb more moisture and UV light from outside environment and lose their material properties (e.g., mechanical, electrical, surface and thermal) and thus the service life. In this study, hydrophobic barrier films including polyvinylfluoride (PVF) and polyether ether ketone (PEEK) were applied on the carbon, Kevlar, and glass fiber reinforced epoxy resin composites (laminate and sandwich structures), and then the effects of moisture absorption on those films were investigated in detail. The coupons were immersed in water for a number of days in order to determine the changes in mechanical properties of the composites. Three point bending tests were applied to the laminate composites, while four point bending tests were conducted on the Nomex sandwich structured composites. We found that moisture absorption could be eliminated by using these hydrophobic films. We found that PEEK film could be an alternative barrier film for the aircraft industry.

Cytochemische Untersuchungen zur Reproduktion des Tabakmosaikvirus

1961 ◽  
Vol 16 (8) ◽  
pp. 520-538 ◽  
Author(s):  
Hendrik Zech
Keyword(s):  
Electric Fields ◽  
Uv Light ◽  
Refraction Index ◽  
Optical Measurements ◽  
Uv Spectrophotometry ◽  
X Rays ◽  
Optical Absorbance ◽  
Wide Range ◽  
Light Losses

Crystalline or paracrystalline tobacco mosaic virus (TMV) inclusions are known to be composed mainly of densely packed TMV-rods. These inclusions were studied in situ within infected tobacco leaf hair cells by scanning UV-microspectrophotometry. Comparative measurements in the macroand micro ranges of the instruments were carried out on purified TMV at low and high concentrations, on its separated and reconstituted RNA and protein parts and on isolated TMV-crystals, to permit the interpretation of the optical properties of TMV inclusions in situ. The optical absorbance of TMV in solution and in dried concentrates at room temperature could in part be attributed to distribution inhomogeneities caused by local particle aggregations being oriented to differing degrees. The resulting non-uniform electric fields around and within such unevenly distributed particle complexes caused local jumps of the refraction index and thereby unspecific light losses, chiefly through scattering. The apparent deviation from Beers law was found to be greatest at particle concentrations of 1 - 2 per cent. At higher concentrations the contribution of scatter to light losses was found to decrease again, probably because of increasing order of particles within the aggregates. On the other hand the specific absorbance of the chromophores of TMV over a wide range of concentration was not affected to a measurable degree by changing the distances between the rods. There was no indication that the charged groups of the RNA-cores within intact particles interacted with charged groups of other particles however great their proximity. The ribose phosphate backbone of the RNA strand, deeply embedded within the protein helix, may account for this phenomenon. However, isolated TMV-RNA reacted strongly to changes of the surrounding electric fields when concentrations were varied, and showed pronounced hypochromicity at higher concentrations and following prolonged irridation by x-rays and UV-light. RNA in dried and irradiated droplets was characterized by up to 55% lower extinction coefficients than freshly prepared RNA in solution. The hyprochromic effects caused by irradiation were shown to be almost, but not completely reversible. Hypochromicity increased towards the shorter wavelengths, diminishing the ratio E260/E280 from about 2.0 for diluted RNA to 1.4 for concentrated specimens. Mixing TMV-protein subunits with RNA before drying, leading to partial reconstitution of TMV particles, diminished the hypochromic effect resulting from irradiation of the concentrate. High UV-radiation doses applied to concentrated TMV solutions led to a marked splitting of RNA from protein, as revealed by UV-spectrophotometry of the supernatants and pellets of centrifuged irradiated specimens. Model measurements of intracellular and subsequently isolated TMV crystals combined with empirically derived parameters led to the construction of a correction curve, permitting interpretations of optical measurements on in situ TMV inclusion bodies.

Effect of 172-nm UV irradiation on polyimide and its application in surface modification by grafting

2020 ◽  
Vol 32 (7) ◽  
pp. 761-774
Author(s):  
Lopamudra Das ◽  
John C Poutsma ◽  
Michael J Kelley
Keyword(s):  
Uv Irradiation ◽  
Photoelectron Spectroscopy ◽  
Secondary Ion Mass Spectrometry ◽  
Mechanical Stability ◽  
Uv Light ◽  
Force Microscopy ◽  
Angle Measurements ◽  
Wide Range ◽  
Grafting Reactions ◽  
Sample Position

Polyimides (PIs) have a wide range of industrial and scientific applications due to their excellent thermal and mechanical stability and chemical resistance. Their response to ultraviolet (UV) irradiation is of further interest in high-value applications such as spacecraft technology and electronics packaging. In this work, we investigated the effect of 172-nm UV xenon excimer lamp irradiation on samples of pyromellitimido-oxydianiline (PMDA-ODA) commercial films in the absence of oxygen. The average irradiance received at the sample position was 90 mW/cm2, and the total radiation dosage varied from 0 to 64 J/cm2. X-Ray photoelectron spectroscopy, time-of-flight-secondary ion mass spectrometry, atomic force microscopy, and contact angle measurements were used to characterize the effect. Calculated UV-visible spectroscopy absorption spectra were obtained using the ZINDO//B3LYP/3-21G method to give an indication of which orbitals are involved in the transitions near 172 nm. The reactivity of the different UV-treated PI samples toward nitrogen-borne heptafluorodecene vapor was then investigated using the above techniques. Grafting reactions occurred on the surface of the photochemically activated polymer. This study explored the potential for modification of PI surfaces using UV-light-assisted grafting to impart valuable functionalities.

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