scholarly journals Ecological effects on female bill colour explain plastic sexual dichromatism in a mutually-ornamented bird

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rita Freitas ◽  
Cristiana Marques ◽  
Gonçalo C. Cardoso ◽  
Sandra Trigo
Keyword(s):  
Sex Differences ◽  
Vitamin E ◽  
Sexual Dichromatism ◽  
Social Functions ◽  
Reproductive Ability ◽  
Winter Cold ◽  
Female Investment ◽  
Colour Saturation ◽  
The Stability ◽  
Common Waxbill

AbstractSex differences in ornamentation are common and, in species with conventional sex roles, are generally thought of as stable, due to stronger sexual selection on males. Yet, especially in gregarious species, ornaments can also have non-sexual social functions, raising the possibility that observed sex differences in ornamentation are plastic. For example, females may invest in costly ornamentation more plastically, to protect body and reproductive ability in more adverse ecological conditions. We tested this hypothesis with experimental work on the mutually-ornamented common waxbill (Estrilda astrild), supplementing their diets either with pigmentary (lutein, a carotenoid) or non-pigmentary (vitamin E) antioxidants, or alleviating winter cold temperature. We found that both lutein and vitamin E supplementation increased red bill colour saturation in females, reaching the same mean saturation as males, which supports the hypothesis that female bill colour is more sensitive to environmental or physiological conditions. The effect of vitamin E, a non-pigment antioxidant, suggests that carotenoids were released from their antioxidant functions. Alleviating winter cold did not increase bill colour saturation in either sex, but increased the stability of female bill colour over time, suggesting that female investment in bill colour is sensitive to cold-mediated stress. Together, results show that waxbill bill sexual dichromatism is not stable. Instead, sexual dichromatism can be modulated, and even disappear completely, due to ecology-mediated plastic adjustments in female bill colour.

scholarly journals Ecological Effects on Female Bill Color Explain Plastic Sexual Dichromatism in A Mutually-Ornamented Bird

2021 ◽  
Author(s):  
Rita Freitas ◽  
Cristiana Marques ◽  
Gonçalo C. Cardoso ◽  
Sandra Trigo
Keyword(s):  
Sex Differences ◽  
Vitamin E ◽  
Sexual Dichromatism ◽  
Social Functions ◽  
Reproductive Ability ◽  
Winter Cold ◽  
Female Investment ◽  
Colour Saturation ◽  
The Stability ◽  
Common Waxbill

Abstract Sex differences in ornamentation are common and, in species with conventional sex roles, are generally thought of as fixed, due to stronger sexual selection on males. Yet, especially in gregarious species, ornaments can also have non-sexual social functions, raising the possibility that observed sex differences in ornamentation are not fixed. For example, females may invest in costly ornamentation more plastically, to protect body and reproductive ability in more adverse ecological conditions. We tested this hypothesis with experimental work on the mutually-ornamented common waxbill (Estrilda astrild), supplementing their diets either with pigment (lutein, a carotenoid) or non-pigment (vitamin E) antioxidants, or alleviating winter cold temperature. We found that both lutein and vitamin E supplementation increased red bill colour saturation in females, reaching the same mean saturation as males, which supports the hypothesis that female bill colour is more sensitive to environmental or physiological conditions. The effect of vitamin E, a non-pigment antioxidant, suggests that carotenoids were released from their antioxidant functions. Alleviating winter cold did not increase bill color saturation in either sex, but increased the stability of female bill color over time, suggesting that female investment in bill color is sensitive to cold-mediated stress. Together, results show that waxbill bill sexual dichromatism is not fixed. Instead, sexual dichromatism can be modulated, and even disappear completely, due to ecology-mediated plastic adjustments in female bill color.

Bromelain Encapsulated in Self Assembly Nanoemulsion Exhibits Better Debridement Effect in Animal Model of Burned Skin

2016 ◽  
Vol 40 ◽  
pp. 158-166 ◽  
Author(s):  
Heni Rachmawati ◽  
Evi Sulastri ◽  
Maria Immaculata Iwo ◽  
Dewi Safitri ◽  
Annisa Rahma
Keyword(s):  
Wound Healing ◽  
Animal Model ◽  
Vitamin E ◽  
Enzymatic Activity ◽  
Wound Contraction ◽  
Burn Treatment ◽  
Vitamin E Acetate ◽  
Burned Skin ◽  
Gel Preparation ◽  
The Stability

Bromelain is a mixture of proteolytic enzymes presence in all tissues of pineapple (Ananas comosus). It is known for clinical use as debridement for burn treatment. However, it is easily degraded by light, high temperature and pH. Nanoemulsion of bromelain is promising to increase its stability. In this study, we investigated the nanoemulsion of bromelain and its formulation into gel preparation in order to increase its efficacy for the burn treatment. Spontaneous or self-nanoemulsifying was applied to form nanoemulsion of bromelain (NEB). Bromelain was incorporated in various types of oil phase i.e virgin coconut oil (VCO), olive oil, vitamin E acetate and combination of both vitamin E acetate and VCO. Cremophor RH 40 was used together with polyethyleneglycol 400 to reduce oil-water interface tension. The stability of NEB in different oil phases was evaluated including particle size, polydispersity index, zeta potential, enzymatic activity and nanoemulsion morphology. Further, the most stable NEB was incorporated into hydrophilic gel matrix. An in vivo evaluation was carried out in hot plate-induced burn skin of New Zealand rabbit. Treatment of wounds was given by applying the preparations: NEB and the nanoemulsion bromelain-CMC gel (GKNB), using a standard protocol. As a control, untreated rabbit burned skin was provided. The efficacy of NEB was evaluated by observing wound contraction, eschar score, erythemic score, pus score and edema. After 14 days of storage, nanoemulsion using vitamin E acetate was found to be the most appropriate formula to encapsulate bromelain with good physical and chemical stabilities. This formula shows clear visual appearance with globule diameter of 74.37 nm, narrow size distribution, high loading efficiency of 97.96 %, and ability to maintain the enzymatic activity of bromelain compared to gel preparation using corresponding bromelain nanoemulsion. The vitamin E acetate nanoemulsion system shows better reduction in wound contraction until the 14th day of observation as well as other relevant parameters for wound healing effects. Taken together, bromelain formulated with the vitamin E acetate nanoemulsion improved the stability of bromelain and showed better activity to heal burnt skin on the animal model tested. The gel matrix retained the release of bromelain resulting in lower wound healing effect but it may have prolonged activity.

scholarly journals Effect of Dietary Vitamin E on the Stability and Sensory Quality of Turkey Meat

1983 ◽  
Vol 62 (7) ◽  
pp. 1224-1230 ◽  
Author(s):  
I. BARTOV ◽  
D. BASKER ◽  
S. ANGEL
Keyword(s):  
Vitamin E ◽  
Sensory Quality ◽  
Dietary Vitamin ◽  
Turkey Meat ◽  
The Stability

Effects of 3D Printing and Thermal Post Processing on the Stability of Vitamin E Acetate

2018 ◽  
Vol 118 (10) ◽  
pp. A148
Author(s):  
M. Scerra ◽  
A. Barrett ◽  
S. Eswaranandam ◽  
M. Okamoto
Keyword(s):  
Vitamin E ◽  
3D Printing ◽  
Post Processing ◽  
Vitamin E Acetate ◽  
The Stability

Effect of dietary Vitamin E on the stability of raw and cooked pork

Meat Science ◽  
1990 ◽  
Vol 27 (2) ◽  
pp. 99-108 ◽  
Author(s):  
F.J. Monahan ◽  
D.J. Buckley ◽  
J.I. Gray ◽  
P.A. Morrissey ◽  
A. Asghar ◽  
...  
Keyword(s):  
Vitamin E ◽  
Dietary Vitamin ◽  
The Stability

Stability and Sex Differences on the Coopersmith Self-Esteem Inventory for Students in Grades Two to Twelve

1977 ◽  
Vol 40 (3) ◽  
pp. 943-946 ◽  
Author(s):  
Robert J. Drummond ◽  
Walter G. McIntire ◽  
Charles W. Ryan
Keyword(s):  
Sex Differences ◽  
School District ◽  
Scale Score ◽  
Self Esteem ◽  
The Stability ◽  
Total Scale Score

This study reassessed the presence or absence of sex differences and investigated the stability of self-esteem as measured by Coopersmith's Self-esteem Inventory over 6 mo. for Grades 2 to 12. The subjects were 591 students, 296 male and 295 female, enrolled in an urban central Maine school district. No sex differences were found on any of the subscales or total scale score on either the pretest or posttests by grade. Significant correlations, small to moderate in size, were found for all grades on two scales, general self and total self. The results and implications are discussed.

Gas-Liquid Chromatographic Method for Determination of Fat-Soluble Vitamins. III. Evaluation of a Vacuum Distillation Procedure for Vitamin E Isolation, Using C-14 Labelled Alpha-Tocopheryl Acetate

1965 ◽  
Vol 48 (5) ◽  
pp. 977-980
Author(s):  
A J Sheppard ◽  
L A Ford ◽  
J W Boehne ◽  
D A Libby
Keyword(s):  
Vitamin E ◽  
Vacuum Distillation ◽  
Geiger Counter ◽  
Tocopheryl Acetate ◽  
Molecular Rearrangement ◽  
Liquid Scintillation Spectrometer ◽  
Carbon 14 ◽  
The Stability ◽  
Fat Soluble Vitamins ◽  
Liquid Chromatographic

Abstract Alpha-tocopheryl acetate, carbon-14 labelled in the methyl group at the two position, was used to determine the stability and recovery of the vitamin during vacuum distillation (140–160°C, and 0.020 mm Hg pressure, 60 minutes). Evaluation was based on measurements of radioactivity with a liquid scintillation spectrometer and a lowbackground Geiger counter. Recoveries of 20 mg of the pure compound were nearly quantitative (97%). Recoveries of the tocopheryl ester added to lard, “stripped” of vitamin E, at 0.5 mg/g or less and to butter at 0.1 mg/g were 98 and 82%, respectively. Results of the differential counting technique suggest that the ester is increasingly unstable at temperatures exceeding 160° and that a molecular rearrangement probably takes place.

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