scholarly journals Scale Thickness Predicts Skin Puncture-Force Resistance in Three Pleuronectiform Fishes

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
M R Minicozzi ◽  
J Perez ◽  
D S Kimball ◽  
A C Gibb

Synopsis In fishes, the skin and scales provide a physical barrier to the external environment and must withstand direct physical insult from biotic and abiotic features of the habitat. Flatfishes likely rely heavily on their scales for physical defense because they rest directly on the substrate. Using a flatfish model, we asked: what are the effects of scale type and scale morphology on puncture force resistance? We also asked: are there morphological and functional differences between the eyed and blind sides in flatfishes and do the morphological and functional properties of scales vary with organism size? Using a large size range of three species of Pleuronectid flatfish (Isopsetta isolepis, n = 10; Parophrys vetulus, n = 10; and Platichthys stellatus, n = 12), we measured the force required to puncture the integument using a sample of skin+scales taken from the eyed and blind side of each individual. We also measured the diameter, area, and thickness of the scales of each individual. Scaling relationships (body length vs. variable of interest) were derived for each species and compared with a priori expectations of geometric similarity. We found no relationship between scale type and puncture resistance and no differences in morphological parameters or puncture resistance between the eyed and blind side within a given species. These flatfish species do vary in their ability to withstand puncture forces; however, once scale thickness is taken into account, species differences disappear. Thus, the ability of a flatfish to withstand mechanical insult from puncture-forces varies depending on the thickness of the scale.

2013 ◽  
Vol 365-366 ◽  
pp. 1070-1073 ◽  
Author(s):  
Chia Chang Lin ◽  
Ting Ting Li ◽  
Ching Wen Lou ◽  
Jan Yi Lin ◽  
Jia Horng Lin

The dynamic puncture resistance of multi-layer integrated composite which was comprised of glass fabric reinforcement or Kevlar fabric reinforcement and nonwovens were discussed as related to recycled Kevlar fibers amount, number of layer and K-ply position for purpose of cost reduction and performance improvement. The result shows that, 20 wt% Kevlar fibers contained in nonwovens have the optimum puncture resistance. And the dynamic puncture force increases linearly with number of layers, and also improves proportionally as increasing number of K-ply. The resultant multi-layer composite is expected to be used as body armor interlayer and packaging materials.


2020 ◽  
Vol 90 (23-24) ◽  
pp. 2714-2726
Author(s):  
Xuanxuan Zhou ◽  
Wenfang Song ◽  
Yehu Lu

The very thin and lightweight silkworm cocoon has outstanding mechanical properties attributed to its specific composite microstructure. However, the microstructures of the cocoons have not been studied quantitatively, and their anti-puncture performance has not been examined as well. In this study, both domesticated ( Bombyx mori) and wild silkworm cocoons ( Antheraea pernyi, Antheraea mylitta and Samia canningi) were investigated for their microstructures using fractal theory, and their quasi-static puncture resistance was tested and compared. In addition, the effects of cocoon layers and hot-press treatments on the puncture resistance of two cocoon types ( B. mori and A. pernyi) were investigated. The three wild cocoons demonstrated significantly higher fractal dimensions, higher fiber intersectional densities and low porosities, indicating their structures are more optimized. They also displayed better puncture resistance than B. mori. Increased layer numbers could significantly increase the puncture resistance of both cocoon types and A. pernyi showed more remarkable increases. Moreover, the two cocoon types showed optimum puncture resistance after heat treatment with hot-press temperature of 135℃ and pressure of 25 MPa, and A. pernyi showed better puncture resistance after such treatment. Finally, both the maximum puncture force and puncture energy of cocoons displayed a linear increase with the increasing fractal dimensions. The new insights can guide the development of novel protective fiber composites with desirable and predictable anti-puncture performance.


2012 ◽  
Vol 7 (3) ◽  
pp. 155892501200700 ◽  
Author(s):  
Azadeh Seif Askari ◽  
Saeed Shaikhzadeh Najar ◽  
Yoness Alizadeh Vaghasloo

In this research, the effects of speed and weight on needlepunched nonwoven geotextiles subjected to CBR and Puncture tests were investigated. Polyester nonwoven fabrics with different weights (460, 715, 970 and 1070 g/m2) were prepared. The CBR test (ASTM D 6241) was conducted with five speeds, 25, 50, 75, 100 and 125 mm/min on geotextile layers, while the Puncture test (ASTM D 4833) was carried out at a standard speed of 300 mm/min on the same fabrics. Based on the load-elongation curves of these two tests, different puncture parameters, including puncture resistance (puncture force at failure), elongation at maximum force and puncture energy, were measured and statistically analyzed using ANOVA and multiple-range test methods. The results of the CBR tests indicate that the fabric weight significantly influenced the puncture resistance as well as the puncture energy and elongation while speed only affected the fabric puncture resistance and puncture energy. On the other hand, in the Puncture test, the fabric weight influenced all measured parameters.


1937 ◽  
Vol 3 (1) ◽  
pp. 12-19 ◽  
Author(s):  
Charles W. Lowe

An investigation to determine what species of diatoms are used as food by different species of copepods: Calanus tonsus, Euchaeta japonica, Metridia lucens, Harpacticus uniremis, and Diosaccus spinatus. Also to determine the food chains between diatoms, copepods, and the following fish: Pacific herring, Clupea pallasii; chum salmon, Oncorhynchus keta; spring salmon, O. tschawytscha; dogfish, Squalus suckleyi; ling cod, Ophiodon elongatus; rockfish, Sebastodes caurinus; starry flounder, Platichthys stellatus; lemon sole, Parophrys vetulus; yellow-finned surffish, Damalichthys vacca; blue perch, Taeniotoca lateralis, and yellow shiner, Cymatogaster aggregatus. Stomach, intestines, and excreta were examined for the presence of diatoms. Almost all the common diatoms were found to be used as food by the copepods. The copepods and herring were found to be important links in the food chains between diatoms and the larger fishes.


1964 ◽  
Vol 21 (4) ◽  
pp. 765-771 ◽  
Author(s):  
E. Bilinski

An in-vivo study was made of potential precursors of trimethylamine oxide (TMAO) in marine teleosts (lemon sole, Parophrys vetulus, and starry flounder, Platichthys stellatus). C14-labelled compounds were administered intraperitoneally and the incorporation of tracer into TMAO, isolated from the whole body, was determined. Trimethylamine (TMA)-C14 was found to be a much better precursor than the other compounds tested. A limited labelling of TMAO was observed after administration of γ-butyrobetaine-methyl-C14, betaine-methyl-C14 and methionine-methyl-C14. There was little or no incorporation of C14 into TMAO after administration of methylamine-C14, carnitine-methyl-C14, gIycine-2-C14, sodium formate-C14, sodium acetate-1-C14, sodium acetate-2-C14 and NaHCO3-C14. The conversion of choline-methyl-C14 to TMAO was higher after intraperitoneal than after intramuscular injection and only trace amounts of radioactivity were found after intravenous injection. The results provide support for formation of TMAO in fish by oxidation of TMA but they give no clear indication for metabolic pathways leading to this oxidative step.Betaine was isolated from fish after administration of choline-methyl-C14, methionine-methyl-C14 and glycine-2-C14. Evidence of extensive conversion of choline to betaine was obtained. Betaine also was found to be labelled after administration of methionine-methyl-C14, but only a limited degree of labelling was observed after administration of glycine-2-C14. The results indicate that betaine is formed by oxidation of choline in fish.A modification of the Dragendorff reagent for use as a spray for detecting trimethylammonium compounds on paper chromatograms is described.


2014 ◽  
Vol 18 (2) ◽  
pp. 79-87 ◽  
Author(s):  
Duk-Young Kang ◽  
Soon-Gyu Byun ◽  
Jeong-In Myeong ◽  
Hyo-Chan Kim ◽  
Byoung-Hwa Min

1976 ◽  
Vol 33 (11) ◽  
pp. 2577-2586 ◽  
Author(s):  
S. R. Wellings ◽  
C. E. Alpers ◽  
B. B. McCain ◽  
B. S. Miller

Fin erosion in the starry flounder (Platichthys stellatus) and English sole (Parophrys vetulus) of the Duwamish River, Washington, is characterized by ulcerating chronic inflammation and fibrosis with resorption of fin rays. The end result is deformation, shortening, and retraction of residual fin tissue with loss of functional surface. We suggest that the incidence of fin erosion in a particular population is related to an interaction between genetic constitution and multiple environmental variables, including a variety of chemical pollutants.


1971 ◽  
Vol 28 (9) ◽  
pp. 1241-1251 ◽  
Author(s):  
G. E. McArn ◽  
S. R. Wellings

A study of the natural history of skin tumors occurring on two species of Pleuronectidae was conducted in the waters of Bellingham Bay, Washington. Twelve collections at monthly intervals indicated that 4.8% of 1977 English sole (Parophrys vetulus) and 2.4% of 2946 starry flounders (Platichthys stellatus) were tumorous. Three types of tumors were observed, and were classified as angioepithelial nodules, epidermal papillomas, or angioepithelial polyps, according to nomenclature previously established by other workers. The angioepithelial nodule was found on fish in the 1st year of life but not on fish older than 1 year. Epidermal papillomas usually occurred on fish that were 1 year or older, as did the angioepithelial polyps. The incidence of tumor-bearing fish, and the average number of tumors on a single specimen was greatest during the 1st year of life and decreased progressively in older age-groups. Tumors were more likely to occur on the pigmented side than on the nonpigmented side of the fish. The results of this study were compared and contrasted with a similar disease previously described on Hippoglossoides elassodon, the flathead sole.


Sign in / Sign up

Export Citation Format

Share Document