Why arboreal snakes should not be cylindrical: body shape, incline and surface roughness have interactive effects on locomotion

2015 ◽  
Vol 218 (24) ◽  
pp. 3978-3986 ◽  
Author(s):  
B. C. Jayne ◽  
S. J. Newman ◽  
M. M. Zentkovich ◽  
H. M. Berns
Keyword(s):  
Surface Roughness ◽  
Body Shape ◽  
Cylindrical Body ◽  
Interactive Effects ◽  
Arboreal Snakes

Chaos in body–vortex interactions

2010 ◽  
Vol 466 (2119) ◽  
pp. 1871-1891 ◽  
Author(s):  
Johan Roenby ◽  
Hassan Aref
Keyword(s):  
Body Shape ◽  
Mass Density ◽  
Relative Equilibrium ◽  
Large Body ◽  
Point Vortex ◽  
Cylindrical Body ◽  
The Body ◽  
Body Motion ◽  
Single Vortex ◽  
Vortex Interactions

The model of body–vortex interactions, where the fluid flow is planar, ideal and unbounded, and the vortex is a point vortex, is studied. The body may have a constant circulation around it. The governing equations for the general case of a freely moving body of arbitrary shape and mass density and an arbitrary number of point vortices are presented. The case of a body and a single vortex is then investigated numerically in detail. In this paper, the body is a homogeneous, elliptical cylinder. For large body–vortex separations, the system behaves much like a vortex pair regardless of body shape. The case of a circle is integrable. As the body is made slightly elliptic, a chaotic region grows from an unstable relative equilibrium of the circle-vortex case. The case of a cylindrical body of any shape moving in fluid otherwise at rest is also integrable. A second transition to chaos arises from the limit between rocking and tumbling motion of the body known in this case. In both instances, the chaos may be detected both in the body motion and in the vortex motion. The effect of increasing body mass at a fixed body shape is to damp the chaos.

I can’t stop looking at them: Interactive effects of body mass index and weight dissatisfaction on attention towards body shape photographs

Body Image ◽  
2013 ◽  
Vol 10 (2) ◽  
pp. 191-199 ◽  
Author(s):  
Xiao Gao ◽  
Xiaojing Li ◽  
Xiaoying Yang ◽  
Yang Wang ◽  
Todd Jackson ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Body Shape ◽  
Interactive Effects

scholarly journals IDENTIFIKASI DAN PREVALENSI ENDOPARASIT (Gnathostoma sp.) PADA BELUT SAWAH (Monopterus albus) DENGAN UKURAN BERBEDA YANG DIKIRIM KELUAR PROVINSI KALIMANTAN SELATAN

2021 ◽  
Vol 46 (3) ◽  
pp. 352
Author(s):  
Lukman Mugiyarto ◽  
Elrifadah Elrifadah ◽  
Mukhlisah Mukhlisah
Keyword(s):  
Body Shape ◽  
Rice Field ◽  
Morphological Characteristics ◽  
Cylindrical Body ◽  
Head Shape ◽  
Monopterus Albus ◽  
Rice Field Eel ◽  
Third Stage ◽  
Value Range ◽  
Descriptive Method

This study aims to determine the type of endoparasitic worm Gnathostoma sp and the prevalence that infects rice field eel (Monopterus albus) with different grades. the method used is the descriptive method. Samples were taken from 3 different farm locations (Nor Aini, Banjar Regency, CV. Karya Bersama, Banjarbaru City, and Saberiannor Banjarbaru City), as many as 120 individuals with each grade (A, B, C, and D) totaling 30 individuals. Samples were examined using the microscopic method with 3 replications on each target organ, namely liver, meat, intestines, and kidneys. The results of the examination showed that Gnathostoma sp worm cysts were found, namely only in the liver, while in the intestines, flesh, and kidneys were not found. Based on the identification of Gnathostoma sp endoparasites seen from morphological characteristics, third-stage larvae (L3) in the phylum Nematoda, cylindrical body shape, transparent body color, and blackish brown, head shape resembling a light bulb, mouth, and has anus at the end of its body. Prevalence value in grade A = 40%; B= 30%; C= 40%, and D= 30%, this includes the category commonly or ordinary which describes that the parasite usually infects fish with a prevalence value range of 30-49%.          It is still possible to send rice field eels outside of South Kalimantan Province, although the results of the examination of the test samples indicated the presence of the parasite infection Gnathostoma sp..

scholarly journals Evaluation of the Bonding Strength between Various Dental Zirconia Models and Human Teeth for Dental Posts through In Vitro Aging Tests

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1017
Author(s):  
Shih-Chieh Lin ◽  
Wei-Chun Lin ◽  
Tai-Chia Hu ◽  
Min Yan ◽  
Cheng-Ming Tang
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Bond Strength ◽  
Bonding Strength ◽  
Aging Treatment ◽  
Cylindrical Body ◽  
Surface Characteristics ◽  
Light Transmittance ◽  
Human Teeth

In dentistry, root canal treatment reduces support of the tooth, making it necessary to insert a cylindrical body into the treated tooth to strengthen the crown. In the past, metal or fiberglass was often used. However, metal is too different in color from teeth, so the esthetics are poor, and fiberglass is not as strong as metal. Therefore, an alternative is zirconia, which has the characteristics of high light transmittance, esthetics, good biocompatibility, and high breaking strength. The surface morphology and composition of zirconia ceramics are the key to their bond strength with teeth. Therefore, in this study, the surface characteristics of different brands of zirconia commonly used in clinical practice were evaluated in terms of their surface morphology and surface elements. The surface was modified by sandblasting, and its effect on the bonding strength was discussed. Finally, the stability of the material was evaluated through artificial aging. The results showed that the surface roughness of the zirconia specimens increased after sandblasting, whereas the surface microhardness decreased. The shear test results showed that the 3D shape of the zirconia surface could help improve the bonding strength. The bonding strength of DeguDent increased the most after sandblasting. After 20,000 cycles of aging treatment, the shear strength of each specimen decreased. Field emission scanning electron microscopy results showed that the adhesive remained intact on the surface of zirconia, indicating that adhesion failure occurred between the adhesive and the teeth. This confirms that sandblasting can improve the bonding strength of zirconia. Based on the results obtained, it was concluded that the surface roughness of zirconia is the main factor affecting the bond strength.

Two new species of Paramphiascella Lang (Copepoda: Harpacticoida: Miraciidae) from a brackish water pond in Thailand

Zootaxa ◽  
2010 ◽  
Vol 2634 (1) ◽  
pp. 1
Author(s):  
SUPAWADEE CHULLASORN
Keyword(s):  
New Species ◽  
Brackish Water ◽  
Body Shape ◽  
Cylindrical Body ◽  
Research Development ◽  
Coastal Fisheries ◽  
Two New Species ◽  
Water Pond ◽  
Brackish Water Pond ◽  
Development Center

Two new species of the harpacticoid genus Paramphiascella Lang, 1944 were collected from a brackish water pond located at the Coastal Fisheries Research Development Center, Department of Fisheries, Samut Sakhon province, Thailand, and are described herein. Paramphiascella dahmsi sp. nov. and P. ferrarii sp. nov. are similar to other species of the genus in having a cylindrical body shape, eight-segmented antennules, and both the baseoendopod and exopod of the female P5 with five setae. However, the two new species can be distinguished from other congeners by having one big ovate-striated knob at the inner edge of the male P1 basis. Paramphiascella dahmsi bears in addition two ovatestriated knobs on the anterior surface of the proximal rim of the male P1 Enp1 while P. ferrarii is without any knobs on the endopod. The Enp2 of male P2 of P. dahmsi is distally attenuated, with a medially pointed knob close to Enp1. Adjacent to the knob there are two setae, one spinulose and one pectinate, and one club-like seta bifurcate at its tip. In P. ferrarii, the medial knob is rounded, a second long attenuation arises near the base of two unequal spinulose setae and the club-like seta is absent. In addition, the P2 Enp1 bears an inner spinulose seta in P. dahmsi, while in P. ferrarii it bears a pectinate seta. These characters are suggested as autapomorphies of the new species.

scholarly journals The role of turbulent hydrodynamics and surface morphology on heat and mass transfer in corals

2018 ◽  
Vol 15 (149) ◽  
pp. 20180448 ◽  
Author(s):  
Jonathan B. Stocking ◽  
Christian Laforsch ◽  
Robert Sigl ◽  
Matthew A. Reidenbach
Keyword(s):  
Mass Transfer ◽  
Surface Roughness ◽  
Thermal Stress ◽  
Heat And Mass Transfer ◽  
Global Climate ◽  
Interactive Effects ◽  
Hydrodynamic Characteristics ◽  
Overlying Water ◽  
Small Surface ◽  
Transfer Rates

Corals require efficient heat and mass transfer with the overlying water column to support key biological processes, such as nutrient uptake and mitigation of thermal stress. Transfer rates are primarily determined by flow conditions, coral morphology and the physics of the resulting fluid–structure interaction, yet the relationship among these parameters is poorly understood especially for wave-dominated coral habitats. To investigate the interactive effects of these factors on fluxes of heat and mass, we measure hydrodynamic characteristics in situ over three distinct surface morphologies of massive stony corals in a Panamanian reef. Additionally, we implement a numerical model of flow and thermal transport for both current and wave conditions past a natural coral surface, as well as past three simplified coral morphologies with varying ratios of surface roughness spacing-to-height. We find oscillatory flow enhances rates of heat and mass transfer by 1.2–2.0× compared with unidirectional flow. Additionally, increases in Reynolds number and in surface roughness ratio produce up to a 3.3× and a 2.0× enhancement, respectively. However, as waves begin to dominate the flow regime relative to unidirectional currents, the underlying physical mechanisms mediating transfer rates shift from predominantly turbulence-driven to greater control by inertial accelerations, resulting in larger heat and mass transfer for small surface roughness ratios. We show that for rough corals in wave-dominated flows, novel trade-off dynamics for heat and mass transfer exist between broadly spaced roughness that enhances turbulence production versus narrowly spaced roughness that produces greater surface area. These findings have important implications for differential survivorship during heat-induced coral bleaching, particularly as thermal stress events become increasingly common with global climate change.

A hump-shaped relationship between migration distance and adult pink salmon morphology suggests interactive effects of migration costs and bear predation

2016 ◽  
Vol 73 (3) ◽  
pp. 427-435 ◽  
Author(s):  
Genki Sahashi ◽  
Taku Yoshiyama
Keyword(s):  
Body Shape ◽  
Pink Salmon ◽  
Interactive Effects ◽  
Head Size ◽  
Oncorhynchus Gorbuscha ◽  
Spawning Habitat ◽  
Selective Predation ◽  
Body Depth ◽  
Shape Selective ◽  
Migration Costs

We examined the relationship between environmental factors of a spawning habitat and body shape at maturity in 16 pink salmon (Oncorhynchus gorbuscha) populations. The divergence vector (indicator of body depth and head size development) in both sexes was significantly correlated with distance from the sea and was described by a hump-shaped relationship. An exaggerated body shape was most developed at mid-distance from the sea and less developed both near and far from the sea. The observed frequency of bears decreased significantly with distance from the sea, implying that bear predation on salmon is most intense near the sea. Therefore, our results imply that shape-selective predation by bears affects the shape of pink salmon in rivers where the spawning habitat is near the sea and that migration costs inhibit development of an exaggerated body depth and head size in salmon in rivers where the spawning habitat is far from the sea.

scholarly journals Interactive Effects of Rarefaction and Surface Roughness on Aerodynamic Lubrication of Microbearings

Micromachines ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 155 ◽  
Author(s):  
Yao Wu ◽  
Lihua Yang ◽  
Tengfei Xu ◽  
Haoliang Xu
Keyword(s):  
Surface Roughness ◽  
Reynolds Equation ◽  
Interactive Effects ◽  
Correction Model ◽  
Operation Conditions ◽  
Damping Characteristics ◽  
Lubrication Performance ◽  
Fractal Roughness ◽  
The Stability ◽  
Bearing Number

The aerodynamic lubrication performance of gas microbearing has a particularly critical impact on the stability of the bearing-rotor system in micromachines. Based on the Duwensee’s slip correction model and the fractal geometry theory, the interactive effects of gas rarefaction and surface roughness on the static and dynamic characteristics were investigated under various operation conditions and structure parameters. The modified Reynolds equation, which governs the gas film pressure distribution in rough bearing, is solved by employing the partial derivative method. The results show that high values of the eccentricity ratio and bearing number tend to increase the principal stiffness coefficients significantly, and the fractal roughness surface considerably affects the ultra-thin film damping characteristics compared to smooth surface bearing.

SevenAcantholaimus(Chromadoridae: Nematoda) species from one deep-sea sediment sample (Angola Basin, south-east Atlantic)

2012 ◽  
Vol 93 (4) ◽  
pp. 935-953 ◽  
Author(s):  
Maria A. Miljutina ◽  
Dmitry M. Miljutin ◽  
Alexei V. Tchesunov
Keyword(s):  
Deep Sea ◽  
Body Shape ◽  
Cylindrical Body ◽  
The Body ◽  
East Atlantic ◽  
Deep Sea Sediment ◽  
The Pacific ◽  
Kenyan Coast ◽  
The Indian Ocean ◽  
Previous Location

The genusAcantholaimus(Chromadoridae: Nematoda) is one of the most species-rich deep-sea nematode genera. The descriptions of two new species and supplemental descriptions of five known species from the Angola Basin (south-east Atlantic Ocean) and a depth of about 5500 m are given.Acantholaimus formosussp. nov. is characterized by a spindle-shaped body with narrow elongated anterior end, the position of amphideal fovea on the apical tip of the body and by robust rugae and onchia.Acantholaimus skukinaesp. nov. is characterized by its cylindrical body shape; short outer labial, cephalic, cervical, and somatic setae; large amphideal fovea; the position of its amphideal fovea (situated relatively far from the head end); and relatively small onchia.Acantholaimus angustuswas previously found in the Peru Basin (central-eastern Pacific) and the Clarion–Clipperton Nodule Province (Equatorial Pacific), about 13,000 km apart from the nearest previous location of finding. The type location ofA. verscheldiis the Kenyan coast of the Indian Ocean. New specimens of this species were found about 8000 km apart from the type location.Acantholaimus akvavitus, A. iubilusandA. quintuswere previously found in different parts of the Atlantic and the Pacific.

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