scholarly journals Fluid and Predator-Prey Interactions of Scyphomedusae Fed Calanoid Copepods

Fluids ◽  
2020 ◽  
Vol 5 (2) ◽  
pp. 60
Author(s):  
Zachary Wagner ◽  
John H. Costello ◽  
Sean P. Colin
Keyword(s):  
Surface Morphology ◽  
Prey Size ◽  
Capture Efficiency ◽  
Calanoid Copepods ◽  
Fluid Shear ◽  
Predator Prey ◽  
Prey Behavior ◽  
Feeding Process ◽  
And Behavior ◽  
Surface Morphologies

The feeding current of scyphomedusae entrains and transports surrounding fluids and prey through trailing tentacles to initiate encounters with prey. After contact, most prey are retained for ingestion. However, the probability that a contact will occur depends on several factors including capture surface morphology, prey size and behavior. We examined how hydrodynamics, capture surface morphology and prey behavior affect the capture probability of copepods. To do this, we documented medusa-copepod interactions of four species of scyphomedusae (two semeostomes and two rhizostomes) possessing different capture surface morphologies. We tracked the movement and behavior of entrained copepods throughout the feeding process to quantify prey behavior effects upon capture efficiency (# captures/# encounters). The feeding currents generated by all the medusan species generated fluid shear deformation rates well above the detection limits of copepods. Despite strong hydrodynamic signals, copepod behavior was highly variable and only 58% of the copepods reacted to entrainment within feeding currents. Furthermore, copepod behavior (categorized as no reaction, escape jump or adjustment jump) did not significantly affect the capture efficiency. The scale and complexity of the feeding current generated by scyphomedusae may help explain the poor ability of copepods to avoid capture.

Effect of Substratum Morphology on Animal Cell Adhesion and Behavior

1991 ◽  
Vol 252 ◽  
Author(s):  
Rahul Singhvi ◽  
Gregory N. Stephanopoulos ◽  
Daniel I. C. Wang
Keyword(s):  
Cell Adhesion ◽  
Surface Morphology ◽  
Animal Cell ◽  
Recombinant Cell Line ◽  
A Cell ◽  
Recombinant Cell ◽  
And Function ◽  
Glass Surfaces ◽  
And Behavior ◽  
Surface Morphologies

ABSTRACTGlass surfaces with well defined surface morphologies have been prepared using photolithography to study the effect of surface morphology on cell adhesion and function. Using a transformed recombinant cell-line, AtT-20, as a model of shear sensitive cell, we have shown that cell-substratum adhesion strength is enhanced using a surface with uniform grooves without any loss in cellular function. Furthermore, using primary hepatocytes as a model for a cell whose function is sensitive to its shape, we have shown that surface morphology can modulate cell shape as well as its function.

Defect morphology in thick relaxed layers of InGaAs on GaAs

1990 ◽  
Vol 48 (4) ◽  
pp. 668-669
Author(s):  
R H Dixon ◽  
P Kidd ◽  
P J Goodhew
Keyword(s):  
Electron Microscopy ◽  
Surface Morphology ◽  
Growth Conditions ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
Strained Layers ◽  
Good Surface ◽  
Transmission Electron ◽  
Device Structures ◽  
Surface Morphologies

Thick relaxed InGaAs layers grown epitaxially on GaAs are potentially useful substrates for growing high indium percentage strained layers. It is important that these relaxed layers are defect free and have a good surface morphology for the subsequent growth of device structures.3μm relaxed layers of InxGa1-xAs were grown on semi - insulating GaAs substrates by Molecular Beam Epitaxy (MBE), where the indium composition ranged from x=0.1 to 1.0. The interface, bulk and surface of the layers have been examined in planar view and cross-section by Transmission Electron Microscopy (TEM). The surface morphologies have been characterised by Scanning Electron Microscopy (SEM), and the bulk lattice perfection of the layers assessed using Double Crystal X-ray Diffraction (DCXRD).The surface morphology has been found to correlate with the growth conditions, with the type of defects grown-in to the layer (e.g. stacking faults, microtwins), and with the nature and density of dislocations in the interface.

In Vivo and In Vitro Evaluation of Coated HAp Films with Different Surface Morphology

2007 ◽  
Vol 539-543 ◽  
pp. 710-715
Author(s):  
Kotaro Kuroda ◽  
Ryoichi Ichino ◽  
Masazumi Okido
Keyword(s):  
Bone Formation ◽  
Surface Morphology ◽  
New Bone Formation ◽  
Contact Ratio ◽  
Bone Implant ◽  
Ft Ir ◽  
Mouse Osteoblast ◽  
Surface Morphologies

Hydroxyapatite (HAp) coatings were formed on cp titanium plates and rods by the thermal substrate method in an aqueous solution that included 0.3 mM Ca(H2PO4)2 and 0.7 mM CaCl2. The coating experiments were conducted at 40-140 oC and pH = 8 for 15 or 30 min. The properties for the coated samples were studied using XRD, EDX, FT-IR, and SEM. All the specimens were covered with HAp, which had different surface morphologies such as net-like, plate-like and needle-like. After cleaning and sterilization, all the coated specimens were subjected to in vivo and vitro testing. In the in vitro testing, the mouse osteoblast-like cells (MC3T3-E1) were cultured on the coated and non-coated specimens for up to 30 days. Moreover, the specimens (φ2 x 5 mm) were implanted in rats femoral for up to 8 weeks, the osseoinductivity on them were evaluated. In in vitro evaluations, there were not significant differences between the different surface morphologies. In in vivo evaluations, however, two weeks postimplantation, new bone formed on both the HAp coated and non-coated titanium rods in the cancellous and cortical bone. The bone-implant contact ratio, which was used for the evaluation of new bone formation, was significantly dependent on the surface morphology of the HAp, and the results demonstrated that the needle-like coating appears to promote rapid bone formation.

Study on Electrodeposition of Ni-Graphite Composite Coatings in Sulfamate Bath

2010 ◽  
Vol 150-151 ◽  
pp. 1546-1550 ◽  
Author(s):  
Xiang Zhu He ◽  
Xiao Wei Zhang ◽  
Xin Li Zhou ◽  
Zhi Hong Fu
Keyword(s):  
Surface Morphology ◽  
Process Parameters ◽  
Current Density ◽  
Graphite Particle ◽  
Particle Concentration ◽  
Composite Coatings ◽  
Nickel Matrix ◽  
Graphite Composite ◽  
Surface Morphologies ◽  
Sulfamate Bath

This paper presented the composite coatings of nickel with graphite particle on the aluminum substrate using a nickel sulfamate bath. Effects of graphite particle concentration on the surface morphologies of the composite coatings were investigated. The inclusion of graphite particle into metal deposits was dependent on many process parameters, including particle concentration, current density, pH and temperature. Results of SEM and XRD demonstrated that graphite particle had successfully deposited on that nickel matrix; besides, the surface morphology of coatings obtained from sulfamate bath containing 2g/L graphite particle dispersed more uniformly than the ones with higher concentration.

scholarly journals The mechanics of predator–prey interactions: First principles of physics predict predator–prey size ratios

2018 ◽  
Vol 33 (2) ◽  
pp. 323-334 ◽  
Author(s):  
Sébastien M. J. Portalier ◽  
Gregor F. Fussmann ◽  
Michel Loreau ◽  
Mehdi Cherif
Keyword(s):  
First Principles ◽  
Prey Size ◽  
Predator Prey

scholarly journals The impact of large terrestrial carnivores on Pleistocene ecosystems

2015 ◽  
Vol 113 (4) ◽  
pp. 862-867 ◽  
Author(s):  
Blaire Van Valkenburgh ◽  
Matthew W. Hayward ◽  
William J. Ripple ◽  
Carlo Meloro ◽  
V. Louise Roth
Keyword(s):  
Prey Size ◽  
Habitat Degradation ◽  
Terrestrial Ecosystems ◽  
Growth Data ◽  
Predator Prey ◽  
Body Sizes ◽  
Population Sizes ◽  
Potential Impact ◽  
The Impact ◽  
Ground Sloths

Large mammalian terrestrial herbivores, such as elephants, have dramatic effects on the ecosystems they inhabit and at high population densities their environmental impacts can be devastating. Pleistocene terrestrial ecosystems included a much greater diversity of megaherbivores (e.g., mammoths, mastodons, giant ground sloths) and thus a greater potential for widespread habitat degradation if population sizes were not limited. Nevertheless, based on modern observations, it is generally believed that populations of megaherbivores (>800 kg) are largely immune to the effects of predation and this perception has been extended into the Pleistocene. However, as shown here, the species richness of big carnivores was greater in the Pleistocene and many of them were significantly larger than their modern counterparts. Fossil evidence suggests that interspecific competition among carnivores was relatively intense and reveals that some individuals specialized in consuming megaherbivores. To estimate the potential impact of Pleistocene large carnivores, we use both historic and modern data on predator–prey body mass relationships to predict size ranges of their typical and maximum prey when hunting as individuals and in groups. These prey size ranges are then compared with estimates of juvenile and subadult proboscidean body sizes derived from extant elephant growth data. Young proboscideans at their most vulnerable age fall within the predicted prey size ranges of many of the Pleistocene carnivores. Predation on juveniles can have a greater impact on megaherbivores because of their long interbirth intervals, and consequently, we argue that Pleistocene carnivores had the capacity to, and likely did, limit megaherbivore population sizes.

Warming-induced shifts in amphibian phenology and behavior lead to altered predator–prey dynamics

Oecologia ◽  
2019 ◽  
Vol 189 (3) ◽  
pp. 803-813 ◽  
Author(s):  
Fabian G. Jara ◽  
Lindsey L. Thurman ◽  
Pierre-Olivier Montiglio ◽  
Andrew Sih ◽  
Tiffany S. Garcia
Keyword(s):  
Predator Prey ◽  
And Behavior

Atomic oxygen effects on polymers containing silicon or phosphorus: Mass loss, erosion yield, and surface morphology

2018 ◽  
Vol 31 (8) ◽  
pp. 969-976 ◽  
Author(s):  
Wang Chunbo ◽  
Jiang Haifu ◽  
Tian Dongbo ◽  
Qin Wei ◽  
Chen Chunhai ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Mass Loss ◽  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Relative Order ◽  
Oxygen Effects ◽  
Arylene Ether ◽  
Inorganic Coatings ◽  
Oligomeric Silsesquioxane ◽  
Surface Morphologies

The differences among polymers containing silicon or phosphorus, 20% polyhedral oligomeric silsesquioxane polyimide (20%-POSS-PI), 30% polysiloxane- block-polyimides (30%-PSX-PI), poly(siloxane imide) homopolymer (PSX-PI), and arylene ether phosphine oxide homopolymer (P-PPO), on mass loss, erosion yield, and surface morphology were elucidated. The tolerance against atomic oxygen (AO) was improved versus Kapton®H after introducing silicon or phosphorus to the polymers. The relative order of the mass loss was PSX-PI < P-PPO < 20%-POSS-PI < 30%-PSX-PI. In contrast, the erosion yields of 30%-PSX-PI, 20%-POSS-PI, and P-PPO decreased by orders of magnitude (PSX-PI declined by about two orders). The surface of Kapton®H was seriously eroded by AO exhibiting a “carpet-like” shape, and the roughness of the surface of Kapton®H became remarkable as the AO fluence increased. PSX-PI, P-PPO, 20%-POSS-PI, and 30%-PSX-PI at an AO fluence of 5.2 × 1020 atoms/cm2 had different surface morphologies, and the relative order of the surface roughness was PSX-PI < 30%-PSX-PI < 20%-POSS-PI < P-PPO. The 30%-PSX-PI and PSX-PI had minor mass losses and a smooth surface. This kind of material might replace inorganic coatings for applications in low earth orbit.

First fecundity observations on female copepods from three northern Patagonian lakes (Pellaifa, Calafquén, Panguipulli; Chile)

Crustaceana ◽  
2019 ◽  
Vol 92 (8) ◽  
pp. 897-905
Author(s):  
Patricio De los Ríos ◽  
Jorge Farias-Avendaño ◽  
Maria J. Suazo
Keyword(s):  
Community Structure ◽  
Interspecific Competition ◽  
Crustacean Zooplankton ◽  
Calanoid Copepods ◽  
Predator Prey ◽  
Total Length ◽  
Patagonian Lakes ◽  
Egg Number

Abstract The crustacean zooplankton in Chilean Patagonian lakes is characterized by a marked dominance of calanoid copepods when under an oligotrophic status. The aim of the present study was to analyse the number of eggs and the relation of that feature with the total length of females of calanoid and cyclopoid copepods reported in three northern Chilean Patagonian lakes. The calanoid copepods found were Boeckella gracilipes in Lake Pellaifa and Tumeodiaptomus diabolicus in the lakes Panguipulli and Calafquén, whereas the cyclopoid Mesocyclops araucanus was found in the lakes Pellaifa and Calafquén. For calanoid copepods, high egg numbers were found and thus also a high value for the ratio of egg number per female length in Lake Panguipulli, whereas for M. araucanus a high value was found in Lake Pellaifa. These differences would presumably be associated with community structure, specifically predator-prey relationships and possibly other interactions, as, e.g., potential interspecific competition.

scholarly journals A Novel Method to Achieve Selective Emitter Using Surface Morphology for PERC Silicon Solar Cells

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5207
Author(s):  
Minkyu Ju ◽  
Jeongeun Park ◽  
Young Hyun Cho ◽  
Youngkuk Kim ◽  
Donggun Lim ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Sheet Resistance ◽  
Conversion Efficiency ◽  
Single Step ◽  
Process Conditions ◽  
Selective Emitter ◽  
Driving Time ◽  
Novel Method ◽  
The Difference ◽  
Surface Morphologies

Recently, selective emitter (SE) technology has attracted renewed attention in the Si solar cell industry to achieve an improved conversion efficiency of passivated-emitter rear-contact (PERC) cells. In this study, we presented a novel technique for the SE formation by controlling the surface morphology of Si wafers. SEs were formed simultaneously, that is, in a single step for the doping process on different surface morphologies, nano/micro-surfaces, which were formed during the texturing processes; in the same doping process, the nano- and micro-structured areas showed different sheet resistances. In addition, the difference in sheet resistance between the heavily doped and shallow emitters could be controlled from almost 0 to 60 Ω/sq by changing the doping process conditions, pre-deposition and driving time, and temperature. Regarding cell fabrication, wafers simultaneously doped in the same tube were used. The sheet resistance of the homogeneously doped-on standard micro-pyramid surface was approximately 82 Ω/sq, and those of the selectively formed nano/micro-surfaces doped on were on 62 and 82 Ω/sq, respectively. As a result, regarding doped-on selectively formed nano/micro-surfaces, SE cells showed a JSC increase (0.44 mA/cm2) and a fill factor (FF) increase (0.6%) with respect to the homogeneously doped cells on the micro-pyramid surface, resulting in about 0.27% enhanced conversion efficiency.

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