Journal articles: 'Phoretic interactions'

1

Šimkus, Remigijus, Rita Meškienė, Agota Aučynaitė, Žilvinas Ledas, Romas Baronas, and Rolandas Meškys. "Phoretic interactions and oscillations in active suspensions of growing Escherichia coli." Royal Society Open Science 5, no. 5 (May 2018): 180008. http://dx.doi.org/10.1098/rsos.180008.

Full text

Abstract:

Bioluminescence imaging experiments were carried out to characterize spatio-temporal patterns of bacterial self-organization in active suspensions (cultures) of bioluminescent Escherichia coli and its mutants. An analysis of the effects of mutations shows that spatio-temporal patterns formed in standard microtitre plates are not related to the chemotaxis system of bacteria. In fact, these patterns are strongly dependent on the properties of mutants that characterize them as self-phoretic (non-flagellar) swimmers. In particular, the observed patterns are essentially dependent on the efficiency of proton translocation across membranes and the smoothness of the cell surface. These characteristics can be associated, respectively, with the surface activity and the phoretic mobility of a colloidal swimmer. An analysis of the experimental data together with mathematical modelling of pattern formation suggests the following: (1) pattern-forming processes can be described by Keller–Segel-type models of chemotaxis with logistic cell kinetics; (2) active cells can be seen as biochemical oscillators that exhibit phoretic drift and alignment; and (3) the spatio-temporal patterns in a suspension of growing E. coli form due to phoretic interactions between oscillating cells of high metabolic activity.

APA, Harvard, Vancouver, ISO, and other styles

2

Santos, Jean C., Everton Tizo-Pedroso, and Geraldo Wilson Fernandes. "A case of phoresy of Semeiochernes armiger Balzan, 1892 (Pseudoscorpiones: Chernetidae) on the giant tropical fly Pantophthalmus tabaninus Thunberg, 1819 (Diptera: Pantophthalmidae) in an Amazonian rain forest, Pará." Lundiana: International Journal of Biodiversity 6, sup. (November 4, 2005): 11–12. http://dx.doi.org/10.35699/2675-5327.2005.22110.

Full text

Abstract:

Pseudoscorpions have the ability to attach themselves to a wide variety of more mobile arthropods. This interaction has been termed phoresy. We report on a phoretic interaction of Semeiochernes armiger with a giant tropical fly Pantophthalmus tabaninus in an Amazonian rain forest. Two males and two females of S. armiger were found attached to the right posterior leg of the fly. In addition, more than two hundred mites were found on the thorax of the host fly. Long term and detailed studies on the phoretic associations of pseudoscorpions and hosts in the neotropical rain forest would contribute to a better understanding of these interactions. Keywords: Diptera, Phoresy, Pseudoscorpions, Porto Trombetas, Rain forest.

APA, Harvard, Vancouver, ISO, and other styles

3

BRADY, JOHN F. "Particle motion driven by solute gradients with application to autonomous motion: continuum and colloidal perspectives." Journal of Fluid Mechanics 667 (December 3, 2010): 216–59. http://dx.doi.org/10.1017/s0022112010004404.

Full text

Abstract:

Diffusiophoresis, the motion of a particle in response to an externally imposed concentration gradient of a solute species, is analysed from both the traditional coarse-grained macroscopic (i.e. continuum) perspective and from a fine-grained micromechanical level in which the particle and the solute are treated on the same footing as Brownian particles dispersed in a solvent. It is shown that although the two approaches agree when the solute is much smaller in size than the phoretic particle and is present at very dilute concentrations, the micromechanical colloidal perspective relaxes these restrictions and applies to any size ratio and any concentration of solute. The different descriptions also provide different mechanical analyses of phoretic motion. At the continuum level the macroscopic hydrodynamic stress and interactive force with the solute sum to give zero total force, a condition for phoretic motion. At the colloidal level, the particle's motion is shown to have two contributions: (i) a ‘back-flow’ contribution composed of the motion of the particle due to the solute chemical potential gradient force acting on it and a compensating fluid motion driven by the long-range hydrodynamic velocity disturbance caused by the chemical potential gradient force acting on all the solute particles and (ii) an indirect contribution arising from the mutual interparticle and Brownian forces on the solute and phoretic particle, that contribution being non-zero because the distribution of solute about the phoretic particle is driven out of equilibrium by the chemical potential gradient of the solute. At the colloidal level the forces acting on the phoretic particle – both the statistical or ‘thermodynamic’ chemical potential gradient and Brownian forces and the interparticle force – are balanced by the Stokes drag of the solvent to give the net phoretic velocity.For a particle undergoing self-phoresis or autonomous motion, as can result from chemical reactions occurring asymmetrically on a particle surface, e.g. catalytic nanomotors, there is no imposed chemical potential gradient and the back-flow contribution is absent. Only the indirect Brownian and interparticle forces contribution is responsible for the motion. The velocity of the particle resulting from this contribution can be written in terms of a mobility times the integral of the local ‘solute pressure’ – the solute concentration times the thermal energy – over the surface of contact between the particle and the solute. This was the approach taken by Córdova-Figueroa & Brady (Phys. Rev. Lett., vol. 100, 2008, 158303) in their analysis of self-propulsion. It is shown that full hydrodynamic interactions can be incorporated into their analysis by a simple scale factor.

APA, Harvard, Vancouver, ISO, and other styles

4

Liebchen, Benno, and Aritra K. Mukhopadhyay. "Interactions in active colloids." Journal of Physics: Condensed Matter 34, no. 8 (December 9, 2021): 083002. http://dx.doi.org/10.1088/1361-648x/ac3a86.

Full text

Abstract:

Abstract The past two decades have seen a remarkable progress in the development of synthetic colloidal agents which are capable of creating directed motion in an unbiased environment at the microscale. These self-propelling particles are often praised for their enormous potential to self-organize into dynamic nonequilibrium structures such as living clusters, synchronized super-rotor structures or self-propelling molecules featuring a complexity which is rarely found outside of the living world. However, the precise mechanisms underlying the formation and dynamics of many of these structures are still barely understood, which is likely to hinge on the gaps in our understanding of how active colloids interact. In particular, besides showing comparatively short-ranged interactions which are well known from passive colloids (Van der Waals, electrostatic etc), active colloids show novel hydrodynamic interactions as well as phoretic and substrate-mediated ‘osmotic’ cross-interactions which hinge on the action of the phoretic field gradients which are induced by the colloids on other colloids in the system. The present article discusses the complexity and the intriguing properties of these interactions which in general are long-ranged, non-instantaneous, non-pairwise and non-reciprocal and which may serve as key ingredients for the design of future nonequilibrium colloidal materials. Besides providing a brief overview on the state of the art of our understanding of these interactions a key aim of this review is to emphasize open key questions and corresponding open challenges.

APA, Harvard, Vancouver, ISO, and other styles

5

Pérez-Martínez, Sandra, and María Lourdes Moraza. "First Interaction Network of Sarcosaprophagous Fauna (Acari and Insecta) Associated with Animal Remains in a Mediterranean Region (Northern Spain)." Insects 13, no. 7 (July 6, 2022): 610. http://dx.doi.org/10.3390/insects13070610.

Full text

Abstract:

The potential of insects for forensic investigations has been known for more than 700 years. However, arthropods such as mites could also play a role in these investigations. The information obtained from insects, together with their phoretic mites, is of special interest in terms of estimating the time and geographical location of death. This paper presents the first interaction network between phoretic mites and their host insects in Navarra. It also reports the first time that an interaction network was applied to animal remains of forensic relevance. The data reveal the degrees of specificity of the interactions established, the biological and ecological characteristics of the mites at the time of association, and factors that played important roles in the mites’ dispersion. Fauna was collected using 657 traps baited with 20 g of pig carrion over a year. Only 0.6% of insects collected carried phoretic mites. The network comprised 312 insects (275 beetles, 37 flies) and 1533 mites and was analyzed using various packages of the R programming language. We contribute new host insect records for 15 mites, 3 new records of insects as hosts, 5 new mite records for the Iberian Peninsula, and 2 new mites records and 8 new insect records for Navarra.

APA, Harvard, Vancouver, ISO, and other styles

6

Khadem-Safdarkhani, Hamid, Hamidreza Hajiqanbar, Markus Riegler, Owen Seeman, and Alihan Katlav. "Two New Phoretic Species of Heterostigmatic Mites (Acari: Prostigmata: Neopygmephoridae and Scutacaridae) on Australian Hydrophilid Beetles (Coleoptera: Hydrophilidae)." Insects 13, no. 5 (May 22, 2022): 483. http://dx.doi.org/10.3390/insects13050483.

Full text

Abstract:

Many heterostigmatic mites (Acari: Prostigmata: Heterostigmata) display a wide range of symbiotic interactions, from phoresy to parasitism, with a variety of insects. Australia is expected to harbour a rich diversity of heterostigmatic mites; however, its phoretic fauna and its host associations remain mainly unexplored. We conducted a short exploration of Australian insect-associated phoretic mites in summer 2020 and found two new phoretic heterostigmatic species on a semiaquatic hydrophilid beetle species, Coelostoma fabricii (Montrouzier, 1860) (Coleoptera: Hydrophilidae). Here, we describe these two new species, Allopygmephorus coelostomus sp. nov. (Neopygmephoridae) and Archidispus hydrophilus sp. nov. (Scutacaridae), which both belong to the superfamily Pygmephoroidea. Both species are distinct from their congeners, with a plesiomorphic character, bearing a median genital sclerite (mgs). Our study reports both genera for the first time from Australia.

APA, Harvard, Vancouver, ISO, and other styles

7

Kanso, Eva, and Sébastien Michelin. "Phoretic and hydrodynamic interactions of weakly confined autophoretic particles." Journal of Chemical Physics 150, no. 4 (January 28, 2019): 044902. http://dx.doi.org/10.1063/1.5065656.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Michelin, Sébastien, and Eric Lauga. "Phoretic self-propulsion at finite Péclet numbers." Journal of Fluid Mechanics 747 (April 23, 2014): 572–604. http://dx.doi.org/10.1017/jfm.2014.158.

Full text

Abstract:

AbstractPhoretic self-propulsion is a unique example of force- and torque-free motion on small scales. The classical framework describing the flow field around a particle swimming by self-diffusiophoresis neglects the advection of the solute field by the flow and assumes that the chemical interaction layer is thin compared to the particle size. In this paper we quantify and characterize the effect of solute advection on the phoretic swimming of a sphere. We first rigorously derive the regime of validity of the thin-interaction-layer assumption at finite values of the Péclet number (${Pe}$). Under this assumption, we solve computationally the flow around Janus phoretic particles and examine the impact of solute advection on propulsion and the flow created by the particle. We demonstrate that although advection always leads to a decrease of the swimming speed and flow stresslet at high values of the Péclet number, an increase can be obtained at intermediate values of ${Pe}$. This possible enhancement of swimming depends critically on the nature of the chemical interactions between the solute and the surface. We then derive an asymptotic analysis of the problem at small ${Pe}$ which allows us to rationalize our computational results. Our computational and theoretical analysis is accompanied by a parallel study of the influence of reactive effects at the surface of the particle (Damköhler number) on swimming.

APA, Harvard, Vancouver, ISO, and other styles

9

Al-Deeb, Mohammad Ali, Sabir Bin Muzaffar, and Eyas Mohammad Sharif. "Interactions between Phoretic Mites and the Arabian Rhinoceros Beetle,Oryctesagamemnon arabicus." Journal of Insect Science 12, no. 128 (November 2012): 1–14. http://dx.doi.org/10.1673/031.012.12801.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Choudhary, A., T. Renganathan, and S. Pushpavanam. "Inertial migration of an electrophoretic rigid sphere in a two-dimensional Poiseuille flow." Journal of Fluid Mechanics 874 (July 12, 2019): 856–90. http://dx.doi.org/10.1017/jfm.2019.479.

Full text

Abstract:

There has been a recent interest in integrating external fields with inertial microfluidic devices to tune particle focusing. In this work, we analyse the inertial migration of an electrophoretic particle in a two-dimensional Poiseuille flow with an electric field applied parallel to the walls. For a thin electrical double layer, the particle exhibits a slip-driven electrokinetic motion along the direction of the applied electric field, which causes the particle to lead or lag the flow (depending on its surface charge). The fluid disturbance caused by this slip-driven motion is characterized by a rapidly decaying source-dipole field which alters the inertial lift on the particle. We determine this inertial lift using the reciprocal theorem. Assuming no wall effects, we derive an analytical expression for a ‘phoretic lift’ which captures the modification to the inertial lift due to electrophoresis. We also take wall effects into account, at the leading order, using the method of reflections. We find that for a leading particle, the phoretic lift acts towards the regions of high shear (i.e. walls), while the reverse is true for a lagging particle. Using an order-of-magnitude analysis, we obtain different components of the inertial force and classify them on the basis of the interactions from which they emerge. We show that the dominant contribution to the phoretic lift originates from the interaction of the source-dipole field (generated by the electrokinetic slip at the particle surface) with the stresslet field (generated due to particle’s resistance to strain in the background flow). Furthermore, to contrast the slip-driven phenomenon (electrophoresis) from the force-driven phenomenon (buoyancy) in terms of their influence on the inertial migration, we also study a non-neutrally buoyant particle. We show that the gravitational effects alter the inertial lift primarily through the interaction of the background shear with the buoyancy-induced Stokeslet field.

APA, Harvard, Vancouver, ISO, and other styles

11

Scagliarini, Andrea, and Ignacio Pagonabarraga. "Unravelling the role of phoretic and hydrodynamic interactions in active colloidal suspensions." Soft Matter 16, no. 38 (2020): 8893–903. http://dx.doi.org/10.1039/c8sm01831f.

Full text

Abstract:

We study numerically suspensions of self-diffusiophoretic colloids for various colloid–solute affinities. We show that hydrodynamics affects the aggregation kinetics and the cluster morphology, significantly hindering cluster growth.

APA, Harvard, Vancouver, ISO, and other styles

12

Hodgkin, Lisa K., Mark A. Elgar, and Matthew R. E. Symonds. "Positive and negative effects of phoretic mites on the reproductive output of an invasive bark beetle." Australian Journal of Zoology 58, no. 3 (2010): 198. http://dx.doi.org/10.1071/zo10034.

Full text

Abstract:

When multiple species coexist upon a single host, their combined effect on the host can be unpredictable. We explored the effect of phoretic mites on the reproductive output of the five-spined bark beetle, Ips grandicollis. Using correlative approaches and experimental manipulation of mite numbers we examined how mite load affected the number, size and condition of bark beetle offspring produced. We found that mites have both negative and positive consequences on different aspects of bark beetle reproduction. Females from which mites were removed were more fecund and produced larger offspring than females with mites, implying a cost of mite loads. However, when mites were present on females, those bearing the highest mite loads produced offspring that were larger and in better condition, indicating a beneficial effect of mites. These data suggest that phoretic interactions between mites and bark beetles differ over the course of the host’s lifespan, with either the mites interacting in different ways with different life stages of the host (parasitic on adult, mutualistic with larvae), and/or the beetles being host to different mite assemblages over their lifetime.

APA, Harvard, Vancouver, ISO, and other styles

13

Che, Shengping, Jianhua Zhang, Fangzhi Mou, Xia Guo, Joshua E. Kauffman, Ayusman Sen, and Jianguo Guan. "Light-Programmable Assemblies of Isotropic Micromotors." Research 2022 (July 7, 2022): 1–12. http://dx.doi.org/10.34133/2022/9816562.

Full text

Abstract:

“Life-like” nonequilibrium assemblies are of increasing significance, but suffering from limited steerability as they are generally based on micro/nanomotors with inherent asymmetry in chemical composition or geometry, of which the vigorous random Brownian rotations disturb the local interactions. Here, we demonstrate that isotropic photocatalytic micromotors, due to the persistent phoretic flow from the illuminated to shadowed side irrespective of their Brownian rotations, experience light-programmable local interactions (reversibly from attraction to repulsion and/or alignment) depending on the direction of the incident lights. Thus, they can be organized into a variety of tunable nonequilibrium assemblies, such as apolar solids (i.e., immobile colloidal crystal), polar liquids (i.e., phototactic colloidal stream), and polar solids (i.e., phototactic colloidal crystal), which can further be “cut” into a predesigned pattern by utilizing the switching motor-motor interactions at superimposed-light edges. This work facilitates the development of active matters and motile functional microdevices.

APA, Harvard, Vancouver, ISO, and other styles

14

Gutierrez, Daniel H., John Lake, Cristina Javier, Arthur Cheng, Zuki Tanaka, Nicolas J. Londoño, and Bin Chen. "Phoretic Deposition of Graphene on Manganese-Cobalt Oxide Composites for Supercapacitor Electrodes." Advances in Science and Technology 77 (September 2012): 302–6. http://dx.doi.org/10.4028/www.scientific.net/ast.77.302.

Full text

Abstract:

Great focus has been directed towards double-layer capacitance and Faradic, redox reactions because of their long device lifetimes and their high power densities, respectively. Our novel approach to combining these mechanisms in a tri-layered composite electrode promises to increase the energy densities of the device, without sacrificing the supercapacitance and the high power densities attributed with it. Initial analysis of the interfacial interactions of graphene oxide (GO) and manganese oxide (MnO2) were promising. This paper aims to further demonstrate the tri-layered composite by forming a layer of reduced graphene oxide (rGO) on MnO2 nanowires and cobalt oxide nanorods. We have successfully created the first of a kind supercapacitor electrode material as a scalable device. In this paper, in addition to analysis of the composite electrode, we present modifications to the traditional electrophoretic deposition process and optimizations to the thermal reduction of GO in order to create rGO surfaces on substrates that are normally difficult to adhere it to.

APA, Harvard, Vancouver, ISO, and other styles

15

Lombardero, Maria J., Kier D. Klepzig, John C. Moser, and Matthew P. Ayres. "Biology, demography and community interactions of Tarsonemus (Acarina: Tarsonemidae) mites phoretic on Dendroctonus frontalis (Coleoptera: Scolytidae)." Agricultural and Forest Entomology 2, no. 3 (August 2000): 193–202. http://dx.doi.org/10.1046/j.1461-9563.2000.00070.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Zheng, Jing, Jingyuan Chen, Yakang Jin, Yan Wen, Yijiang Mu, Changjin Wu, Yufeng Wang, et al. "Photochromism from wavelength-selective colloidal phase segregation." Nature 617, no. 7961 (May 17, 2023): 499–506. http://dx.doi.org/10.1038/s41586-023-05873-4.

Full text

Abstract:

AbstractPhase segregation is ubiquitously observed in immiscible mixtures, such as oil and water, in which the mixing entropy is overcome by the segregation enthalpy1–3. In monodispersed colloidal systems, however, the colloidal–colloidal interactions are usually non-specific and short-ranged, which leads to negligible segregation enthalpy4. The recently developed photoactive colloidal particles show long-range phoretic interactions, which can be readily tuned with incident light, suggesting an ideal model for studying phase behaviour and structure evolution kinetics5,6. In this work, we design a simple spectral selective active colloidal system, in which TiO2 colloidal species were coded with spectral distinctive dyes to form a photochromic colloidal swarm. In this system, the particle–particle interactions can be programmed by combining incident light with various wavelengths and intensities to enable controllable colloidal gelation and segregation. Furthermore, by mixing the cyan, magenta and yellow colloids, a dynamic photochromic colloidal swarm is formulated. On illumination of coloured light, the colloidal swarm adapts the appearance of incident light due to layered phase segregation, presenting a facile approach towards coloured electronic paper and self-powered optical camouflage.

APA, Harvard, Vancouver, ISO, and other styles

17

Yabunaka, Shunsuke, and Natsuhiko Yoshinaga. "Collision between chemically driven self-propelled drops." Journal of Fluid Mechanics 806 (September 30, 2016): 205–33. http://dx.doi.org/10.1017/jfm.2016.602.

Full text

Abstract:

We use analytical and numerical approaches to investigate head-on collisions between two self-propelled drops described as a phase separated binary mixture. Each drop is driven by chemical reactions that isotropically produce or consume the concentration of a third chemical component, which affects the surface tension of the drop. The isotropic distribution of the concentration field is destabilized by motion of the drop, which is created by the Marangoni flow from the concentration-dependent surface tension. This symmetry-breaking self-propulsion is distinct from other self-propulsion mechanisms due to its intrinsic polarity of squirmers and self-phoretic motion; there is a bifurcation point below which the drop is stationary and above which it moves spontaneously. When two drops are moving in the opposite direction along the same axis, their interactions arise from hydrodynamics and concentration overlap. We found that two drops exhibit either an elastic collision or fusion, depending on the distance from their bifurcation point, which may be controlled, for example, by viscosity. An elastic collision occurs when there is a balance between dissipation and the injection of energy by chemical reactions. We derive the reduced equations for the collision between two drops and analyse the contributions from the two interactions. The concentration-mediated interaction is found to dominate the hydrodynamic interaction for a head-on collision.

APA, Harvard, Vancouver, ISO, and other styles

18

Rahiminejad, Vahid, Hamidreza Hajiqanbar, and Ali Asghar Talebi. "An alpha diversity survey of Heterostigmatic mites (Trombidiformes, Prostigmata) phoretic on scarabaeoid beetles in Hyrcani forest, northern Iran." Systematic and Applied Acarology 25, no. 11 (October 23, 2020): 2033–46. http://dx.doi.org/10.11158/saa.25.11.9.

Full text

Abstract:

Complicated ecological interactions among numerous species could drive ecosystems towards more stability. Scarabaeoid beetles render a profound contribution to ecological processes through establishing symbiotic relationships with a variety of fungivorous mites. Such interactions with mites play important roles in forest conservation and biodiversity. In this study, we aimed to peruse the scarabaeoid-mite associations by alpha diversity tools. We investigated species diversity, richness and host range of heterostigmatic mites (Trombidiformes: Prostigmata) associated with scarabaeoid beetles. A total of 1113 individual mites belonging to 20 species were recorded from 870 adult individuals of Scarabaeidae (six species), 540 Lucanidae (two species) and 360 Geotrupidae (one species). Attachment site of the mites on the hosts were examined and discussed; that indicated they have most and least safety status on Lucanidae and Scarabaeidae, respectively. Spatulaphorus gorganica (Pygmephoridae) was the most frequent mite species, and Premicrodispus spinosus, P. brevisetus and Paramicrodispus scarabidophilus (Microdispidae) relatively common, whereas the other mites occurred occasionally. The host family Scarabaeidae showed to be more diverse than two other families, associated with highest number of mite species. The results of phoresy and host-range of heterostigmatic mites have been discussed.

APA, Harvard, Vancouver, ISO, and other styles

19

Wu, Pengxiang, Yang Ge, Jia He, Muhammad Haseeb, and Runzhi Zhang. "Positive Interactions between Aceria pallida and Bactericera gobica on Goji Berry Plants." Insects 13, no. 7 (June 24, 2022): 577. http://dx.doi.org/10.3390/insects13070577.

Full text

Abstract:

The gall mite Aceria pallida and the psyllid Bactericera gobica are serious Goji berry pests. The mite can be phoretic on the psyllid to overwinter, but it is unclear whether the vector can obtain benefits from the phoront during the growing season. After detachment, the mite shares the same habitat with its vector, so there are very likely to be interspecific interactions. To better understand whether the interactions are positive or negative, information on relationships between abundances of A. pallida and B. gobica on leaves is needed. Here, B. gobica abundance was represented by the egg abundance because the inactive nymphs develop on the same sites after hatching. (1) We found a positive linear relationship between the gall diameter and the mite abundance in the gall (one more millimeter on gall diameter for every 30 mites increase), which provided a way to rapidly estimate mite abundances in the field by measuring gall diameters. (2) There was a positive relationship between the abundance of mites and psyllid eggs on leaves. (3) Both species had positive effects on each other’s habitat selections. More importantly, the interactions of the two species prevented leaf abscission induced by B. gobica (leaf lifespan increased by 62.9%), increasing the continuation of the psyllid population. Our study suggests positive interactions between two pests during the growing season. The positive relationship between A. pallida and B. gobica egg abundances highlights the increasing need for novel methods for Goji berry pest management. In practice, A. pallida control can be efficient by eliminating its vector B. gobica. Both pests can be controlled together, which reduces chemical usage.

APA, Harvard, Vancouver, ISO, and other styles

20

Schäffer, Sylvia, and Stephan Koblmüller. "Unexpected diversity in the host-generalist oribatid mite Paraleius leontonychus (Oribatida, Scheloribatidae) phoretic on Palearctic bark beetles." PeerJ 8 (September 11, 2020): e9710. http://dx.doi.org/10.7717/peerj.9710.

Full text

Abstract:

Bark beetles are feared as pests in forestry but they also support a large number of other taxa that exploit the beetles and their galleries. Among arthropods, mites are the largest taxon associated with bark beetles. Many of these mites are phoretic and often involved in complex interactions with the beetles and other organisms. Within the oribatid mite family Scheloribatidae, only two of the three nominal species of Paraleius have been frequently found in galleries of bark beetles and on the beetles themselves. One of the species, P. leontonychus, has a wide distribution range spanning over three ecozones of the world and is believed to be a host generalist, reported from numerous bark beetle and tree species. In the present study, phylogenetic analyses of one mitochondrial and two nuclear genes identified six well supported, fairly divergent clades within P. leontonychus which we consider to represent distinct species based on molecular species delimitation methods and largely congruent clustering in mitochondrial and nuclear gene trees. These species do not tend to be strictly host specific and might occur syntopically. Moreover, mito-nuclear discordance indicates a case of past hybridization/introgression among distinct Paraleius species, the first case of interspecific hybridization reported in mites other than ticks.

APA, Harvard, Vancouver, ISO, and other styles

21

Ewers, Robert M., Scott Bartlam, and Raphael K. Didham. "Altered species interactions at forest edges: contrasting edge effects on bumble bees and their phoretic mite loads in temperate forest remnants." Insect Conservation and Diversity 6, no. 5 (January 2, 2013): 598–606. http://dx.doi.org/10.1111/icad.12014.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Mori, Boyd A., Heather C. Proctor, David E. Walter, and Maya L. Evenden. "Phoretic mite associates of mountain pine beetle at the leading edge of an infestation in northwestern Alberta, Canada." Canadian Entomologist 143, no. 1 (February 2011): 44–55. http://dx.doi.org/10.4039/n10-043.

Full text

Abstract:

AbstractWe identified species of mites phoretically associated with mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), collected from bolts of lodgepole pine, Pinus contorta Douglas ex Louden (Pinaceae), and pheromone-baited traps in northwestern Alberta, Canada. Mite load and species composition were compared between beetle sexes and with beetle emergence time and estimated body size. The vast majority of mites associated with D. ponderosae in Alberta belonged to three species: Proctolaelaps subcorticalis Lindquist (Acari: Mesostigmata: Melicharidae), Histiogaster arborsignis Woodring (Acari: Astigmatina: Acaridae), and Tarsonemus ips Lindquist (Acari: Prostigmata: Tarsonemidae). There was no difference in mite loads on male and female beetles recovered from bolts in the laboratory and those from pheromone-baited traps in the field. More mites were found on larger beetles in the laboratory, but only T. ips showed this pattern on field-trapped beetles. There was no relationship between total mite load or load by mite species and beetle emergence time in the laboratory, but total mite load on field-trapped beetles decreased over the collecting season (10 June – 3 September 2009) at five collection locations (Grovedale, Blueberry Mountain, Hythe, Evergreen Park, and Glenleslie). This study is the first to document the assemblage of phoretic mites on D. ponderosae in Alberta and will help to direct future research on their interactions.

APA, Harvard, Vancouver, ISO, and other styles

23

Mercado, Javier, Beatriz Ortiz-Santana, and Shannon Kay. "Fungal Frequency and Mite Load Trends Interact with a Declining Mountain Pine Beetle Population." Forests 9, no. 8 (August 9, 2018): 484. http://dx.doi.org/10.3390/f9080484.

Full text

Abstract:

The mite and fungal biota associated with the mountain pine beetle (MPB) (Dendroctonus ponderosae Hopk.) may not be stable throughout an irruptive event. In congeneric beetles, variations in the frequency of their associated organisms affect population trends and similar effects may occur in MPB. We studied fungi and mite trends in a declining irruptive MPB population as it attacked three different pine hosts in the Colorado Front Range. During the study, we found two new associates including one biologically relevant mite and one beneficial blue-stain fungus. Fungi hyperphoretic on mites were also documented. This included beneficial and potentially detrimental species to the MPB. The frequency of several organisms varied between some years or pine hosts but not within male or female beetles. A large increase of Trichouropoda sp. and T. ips mites trended inversely with the declining beetle population, while a decrease in the beneficial blue-stain fungi trended similarly to the declining beetle population. We discuss the interactions and potential effects of phoretic biota in relation to (1) the MPB associates’ population trends, (2) the MPB incursions into cooler areas, and (3) the redundancy of blue-stain fungi carried by the MPB holobiont. These findings increase our knowledge of the mechanisms that influence MPB populations.

APA, Harvard, Vancouver, ISO, and other styles

24

Vissa, Sneha, Javier E. Mercado, Danielle Malesky, Derek A. Uhey, Boyd A. Mori, Wayne Knee, Maya L. Evenden, and Richard W. Hofstetter. "Patterns of Diversity in the Symbiotic Mite Assemblage of the Mountain Pine Beetle, Dendroctonus Ponderosae Hopkins." Forests 11, no. 10 (October 17, 2020): 1102. http://dx.doi.org/10.3390/f11101102.

Full text

Abstract:

The mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Scolytinae), is an economically important bark beetle species with a wide geographic range spanning from the southwestern United States into northern Canada. This beetle causes extensive tree mortality to 13 pine species. Mites (Acari) are common and abundant symbionts of mountain beetles that may influence their fitness through positive and negative interactions. We present a unique assessment of the mite associates of mountain pine beetles using measures of alpha and beta diversity. We sampled phoretic mites from five beetle populations: Arizona, Colorado, South Dakota, Utah (USA), and Alberta (Canada) that varied in host tree species, local climate, and beetle population level. We collected 4848 mites from 8 genera and 12 species. Fifty to seventy percent of beetles carried mites in flight with the highest mite loads occurring in middle and southern populations; decreasing in northern populations. Mite assemblages (i.e., both richness and composition) varied along a south to north latitudinal gradient and were driven by species turnover (i.e., species replacement). Differences in mite composition increased with distance between populations. We discuss climatic variation, environmental filtering, and host tree differences as factors that could affect differences in mite composition between beetle populations and discuss implications for functional shifts. Our results could represent a model for estimating diversity patterns of mite symbionts associated with other major insect pests in coniferous forest systems.

APA, Harvard, Vancouver, ISO, and other styles

25

Yu, Lingxia, Manyi Yang, Jianguo Guan, and Fangzhi Mou. "Ultrasmall Fe2O3 Tubular Nanomotors: The First Example of Swarming Photocatalytic Nanomotors Operating in High-Electrolyte Media." Nanomaterials 13, no. 8 (April 14, 2023): 1370. http://dx.doi.org/10.3390/nano13081370.

Full text

Abstract:

Self-propelled chemical micro/nanomotors (MNMs) have demonstrated considerable potential in targeted drug delivery, (bio)sensing, and environmental remediation due to their autonomous nature and possible intelligent self-targeting behaviors (e.g., chemotaxis and phototaxis). However, these MNMs are commonly limited by their primary propulsion mechanisms of self-electrophoresis and electrolyte self-diffusiophoresis, making them prone to quenching in high electrolyte environments. Thus, the swarming behaviors of chemical MNMs in high-electrolyte media remain underexplored, despite their potential to enable the execution of complex tasks in high-electrolyte biological media or natural waters. In this study, we develop ultrasmall tubular nanomotors that exhibit ion-tolerant propulsions and collective behaviors. Upon vertical upward UV irradiation, the ultrasmall Fe2O3 tubular nanomotors (Fe2O3 TNMs) demonstrate positive superdiffusive photogravitaxis and can further self-organize into nanoclusters near the substrate in a reversible manner. After self-organization, the Fe2O3 TNMs exhibit a pronounced emergent behavior, allowing them to switch from random superdiffusions to ballistic motions near the substrate. Even at a high electrolyte concentration (Ce), the ultrasmall Fe2O3 TNMs retain a relatively thick electrical double layer (EDL) compared to their size, and the electroosmotic slip flow in their EDL is strong enough to propel them and induce phoretic interactions among them. As a result, the nanomotors can rapidly concentrate near the substrate and then gather into motile nanoclusters in high-electrolyte environments. This work opens a gate for designing swarming ion-tolerant chemical nanomotors and may expedite their applications in biomedicine and environmental remediation.

APA, Harvard, Vancouver, ISO, and other styles

26

Ibrahim, Yahaya, and Saratu Abddulfatah. "PAIR INTERACTION OF ACTIVE COLLOIDS IN AN EXTERNAL CHEMICAL GRADIENT." FUDMA JOURNAL OF SCIENCES 6, no. 3 (July 6, 2022): 271–77. http://dx.doi.org/10.33003/fjs-2022-0603-999.

Full text

Abstract:

We study the pair interaction of chemically isotropic active colloidal particles in an externally imposed chemical gradient. Colloid particles migrate in response to a gradient of chemical solutes (i.e., via the diffusiophoresis mechanism). The particles motion induces fluid flow and distort locally the background chemical concentration field. Using the methods of images, we calculate the phoretic inter-particle interaction between two symmetric active colloids in the presence of an externally applied gradient. We highlight an interesting colloidal dipole that would arise from tuning the surface and chemical activity of the colloids. The colloidal phoretic dipoles share similar properties to the electrostatic dipoles. The inter-particle interaction we obtained is an important component for a large-scale simulation of the active colloid suspension. It may also help towards better understanding of the active systems’ emergent phenomena

APA, Harvard, Vancouver, ISO, and other styles

27

Wei, Jiachen, Simón Ramírez-Hinestrosa, Jure Dobnikar, and Daan Frenkel. "Effect of the interaction strength and anisotropy on the diffusio-phoresis of spherical colloids." Soft Matter 16, no. 15 (2020): 3621–27. http://dx.doi.org/10.1039/c9sm02053e.

Full text

Abstract:

We study gradient-driven diffusio-phoretic flow around a fixed colloid. The flow enabled by the colloid-solute attraction depends sensitively on the interaction strength and anisotropy. The strength dependence is non-monotonic due to trapping of the solute particles around the colloid.

APA, Harvard, Vancouver, ISO, and other styles

28

Lemaitre, Pascal, Mamadou Sow, Arnaud Quérel, Alexis Dépée, Marie Monier, Thibaut Menard, and Andrea Flossmann. "Contribution of Phoretic and Electrostatic Effects to the Collection Efficiency of Submicron Aerosol Particles by Raindrops." Atmosphere 11, no. 10 (September 24, 2020): 1028. http://dx.doi.org/10.3390/atmos11101028.

Full text

Abstract:

This article presents an experimental study, performed in the BERGAME setup, dedicated to studying the collection of submicron aerosol particles by raindrops. The initial aim was to focus on the influence of the electrical charges of raindrops on the efficiency with which they collect aerosol particles. However, in the relative humidity range considered in this article (26–36%), measurements highlight a first-order role of phoretic effect for submicron aerosol particles. Indeed, measurements highlight a 100% increase in the collection efficiency for each percentage decrease in the atmospheric relative humidity. Phoretic effects are known to play a role in collection by drops; however, none of the models found in the literature predicts the same magnitude as the one presently measured. Characterization of the aerosol trajectories around the drop, accelerated to terminal velocity, seems to show a coupling between phoretic effects and rear capture. This interaction, already suggested by Grover et al., is a line of explanation for such a sharp unpredicted increase of the collection efficiency with moisture decrease.

APA, Harvard, Vancouver, ISO, and other styles

29

Karunakaran, Harikaran, and Selvamuthukumaran Thirunavukkarasu. "Progression of parasitism from phoresy in mites." International Journal of Zoology and Applied Biosciences 8, no. 4 (August 31, 2023): 35–40. http://dx.doi.org/10.55126/ijzab.2023.v08.i04.006.

Full text

Abstract:

The mites are the smallest (less than a millimeter in length), the most diverse, and the most common of all arachnids. Mites are ubiquitous and inhabit all known terrestrial, marine, and freshwater habitats, including arctic and alpine extremes, tropical plains and desert barrens, and surface and mineral soils (Dunlop and Alberti, 2008). More than 55,000 species have been described up to date, accounting for 5% of all living species today. Mites are experts at transport with the aid of large animals, mostly insects. It is a temporary relationship called phoresy that allows the mites to exploit scarce resources. Phoresy in the subclass Acari includes insects that feed on carriers. Phoresy evolved from free-living ancestors. The primary waste material used by floating mites appears to be rotting logs. However, rapid changes in the later life stage allowed the development of short-term resources. Although phoresy is a form of social interaction, most interact with mites. These relationships can be very complex and context-specific, but they often use the vector's sources or descendants (Seeman and Walter, 2023). The switch from phoretic to parasitism seems popular, but the scientific evidence for a switch from phoretic to permanent parasitism seems to be lacking.

APA, Harvard, Vancouver, ISO, and other styles

30

Lubich, Chiara C. F., André R. Martins, Carlos E. C. Freitas, Lawrence E. Hurd, and Flávia K. Siqueira-Souza. "A candiru, Paracanthopoma sp. (Siluriformes: Trichomycteridae), associated with a thorny catfish, Doras phlyzakion (Siluriformes: Doradidae), in a tributary of the middle Rio Negro, Brazilian Amazon." Acta Ichthyologica et Piscatoria 51, no. 3 (September 9, 2021): 241–44. http://dx.doi.org/10.3897/aiep.51.e64324.

Full text

Abstract:

Amazonian vampire catfish, known regionally as “candiru”, are recognized as hematophagous fishes, but information on their ecology remains limited. We provide the first report of Paracanthopoma sp. (Vandelliinae) found attached to the body surface of a thorny catfish, Doras phlyzakion Sabaj Pérez et Birindelli, 2008, bellow the lateral bony plates, rather than at the gills where they have usually been found. The specimens had not recently ingested blood or other identifiable fish remains (flesh, skin, or mucus), which could be an indication they have been using this host for protection or as a phoretic association, rather than for feeding. Thus, the interaction of vampire fish with the host catfish may be more complex than previously understood.

APA, Harvard, Vancouver, ISO, and other styles

31

Lubich, Chiara C. F., André R. Martins, Carlos E. C. Freitas, Lawrence E. Hurd, and Flávia K. Siqueira-Souza. "A candiru, Paracanthopoma sp. (Siluriformes: Trichomycteridae), associated with a thorny catfish, Doras phlyzakion (Siluriformes: Doradidae), in a tributary of the middle Rio Negro, Brazilian Amazon." Acta Ichthyologica et Piscatoria 51, no. 3 (September 9, 2021): 241–44. http://dx.doi.org/10.3897/aiep.51.64324.

Full text

Abstract:

Amazonian vampire catfish, known regionally as “candiru”, are recognized as hematophagous fishes, but information on their ecology remains limited. We provide the first report of Paracanthopoma sp. (Vandelliinae) found attached to the body surface of a thorny catfish, Doras phlyzakion Sabaj Pérez et Birindelli, 2008, bellow the lateral bony plates, rather than at the gills where they have usually been found. The specimens had not recently ingested blood or other identifiable fish remains (flesh, skin, or mucus), which could be an indication they have been using this host for protection or as a phoretic association, rather than for feeding. Thus, the interaction of vampire fish with the host catfish may be more complex than previously understood.

APA, Harvard, Vancouver, ISO, and other styles

32

Mamed-zade, A. M. "Effect of electro-kinetic processes on filtration of fluids and gas in porous medium." Azerbaijan Oil Industry, no. 2 (February 15, 2021): 16–21. http://dx.doi.org/10.37474/0365-8554/2021-2-16-21.

Full text

Abstract:

The paper reviews the fluid and gas flow in the porous medium considering electro-kinetic phenomena – electro-phoresis and electro-osmosis, as well as the charges associated with them. These phenomena are due to the double electric layer on the border of division of disperse system phases. Electro-kinetic phenomena are follows: electro-phoresis, electro-osmosis, flow potential (Quincke effect) and sedimentation potential (Dorn effect). The formulas for the motion of fluid and gas in porous medium considering the properties of porous medium and saturating them fluids, as well as the interaction between them, which is described with electro-kinematic phenomena, have been obtained. Obtained formulas have been evaluated via the results of laboratory researches.

APA, Harvard, Vancouver, ISO, and other styles

33

Wei, Jiachen. "The Dependence of Diffusio-Phoretic Mobility and Aggregation Properties of Proteins on Intermolecular Interaction in Confined System." Molecular & Cellular Biomechanics 16, S2 (2019): 103–4. http://dx.doi.org/10.32604/mcb.2019.07721.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Domínguez, Lillian G., Juan J. Lezcano, Indra Rodríguez, Roberto J. Miranda, and Sergio C. Bermúdez. "Is Geckobiella stamii (Acari: Pterygosomatidae) a hyperparasite or phoretic on Amblyomma dissimile (Acari: Ixodidae) associated with Iguana iguana from Panama?" Acarologia 60, no. 1 (January 17, 2020): 40–44. http://dx.doi.org/10.24349/acarologia/20204356.

Full text

Abstract:

In this work, we present the first report of an interaction between Geckobiella stamii and Amblyomma dissimile removed from green iguanas (Iguana iguana) of Panama. From 3045 A. dissimile examined, one larva, two females and one male had mites adhered to the body and 23 female and 3 male ticks had mite eggs on the ventral surface of the idiosoma. The eggs were covered with white finger-like covers. The possible nature of the interaction between G. stamii and A. dissimile is discussed.

APA, Harvard, Vancouver, ISO, and other styles

35

Badets, Mathieu, and Louis Du Preez. "Phoretic interaction between the kangaroo leech Marsupiobdella africana (Hirudinea: Glossiphoniidae) and the cape river crab Potamonautes perlatus (Decapoda: Potamonautidae)." International Journal for Parasitology: Parasites and Wildlife 3, no. 1 (April 2014): 6–11. http://dx.doi.org/10.1016/j.ijppaw.2013.10.001.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Jakubowska, Agata K., Rosa Murillo, Arkaitz Carballo, Trevor Williams, Jan W. M. van Lent, Primitivo Caballero, and Salvador Herrero. "Iflavirus increases its infectivity and physical stability in association with baculovirus." PeerJ 4 (March 3, 2016): e1687. http://dx.doi.org/10.7717/peerj.1687.

Full text

Abstract:

Virus transmission and the prevalence of infection depend on multiple factors, including the interaction with other viral pathogens infecting the same host. In this study, active replication of an iflavirus,Spodoptera exigua iflavirus 1(orderPicornavirales) was observed in the offspring of insects that survived following inoculation with a pathogenic baculovirus,Spodoptera exiguamultiple nucleopolyhedrovirus. Tracking the origin of the iflavirus suggested the association of this virus with the occlusion bodies of the baculovirus. Here we investigated the effect of this association on the stability and infectivity of both viruses. A reduction in baculovirus pathogenicity, without affecting its infectivity and productivity, was observed when associated with the iflavirus. In contrast, viral association increased the infectivity of the iflavirus and its resistance to ultraviolet radiation and high temperature, two of the main factors affecting virus stability in the field. In addition, electron microscopy analysis revealed the presence of particles resembling iflavirus virions inside the occlusion bodies of the baculovirus, suggesting the possible co-occlusion of both viruses. Results reported here are indicative of facultative phoresis of a virus and suggest that virus–virus interactions may be more common than currently recognized, and may be influential in the ecology of baculovirus and host populations and in consequence in the use of baculoviruses as biological insecticides.

APA, Harvard, Vancouver, ISO, and other styles

37

Sharifi-Mood, Nima, Ali Mozaffari, and Ubaldo M. Córdova-Figueroa. "Pair interaction of catalytically active colloids: from assembly to escape." Journal of Fluid Mechanics 798 (June 16, 2016): 910–54. http://dx.doi.org/10.1017/jfm.2016.317.

Full text

Abstract:

The dynamics and pair trajectories of two self-propelled (active) colloids in a quiescent fluid for both axisymmetric and asymmetric cases are reported. The autonomous motions of the colloids are due to a catalytic chemical reaction taking place asymmetrically on their surfaces that generates a concentration gradient of interactive solutes around the particles and actuates particle propulsion. A combined analytical–numerical technique was developed to solve the coupled mass conservation equation for the solute and the hydrodynamics between the colloids in the Stokes flow regime. For axisymmetric motions, the translational swimming velocities of the particles in the near field can be enhanced or weakened (compared to their motions when they are far apart) depending on the relative orientations of their active sections. Moreover, it can be shown that different surface activities of two symmetric particles, e.g. an inert versus a catalytic particle or two catalytic particles, can also lead to a propulsion where the far-field swimming velocity for the inert and the catalytic particle attenuate as ${\sim}1/{\it\Delta}^{2}$ and ${\sim}1/{\it\Delta}^{5}$ respectively, ${\it\Delta}$ is the non-dimensional centre-to-centre distance. For asymmetric motions, our analysis indicates two possible scenarios for pair trajectories of catalytically active particles: either the particles approach, come into contact and assemble or they interact and move away from each other (escape). It is found that the direction of particle rotations is the key factor in determining the escape or assembly scenario due to an interplay between both hydrodynamic and phoretic effects. Based on the analysis, a phase diagram is sketched for the pair trajectory of the catalytically active particles as a function of reacting surface coverages and their initial relative orientations with respect to each other. We believe this study has important implications in elucidation of collective behaviours of autophoretically self-propelled colloids and would be certainly a guide for experimentalists to design and control active systems.

APA, Harvard, Vancouver, ISO, and other styles

38

Agudo-Canalejo, Jaime, and Ramin Golestanian. "Diffusion and steady state distributions of flexible chemotactic enzymes." European Physical Journal Special Topics 229, no. 17-18 (November 2020): 2791–806. http://dx.doi.org/10.1140/epjst/e2020-900224-3.

Full text

Abstract:

AbstractMany experiments in recent years have reported that, when exposed to their corresponding substrate, catalytic enzymes undergo enhanced diffusion as well as chemotaxis (biased motion in the direction of a substrate gradient). Among other possible mechanisms, in a number of recent works we have explored several passive mechanisms for enhanced diffusion and chemotaxis, in the sense that they require only binding and unbinding of the enzyme to the substrate rather than the catalytic reaction itself. These mechanisms rely on conformational changes of the enzyme due to binding, as well as on phoresis due to non-contact interactions between enzyme and substrate. Here, after reviewing and generalizing our previous findings, we extend them in two different ways. In the case of enhanced diffusion, we show that an exact result for the long-time diffusion coefficient of the enzyme can be obtained using generalized Taylor dispersion theory, which results in much simpler and transparent analytical expressions for the diffusion enhancement. In the case of chemotaxis, we show that the competition between phoresis and binding-induced changes in diffusion results in non-trivial steady state distributions for the enzyme, which can either accumulate in or be depleted from regions with a specific substrate concentration.

APA, Harvard, Vancouver, ISO, and other styles

39

Khair, Aditya S. "Diffusiophoresis of colloidal particles in neutral solute gradients at finite Péclet number." Journal of Fluid Mechanics 731 (August 14, 2013): 64–94. http://dx.doi.org/10.1017/jfm.2013.364.

Full text

Abstract:

AbstractThe role of neutral solute advection on the diffusiophoretic motion of colloidal particles is quantified. Theoretical analyses of this phenomenon usually assume that the solute concentration evolves solely via diffusion; that is, the Péclet number ($\mathit{Pe}$) for solute transport is identically zero. This leads to the conclusion that the translational diffusiophoretic velocity of a colloid is independent of its size, shape, and orientation with respect to the imposed solute gradient, provided that the colloid has uniform surface properties and that the length scale of interaction between the solute and the particle surface is much smaller than the particle size (Morrison, J. Colloid Interface Sci. vol. 34, 1970, p. 210). For a single spherical colloid, we show that the particle velocity decreases monotonically with increasing $\mathit{Pe}$. Moreover, the solute concentration and fluid flow around the colloid become markedly fore–aft asymmetric as $\mathit{Pe}$ is increased. Next, an asymptotic expansion at small $\mathit{Pe}$ predicts that solute advection leads to relative phoretic motion between two identical spherical colloids, which ultimately align in a plane normal to the imposed gradient (there is no relative motion at $\mathit{Pe}= 0$). Finally, asymptotic analysis of the diffusiophoretic motion of a slightly non-spherical colloid at small $\mathit{Pe}$ demonstrates that advection leads to a shape- and orientation-dependent particle velocity, in contrast to the insensitivity of the velocity to shape and orientation at $\mathit{Pe}= 0$.

APA, Harvard, Vancouver, ISO, and other styles

40

Fernández-Fernández, Mercedes, Pedro Naves, Dmitry L. Musolin, Andrey V. Selikhovkin, Michelle Cleary, Danut Chira, Marius Paraschiv, et al. "Pine Pitch Canker and Insects: Regional Risks, Environmental Regulation, and Practical Management Options." Forests 10, no. 8 (August 1, 2019): 649. http://dx.doi.org/10.3390/f10080649.

Full text

Abstract:

Pine pitch canker (PPC), caused by the pathogenic fungus Fusarium circinatum (Nirenberg and O’ Donnell), is a serious threat to pine forests globally. The recent introduction of the pathogen to Southern Europe and its spread in Mediterranean region is alarming considering the immense ecological and economic importance of pines in the region. Pines in forests and nurseries can be infected, resulting in severe growth losses and mortality. The pathogen is known to spread in plants for planting and in seeds, and results from recent studies have indicated that F. circinatum may also spread through phoretic associations with certain insects. With this review, we aim to expand the current understanding of the risk of insect-mediated spread of PPC in different parts of Europe. Through the joint action of a multinational researcher team, we collate the existing information about the insect species spectrum in different biogeographic conditions and scrutinize the potential of these insects to transmit F. circinatum spores in forests and nurseries. We also discuss the impact of environmental factors and forest management in this context. We present evidence for the existence of a high diversity of insects with potential to weaken pines and disseminate PPC in Europe, including several common beetle species. In many parts of Europe, temperatures are projected to rise, which may promote the activity of several insect species, supporting multivoltinism and thus, further amplifying the risk of insect-mediated dissemination of PPC. Integrated pest management (IPM) solutions that comply with forest management practices need to be developed to reduce this risk. We recommend careful monitoring of insect populations as the basis for successful IPM. Improved understanding of environmental control of the interaction between insects, the pathogen, and host trees is needed in order to support development of bio-rational strategies to safeguard European pine trees and forests against F. circinatum in future.

APA, Harvard, Vancouver, ISO, and other styles

41

Tomás, André, Maria Teresa Rebelo, Thijs Valkenburg, Michael Darby, and Isabel Pereira da Fonseca. "An Association between the Featherwing Beetle Ptiliolum fuscum (Erichson) (Coleoptera: Ptiliidae) and the Eurasian Griffon Gyps fulvus (Hablizi) (Accipitriformes: Accipitridae) – First Report of a Phoretic Interaction between Beetles and Birds?" Coleopterists Bulletin 72, no. 4 (December 28, 2018): 662. http://dx.doi.org/10.1649/0010-065x-72.4.662.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Khan, Shahid Ali, Bagh Ali, Chiak Eze, Kwun Ting Lau, Liaqat Ali, Jingtan Chen, and Jiyun Zhao. "Magnetic Dipole and Thermal Radiation Impacts on Stagnation Point Flow of Micropolar Based Nanofluids over a Vertically Stretching Sheet: Finite Element Approach." Processes 9, no. 7 (June 23, 2021): 1089. http://dx.doi.org/10.3390/pr9071089.

Full text

Abstract:

An analysis for magnetic dipole with stagnation point flow of micropolar nanofluids is modeled for numerical computation subject to thermophoresis, multi buoyancy, injection/suction, and thermal radiation. The partial derivative is involved in physical consideration, which is transformed to format of ordinary differential form with the aid of similarity functions. The variational finite element procedure is harnessed and coded in Matlab script to obtain the numerical solution of the coupled non-linear ordinary differential problem. The fluid temperature, velocity, tiny particles concentration, and vector of micromotion are studied for two case of buoyancy (assisting 0<λ, and opposing 0>λ) through finite-element scheme. The velocity shows decline against the rising of ferromagnetic interaction parameter (β) (assisting 0<λ and opposing 0>λ), while the inverse behaviour is noted in micro rotation profile. Growing the thermo-phoresis and microrotation parameters receded the rate of heat transfer remarkable, and micromotion and fluid velocity enhance directly against buoyancy ratio. Additionally, the rate of couple stress increased against rising of thermal buoyancy (λ) and boundary concentration (m) in assisting case, but opposing case shows inverse behavior. The finite element scheme convergency was tested by changing the mesh size, and also test the validity with available literature.

APA, Harvard, Vancouver, ISO, and other styles

43

Wagner, Martin, Sergi Roca-Bonet, and Marisol Ripoll. "Collective behavior of thermophoretic dimeric active colloids in three-dimensional bulk." European Physical Journal E 44, no. 3 (March 2021). http://dx.doi.org/10.1140/epje/s10189-021-00043-8.

Full text

Abstract:

Abstract Colloids driven by phoresis constitute one of the main avenues for the design of synthetic microswimmers. For these swimmers, the specific form of the phoretic and hydrodynamic interactions dramatically influences their dynamics. Explicit solvent simulations allow the investigation of the different behaviors of dimeric Janus active colloids. The phoretic character is modified from thermophilic to thermophobic, and this, together with the relative size of the beads, strongly influences the resulting solvent velocity fields. Hydrodynamic flows can change from puller-type to pusher-type, although the actual flows significantly differ from these standard flows. Such hydrodynamic interactions combined with phoretic interactions between dimers result in several interesting phenomena in three-dimensional bulk conditions. Thermophilic dimeric swimmers are attracted to each other and form large and stable aggregates. Repulsive phoretic interactions among thermophobic dimeric swimmers hinder such clustering and lead, together with long- and short-ranged attractive hydrodynamic interactions, to short-lived, aligned swarming structures. Graphic Abstract

APA, Harvard, Vancouver, ISO, and other styles

44

Roca-Bonet, Sergi, and Marisol Ripoll. "Self-phoretic Brownian dynamics simulations." European Physical Journal E 45, no. 3 (March 2022). http://dx.doi.org/10.1140/epje/s10189-022-00177-3.

Full text

Abstract:

Abstract A realistic and effective model to simulate phoretic Brownian dynamics swimmers based on the general form of the thermophoretic force is here presented. The collective behavior of self-phoretic dimers is investigated with this model and compared with two simpler versions, allowing the understanding of the subtle interplay of steric interactions, propulsion, and phoretic effects. The phoretic Brownian dynamics method has control parameters which can be tuned to closely map the properties of experiments or simulations with explicit solvent, in particular those performed with multiparticle collision dynamics. The combination of the phoretic Brownian method and multiparticle collision dynamics is a powerful tool to precisely identify the importance of hydrodynamic interactions in systems of self-phoretic swimmers. Graphic Abstract

APA, Harvard, Vancouver, ISO, and other styles

45

Liang, Huan, Peng Liu, Fangfu Ye, and Mingcheng Yang. "Active thermophoresis and diffusiophoresis." Chinese Physics B, June 2, 2022. http://dx.doi.org/10.1088/1674-1056/ac754d.

Full text

Abstract:

Abstract Thermo- and diffusiophoresis respectively refer to the directed drift of suspended particles in solutions with external thermal and chemical gradients, which have been widely used in the manipulation of mesoscopic particles. We here study a phoretic-like motion of a passive colloidal particle immersed in inhomogeneous active baths, where the thermal and chemical gradients are replaced separately by activity and concentration gradients of the active particles. By performing simulations, we show that the passive colloidal particle experiences phoretic-like forces that originate from its interactions with the inhomogeneous active fluid, and thus drifts along the gradient field, leading to an accumulation. The results are similar to the traditional phoretic effects occurring in passive colloidal suspensions, implying that the concepts of thermophoresis and diffusiophoresis could be generalized into active baths.

APA, Harvard, Vancouver, ISO, and other styles

46

Rojas-Pérez, Francisco, Blaise Delmotte, and Sébastien Michelin. "Hydrochemical interactions of phoretic particles: a regularized multipole framework." Journal of Fluid Mechanics 919 (May 26, 2021). http://dx.doi.org/10.1017/jfm.2021.387.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Choudhary, Akash, K. V. S. Chaithanya, Sébastien Michelin, and S. Pushpavanam. "Self-propulsion in 2D confinement: phoretic and hydrodynamic interactions." European Physical Journal E 44, no. 7 (July 2021). http://dx.doi.org/10.1140/epje/s10189-021-00101-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Lei, Lijie, Shuo Wang, Xuemao Zhou, Salah Eddine Ghellab, Guanhua Lin, and Yongxiang Gao. "Self-Organization of Binary Colloidal Mixtures via Diffusiohporesis." Frontiers in Chemistry 10 (March 10, 2022). http://dx.doi.org/10.3389/fchem.2022.803906.

Full text

Abstract:

Catalytic activity of the colloids and chemotactic response to gradients of the chemicals in the solution leads to effective interaction between catalytic colloids. In this paper, we simulate mixtures of active and passive colloids via a Brownian dynamics algorithm. These particles interact via phoretic interactions, which are determined by two independent parameters, surface activity and surface mobility. We find rich dynamic structures by tuning passive colloids’ surface mobility, size, and area fractions, which include schools of active colloids with exclusion zone, yolk/shell cluster, and stable active–passive alloys to motile clusters. Dynamical cluster can also be formed due to the nonreciprocity of the phoretic interaction. Increasing the size ratio of passive colloids to active colloids favors the phase separation of active and passive colloids, resulting in yolk/shell structure. Increasing the area fraction of active colloids tends to transfer from dynamical clusters into stable alloys. The simulated binary active colloid systems exhibit intriguing nonequilibrium phenomena that mimic the dynamic organizations of active/passive systems.

APA, Harvard, Vancouver, ISO, and other styles

49

Roca- Bonet, Sergi, Martin Wagner, and Marisol Ripoll. "Clustering of self-thermophilic asymmetric dimers: the relevance of hydrodynamics." Soft Matter, 2022. http://dx.doi.org/10.1039/d2sm00523a.

Full text

Abstract:

Self-thermophilic dimers are characterized by a net phoretic attraction which, in combination with hydrodynamic interactions, results into the formation of crystalline-like aggregates. To distinguish the effect of the different contributions...

APA, Harvard, Vancouver, ISO, and other styles

50

Lisicki, Maciej, Sébastien Michelin, and Eric Lauga. "Phoretic flow induced by asymmetric confinement." Journal of Fluid Mechanics 799 (June 28, 2016). http://dx.doi.org/10.1017/jfm.2016.408.

Full text

Abstract:

Internal phoretic flows due to the interactions of solid boundaries with local chemical gradients may be created using chemical patterning. Alternatively, we demonstrate here that internal flows might also be induced by geometric asymmetries of chemically homogeneous surfaces. We characterise the circulatory flow created in a cavity enclosed between two eccentric cylindrical walls of uniform chemical activity. Local gradients of the diffusing solute induce a slip flow along the surface of the cylinders, leading to a circulatory bulk flow pattern which can be solved analytically in the diffusive limit. The flow strength can be controlled by adjusting the relative positions of the cylinders, and an optimal configuration is identified. These results provide a model system for tunable phoretic pumps.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Phoretic interactions'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles