scholarly journals The cleaner shrimp Lysmata amboinensis adjusts its behaviour towards predatory versus non-predatory clients

2019 ◽  
Vol 15 (9) ◽  
pp. 20190534
Author(s):  
Eleanor M. Caves ◽  
Catherine Chen ◽  
Sönke Johnsen
Keyword(s):  
Predation Risk ◽  
Fish Species ◽  
Potential Risk ◽  
Laboratory Experiments ◽  
Visual Stimuli ◽  
Lower Proportion ◽  
Illumination Level ◽  
Marine Crustaceans ◽  
Cleaner Shrimp

In cleaning mutualisms, small cleaner organisms remove ectoparasites and dead skin from larger clients. Because cheating by predatory clients can result in cleaner death, cleaners should assess the potential risk of interacting with a given client and adjust their behaviour accordingly. Cleaner shrimp are small marine crustaceans that interact with numerous client fish species, many of which are potential predators. We use in situ observations of cleaner–client interactions to show that the cleaner shrimp Lysmata amboinensis adjusts several behaviours when interacting with predatory versus non-predatory clients. Predatory clients were cleaned in a significantly lower proportion of interactions than non-predatory clients, and cleaners also exhibited a leg rocking behaviour—potentially signalling their identity or intent to clean—almost exclusively toward predatory clients. Incidence of leg rocking was positively correlated with client size, and laboratory experiments showed that it can be elicited by dark visual stimuli and decreases in illumination level. Thus, cleaners clean less frequently when predation risk is higher, and may use leg rocking as a signal advertising cleaning services and directed specifically at predators.

scholarly journals Mutual visual signalling between the cleaner shrimp Ancylomenes pedersoni and its client fish

2018 ◽  
Vol 285 (1881) ◽  
pp. 20180800 ◽  
Author(s):  
Eleanor M. Caves ◽  
Patrick A. Green ◽  
Sönke Johnsen
Keyword(s):  
Sequential Analysis ◽  
Visual Stimuli ◽  
Colour Change ◽  
Mutualistic Interaction ◽  
Dark Colour ◽  
Behavioural Interactions ◽  
Visual Signalling ◽  
Fish Clients ◽  
Cleaner Shrimp

Cleaner shrimp and their reef fish clients are an interspecific mutualistic interaction that is thought to be mediated by signals, and a useful system for studying the dynamics of interspecific signalling. To demonstrate signalling, one must show that purported signals at minimum (a) result in a consistent state change in the receiver and (b) contain reliable information about the sender's intrinsic state or future behaviour. Additionally, signals must be perceptible by receivers. Here, we document fundamental attributes of the signalling system between the cleaner shrimp Ancylomenes pedersoni and its clients. First, we use sequential analysis of in situ behavioural interactions to show that cleaner antenna whipping reliably predicts subsequent cleaning. If shrimp do not signal via antenna whipping, clients triple their likelihood of being cleaned by adopting darker coloration over a matter of seconds, consistent with dark colour change signalling that clients want cleaning. Using experimental manipulations, we found that visual stimuli are sufficient to elicit antenna whipping, and that shrimp are more likely to ‘clean' dark than light visual stimuli. Lastly, we show that antenna whipping and colour change are perceptible when accounting for the intended receiver's visual acuity and spectral sensitivity, which differ markedly between cleaners and clients. Our results show that signalling by both cleaners and clients can initiate and mediate their mutualistic interaction.

scholarly journals Listener-Position and Orientation Dependency of Auditory Perception in an Enclosed Space: Elicitation of Salient Attributes

2021 ◽  
Vol 11 (4) ◽  
pp. 1570
Author(s):  
Bogdan Ioan Băcilă ◽  
Hyunkook Lee
Keyword(s):  
Auditory Perception ◽  
Laboratory Experiments ◽  
Head Orientation ◽  
Repertory Grid Technique ◽  
Apparent Source ◽  
Grid Technique ◽  
Subjective Study ◽  
Enclosed Space ◽  
Orientation Dependency

This paper presents a subjective study conducted on the perception of auditory attributes depending on listener position and head orientation in an enclosed space. Two elicitation experiments were carried out using the repertory grid technique—in-situ and laboratory experiments—which aimed to identify perceptual attributes among 10 different combinations of the listener’s positions and head orientations in a concert hall. It was found that, between the in-situ and laboratory experiments, the listening positions and head orientations were clustered identically. Ten salient perceptual attributes were identified from the data obtained from the laboratory experiment. Whilst these included conventional attributes such as ASW (apparent source width) and LEV (listener envelopment), new attributes such as PRL (perceived reverb loudness), ARW (apparent reverb width) and Reverb Direction were identified, and they are hypothesised to be sub-attributes of LEV (listener envelopment). Timbral characteristics such as Reverb Brightness and Echo Brightness were also identified as salient attributes, which are considered to potentially contribute to the overall perceived clarity.

scholarly journals Natural dimethyl sulfide gradients would lead marine predators to higher prey biomass

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Kylie Owen ◽  
Kentaro Saeki ◽  
Joseph D. Warren ◽  
Alessandro Bocconcelli ◽  
David N. Wiley ◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Dimethyl Sulfide ◽  
Zooplankton Biomass ◽  
Foraging Success ◽  
Spatially Correlated ◽  
Prey Biomass ◽  
Marine Predators ◽  
Predator Foraging ◽  
The Impact

AbstractFinding prey is essential to survival, with marine predators hypothesised to track chemicals such as dimethyl sulfide (DMS) while foraging. Many predators are attracted to artificially released DMS, and laboratory experiments have shown that zooplankton grazing on phytoplankton accelerates DMS release. However, whether natural DMS concentrations are useful for predators and correlated to areas of high prey biomass remains a fundamental knowledge gap. Here, we used concurrent hydroacoustic surveys and in situ DMS measurements to present evidence that zooplankton biomass is spatially correlated to natural DMS concentration in air and seawater. Using agent simulations, we also show that following gradients of DMS would lead zooplankton predators to areas of higher prey biomass than swimming randomly. Further understanding of the conditions and scales over which these gradients occur, and how they are used by predators, is essential to predicting the impact of future changes in the ocean on predator foraging success.

scholarly journals Combined effect of risk type and activity rhythm on anti-predator response of the shore crab Gaetice depressus (Crustacea: Grapsidae)

2006 ◽  
Vol 86 (6) ◽  
pp. 1401-1405 ◽  
Author(s):  
Ryo Sakamoto ◽  
Atsushi Ito ◽  
Satoshi Wada
Keyword(s):  
Predation Risk ◽  
Laboratory Experiments ◽  
Activity Rhythm ◽  
Combined Effect ◽  
Shore Crab ◽  
Octopus Vulgaris ◽  
Active Period ◽  
Inactive Period ◽  
Predator Response ◽  
Chemical Stimuli

The response of the shore crab Gaetice depressus to predation risk stimuli of either the octopus Octopus vulgaris or crushed conspecifics was examined at two different time phases in the activity rhythm (active and inactive period) by laboratory experiments. When octopus chemical stimuli were introduced to the experimental aquarium, the crab activity decreased in the active period (night) but not in the inactive period (daytime). When the chemical stimuli of crushed G. depressus were introduced, the activity of the crabs increased in the inactive period although the stimuli decreased the activity in the active period. This indicates that G. depressus adjust their anti-predator response according to a combination of the type of predation risk and also the activity rhythm.

Analysis of the World's First Polymer Injectivity Test in a Carbonate Reservoir Under Extreme Harsh Conditions in ADNOC's Reservoirs

2021 ◽  
Author(s):  
Juan Manuel Leon ◽  
Shehadeh K. Masalmeh ◽  
Siqing Xu ◽  
Ali M. AlSumaiti ◽  
Ahmed A. BinAmro ◽  
...  
Keyword(s):  
High Temperature ◽  
Laboratory Experiments ◽  
High Salinity ◽  
Laboratory Data ◽  
Injection Pressure ◽  
Carbonate Reservoir ◽  
Experimental Program ◽  
Full Field ◽  
Harsh Conditions

Abstract Assessing polymer injectivity for EOR field applications is highly important and challenging. An excessive injectivity reduction during and after polymer injection may potentially affect the well integrity and recovery efficiency and consequently, injection strategy and the economics of the polymer projects. Moreover, well conditions such as skin, completion configuration, and injection water quality can significantly impact polymer injectivity. Additionally, the presence of fractures or micro-fractures may govern injection pressure. In contrast, historic field applications have shown that polymer injectivity is in general better than expected from simulations or laboratory data. In the laboratory experiments, the polymer injectivity has been evaluated by injection of significant amounts of pore volumes of polymer at relevant well-injection rates. In addition, several experiments were performed to measure the complex in-situ rheology expected to dominate the flow near the wellbore This paper presents the analysis of the the world's first polymer injectivity test (PIT) conducted in a high temperature and high salinity (HTHS) carbonate reservoir in Abu Dhabi as part of a comprehensive de-risking program for a new polymer-based EOR scheme proposed by ADNOC for these challenging carbonate reservoirs (see Masalmeh et. al., 2014). The de-risking program includes an extensive laboratory experimental program and field injectivity test to ensure that the identified polymer can be injected and propagated in the target formation before multi-well pilot and full-field implementation stages. Experimental laboratory data and the field injectivity test results are presented in earlier publications (Masalmeh et. al., 2019; Rachapudi et. al., 2020) and references therein. This PIT is the world's first polymer injectivity test in a carbonate reservoir under such harsh conditions of high salinity, high content of divalent ions and high temperature. In addition, the polymer used during the test has never been field-tested before. Therefore, the results of the PIT interpretation will help to de-risk the suitable polymer for the future inter-well pilot for the new proposed EOR Polymer-based scheme and it is a game-changer to unlock several opportunities for different Chemical EOR applications on full-field scale in other reservoirs with similar characteristics. A single well radial simulation model was built to integrate the surveillance data during PIT and the extensive laboratory experiments. Morever, multiple Pressure Fall Off Tests (PFOs) during the same periods were analyzed and intergaretd in the model.The study assessed the effect of polymer viscosity on mobility reduction, evaluated the polymer bank propagation, investigated the effect of the skin build-up, residual resistance factor (RRF) and shear effects on the well injectivity. Additionally, a comprehensive assisted history match method and robust simulation sensitivity analysis was implemented, thousands of sensitivity simulation runs were performed to capture several possible injection scenarios and validate laboratory parameters. The simulation study confirmed that the PIT could be interpreted using the laboratory-measured polymer parameters such as polymer bulk viscosity, in-situ rheology, RRF and adsorption.

scholarly journals Laboratory Evaluation and Construction of Fully Recycled Low-Temperature Asphalt for Low-Volume Roads

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Christiane Raab ◽  
Manfred N. Partl
Keyword(s):  
Ambient Temperature ◽  
Laboratory Experiments ◽  
Traffic Simulation ◽  
Traffic Load ◽  
Laboratory Evaluation ◽  
Small Scale ◽  
Medium Scale ◽  
Low Volume Roads ◽  
Low Volume

Growing economy and increasing pollution evoke the need for more environmentally friendly road construction techniques and the saving of natural resources. In this context, cold recycling plays an important role since, on the one hand, it allows to reduce CO2 emissions drastically and, on the other hand, it offers a variety of opportunities for high percentages of recycling. Inspired by experience in Sweden, the international project “Optimal Recycling of Reclaimed Asphalts for low-traffic Pavement” (ORRAP) for low-volume roads in the Upper Rhine region aims to develop and establish a new strategy for 100% reclaimed asphalt pavement (RAP) at ambient temperature (20°C) without adding virgin bituminous binders or rejuvenators. The still ongoing research project involves laboratory experiments as well as in situ test sections. The link between small-scale laboratory experiments and in situ testing is provided by medium-scale traffic simulation in the laboratory. This paper describes results from medium-scale compaction in the laboratory using different methods as well as traffic simulation with a medium-scale mobile traffic load simulator. The results show that compaction in the laboratory at ambient temperature (20°) is very difficult to achieve. Nevertheless, it was found that compaction at a temperature of 60°C appears possible and provides promising results regarding stability and rutting enabling the in situ construction. The in situ pavement construction at ambient temperature on a low-volume road in Switzerland resulted in a visibly well-compacted and stable base course which was covered by a hot mix asphalt surface course the day after. The test section will be monitored closely over the next 12 months.

Effects of 17β-estradiol injection and red-spectrum light on eyestalk hormones and vitellogenesis of the ornamental cleaner shrimp Lysmata amboinensis (De Man, 1888) (Decapoda: Caridea: Lysmatidae)

2019 ◽  
Author(s):  
Ji Yong Choi ◽  
Cheol Young Choi ◽  
Min-Min Jung
Keyword(s):  
Mrna Expression ◽  
Red Light ◽  
Crustacean Hyperglycemic Hormone ◽  
Eyestalk Ablation ◽  
Vitellogenin Receptor ◽  
Hyperglycemic Hormone ◽  
17Β Estradiol ◽  
De Man ◽  
Cleaner Shrimp

Abstract We analyzed the effects of 17β-estradiol (E2) injection and red light on the sexual maturation and vitellogenesis of the cleaner shrimp Lysmata amboinensis (De Man, 1888) by measuring the change of mRNA expression levels of eyestalk and vitellogenesis-related hormones induced by both factors. We examined the eyestalk crustacean hyperglycemic hormone (CHH) and vitellogenesis-inhibiting hormone (VIH) genes. The E2 injection did not affect changes of eyestalk hormones. The red light, however, caused a significant increase (P < 0.05) of CHH promoting maturity and a significant decrease of VIH, which suppressed vitellogenesis. The vitellogenin receptor (VTG-R) and mRNA expression (in situ hybridization) also caused the E2 injection and red-wavelength irradiation to induce synthesis of vitellogenin (VTG). Red-light-induced gonadal maturation, promoting hormone and VTG synthesis, but E2 did not change the eyestalk hormone. Red-light irradiation could thus be used as a novel, maturity-promoting alternative method in the culture of the species, which is different from the eyestalk-ablation method that has so far been used.

Upscaling Kinetics for Field-Scale In-Situ-Combustion Simulation

2015 ◽  
Vol 18 (02) ◽  
pp. 158-170 ◽  
Author(s):  
Anna Nissen ◽  
Zhouyuan Zhu ◽  
Anthony Kovscek ◽  
Louis Castanier ◽  
Margot Gerritsen
Keyword(s):  
Laboratory Experiments ◽  
Two Dimensions ◽  
Work Flow ◽  
Arrhenius Kinetics ◽  
In Situ Combustion ◽  
Performance Improvements ◽  
Combustion Simulation ◽  
New Formulation ◽  
Combustion Processes

Summary We demonstrate the effectiveness of a non-Arrhenius kinetic upscaling approach for in-situ-combustion processes, first discussed by Kovscek et al. (2013). Arrhenius reaction terms are replaced with equivalent source terms that are determined by a work flow integrating both laboratory experiments and high-fidelity numerical simulations. The new formulation alleviates both stiffness and grid dependencies of the traditional Arrhenius approach. Consequently, the computational efficiency and robustness of simulations are improved significantly. In this paper, we thoroughly investigate the performance of the non-Arrhenius upscaling method compared with Arrhenius kinetics. We investigate robustness by considering grid effects and sensitivity to heterogeneity. Performance improvements of the new kinetic upscaling approach compared with traditional Arrhenius kinetics are demonstrated through numerical experiments in one and two dimensions for both homogeneous- and heterogeneous-permeability fields.

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