Search results for "Laboratory experiment"

showing 10 items of 67 documents

Emigration speed and the production of sexuals in colonies of the ant Temnothorax crassispinus under high and low levels of disturbance

2015

A nest relocation is costly for social insects, and involves hazards. Emigrations were studied in Temnothorax crassispinus ant colonies, which inhabit ephemeral nest sites, and which frequently change their nests. In a laboratory experiment, ant colonies from one group were forced to change their nest sites 10 times over a ca. 3-month period, whilst colonies from the second group were forced to adopt this practice twice (on the beginning of May, and in the second half of July). Colonies of the ant from both the groups reduced their total emigration duration. However, the duration of the transport phase remained unchanged. In the case of colonies with higher level of disturbance, there was n…

0106 biological sciencesDisturbance (geology)Social insectEcology05 social sciencesTemnothorax crassispinusNest movementAnt colonyBiology010603 evolutionary biology01 natural sciencesEnergy allocationANTEmigrationNestColony sizeInsect Science0501 psychology and cognitive sciences050102 behavioral science & comparative psychologyLaboratory experimentEnergy allocationEcology Evolution Behavior and SystematicsResearch ArticleInsectes Sociaux
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Effects of starvation on survival, cannibalism, body mass, and intestinal protozoan profile in the subterranean termite Reticulitermes lucifugus

2019

Scarcity or inadequate nutrition can affect biological and behavioural aspects of subterranean termites and their intestinal protozoan profile. The aim of this study was to investigate changes in survival, cannibalism, body mass, and protist community structure of Reticulitermes lucifugus Rossi subspecies “Sicily” following starvation to provide basic knowledge for the development of more specific studies on a possible survival strategy under stressful conditions. In nature, this termite consumes many food sources and its feeding activity is continuous during the year. In a 35-day laboratory experiment, groups of 50 termites (worker/soldier ratio 49:1) were subjected to two diets, starvatio…

0106 biological sciencesStarvationSocial insectProtistInadequate nutritionCannibalismBehaviour changeZoologySurvivorshipBiologyIntestinal protozoan010603 evolutionary biology01 natural sciences010602 entomologySettore AGR/11 - Entomologia Generale E ApplicataBasic knowledgeInsect ScienceSurvivorship curveSurvival strategymedicineReticulitermes lucifugusmedicine.symptomLaboratory experimentEcology Evolution Behavior and SystematicsInsectes Sociaux
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Limiting Liability? — Risk and Ambiguity Attitudes Under Real Losses

2013

Using a laboratory experiment in which the unlimited liability treatment involves real out-of-pocket losses, we investigate and compare the behavioral effects of auditors’ limited and unlimited liability on behavior under risk and ambiguity. We find that aversion to both risk and ambiguity are higher under unlimited liability than under limited liability, and that these two constructs are correlated under unlimited liability. Our findings explain why some auditors might be hindered in performing their duties properly under unlimited liability. Further, our findings emphasize the importance of appropriately modeling risk and ambiguity attitudes in economic models on liability.

Actuarial scienceLimited liabilitymedia_common.quotation_subjectLiabilityGeneral EngineeringProduction (economics)Economic modelLimitingAmbiguityBusinessAuditLaboratory experimentmedia_commonSchmalenbach Business Review
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Natural versus enriched food: Evidence from a laboratory experiment with chewing gum.

2019

Abstract The current study explored consumers' preferences for natural versus enriched foods and identified the underlying driving forces behind consumer interest towards both attributes. A laboratory experiment with 200 respondents was carried out, applying the incentive compatible Becker-DeGroot-Marschak mechanism to measure consumers' willingness to pay for natural and enriched attributes of chewing gum. Empirical findings reveal that the two attributes are evaluated similarly by consumers. Furthermore, structural equation modelling identified a strong interdependence between the natural and the enriched attributes, suggesting they are complementary rather than substitutes/alternatives i…

AdultMaleEnriched FoodEnrichedAdolescentStructural equation modelingChewing GumFood PreferencesYoung AdultWillingness to paySurveys and QuestionnairesSettore AGR/01 - Economia Ed Estimo RuraleFood choiceNatural (music)HumansWillingness to payMarketingBDM mechanismConsumer BehaviorChewing gumConsumer preferenceIncentive compatibilityStructural equation modellingResearch DesignFood FortifiedNaturalFemaleLaboratory experimentPsychologyFood ScienceFood research international (Ottawa, Ont.)
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Disclosing Conflict of Interest - Do Experience and Reputation Matter?

2009

In a controlled laboratory experiment, we investigate the effects of disclosing conflicts of interest on the reporting of information providers. First, we replicate the findings of Cain, Loewenstein, and Moore (2005) that such disclosure makes misreporting more likely as it removes moral concerns. Second, we observe that these effects diminish given experience and find, to the opposite, that disclosure reduces bias in auditors' reporting as predicted by economic theory. Third, we identify disclosure of conflicts of interest as a potential impediment to reputation formation.

Auditor's reportActuarial sciencebusiness.industrymedia_common.quotation_subjectConflict of interestAccountingAuditExperimental economicsAuditor independenceInformation providersComputingMilieux_COMPUTERSANDSOCIETYBusinessLaboratory experimentReputationmedia_commonSSRN Electronic Journal
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Experimental observations of upstream overdeepening

2005

The issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence, depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels, while narrower stream…

BedformMechanics of MaterialsMechanical EngineeringOverdeepeningThe issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels while narrower streams are dominated by downstream influence. A series of experiments has been carried out in order to check the above theoretical predictions and show for the first time evidence of the occurrence of upstream overdeepening. Two different sets of experiments have been designed where a discontinuity in channel geometry was present such that the channel morphodynamics was influenced in the upstream direction under super-resonant conditions (β >βR) and in the downstream direction under sub-resonant conditions (β <βR). Experimental results give qualitative and quantitative support to the theoretical predictions and allow us to clarify the limits of the linear analysis.MechanicsLinear analysisCondensed Matter PhysicsWidth ratioGeology
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Experimental conditions for respiration and growth studies of F0 and F1 larval and juvenile European seabass Dicentrarchus labrax

2022

Water parameters in the 2 years before spawning of F0 (08.02.2016-06.03.2018) and during larval and juvenile phase of F1: Larval period until 17.05.2018 (48 dph, 900 dd) and 01.06.2018 (63 dph, ~900 dd) for warm and cold life condition respectively, for the juveniles until 28.09.2018 (180 dph, ~4000 dd) and 12.02.2019 (319 dph, ~5100 dd) for warm and cold conditioned fish respectively. Means ± s.e. over all replicate tanks per condition. Temperature (Temp.), pH (free scale), salinity, oxygen and total alkalinity (TA) were measured weekly in F1 and monthly in F0; sea water (SW) measurements were conducted in 2017 and 2018. Water parameters during larval and early juvenile phase of F0: Larval…

Calculated by CO2sys_xls_program Lewis and WallaceSalinityAlkalinityLife stageType of studyTemperature waterGermanyCalculatedAlkalinity totalSalinity standard errortotallarval growthteleostexperiment2006pH2007 with purified m cresol purpleOcean acidificationMeasured spectrophotometrically Dickson et alTemperatureWeilheimPartial pressure of carbon dioxide (water) at sea surface temperature (wet air) standard errorSilicatedissolvedLaboratory experimentSEAL AA3 segmented flow autoanalyzerSilicate standard errorstandard errorMultiprobeEarth System ResearchWTW 340imetabolic rateswaterGenerationOxygen dissolvedMultiprobe WTW 340iPhosphateocean warmingAlkalinity total standard errorjuvenile growthCarbon dioxide (water) partial pressurepH meter (WTW 3110) with electrode (WTW Sentix 41)DATE TIMEWTW Oxi 340i probeTemperature water standard errorCarbon dioxide water partial pressurepH standard errorXylem Analytics GermanySalinometer (WTW LF325 Xylem Analytics Germany Weilheim Germany)Calculated by CO2sys_xls_program (Lewis and Wallace 2006)OxygenTreatmentDATE/TIMEPartial pressure of carbon dioxide water at sea surface temperature wet airSalinometer WTW LF325Oxygen dissolved standard errorMeasured spectrophotometrically (Dickson et al. 2007) with purified m-cresol purplepH meter WTW 3110 with electrode WTW Sentix 41Phosphate standard error
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A laboratory study on the scavenging of SO2 by snow crystals

1990

Abstract A laboratory experiment is described where the uptake of SO2 by dendritic snow crystals was studied. In a first experimental series the uptake of SO2 was investigated during the growth of the snow crystals from water vapor with and without the presence of H2O2 in the air. In a second series of experiments we studied the uptake of SO2 by snow crystals which had completed their growth. The results of our experiments showed that under both conditions SO2 became scavenged by snow crystals. The uptake of SO2 was particularly pronounced during the growth of the snow crystals, and at temperatures close to 0°C where a quasi-liquid layer exists at the surface of ice. As expected, the SO2 up…

ChemistryAnalytical chemistryGeneral Earth and Planetary SciencesAcid rainLaboratory experimentAtmospheric sciencesSnowcomplex mixtureshuman activitiesScavengingWater vaporrespiratory tract diseasesGeneral Environmental ScienceAtmospheric Environment. Part A. General Topics
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Too Much or Too Little Messaging? Situational Determinants of Guilt About Mobile Messaging

2021

Abstract Mobile messaging has been associated with guilt. Guilt about too much messaging may result from self-control failures during goal conflicts. Conversely, guilt about too little messaging may result from violating the salient norm to be available. This research considers both boundary conditions of guilt about mobile communication—goal conflicts and availability norm salience—simultaneously for the first time. We conducted two preregistered experiments to investigate their interplay. Results from a vignette experiment, but not from a laboratory experiment, support the hypotheses that goal conflicts trigger guilt about using messengers and that guilt about not using messengers arises …

Computer Networks and Communications05 social sciences050801 communication & media studies050109 social psychologyComputer Science Applications0508 media and communicationsMobile mediaNorm (artificial intelligence)VignetteSalient0501 psychology and cognitive sciencesLaboratory experimentSituational ethicsPsychologySocial psychologyJournal of Computer-Mediated Communication
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Modelling thermionic emission by using a two Level mechanical system

2008

The Boltzmann factor is at the basis of a great amount of thermodynamic and statistical physics, both classical and quantum. It describes the behaviour of natural systems that exchange energy with the environment. However, why does the expression have that specific form? The Feynman Lectures on Physics justifies it heuristically by referencing to the "exponential atmosphere" example. Thermodynamics textbooks usually give a more or less complete explanation that mainly involves a mathematical analysis, where it is hard to see the logic flow. Moreover, the necessary mathematics is not at the level of high school or college students' preparation. Here we present an experiment and a simulation …

Computers in educationSettore FIS/08 - Didattica E Storia Della FisicaLaboratory experiments and apparatusTeaching methods and strategieEducation
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