scholarly journals Crowdsourcing visual perception experiments: a case of contrast threshold

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e8339 ◽  
Author(s):  
Kyoshiro Sasaki ◽  
Yuki Yamada
Keyword(s):  
Visual Perception ◽  
Laboratory Experiment ◽  
Psychological Research ◽  
Small Sample ◽  
The Other ◽  
Contrast Threshold ◽  
Repetition Condition ◽  
Experimental Conditions ◽  
Online Experiments ◽  
Contrast Thresholds

Crowdsourcing has commonly been used for psychological research but not for studies on sensory perception. A reason is that in online experiments, one cannot ensure that the rigorous settings required for the experimental environment are replicated. The present study examined the suitability of online experiments on basic visual perception, particularly the contrast threshold. We conducted similar visual experiments in the laboratory and online, employing three experimental conditions. The first was a laboratory experiment, where a small sample of participants (n = 24; laboratory condition) completed a task with 10 iterations. The other two conditions were online experiments: participants were either presented with a task without repetition of trials (n = 285; online non-repetition condition) or one with 10 iterations (n = 166; online repetition condition). The results showed significant equivalence in the contrast thresholds between the laboratory and online repetition conditions, although a substantial amount of data needed to be excluded from the analyses in the latter condition. The contrast threshold was significantly higher in the online non-repetition condition compared with the laboratory and online repetition conditions. To make crowdsourcing more suitable for investigating the contrast threshold, ways to reduce data wastage need to be formulated.

scholarly journals Finding domain-general metacognitive mechanisms requires using appropriate tasks

2017 ◽  
Author(s):  
Eugene Ruby ◽  
Nathan Giles ◽  
Hakwan Lau
Keyword(s):  
Visual Perception ◽  
Sample Size ◽  
False Positive ◽  
Statistical Power ◽  
Forced Choice ◽  
The Other ◽  
Online Experiments ◽  
Positive Correlation ◽  
Domain Specific ◽  
Unresolved Question

AbstractAn important yet unresolved question is whether or not metacognition consists of domain-general or domain-specific mechanisms. While most studies on this topic suggest a dissociation between metacognitive abilities at the neural level, there are conflicting reports at the behavioral level. Specifically, while McCurdy et al. (2013) found a positive correlation between metacognitive efficiency for visual perception and memory, Baird et al. (2013) didn’t find this correlation. One possible explanation for this disparity is that the former included two-alternative-forced choice (2AFC) judgments in both their visual and memory tasks, whereas the latter used 2AFC for one task and yes/no (YN) judgments for the other. In support of this hypothesis, we ran two online experiments meant to mirror McCurdy et al. (2013) and Baird et al. (2013) with considerable statistical power (n=100), and replicated the main findings of both studies. This suggests the finding of McCurdy et al (2013) was not a ‘fluke’ (i.e. false positive). In a third experiment with the same sample size, which included YN judgments for both tasks, we did not find a correlation between metacognitive functions, suggesting that the conflict between McCurdy et al. (2013) and Baird et al. (2013) stemmed from the use of YN judgments in the latter study. Our results underscore the need to avoid conflating 2AFC and YN judgments, which is a common problem.

Intercalation Processes in Cobalt Substituted Nickel Oxyhydroxides

1990 ◽  
Vol 210 ◽  
Author(s):  
Claude Delmas
Keyword(s):  
Ir Spectroscopy ◽  
Mechanical Treatment ◽  
Positive Charge ◽  
Van Der Waals ◽  
The Other ◽  
Hydrolysis Reaction ◽  
Water Molecules ◽  
Layered Oxides ◽  
Experimental Conditions ◽  
Cobalt Ions

AbstractChimie douce reactions (hydrolysis and reduction) from layered oxides : NaNiO2, NaxCoO2 and NaNil-xCoxO2 lead to numerous oxyhydroxides and hydroxides which differ by the composition of the intersheet space.According to the experimental conditions of the hydrolysis reaction, the oxyhydroxides can be unhydrated or intercalated with one or two layers of water molecules. From the most hydrated phases, the other ones can be obtained by chemical, thermal and even mechanical treatment.The reduction of Co-substituted nickel oxyhydroxides leads to hydroxides in which nickel and cobalt ions are respectively divalent and trivalent. In order to compensate the excess of positive charge in the (Ni, Co)O2 sheet, anions (OH-, CO32-, SO42-, NO3-) are inserted in the Van der Waals gap.For the highest anion amounts, well ordered α*-type materials are obtained. Water molecules are simultaneously inserted in the interslab space. Their structure is strongly related to the hydrotalcite one. When the amouit of anions in the intersheet space is not sufficient, interstratified materials are obtained. In this case the (Ni,Co)(OH)2 slabs are separated by a layer of CO32- anions and water molecules (α*-type) or by an empty Van der Waals gap (β(II)-type). The amount of α*-type planes in the structure increases with the cobalt amount. All these materials have been characterized by IR spectroscopy which allows to detect the existence of two types of O-H bonds (free in α*-type plane or hydrogen bonded in ²(II)-type plane).

In Vitro Binding of Zearalenone to Different Adsorbents

2005 ◽  
Vol 68 (3) ◽  
pp. 613-615 ◽  
Author(s):  
DANTE J. BUENO ◽  
LILIANA DI MARCO ◽  
GUILLERMO OLIVER ◽  
ALICIA BARDÓN
Keyword(s):  
Activated Carbon ◽  
Calcium Sulfate ◽  
Fusarium Species ◽  
The Other ◽  
Experimental Conditions ◽  
In Vitro Binding ◽  
Other Hand ◽  
Vitro Binding ◽  
Dose Levels

Zearalenone (ZEA) is a potent estrogenic metabolite produced by some Fusarium species. No treatment has been successfully employed to get rid of the ZEA contained in foods. This study was conducted to evaluate the ability (adsorptive power) of five adsorbents—activated carbon, bentonite, talc, sandstone, and calcium sulfate—to trap ZEA in vitro. Activated carbon was the best adsorbent, binding 100% ZEA (pH 3 and 7.3) at 0.1, 0.25, 0.5, and 1% dose levels. Bentonite, talc, and calcium sulfate were less efficient than activated carbon but still could bind ZEA to some extent. On the other hand, sandstone was inactive in the experimental conditions employed. Our results indicate that activated carbon could be a good candidate for detoxification of ZEA present in foods.

The Effects of Adverse Environmental Conditions on Workload

1975 ◽  
Vol 19 (3) ◽  
pp. 301-304
Author(s):  
Ann E. Martin
Keyword(s):  
Environmental Conditions ◽  
Environmental Variables ◽  
Secondary Task ◽  
The Other ◽  
Random Numbers ◽  
Performance Decrement ◽  
Experimental Conditions ◽  
Continuous Noise ◽  
Adverse Environmental Conditions ◽  
Intermittent Noise

The present study was conducted to investigate the effects of environmental conditions on visual workload. The environmental variables used were temperature, studied at levels of 45°F., WBGT, and 95°F., WBGT; and noise, studied at 83 dBA intermittent noise and 93 dBA continuous noise. Workload was defined as the amount of attention demanded from an operator as measured by performance decrement on a secondary task while performing a primary and secondary task simultaneously. The secondary task was reading random numbers, and the primary task was reading word lists. Significant differences (p<.05) were found between the control condition and all experimental conditions. The low temperature and high temperature-continuous noise conditions were significantly different from the other conditions. Noise and temperature were found to significantly increase workload (p<05).

scholarly journals Cultivation of Milky Mushroom (Calocybeindica) in Greenhouse

2021 ◽  
pp. 63-69
Author(s):  
P. Indraja ◽  
M. Madhava ◽  
S. Satyam ◽  
P. R. Chandra ◽  
S. Joy Prince
Keyword(s):  
Relative Humidity ◽  
Traditional Method ◽  
Large Scale ◽  
Nutritive Value ◽  
Edible Mushroom ◽  
Atmospheric Temperature ◽  
The Other ◽  
Controlled Environment ◽  
Mushroom Cultivation ◽  
Experimental Conditions

Mushroom cultivation is one of the most important steps in diversification of agriculture. Milky mushroom (Calocybeindica) is a tropical edible mushroom, popular because of its good nutritive value and it can be cultivated commercially on large scale. Generally, by creating controlled environment in rooms mushroom cultivation is taken up, In traditional method  it is typical to manage the atmospheric temperature and humidity in desired range, which can be maintained easily in greenhouse by automatic control system.Cultivation of milky mushroom in greenhouse was taken up in controlled environment under three different conditions of controlled temperature and relative humidity (RH). The experimental conditions are 28°C and 79% RH, 24°C and 84% RH and 32°C and 72%RH. The yield obtained was found maximum at 24°C temperature and 84% relative humidity when compared with the other two greenhouse environment conditions. The yield from the mushroom cultivation under controlled environmental conditions in greenhouse was found to be high when compared with the conventional practice. It was concluded that, the mushroom cultivation yields high under controlled greenhouse conditions and also economical compared to the conventional method.

scholarly journals Dynamic Guidance by Colored Running Lights and Affordance: Route Choices of Adults and Older Children

2020 ◽  
Vol 5 ◽  
Author(s):  
Laura Künzer ◽  
Robert Zinke ◽  
Gesine Hofinger
Keyword(s):  
Laboratory Experiment ◽  
Route Choice ◽  
The Other ◽  
Route Guidance ◽  
Older Children ◽  
Aversive Effect ◽  
Architectural Elements ◽  
Route Choices ◽  
Subway Stations ◽  
Dynamic Route

Abstract Guidance to emergency exits play an important role for safe evacuation. Dynamic route guidance by colored flashing lights and strobe lights at emergency exits has been tested [1–3], but the effects of dynamic lights to support route choices need to be determined in more detail. Also, the guidance effects of different colors need to be examined and the reaction of various groups of evacuees. The paper analyzes the effects of red and green running lights on route choice in subway stations comparing adults and older children (10 to 12 years old). Data was gathered in a laboratory experiment, focusing on the concept of affordance [4, 5]. Participants were asked to make a decision about the safest direction between two alternative directions. Their choice was either unsupported or supported by red or green running lights. In general, an interaction between color and direction of the running light was found. Green running lights influenced route choices of both participant groups and led participants clearly into the direction indicated by the lights. Red running lights influenced route choices of both participant groups, but red lights lead to ambiguous decisions. Architectural elements such as stairs influenced route choices of both participant groups (functional affordance). But green running light offered a stronger indication to a safe route (cognitive affordance) than a visible staircase (functional affordance). Green lights even led participants to modify their route preference. In contrast, red running lights had an aversive effect: older children chose against the lights and preferred the other direction than the red lights were directing to. Implications for design of dynamic route guidance are discussed. This includes colored running lights to lead evacuees to a safe exit and to implement the influence of running lights on route choice and movement in simulations.

scholarly journals Effect of ceramic thicknesses and opacities on water sorption and solubility of a light-curing resin cement by different units

2021 ◽  
Vol 20 ◽  
pp. e211656
Author(s):  
Gabriela Alves de Cerqueira ◽  
Lais Sampaio Souza ◽  
Rafael Soares Gomes ◽  
Giselle Maria Marchi ◽  
Paula Mathias
Keyword(s):  
Water Sorption ◽  
Light Emitting Diode ◽  
Lithium Disilicate ◽  
Resin Cement ◽  
The Other ◽  
Experimental Conditions ◽  
Light Emitting ◽  
Light Curing

Aim: This study evaluated the water sorption and solubility of a light-cured resin cement, under four thicknesses and four opacities of a lithium disilicate ceramic, also considering three light-emitting diode (LED) units. Methods: A total of 288 specimens of a resin cement (AllCem Veneer Trans – FGM) were prepared, 96 samples were light-cured by each of the three light curing units (Valo – Ultradent / Radii-Cal – SDI / Bluephase II – Ivoclar Vivadent), divided into 16 experimental conditions, according to the opacities of the ceramic: High Opacity (HO), Medium Opacity (MO), Low Translucency (LT), High Translucency (HT), and thicknesses (0.3, 0.8, 1.5, and 2.0 mm) (n = 6). The specimens were weighed at three different times: Mass M1 (after making the specimens), M2 (after 7 days of storage in water), and M3 (after dissection cycle), for calculating water sorption and solubility. Results: The higher thickness of the ceramic (2.0 mm) significantly increased the values of water sorption (44.0± 4.0) and solubility (7.8±0.6), compared to lower thicknesses. Also, the ceramic of higher opacity (HO) generated the highest values of sorption and solubility when compared to the other opacities, regardless of the thickness tested (ANOVA-3 factors / Tukey’s test, α = 0.05). There was no influence of light curing units. Conclusion: Higher thicknesses and opacities of the ceramic increased the water sorption and solubility of the tested light-cured resin cement.

scholarly journals Monitoring and Search of Coma Patients using Variable Motion Sensor System

2019 ◽  
Vol 8 (9S2) ◽  
pp. 307-310
Keyword(s):  
Visual Perception ◽  
Pulse Rate ◽  
The Other ◽  
Sensor System ◽  
Motion Sensor ◽  
Basic Part ◽  
Movement Recognition

It is vital to consistently screen the oblivious/extreme lethargies patients to comprehend their wellbeing condition. The primary objectives of the proposed is to achieve two things. 1) Monitoring and cautioning the restorative individual is the basic part, when the incapacitated additions cognizance utilizing movement recognition framework. 2) Continuous observing and assessment of basic signs of the patient, for example, Pulse rate and warmth and alarm the specialist at whatever point consideration is required. Wearable Motion sensor framework can be utilized to screen different body developments such and hand development as visual perception flicker development to find the cognizant condition of an individual. This framework will all around likely be exceptionally useful in helping the specialist about the wellbeing state of the other than cognizant patient and cautioning the doctor at whatever point care is required. The proposed framework will help your specialist by providing an alert about the wellbeing state of the patient, when the spot of basic signs reported.

scholarly journals Relations and evolution in Cheilanthes (Sinopteridaceae, Pteridophita) in Macaronesia and Mediterranean area, deduced from genome analysis of their hybrids

1983 ◽  
Vol 8 ◽  
pp. 101-126 ◽  
Author(s):  
G. Vida ◽  
A. Major ◽  
T. Reichstein
Keyword(s):  
Chromosome Number ◽  
Genome Analysis ◽  
Chromosome Doubling ◽  
Diploid Species ◽  
Mediterranean Area ◽  
Basic Chromosome Number ◽  
The Other ◽  
Experimental Conditions ◽  
Natural Group ◽  
Basic Chromosome

Nine species of "Cheilantoid ferns" are known to grow in Macaronesia and the Mediterranean basin. Two of them (lacking a pseudo-indusium and having the basic chromosome number X = 29), both aggregate species which we prefer to retain in Notholaena, are not included in this study. The other seven species (with distinct pseudo-indusium and the basic chromosome number X = 30), which we accept as members of the genus Cheilanthes Sw. sensu stricto, were subjected to detailed genome analysis of their natural and experimentally produced hybrids and shown to represent an aggregate of four very distinct ancestral diploids and three allotetraploids. The latter must have once been formed by chromosome doubling in the three diploid hybrids of C. maderensis Lowe with the other three diploid species. Theoretically three more allotetraploids would be possible but their formation has obviously been prevented by the geographical separation of the three respective diploids. The most widely distributed of the tetraploids, i.e. C. pteridioides (Reich.) C.Chr. has also been resynthesized from its ancestors (still sympatric) under experimental conditions. The intermediate morphology of the allotetraploids (as compared with their diploid ancestors) is obviously the reason why their status and existence has so long escaped recognition in Europe. These seven species form a natural group and, in our opinion, should not be divided into sections.

Effectiveness of Directional Microphones and Noise Reduction Schemes in Hearing Aids: A Systematic Review of the Evidence

2005 ◽  
Vol 16 (07) ◽  
pp. 473-484 ◽  
Author(s):  
Ruth A. Bentler
Keyword(s):  
Systematic Review ◽  
Noise Reduction ◽  
Hearing Aids ◽  
Small Sample Size ◽  
Careful Consideration ◽  
Small Sample ◽  
Experimental Conditions ◽  
Directional Microphones ◽  
Directional Microphone

A systematic review of the literature was undertaken to find evidence of real-world effectiveness of directional microphone and digital noise reduction features in current hearing aids. The evidence was drawn from randomized controlled trials, nonrandomized intervention studies, and descriptive studies. The quality of each study was evaluated for factors such as blinding, power of statistical analyses, and use of psychometrically strong outcome measures. Weaknesses in the identified studies included small sample size, resultant poor power to detect potentially worthwhile differences, and overlapping experimental conditions. Nine studies were identified for directional microphones, and the evidence (albeit weak) supports effectiveness. Two studies were identified for the noise reduction feature, and the evidence was equivocal. For the researcher, such a systematic review should encourage the careful consideration of appropriate methodologies for assessing feature effectiveness. For the clinician, the outcomes reported herein should encourage use of such a systematic review to drive clinical practice.

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