scholarly journals Ratio dependence in small number discrimination is affected by the experimental procedure

2015 ◽  
Vol 6 ◽  
Author(s):  
Christian Agrillo ◽  
Laura Piffer ◽  
Angelo Bisazza ◽  
Brian Butterworth
Keyword(s):  
Experimental Procedure ◽  
Ratio Dependence ◽  
Number Discrimination

Induced Alpha-band Oscillations Reflect Ratio-dependent Number Discrimination in the Infant Brain

2009 ◽  
Vol 21 (12) ◽  
pp. 2398-2406 ◽  
Author(s):  
Melissa E. Libertus ◽  
Laura B. Pruitt ◽  
Marty G. Woldorff ◽  
Elizabeth M. Brannon
Keyword(s):  
Spectral Power ◽  
Brain Activity ◽  
Human Life ◽  
Alpha Band ◽  
Weber’S Law ◽  
Weber's Law ◽  
Ratio Dependence ◽  
Number Discrimination ◽  
Behavioral Studies ◽  
Ratio Dependent

Behavioral studies show that infants are capable of discriminating the number of objects or events in their environment, while also suggesting that number discrimination in infancy may be ratio-dependent. However, due to limitations of the dependent measures used with infant behavioral studies, the evidence for ratio dependence falls short of the vast psychophysical datasets that have established ratio dependence, and thus, adherence to Weber's Law in adults and nonhuman animals. We addressed this issue in two experiments that presented 7-month-old infants with familiar and novel numerosities while electroencephalogram measures of their brain activity were recorded. These data provide convergent evidence that the brains of 7-month-old infants detected numerical novelty. Alpha-band and theta-band oscillations both differed for novel and familiar numerical values. Most importantly, spectral power in the alpha band over midline and right posterior scalp sites was modulated by the ratio between the familiar and novel numerosities. Our findings provide neural evidence that numerical discrimination in infancy is ratio dependent and follows Weber's Law, thus indicating continuity of these cognitive processes over development. Results are also consistent with the idea that networks in the frontal and parietal cortices support ratio-dependent number discrimination in the first year of human life, consistent with what has been reported in neuroimaging studies in adults and older children.

On the Difference Between Monkeys' and Humans' Response Times: Could It Be the Experimental Procedure?

2012 ◽  
Author(s):  
Guy E. Hawkins ◽  
Birte U. Forstmann ◽  
Eric-Jan Wagenmakers ◽  
Scott D. Brown
Keyword(s):  
Response Times ◽  
Experimental Procedure ◽  
The Difference

The Cultivation of Gratitude: An Online Experimental Procedure

2006 ◽  
Author(s):  
Mayra L. Torres ◽  
Nancy J. Cobb ◽  
Ramani S. Durvasula
Keyword(s):  
Experimental Procedure

Relationship between Faithfulness and Preference of Stars in a Planetarium

2019 ◽  
Vol 2 (1) ◽  
pp. 10402-1-10402-11
Author(s):  
Midori Tanaka ◽  
Takahiko Horiuchi ◽  
Ken’ichi Otani
Keyword(s):  
Light Source ◽  
Preference Rating ◽  
Experimental Procedure ◽  
Male And Female ◽  
Astronomical Observations ◽  
Low Luminance ◽  
Projection Pattern ◽  
The Relationship ◽  
Star Field

Abstract A planetarium imitates a starry sky with physical and technical limitations using a dome, projector, and light source. It is widely used for entertainment, and astronomy and physics educations. In our previous study, we investigated the evaluation for faithful reproduction of a star field in a planetarium by performing psychometric experiments with 20 observers for plural projection patterns with different reproduction factors (color, luminance, and size of projected stars). In this study, we investigate the relationship between faithfulness and preference of a star field in a planetarium through a psychometric experiment with 47 observers. The experimental procedure followed the previous study. The rating of faithfulness improved for the projection pattern with a smaller star size. For the preference evaluation, the projection pattern with low luminance significantly lowered the preference rating. The results of the experiment indicate that the preferable star reproduction was different between male and female observers, whereas the faithful star reproduction was not significantly different in the evaluations between male and female observers. The male observers sought a faithful star reproduction as the preferred reproduction. In contrast, the female observers did not feel the faithful star reproduction preferable, and evaluated the more brilliant star reproduction as the preferred reproduction. These results were not dependent on the experience in astronomical observations.

Role of Artesunate in Potentiation of β-lactam Against Methicillin Resistant Staphylococcus aureus (MRSA) Isolated from Bovine Mastitis and its Histopathology Impact In-Vivo Study

2020 ◽  
Keyword(s):  
Clavulanic Acid ◽  
Resistance Mechanism ◽  
Bovine Mastitis ◽  
Lethal Challenge ◽  
Experimental Procedure ◽  
Appropriate Treatment ◽  
Amoxicillin Clavulanic Acid ◽  
Mrsa Infection

This article discusses the augmenting influence of Artesunate (ART) in combination with β-lactams (amoxicillin/clavulanic acid) antibiotic in sepsis mice models infected by a lethal challenge dose of live coagulase positive enterotoxigenic (Sec) MRSA that was isolated from a case of chronic bovine mastitis. The main goal is to find an appropriate treatment to overcome resistance mechanism of MRSA towards β-lactams antibiotic. Fifty healthy adult Swiss mice divided into 5 equal groups were used in the experimental procedure. The infected group that treated with both ART and β-lactams (amoxicillin/clavulanic acid) antibiotic revealed complete inhibition of MRSA count with complete normal macroscopic and histopathological features. We suggest that ART can potentiate the antibacterial action of β-lactams (amoxicillin/Clavulanic) acid against MRSA infection. The combination of ART and antibiotic can overcome MRSA resistance mechanism and so could be considered a novel candidate to overcome mastitis and/or sepsis caused by MRSA.

Methods for determining the settling velocity profiles of solids in storm sewage

1996 ◽  
Vol 33 (9) ◽  
pp. 117-125 ◽  
Author(s):  
Emmanuelle Aiguier ◽  
Ghassan Chebbo ◽  
Jean-Luc Bertrand-Krajewski ◽  
Peter Hedges ◽  
Naomi Tyack
Keyword(s):  
Suspended Solids ◽  
Settling Velocity ◽  
Test Procedure ◽  
Velocity Profiles ◽  
Test Methods ◽  
Efficient Treatment ◽  
Experimental Procedure ◽  
Comparative Tests ◽  
Settling Process ◽  
Settling Characteristics

Recently, research has shown that a settling process is an efficient treatment for the removal of suspended solids from storm sewage. In order to design settling tanks, there is a need to determine the settling velocity characteristics of these solids. Devices and test methods for measuring settling velocities of solids in storm sewage have been developed by researchers. A literature review has revealed that the settling velocity profiles obtained with some methods (Chebbo, 1992), (Michelbach and Wohrle, 1993) and (Tyack et al., 1993) are very different. In order to explain why the results are different and to quantify the influence of the experimental procedure on the settling velocity grading curves, we have compared the selected methods when tested with the same sample and we have studied the effects of the conservation of the sample before the test, of the concentration of solids in the device and of the nature of the water on the settling velocity profiles. The results of the comparative tests indicate that the settling velocities are significantly lower with both the Cergrene and Aston methods than with the UFT test procedure. Moreover, the study has shown that the settling characteristics of solids change with time, that the use of sewage liquor rather than demineralised water or drinking water can change the results of the measurement and that the higher the concentration of solids, the greater the velocity of settled particles.

A Refined Framework for Precision and Translational Proteomics in Clinical Research

2020 ◽  
Vol 17 ◽  
Author(s):  
Min Wang ◽  
Daozhen Chen ◽  
Yankai Xia ◽  
Tao Zhou ◽  
Shi-Wen Jiang
Keyword(s):  
Data Interpretation ◽  
Clinical Proteomics ◽  
Experimental Procedure ◽  
Clinical Biomarkers ◽  
Experimental Variation ◽  
Tier System ◽  
Initial Discovery ◽  
Translational Studies ◽  
Potential Biomarkers

: Most clinical related proteomic studies were aimed to screen potential biomarkers for clinical usage. However, it is known that only a few candidates could be validated in later stages. Besides clinical biomarkers, it also necessary to identify key proteins to better understand the molecular mechanism of human diseases. Here, we updated the connotations of precision and translational proteomics and proposed a refined research framework for clinical proteomics. We abstracted the framework as a three-tier system: to determine research objective and approach for achieving a certain purpose, to choose the appropriate methods for optimal results, and to apply standardized experimental procedure for reliable and reproducible results. Started from the initial discovery stage, we divided the following proteomics-driven translational studies into two directions: biomarker screening and mechanism investigation. We also discussed possible causes that may lead to high rates of experimental variation and low rates of follow-up validation. Moreover, we pointed out that the main bottlenecks for the identification of effective targets are data interpretation and statistical inference. Finally, we emphasized that the transparency of experimental design and results can help to ensure data quality. Conclusively, the refined framework provides constructive recommendations and comprehensive guides for designing and performing clinical related proteomic studies with the aim of obtaining reliable and reproducible results. It can also help to further promote the standardization and integration of proteomic studies.

Full Kinetics and a Mechanism Investigation for the Generation of 4- Substituted 1, 4-Dihydropyridine Derivatives in the Presence of Green Catalyst and Aqueous Medium: Experimental Procedure

2020 ◽  
Vol 17 ◽  
Author(s):  
Sayyed Mostafa Habibi-Khorassani ◽  
Mehdi Shahraki ◽  
Sadegh Talaiefar
Keyword(s):  
Reaction Mechanism ◽  
Reaction Centre ◽  
Green Catalyst ◽  
Experimental Procedure ◽  
Dominant Mechanism ◽  
Rate Determining Step ◽  
12 Steps ◽  
Reaction Constant ◽  
Substituted 1 ◽  
Dihydropyridine Derivatives

Aims and Objective: The main objective of the kinetic investigation of the reaction among ethyl acetoacetate 1, ammoniumacetat 2, dimedone 3 and diverse substitutions of benzaldehyde 4-X, (X= H, NO2, CN, CF3, Cl, CH (CH3)2, CH3, OCH3, OCH3, and OH) for the generation of 4-substituted 1, 4-dihydropyridine derivatives (product 5) was the recognition of the most realistic reaction mechanism. The layout of the reaction mechanism studied kinetically by means of the UV-visible spectrophotometry approach. Materials and Methods: Among the various mechanisms, only mechanism1 (path1) involving 12 steps was recognized as a dominant mechanism (path1). Herein, the reaction between reactants 1 and 2 (kobs= 814.04 M-1 .min-1 ) and also compound 3 and 4-H (kobs= 151.18 M-1 .min-1 ) were the logical possibilities for the first and second fast steps (step1 and step2, respectively). Amongst the remaining steps, only step9 of the dominant mechanism (path1) had substituent groups (X) near the reaction centre that could be directly resonated with it. Results and Discussion: Para electron-withdrawing or donating groups on the compound 4-X increases the rate of the reaction 4 times more or decreases 8.7 times less than the benzaldehyde alone. So, this step is sensitive for monitoring any small or huge changes in the reaction rate. For this reason, step9 is the rate-determining step of the reaction mechanism (path1). Conclusion: The recent result is the agreement with the Hammett description with an excellent dual substituent factor (r = 0.990) and positive value of reaction constant (ρ = +0.9502) which confirmed both the resonance and inductive effects “altogether” contributed on the reaction centre of step9 in the dominant mechanism (path1).

Sign in / Sign up

Export Citation Format

Share Document