Testing the Hypothesis of Labelled Detectors

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 113-113 ◽  
Author(s):  
A I Cogan
Keyword(s):  
The Body ◽  
Relative Depth ◽  
Weak Version ◽  
Strong Version ◽  
Specific Mechanism ◽  
Detection And Identification ◽  
Uncrossed Disparity ◽  
Complex Shapes ◽  
Neural Substrate ◽  
Additional Processing

The hypothesis of labelled detectors (or ‘lines’) is the present-day version of the basic Müller - Helmholtz doctrine. Müller's dictum of specific energy of nerves stated: “the same internal cause excites (…) in each sense the sensation peculiar to it”. Helmholtz made ‘the cause’ external to the body and postulated that all knowledge about the world thus comes through the senses. The key word is specificity. The strong version of the hypothesis must treat detection - identification as a single task: a stimulus would be identified whenever it is detected. The weak version requires only that we identify a specific mechanism by which both detection and identification are achieved, even though the latter may require additional processing. In the general case, the strong version (with its ludicrous ‘grandmother cell’ as the neural substrate) finds little support. Detection and recognition of complex shapes (letters, faces, etc) aside, even discrimination between simple increments and decrements of luminance is difficult to attribute directly to a specific mechanism (in this case, the activity in either ON or OFF systems, respectively). This is demonstrated by experiment 1 reported here. However, perception of relative depth seems to conform to the strong version of the hypothesis, as experiment 2, also reported here, indicates. Thus, at least some specific neural mechanisms (in this case, probably the crossed and uncrossed disparity detectors) may be indeed linked directly to perception.

scholarly journals Is preregistration worthwhile?

2019 ◽  
Author(s):  
Aba Szollosi ◽  
David Kellen ◽  
Danielle Navarro ◽  
Rich Shiffrin ◽  
Iris van Rooij ◽  
...  
Keyword(s):  
Statistical Models ◽  
Statistical Tests ◽  
Error Rates ◽  
Statistical Techniques ◽  
Weak Version ◽  
Strong Version ◽  
Statistical Problems

Proponents of preregistration argue that, among other benefits, it improves the diagnosticity of statistical tests [1]. In the strong version of this argument, preregistration does this by solving statistical problems, such as family-wise error rates. In the weak version, it nudges people to think more deeply about their theories, methods, and analyses. We argue against both: the diagnosticity of statistical tests depend entirely on how well statistical models map onto underlying theories, and so improving statistical techniques does little to improve theories when the mapping is weak. There is also little reason to expect that preregistration will spontaneously help researchers to develop better theories (and, hence, better methods and analyses).

scholarly journals Considerations for Goldbach's Strong Conjecture

2021 ◽  
Author(s):  
Carleilton Severino Silva
Keyword(s):  
Number Theory ◽  
Prime Numbers ◽  
Weak Version ◽  
Strong Version ◽  
Leonhard Euler

Since 1742, the year in which the Prussian Christian Goldbach wrote a letter to Leonhard Euler with his Conjecture in the weak version, mathematicians have been working on the problem. The tools in number theory become the most sophisticated thanks to the resolution solutions. Euler himself said he was unable to prove it. The weak guess in the modern version states the following: any odd number greater than 5 can be written as the sum of 3 primes. In response to Goldbach's letter, Euler reminded him of a conversation in which he proposed what is now known as Goldbach's strong conjecture: any even number greater than 2 can be written as a sum of 2 prime numbers. The most interesting result came in 2013, with proof of weak version by the Peruvian Mathematician Harald Helfgott, however the strong version remained without a definitive proof. The weak version can be demonstrated without major difficulties and will not be described in this article, as it becomes a corollary of the strong version. Despite the enormous intellectual baggage that great mathematicians have had over the centuries, the Conjecture in question has not been validated or refuted until today.

scholarly journals Skeptical Theism and the Threshold Problem

1970 ◽  
Vol 18 (1) ◽  
pp. 73-92
Author(s):  
Yishai A. Cohen
Keyword(s):  
Weak Version ◽  
Strong Version ◽  
Skeptical Theism ◽  
Cognitive Faculties ◽  
Threshold Problem

In this paper I articulate and defend a new anti-theodicy challenge to Skeptical Theism. More specifically, I defend the Threshold Problem according to which there is a threshold to the kinds of evils that are in principle justifiable for God to permit, and certain instances of evil are beyond that threshold. I further argue that Skeptical Theism does not have the resources to adequately rebut the Threshold Problem. I argue for this claim by drawing a distinction between a weak and strong version of Skeptical Theism, such that the strong version must be defended in order to rebut the Threshold Problem. However, the skeptical theist’s appeal to our limited cognitive faculties only supports the weak version.

scholarly journals Resource partitioning and ecomorphological variation in two syntopic species of Lebiasinidae (Characiformes) in an Amazonian stream

2016 ◽  
Vol 46 (1) ◽  
pp. 25-36 ◽  
Author(s):  
Nathália Carina dos Santos SILVA ◽  
Aluízio José Lopes da COSTA ◽  
José LOUVISE ◽  
Bruno Eleres SOARES ◽  
Vanessa Cristine e Souza REIS ◽  
...  
Keyword(s):  
Resource Partitioning ◽  
Trophic Ecology ◽  
Species Coexistence ◽  
Stomach Contents ◽  
Relative Length ◽  
Niche Overlap ◽  
The Body ◽  
Feeding Strategies ◽  
Relative Depth ◽  
Feeding Niche

ABSTRACTResource partitioning is important for species coexistence. Species with similar ecomorphology are potential competitors, especially when phylogenetically close, due to niche conservatism. The aim of this study was to investigate the resource partitioning among populations of two species of lebiasinids (Copella nigrofasciata and Pyrrhulina aff. brevis) that co-occur in a first-order Amazonian stream, analyzing the trophic ecology, feeding strategies and ecomorphological attributes related to the use of food and space by these species. Fish were captured in May and September 2010. The stomach contents of 60 individuals were analyzed and quantified volumetrically to characterize the feeding ecology of both species. Eleven morphological attributes were measured in 20 specimens and combined in nine ecomorphological indices. Both species had an omnivorous-invertivorous diet and consumed predominantly allochthonous items. Both showed a tendency to a generalist diet, but intrapopulational variation in resource use was also detected. Overall feeding niche overlap was high, but differed between seasons: low during the rainy season and high in the dry season. In the latter, the food niche overlap was asymmetric because C. nigrofasciata consumed several prey of P. aff. brevis, which reduced its food spectrum. The ecomorphological analysis suggests that C. nigrofasciatahas greater swimming capacity (greater relative length of caudal peduncle) than P. aff. brevis, which has greater maneuverability and tendency to inhabit lentic environments (greater relative depth of the body). Our results demonstrate that these species have similar trophic ecology and suggest a spatial segregation, given by morphological differences related to locomotion and occupation of habitat, favoring their coexistence.

scholarly journals An Experimental and Numerical Comparison of Flow Hydraulic Parameters in Circular Crested Weir Using Flow3D

2016 ◽  
Vol 2 (1) ◽  
pp. 23-37 ◽  
Author(s):  
Farhad Ghazizadeh ◽  
M. Azhdary Moghaddam
Keyword(s):  
Water Discharge ◽  
Geometry Optimization ◽  
The Body ◽  
Numerical Comparison ◽  
Relative Depth ◽  
Flow Depth ◽  
Upstream Slope ◽  
Downstream Slope ◽  
Cfd Method ◽  
Distribution Energy

Circular crested weirs consist of a circular crested of upstream and downstream walls. These weirs are widely used in hydraulic engineering as water discharge structures and can be used to control water level in channels and tanks. In the present study, using Flow3D software, hydraulic properties were investigated to find weir geometry optimization through CFD method. Also, this study attempted to investigate flow on some sections of circular crested weirs in 3 groups and 11 models. Upstream and downstream slope changes as well as the height of the weir were also studied. To validate the model, laboratory models were used. In the research, flow depth parameters on crest, pressure distribution, velocity distribution, energy loss on circular crested weirs, as well as the height and changes of upstream and downstream slope were evaluated. Flow depth on the body of circular crest in this state is about 0.71 (H1). Upstream slope changes on flow depth on the weir’s crest revealed that increasing upstream slope causes to the increase of flow relative depth (H1/R) on the crest about 62%. Downstream changes in H1/R values less than 0.7 have no significant effect on discharge coefficient; however, increasing H1/R values seems to cause more change in slope.

FTIR microspectroscopy coupled with variable selection methods for the identification of flunitrazepam in necrophagous flies

2016 ◽  
Vol 8 (5) ◽  
pp. 968-972 ◽  
Author(s):  
Tainá C. Baia ◽  
Renata A. Gama ◽  
Leomir Aires Silva de Lima ◽  
Kássio M. G. Lima
Keyword(s):  
Variable Selection ◽  
Low Cost ◽  
The Body ◽  
Spectroscopic Techniques ◽  
Selection Methods ◽  
Ftir Microspectroscopy ◽  
Detection And Identification ◽  
Fly Larvae

The detection and identification of a drug in a corpse through the analysis of fly larvae feeding on the body by spectroscopic techniques promises to be of great value, because of their sensitivity, promptness, low cost and simplicity.

The Strong Version of Underdetermination of Theories by Empirical Data.

2008 ◽  
Vol 13 (1) ◽  
pp. 111-117
Author(s):  
Mostafa Taqavi ◽  
Mohammad Zarepour
Keyword(s):  
Empirical Data ◽  
Weak Version ◽  
Strong Version

The Polish researcher in the field of logic and philosophy, Jan Woleński, in one of his recent articles, “Metalogical Observations About the Underdetermination of Theories by Empirical Data,” logically formalized two weak and strong versions of the underdetermination of theories by empirical data (or UT by abbreviation) and with these formalization has metalogically analyzed these two versions. Finally he has deducted that the weak version is defensible while the strong version is not. In this paper we will critically study Woleński's analysis of the strong version of UT.

Crash Behaviour of Various Modern Steels Exposed to High Deformation Rates

2007 ◽  
Vol 344 ◽  
pp. 151-158 ◽  
Author(s):  
Till Laumann ◽  
Markus Pfestorf ◽  
Andreas Beil ◽  
Manfred Geiger ◽  
Marion Merklein
Keyword(s):  
Test Bench ◽  
Microscopic Analysis ◽  
High Strength ◽  
The Body ◽  
Absorbed Energy ◽  
Maximum Deformation ◽  
High Deformation ◽  
Complex Shapes ◽  
Body In White ◽  
Crash Behaviour

The increasing call for significant safety improvements of new cars requires, among other important relevant aspects, the application of high strength materials for the body in white. Quenchable manganese boron alloyed steels like 22MnB5 offer superior strength values, complex shapes and enhanced accuracy. For the evaluation of the crash appropriateness specimens in different annealed states are deformed in a so called drop test bench and hereupon judged in terms of absorbed energy, maximum deformation and other aspects like wrinkling behaviour. Microscopic analysis complements the evaluation of crash-appropriateness.

scholarly journals Examining the Continuity between Life and Mind: Is There a Continuity between Autopoietic Intentionality and Representationality?

Philosophies ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 18
Author(s):  
Wanja Wiese ◽  
Karl J. Friston
Keyword(s):  
Free Energy ◽  
Living System ◽  
Living Systems ◽  
Weak Version ◽  
Strong Version ◽  
Strong Continuity ◽  
Energy Principle ◽  
Free Energy Principle ◽  
Continuity Thesis ◽  
As If

A weak version of life-mind continuity thesis entails that every living system also has a basic mind (with a non-representational form of intentionality). The strong version entails that the same concepts that are sufficient to explain basic minds (with non-representational states) are also central to understanding non-basic minds (with representational states). We argue that recent work on the free energy principle supports the following claims with respect to the life-mind continuity thesis: (i) there is a strong continuity between life and mind; (ii) all living systems can be described as if they had representational states; (iii) the ’as-if representationality’ entailed by the free energy principle is central to understanding both basic forms of intentionality and intentionality in non-basic minds. In addition to this, we argue that the free energy principle also renders realism about computation and representation compatible with a strong life-mind continuity thesis (although the free energy principle does not entail computational and representational realism). In particular, we show how representationality proper can be grounded in ’as-if representationality’.

scholarly journals Active Cell Divisions Generate Exotic Fourfold Orientationally Ordered Phase in Living Tissue

2021 ◽  
Author(s):  
Dillon J Cislo ◽  
Haodong Qin ◽  
Fengshuo Yang ◽  
Mark J Bowick ◽  
Sebastian J Streichan
Keyword(s):  
Cell Proliferation ◽  
Orientational Order ◽  
Subsequent Development ◽  
The Body ◽  
Equilibrium System ◽  
Physical Processes ◽  
Global Order ◽  
Cell Divisions ◽  
Complex Shapes ◽  
Extensive Growth

Morphogenesis, the process through which genes generate form, establishes tissue scale order as a template for constructing the complex shapes of the body plan. The extensive growth required to build these ordered substrates is fuelled by cell proliferation, which, naively, should destroy order. The active mechanisms that couple cellular and physical processes to generate and maintain global order, thereby reconciling this seeming contradiction, remain elusive. Using live imaging and tissue cartography, we quantitatively analyze the dynamics of fourfold tissue ordering in the crustacean Parhyale hawaiensis. We show that cell divisions are the main drivers of tissue flow leading to a fourfold orientationally ordered phase. Waves of anisotropic cell proliferation propagate across the embryo with precise choreography, such that defects introduced into the nascent lattice by cell divisions are healed by subsequent divisions through active defect climb. Orchestrating cell proliferation rates and orientations enables cell divisions to organize, rather than fluidize, the tissue. The result is a robust, active mechanism for generating global orientational order in a non-equilibrium system that sets the stage for the subsequent development of shape and form.

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