Border Elements Deter Shape-From-Shadow Via Negative Polarity, Not Motion, Not Color

2004 ◽  
Author(s):  
John M. Kennedy ◽  
Juan Bai
2002 ◽  
Vol 16 (2) ◽  
pp. 114-118 ◽  
Author(s):  
Timo Ruusuvirta ◽  
Heikki Hämäläinen

Abstract Human event-related potentials (ERPs) to a tone continuously alternating between its two spatial loci of origin (middle-standards, left-standards), to repetitions of left-standards (oddball-deviants), and to the tones originally representing these repetitions presented alone (alone-deviants) were recorded in free-field conditions. During the recordings (Fz, Cz, Pz, M1, and M2 referenced to nose), the subjects watched a silent movie. Oddball-deviants elicited a spatially diffuse two-peaked deflection of positive polarity. It differed from a deflection elicited by left-standards and commenced earlier than a prominent deflection of negative polarity (N1) elicited by alone-deviants. The results are discussed in the context of the mismatch negativity (MMN) and previous findings of dissociation between spatial and non-spatial information in auditory working memory.


2020 ◽  
Author(s):  
Sarah Delanys ◽  
Farah Benamara ◽  
Véronique Moriceau ◽  
François Olivier ◽  
Josiane Mothe

BACKGROUND With the advent of digital technology and specifically user generated contents in social media, new ways emerged for studying possible stigma of people in relation with mental health. Several pieces of work studied the discourse conveyed about psychiatric pathologies on Twitter considering mostly tweets in English and a limited number of psychiatric disorders terms. This paper proposes the first study to analyze the use of a wide range of psychiatric terms in tweets in French. OBJECTIVE Our aim is to study how generic, nosographic and therapeutic psychiatric terms are used on Twitter in French. More specifically, our study has three complementary goals: (1) to analyze the types of psychiatric word use namely medical, misuse, irrelevant, (2) to analyze the polarity conveyed in the tweets that use these terms (positive/negative/neural), and (3) to compare the frequency of these terms to those observed in related work (mainly in English ). METHODS Our study has been conducted on a corpus of tweets in French posted between 01/01/2016 to 12/31/2018 and collected using dedicated keywords. The corpus has been manually annotated by clinical psychiatrists following a multilayer annotation scheme that includes the type of word use and the opinion orientation of the tweet. Two analysis have been performed. First a qualitative analysis to measure the reliability of the produced manual annotation, then a quantitative analysis considering mainly term frequency in each layer and exploring the interactions between them. RESULTS One of the first result is a resource as an annotated dataset . The initial dataset is composed of 22,579 tweets in French containing at least one of the selected psychiatric terms. From this set, experts in psychiatry randomly annotated 3,040 tweets that corresponds to the resource resulting from our work. The second result is the analysis of the annotations; it shows that terms are misused in 45.3% of the tweets and that their associated polarity is negative in 86.2% of the cases. When considering the three types of term use, 59.5% of the tweets are associated to a negative polarity. Misused terms related to psychotic disorders (55.5%) are more frequent to those related to mood disorders (26.5%). CONCLUSIONS Some psychiatric terms are misused in the corpora we studied; which is consistent with the results reported in related work in other languages. Thanks to the great diversity of studied terms, this work highlighted a disparity in the representations and ways of using psychiatric terms. Moreover, our study is important to help psychiatrists to be aware of the term use in new communication media such as social networks which are widely used. This study has the huge advantage to be reproducible thanks to the framework and guidelines we produced; so that the study could be renewed in order to analyze the evolution of term usage. While the newly build dataset is a valuable resource for other analytical studies, it could also serve to train machine learning algorithms to automatically identify stigma in social media.


Author(s):  
Martin Haspelmath

This chapter examines formal and functional types of indefinite pronoun. It first presents some examples of different indefinite pronoun series in a variety of languages, focusing on a formal element shared by all members of an indefinite pronoun series, such as some and any in English. This element is called indefiniteness marker, an affix or a particle which stands next to the pronoun stem. The chapter proceeds by discussing two main types of derivational bases from which indefinite pronouns are derived in the world's languages: interrogative pronouns and generic ontological category nouns like person, thing or place. It also looks at the main functional types of indefinite pronoun, namely: negative indefinite pronouns and negative polarity (or scale reversal). Finally, it analyses some alternatives to indefinite pronouns, including generic nouns, existential sentences, non-specific free relative clauses, and universal quantifiers.


2010 ◽  
Vol 28 (4) ◽  
pp. 931-952 ◽  
Author(s):  
Jan-Philipp Soehn ◽  
Beata Trawiński ◽  
Timm Lichte

2003 ◽  
Vol 34 (3) ◽  
pp. 516-526 ◽  
Author(s):  
Yuji Takano

Since the emergence of Kayne's (1994) stimulating proposal for an antisymmetric theory of phrase structure and linear order, much work has been devoted to arguing for or against his theory as well as discussing its empirical predictions. As a result, for a number of phenomena involving rightward positioning, such as rightward adjuncts, heavy NP shift, extraposition, postverbal subjects, and postverbal constituents in OV languages, there now exist both an approach consistent with Kayne's theory (the antisymmetric approach) and another not consistent with it (the symmetric approach). In such a situation, it is often difficult to show on empirical grounds that one approach is superior to the other (see Rochemont and Culicover 1997). In what follows, I describe this situation with respect to two well-known phenomena in English: rightward positioning of adjuncts and heavy NP shift. For each of these phenomena, the symmetric and antisymmetric approaches have been proposed, and both approaches can correctly account for the data discussed in previous studies. Here, I examine the approaches from a novel point of view, showing that data involving the licensing of negative polarity items allow us to differentiate them and to decide which is the right one for each of the two empirical domains. Interestingly, the relevant facts lead to different conclusions for the two phenomena. The results have important implications for the antisymmetric view of syntax.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Debdatta Debnath ◽  
Anup Bandyopadhyay

Abstract At the acoustic speed, we have investigated the existence of ion-acoustic solitary structures including double layers and supersolitons in a collisionless magnetized plasma consisting of negatively charged static dust grains, adiabatic warm ions, and nonthermal electrons. At the acoustic speed, for negative polarity, the system supports solitons, double layers, supersoliton structures after the formation of double layer, supersoliton structures without the formation of double layer, solitons after the formation of double layer whereas the system supports solitons and supersolitons without the formation of double layer for the case of positive polarity. But it is not possible to get the coexistence of solitary structures (including double layers and supersolitons) of opposite polarities. For negative polarity, we have observed an important transformation viz., soliton before the formation of double layer → double layer → supersoliton → soliton after the formation of double layer whereas for both positive and negative polarities, we have observed the transformation from solitons to supersolitons without the formation of double layer. There does not exist any negative (positive) potential solitary structures within 0 < μ < μ c (μ c < μ < 1) and the amplitude of the positive (negative) potential solitary structure decreases for increasing (decreasing) μ and the solitary structures of both polarities collapse at μ = μ c, where μ c is a critical value of μ, the ratio of the unperturbed number density of electrons to that of ions. Similarly there exists a critical value β e2 of the nonthermal parameter β e such that the solitons of both polarities collapse at β e = β e2.


2021 ◽  
Author(s):  
Johan Fourdrinoy ◽  
Julien Dambrine ◽  
Madalina Petcu ◽  
Morgan Pierre ◽  
Germain Rousseaux

&lt;p&gt;While seeking to revisit an old experiment of John Scott Russell, we discovered a new mechanism for generating a non-shoaling bolus (an ovoid coherent mass of recirculating mixed fluids immerged in a surrounding medium/a of different density/ies) propagating along a pycnocline. In a study about dead-water (Fourdrinoy et al. 2020), a wave resistance phenomenon induced by internal waves formation at the interface between waters of different densities, we modified the setup used by Scott Russell. The Scottish engineer studied the formation and propagation of dispersive waves when an object is removed from a laterally confined open channel with a shallow layer of water. The &amp;#8220;vacuum&amp;#8221; created by the mass removal generates a linear dispersive free surface deformation with a front of negative polarity followed by a wave train. If we extend this configuration to a two-layers stratification, we can observe a linear dispersive wave with negative polarity &amp;#224; la Scott Russell, propagating along the interface. In addition, the removal of the object generates under certain conditions a bolus which induces a mixing zone and a gradient transition layer. We will present this new method of boluses creation, as well as an experimental characterization with space-time diagrams thanks to a subpixel detection procedure.&lt;/p&gt;&lt;p&gt;The dual nature of the dead-water phenomenology: Nansen versus Ekman wave-making drags.&lt;br&gt;Johan Fourdrinoy, Julien Dambrine, Madalina Petcu, Morgan Pierre and Germain Rousseaux.&lt;br&gt;Proceedings of the National Academy of Sciences, Volume 117, Issue 29, p. 16739-16742, July 2020.&lt;/p&gt;


2018 ◽  
Author(s):  
M. H. Hooi ◽  
W. K. Tiong ◽  
K. G. Tay ◽  
S. N. Sze ◽  
K. L. Chiew

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