20,596 research outputs found
More adult-born dentate gyrus neurons to weaken cocaine-related retrograde memories: an in vivo strategy employing exogenous lysophosphatidic acid
The post-training enhancement of adult hippocampal neurogenesis (AHN) has been receiving growing interest as a potential method to manipulate retrograde memories. Recent hypothesis suggest that the addition of adult-born dentate granule cells might promotes remodeling of pre-existing hippocampal circuits, which might both clear cocaine-related memories and facilitate the learning of new adaptive information. Here, we study the effect of stimulating AHN in vivo with exogenous lysophosphatidic acid (LPA) on the maintenance of retrograde cocaine-contextual associative memories. Male C57BL/6J mice trained in a cocaine-induced Conditioned Place Preference (CPP) model were later submitted to repeated intracerebroventricular (i.c.v.) injections of LPA, Ki16425 or vehicle solution during withdrawal. Afterwards, the long-term persistence of the cocaine-CPP was assessed and the mediational role of AHN in this process was evaluated. In addition, wild-type and mice lacking the LPA1 receptor received a single i.c.v. injection of LPA, Ki16425 or vehicle to assess the role of the LPA1 receptor in the LPA-induced increase of AHN. Our results revealed that the chronic administration of LPA decreased the retention of a previously acquired cocaine-induced CPP. This effect was mediated by an LPA-induced increase of AHN. In contrast, mice treated with Ki16425 showed reduced cocaine-CPP retention, but they increased their preference for the cocaine-paired compartment throughout CPP extinction. Besides, no effects of Ki16425 on AHN were found. Immunohistochemical studies suggested that LPA stimulated cell proliferation and promoted neuronal maturation with a key role of the LPA1 receptor. These findings emphasize the relevance of LPA and its LPA1 receptor as an in vivo modulator of AHN and the utility of the post-training increase of adult-born hippocampal neurons to weaken cocaine-context associations.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
On Shifting a Nations Collective Memory: The Role of Ahn Jung-geun in South Koreas Foreign Policy
This article revisits the role that Ahn Jung-geun plays in Korean collective memory today and contrasts this with the Moon administrations foreign policy. An analysis of Korean collective memory shows that Ahns assassination of Ito Hirobumi is heavily emphasized but Ahns ultimate goal of bringing peace to Northeast Asia is overlooked. This emphasis is understood through Jan Assmanns model of collective memory. Based on Aleida Assmann and Linda Shortts proposition, it is argued that the historical figure of Ahn can instead play a constructive role. Shifting the focus of collective memory toward Ahns ambition for peace in Northeast Asia may serve as a positive nudge for Seouls Japan policy, thus helping to ameliorate Korea-Japan relations in the medium term
Bier-bearing Inferiors and the Skin of the Community in Modern and Contemporary Village Society: Cases from Southern Gyeonggi Province
In this paper I analyze what bier–bearers did for the village community,
mainly based on the fieldwork interviews carried out in southern Gyeonggi
area. Focused on the bier–shouldering practice, those interviews illuminate the
role of the inferiors (sangnom 常–, hain 下人, and jungin 中人) who resided in
the social border area of the village community. It was their job to perform the
lowly work both in ritual and ordinary practices, so they could not escape from
social disdain. I begin this article by tracing how sachon gye (四寸契), one of the
modern rural organizations for bier–bearing, developed and elucidate its social
and cultural meanings, which were consistently under the influence of the
yangban-commoner relationship. I then extend the analysis to outline a number
of incidents in the southern Gyeonggi area. The final section classifies the
southern Gyeonggi cases into two sociohistorical groups to discuss the social and
cultural meanings of the abolition of the discriminatory bier–shouldering practices
and address debates about immunity and the other community
PCA consistency in high dimension, low sample size context
Principal Component Analysis (PCA) is an important tool of dimension
reduction especially when the dimension (or the number of variables) is very
high. Asymptotic studies where the sample size is fixed, and the dimension
grows [i.e., High Dimension, Low Sample Size (HDLSS)] are becoming increasingly
relevant. We investigate the asymptotic behavior of the Principal Component
(PC) directions. HDLSS asymptotics are used to study consistency, strong
inconsistency and subspace consistency. We show that if the first few
eigenvalues of a population covariance matrix are large enough compared to the
others, then the corresponding estimated PC directions are consistent or
converge to the appropriate subspace (subspace consistency) and most other PC
directions are strongly inconsistent. Broad sets of sufficient conditions for
each of these cases are specified and the main theorem gives a catalogue of
possible combinations. In preparation for these results, we show that the
geometric representation of HDLSS data holds under general conditions, which
includes a -mixing condition and a broad range of sphericity measures of
the covariance matrix.Comment: Published in at http://dx.doi.org/10.1214/09-AOS709 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
A note on constrained degree reduction of polynomials in Bernstein–Bézier form over simplex domain
AbstractIn the paper [H.S. Kim, Y.J. Ahn, Constrained degree reduction of polynomials in Bernstein–Bézier form over simplex domain, J. Comput. Appl. Math. 216 (2008) 14–19], Kim and Ahn proved that the best constrained degree reduction of a polynomial over d-dimensional simplex domain in L2-norm equals the best approximation of weighted Euclidean norm of the Bernstein–Bézier coefficients of the given polynomial. In this paper, we presented a counterexample to show that the approximating polynomial of lower degree to a polynomial is virtually non-existent when d≥2. Furthermore, we provide an assumption to guarantee the existence of solution for the constrained degree reduction
Modality and Hedging Utilization of Rebecca Ahn to Maintain Language Power in the Movie: the Bling Ring
Keywords: Language Power, Modality, Epistemic Modality, Deontic Modality, DynamicModality, Hedging, Propositional Hedging and Speech Act Hedging. This research described the utilization of modality and hedging expressions by Rebecca Ahn to maintain language power in The Bling Ring movie. Modality and hedging are linguistics features which are useful and possibly be utilized when a person may desire to appear firmly aligned to an idea but wish for limiting how much it may be represented in terms of a firm promise and command. Furthermore, modality and hedging were proven as the factors to maintain language power since both modality and hedging can modify a message to appear just like what a speaker wanted. Qualitative approach is applied in order to describe the linguistic phenomenon holistically. The data is taken from The Bling Ring movie script to obtain the utterances of Rebecca Ahn as the language power holder, and the movie is watched to get the context of the utterance. The data analysis is done with the implementation of coding procedure in order to categorize and describe the findings.On the basis of the findings, it can be concluded that Rebecca Ahn maintains language power by utilizing epistemic modality in delivering the value of deduction and a story told; by deontic modality in giving order and promise, and in committing herself and or her friends to do certain action motivated by certain situation; by dynamic modality in showing her desire toward something, by propositional hedging in modifying spoken ideas; and by speech act hedging in modifying an order into a request to hide the force. Although it is mostly believed that power only can be possessed through social status or position, the utilization of certain linguistic features such as modality and hedging can support a power holder like Rebecca Ahn to control her friends to do particular intended action. Thus, Rebecca Ahn does more effort to utilize the power by demonstrating modality and hedging. It means power is possessed through effort. Thus, power is noticed when the Rebecca Ahn's friends perform an action which Rebecca Ahn expects them to do.Finally, the researcher suggests the next researcher to; find a character's motives of language power utilization in order to gain deeper understanding, and; employ modal logic model proposed by Portner (2009) to get more exact analysis to avoid subjective bias. Meanwhile, The Faculty of Cultural Studies of Universitas Brawijaya can consider this topic to be taught in the Discourse Analysis class to give students the knowledge of applied discourse
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