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Novelty triggers time-dependent theta oscillatory dynamics in cortical-hippocampal-midbrain circuitry
No full textRapid adaptation to novel environments is crucial for survival, and this ability is impaired in many neuropsychiatric disorders. Understanding neural adaptation to novelty exposure therefore has therapeutic implications. Here, I found that novelty induces time-dependent theta (4-12Hz) oscillatory dynamics in brain circuits including the medial prefrontal cortex (mPFC), ventral hippocampus (vHPC), and ventral tegmental area (VTA), but not dorsal hippocampus (dHPC), as mice adapt to a novel environment. Local field potential (LFP) recordings were performed while mice were freely behaving in a novel or a familiar arena for 10 min. Initially, mice exhibited increased exploratory behavior upon exposure to novelty, which gradually decreased to levels observed in mice exposed to the familiar arena. Over the same time course, the mPFC, vHPC, and VTA displayed progressively increasing theta power through novelty exposure. Additionally, theta coherence and theta phase synchrony measures demonstrated that novelty weakened the connectivity between these areas, which then gradually strengthened to the level observed in the familiar group. Conversely, mice exposed to the familiar arena showed steady and consistent behavior as well as theta dynamics in all areas. Treatment with a dopamine D1-receptor (D1R) antagonist in the vHPC disrupted neurophysiological adaptation to novelty specifically in the vHPC-mPFC and vHPC-VTA circuits, without affecting behavior. Thus, novelty induces distinct theta dynamics that are not readily dictated by behavior in the mPFC, vHPC, and VTA circuits, a process mediated by D1Rs in the vHPC. The observed time-dependent circuit dynamics in the key learning and memory circuit would provide new insights for treating neuropsychiatric disorders that often show impaired novelty processing.Y
On Building a Road Network of North Korea for Transportation Analysis
No full text1990년대 이후 북한의 도로교통이 급성장하고 있다. 남북한 통합 교통망 연구의 중요성에도 불구하고, 교통분석용 북한 도로 네트워크의 미비로 인해 충분한 연구가 진행되지 못하는 실정이다. 본 연구에서는 북한의 도로교통 분석을 위한 기초 자료로서, 고속도로, 1급 도로, 2급 도로로 구성된 간선도로 네트워크 구축 과정을 설명한다. 교통분석용 북한 도로 네트워크 구축 과정은 크게 GIS DB 구축과 교통분석용 네트워크 구축으로 구분되며, 각 과정에서 네 가지 쟁점이 도출되었다. 본 연구는 기준 자료로 선정된 공간정보와 속성정보를 바탕으로 위성영상 자료를 함께 활용하여 각각의 쟁점을 해결하였다. 마지막 결론에서는 본 연구의 성과를 정리하고 향후 연구 방향을 제시한다.N
Radiative cooling technology with artificial intelligence
No full textAs sustainable thermal management becomes a global priority, the development of radiative cooling (RC) technology has recently emerged as a promising solution. Simultaneously, recent advent of artificial intelligence (AI) offers the potential to revolutionize current research in sustainable cooling strategies. This article discusses the advancement of radiative cooling technology through the integration of AI, tackling the challenging issues arising from the conventional approach and offering strategic solutions to address global issues. AI, capable of mimicking or exceeding human capabilities through various algorithms, enables the efficient optimization of RC structures. Moreover, integrating AI with advanced RC technologies, which have the potential to surpass traditional RC configurations and applications but are still in the early stages, can further accelerate progress in the field of RC. Hence, AI-driven RC technologies will contribute to addressing the increasingly prevalent environmental challenges, further being a leading solution for next-generation sustainable thermal managements as these technologies continue to mature.Y
Historiography Overcoming Division - Kang Man-gil's work on the National Unification Front movement
No full text"분단시대의 역사인식"(1978) 이후 강만길 역사학의 과제는 분단극복 사론의 수립이었다. 그 내용은 첫째, 식민지 시대 민족해방운동은 좌우 노선으로 분립되어 있는 것만이 아니라 하나의 통일전선을 형성하기 위한 과정이었음을 밝히고, 둘째, 해방 후의 민족국가 건설 문제를 포함해서 통일 민족국가 수립 운동으로서 민족해방 운동사를 서술하는 것이었다. 강만길은 1991년에 "조선민족혁명당과 통일전선"을 펴냈다. 1980년대 민족 통일전선 운동 연구의 집대성이었다. 이 책은 민족혁명당을 사실상의 좌우합작 통일전선이자, 일본 제국주의 중국 본토 침략을 내다본 민족해방운동 전선이 세계 반파쇼 인민전선의 발전에 발맞춰 성립시킨 통일전선 정당이라고 규정했다. 강만길의 민족 통일전선 연구에 대해서는 헤게모니 관점을 배제한 나이브한 통일전선론이라는 비판이 있었다. 이에 대해 강만길은 한국 민족해방운동사에서는 계급보다 민족이 중요했다고 강조하고, 우리 역사 속의 통일전선이 지닌 세계사적 보편성과 동아시아적 특수성을 밝히고자 했다."분단시대의 역사인식"(1978) 이후 강만길 역사학의 과제는 분단극복 사론의 수립이었다. 그 내용은 첫째, 식민지 시대 민족해방운동은 좌우 노선으로 분립되어 있는 것만이 아니라 하나의 통일전선을 형성하기 위한 과정이었음을 밝히고, 둘째, 해방 후의 민족국가 건설 문제를 포함해서 통일 민족국가 수립 운동으로서 민족해방 운동사를 서술하는 것이었다. 강만길은 1991년에 "조선민족혁명당과 통일전선"을 펴냈다. 1980년대 민족 통일전선 운동 연구의 집대성이었다. 이 책은 민족혁명당을 사실상의 좌우합작 통일전선이자, 일본 제국주의 중국 본토 침략을 내다본 민족해방운동 전선이 세계 반파쇼 인민전선의 발전에 발맞춰 성립시킨 통일전선 정당이라고 규정했다. 강만길의 민족 통일전선 연구에 대해서는 헤게모니 관점을 배제한 나이브한 통일전선론이라는 비판이 있었다. 이에 대해 강만길은 한국 민족해방운동사에서는 계급보다 민족이 중요했다고 강조하고, 우리 역사 속의 통일전선이 지닌 세계사적 보편성과 동아시아적 특수성을 밝히고자 했다.N
Deep Ecology in Blakes Milton: Corporeal Pastoral and Mental Georgic
No full textThis article examines the representation of nature, the body, and labor in William Blakes Milton to elucidate the poems ecocritical implications, especially its contribution to deep ecology. Major works of Blake ecocriticism have analyzed Milton as a poem that exposes the problems of the bourgeoning Industrial Revolution in early nineteenth-century Britain, as they center their arguments on the well-known phrase, Dark Satanic Mills. On the contrary, this study sides with another group of ecocritics, who foreground his deep ecology that questions the ontological assumptions and premises of modernity, deconstructing the dichotomies of human and nature, and mind and body, as well as proffering the alternative views of self, community, space, and time. To demonstrate the deep ecological significance of Milton, the article supplements ecocritical inquiry with the study of genres, analyzing how Blake deploys and reinvents pastoral and georgic in his depiction of nature, space, the body, subjectivity, and labor. I argue that Blake constructs what I term corporeal pastoral by locating the power for creating the new earth and heaven, not in beautiful nature or leisurely life, but within the human body or a Globule. Furthermore, Blake creates mental georgic by representing intellectual, social, and cultural struggles to transform the structure of human existence through the metaphor of labor. In doing so, Milton registers the ways in which the pastoral and georgic genres converge with one another in such a way as to enhance Blakes ecological visions. While the corporeal pastoral in Milton provides an alternative worldview and ontology, the mental georgic delineates the concrete methods and strategies needed to facilitate the advancement of human liberation. Together, the corporeal pastoral and mental georgic for Blake constitute the theory and practice of deep ecology.N
Spectrophotometric Reverberation Mapping of Intermediate-mass Black Hole NGC 4395
No full textUnderstanding the origins of massive black hole seeds and their coevolution with their host galaxy requires studying intermediate-mass black holes (IMBHs) and estimating their mass. However, measuring the masses of these IMBHs is challenging, due to the high-spatial-resolution requirement. Spectrophotometric reverberation monitoring is performed for a low-luminosity Seyfert 1 galaxy, NGC 4395, to measure the size of the broad-line region and black hole mass. The data were collected using the 1.3 m Devasthal fast optical telescope and 3.6 m Devasthal optical telescope at ARIES, Nainital, over two consecutive days in 2022 March. The analysis revealed strong emission lines in the spectra and light curves of the merged 5100 & Aring; spectroscopic continuum flux (f(5100)) with the photometric continuum V band and H alpha, with fractional variabilities of 6.38% and 6.31% respectively. In comparison to several previous studies with lag estimation <90 minutes, our calculated H alpha lag supersedes them by 125.0-6.1+6.2 minutes, using the ICCF and JAVELIN methods. The velocity dispersion (sigma(line)) of the broad-line clouds is measured to be 544.7-25.1+22.4 km s(-1), yielding a black hole mass of similar to 2.2(-0.2)(+0.2)x10(4)M(circle dot) and an Eddington ratio of 0.06.Y
Discovery of a Small-Molecule Inhibitor Targeting the Biofilm Regulator BrpT in Vibrio vulnificus
No full textVibrio vulnificus, an opportunistic human pathogen, employs biofilm formation as a key survival and virulence mechanism. BrpT, a transcriptional regulator, is essential for V. vulnificus biofilm development by regulating the expression of biofilm-related genes. In this study, we aimed to identify a small molecule inhibitor of BrpT to combat V. vulnificus biofilm formation. High-throughput screening of 7,251 compounds using an Escherichia coli reporter strain carrying the arabinose-inducible brpT gene and a BrpT-activated promoter fused to the luxCDABE operon identified a hit compound, BTI (BrpT Inhibitor). BTI potently inhibited BrpT activity in V. vulnificus (EC50 of 6.48 mu M) without affecting bacterial growth or host cell viability. Treatment with BTI significantly reduced the expression of the BrpT regulon and impaired biofilm formation and colony rugosity in V. vulnificus, thus increasing its susceptibility to antibiotics. In vitro biochemical analyses revealed that BTI directly binds to BrpT and inhibits its transcriptional regulatory activity. The identification of BTI as a specific inhibitor of BrpT that effectively diminishes V. vulnificus biofilm formation provides a promising foundation for the development of novel anti-biofilm strategies, with the potential to address the growing challenge of antibiotic resistance and improve the treatment of biofilm-associated infections.N
Device Parameter Extraction Method for Training Performance Predicting Models
No full textFor performance modeling using machine learning (ML), parameters that characterize transistors can be extracted and used as data for an ML model to predict circuit performance. However, generating and providing proper training data (e.g., device parameters for given bias voltage levels of the transistor's drain/gate/source) is crucial for the accuracy of the performance predicting model, as the prediction outcomes may vary depending on how the training data is generated. In this paper, we validate that the prediction error of an ML-based performance model can be reduced by employing the proposed method that extracts device parameters by choosing five bias voltage levels based on the threshold voltage (Vth).N
Atmospheric Rivers in East Asia Summer as the Continuum of Extratropical and Monsoonal Moisture Plumes
No full textEast Asian atmospheric rivers (ARs) exhibit the most pronounced activity in summer with significant impacts on monsoon rainfall. However, their occurrence mechanisms are yet to be revealed in detail. In this study, we unravel the inherently complex nature of East Asian summer ARs by applying a multiscale index that quantifies the relative importance of high-frequency (HF) and low-frequency (LF) moisture transports in AR development. It is found that both HF and LF processes contribute to shaping the summertime ARs in East Asia, contrasting to the wintertime ARs dominated by HF processes. Stratification of ARs with the multiscale index reveals that HF-dominant ARs are driven by baroclinically deepening extratropical cyclones, analogous to the widely accepted definition of canonical ARs. In contrast, LF-dominant ARs result from an enhanced monsoon southwesterly between a quasi-stationary cyclone and an anticyclone with the latter being the anomalous expansion of the western North Pacific subtropical high. Such a pattern is reminiscent of the classical monsoon rainband. While HF-dominant ARs are transient, LF-dominant ARs are quasi-stationary with a higher potential for prolonged local impacts. The intermediate ARs, constituting a majority of East Asian summer ARs, exhibit synoptic conditions that combine HF- and LF-dominant ARs. Therefore, East Asian summer ARs cannot be explained by a single parent system but should be considered as a continuum of extratropical-cyclone-induced and fl uctuating monsoon-flow-induced moisture plumes. This fi nding would serve as a base for the advanced understanding of hydrological impacts, variability, and projected change of East Asian ARs. SIGNIFICANCE STATEMENT: Despite the accumulation of studies on summertime atmospheric rivers (ARs) in East Asia, a comprehensive explanation for their occurrence mechanisms remains elusive. This study disentangles their complicated nature through case-level multiscale analyses. In contrast to wintertime ARs, summertime ARs are shaped by both high- and low-frequency moisture transports. The high-frequency moisture transport is associated with migratory extratropical cyclones which are suppressed but still active in summer, while the low-frequency moisture transport arises from the fl uctuation of a quasi-stationary monsoon southwesterly along the periphery of the western North Pacific subtropical high. The varying relative contribution of high- and low-frequency components from one AR to another suggests that East Asian summer ARs represent a continuum of extratropical and monsoonal moisture plumes.N