Korea University

About: Korea University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Population & Thin film. The organization has 39756 authors who have published 82424 publications receiving 1860927 citations. The organization is also known as: Bosung College & Bosung Professional College.

Mitochondria-immobilized pH-sensitive off-on fluorescent probe.

Abstract: We report here a mitochondria-targetable pH-sensitive probe that allows for a quantitative measurement of mitochondrial pH changes, as well as the real-time monitoring of pH-related physiological effects in live cells. This system consists of a piperazine-linked naphthalimide as a fluorescence off–on signaling unit, a cationic triphenylphosphonium group for mitochondrial targeting, and a reactive benzyl chloride subunit for mitochondrial fixation. It operates well in a mitochondrial environment within whole cells and displays a desirable off–on fluorescence response to mitochondrial acidification. Moreover, this probe allows for the monitoring of impaired mitochondria undergoing mitophagic elimination as the result of nutrient starvation. It thus allows for the monitoring of the organelle-specific dynamics associated with the conversion between physiological and pathological states.

Emotion categorization of body expressions in narrative scenarios

Abstract: Humans can recognise emotions expressed through body motion with high accuracy even when the stimuli are impoverished. However, most of the research on body motion has relied on exaggerated displays of emotions. In this paper we present two experiments where we investigated whether emotional body expressions could be recognised when they were recorded during natural narration. Our actors were free to use their entire body, face and voice to express emotions, but our resulting visual stimuli used only the upper body motion trajectories in the form of animated stick figures. Observers were asked to perform an emotion recognition task on short motion sequences using a large and balanced set of emotions (amusement, joy, pride, relief, surprise, anger, disgust, fear, sadness, shame and neutral). Even with only upper body motion available, our results show recognition accuracy significantly above chance level and high consistency rates among observers. In our first experiment, that used more classic emotion induction setup, all emotions were well recognised. In the second study that employed narrations, four basic emotion categories (joy, anger, fear and sadness), three non-basic emotion categories (amusement, pride and shame) and the "neutral" category were recognised above chance. Interestingly, especially in the second experiment, observers showed a bias towards anger when recognising the motion sequences for emotions. We discovered that similarities between motion sequences across the emotions along such properties as mean motion speed, number of peaks in the motion trajectory and mean motion span can explain a large percent of the variation in observers' responses. Overall, our results show that upper body motion is informative for emotion recognition in narrative scenarios.

Theranostic Probe Based on Lanthanide-Doped Nanoparticles for Simultaneous In Vivo Dual-Modal Imaging and Photodynamic Therapy

Abstract: Dual-modal in vivo tumor imaging and photodynamic therapy using hexagonal NaYF(4):Yb,Er/NaGdF(4) core-shell upconverting nanoparticles combined with a photosensitizer, chlorin e6, is reported. Tumors can be clearly observed not only in the upconversion luminescence image but also in the magnetic resonance image. In vivo photodynamic therapy by systemic administration is demonstrated under 980 nm irradiation.

Rapid induction and long-term self-renewal of primitive neural precursors from human embryonic stem cells by small molecule inhibitors

Abstract: Human embryonic stem cells (hESCs) hold enormous promise for regenerative medicine. Typically, hESC-based applications would require their in vitro differentiation into a desirable homogenous cell population. A major challenge of the current hESC differentiation paradigm is the inability to effectively capture and, in the long-term, stably expand primitive lineage-specific stem/precursor cells that retain broad differentiation potential and, more importantly, developmental stage-specific differentiation propensity. Here, we report synergistic inhibition of glycogen synthase kinase 3 (GSK3), transforming growth factor β (TGF-β), and Notch signaling pathways by small molecules can efficiently convert monolayer cultured hESCs into homogenous primitive neuroepithelium within 1 wk under chemically defined condition. These primitive neuroepithelia can stably self-renew in the presence of leukemia inhibitory factor, GSK3 inhibitor (CHIR99021), and TGF-β receptor inhibitor (SB431542); retain high neurogenic potential and responsiveness to instructive neural patterning cues toward midbrain and hindbrain neuronal subtypes; and exhibit in vivo integration. Our work uniformly captures and maintains primitive neural stem cells from hESCs.

The Safety of Objects: Materialism, Existential Insecurity, and Brand Connection

Abstract: Over the past 2 decades, a large body of research has examined how materialism is formed and how this value influences well-being. Although these studies have substantially contributed to our understanding of materialism, they shed little light on this value's relationship to consumer behavior. Our research seeks to address this gap by examining the influence of materialism on self- and communal-brand connections. We ground our conceptualization in terror management theory and suggest that materialistic individuals form strong connections to their brands as a response to existential insecurity. We test this premise by conducting a national survey among 314 adults as well as an experiment among 125 college students. Our results provide broad support for our thesis and suggest that the fear of death encourages materialistic individuals to form strong connections with their brands.