STaSy: Score-based Tabular data Synthesis

Tabular data synthesis is a long-standing research topic in machine learning. Many different methods have been proposed over the past decades, ranging from statistical methods to deep generative methods. However, it has not always been successful due to the complicated nature of real-world tabular data. In this paper, we present a new model named Score-based Tabular data Synthesis (STaSy) and its training strategy based on the paradigm of score-based generative modeling. Despite the fact that score-based generative models have resolved many issues in generative models, there still exists room for improvement in tabular data synthesis. Our proposed training strategy includes a self-paced learning technique and a fine-tuning strategy, which further increases the sampling quality and diversity by stabilizing the denoising score matching training. Furthermore, we also conduct rigorous experimental studies in terms of the generative task trilemma: sampling quality, diversity, and time. In our experiments with 15 benchmark tabular datasets and 7 baselines, our method outperforms existing methods in terms of task-dependant evaluations and diversity. Code is available at https://github.com/JayoungKim408/STaSy.Comment: 27 pages, Accepted by ICLR 2023 for spotlight presentation, Official code: https://github.com/JayoungKim408/STaS

Older Adults without Care Partners: A Scoping Review of Current Evidence

As a field, aging scholars must attend to the broader, growing population of those without an available care partner. These are old adults who, either due to the absence or unavailability of family, children, spouse, neighbors, friends, or other social network members, find themselves in old age without the type of “informal” care providers that are the backbone of caregiving in the U.S. A vital next step will be to expand our knowledge in the following areas through a scoping review: 1) Where this population is most likely to face risks and vulnerabilities; 2) The adverse health and social well-being consequences of having no care partner. And, conversely, any health and social well-being benefits for this population; and 3) Any interventions that have been developed and tested for the health and social well-being of this population

Human mini-blood–brain barrier models for biomedical neuroscience research: a review

© 2022, The Author(s).The human blood–brain barrier (BBB) is a unique multicellular structure that is in critical demand for fundamental neuroscience studies and therapeutic evaluation. Despite substantial achievements in creating in vitro human BBB platforms, challenges in generating specifics of physiopathological relevance are viewed as impediments to the establishment of in vitro models. In this review, we provide insight into the development and deployment of in vitro BBB models that allow investigation of the physiology and pathology of neurological therapeutic avenues. First, we highlight the critical components, including cell sources, biomaterial glue collections, and engineering techniques to reconstruct a miniaturized human BBB. Second, we describe recent breakthroughs in human mini-BBBs for investigating biological mechanisms in neurology. Finally, we discuss the application of human mini-BBBs to medical approaches. This review provides strategies for understanding neurological diseases, a validation model for drug discovery, and a potential approach for generating personalized medicine.11Nsciescopuskc

Direct high-resolution label-free imaging of cellular nanostructure dynamics in living cells

We report the application of an optical microscope equipped with a high-resolution dark-field condenser for detecting dynamic responses of cellular nanostructures in real time. Our system provides an easy-to-use technique to visualize biological specimens without any staining. This system can visualize the dynamic behavior of nanospheres and nanofibers, such as F-actin, at the leading edges of adjacent neuronal cells. We confirmed that the nanofibers imaged with this high-resolution optical microscopic technique are F-actin by using fluorescence microscopy after immunostaining the F-actin of fixed cells. Furthermore, cellular dynamics are enhanced by applying noncontact electric field stimulation through a transparent graphene electric field stimulator. High-resolution label-free optical microscopy enables the visualization of nanofiber dynamics initiated by filopodial nanofiber contacts. In conclusion, our optical microscopy system allows the visualization of nanoscale cellular dynamics under various external stimuli in real time without specific staining. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.101sciescopu

Suppressing storage-induced degradation of Li7La3Zr2O12 via encapsulation with hydrophobicity-tailored polymer nanolayer

Solid-state batteries have been proposed as an alternative to conventional lithium-ion batteries to resolve safety issues. Biphasic solid electrolytes (BSEs) based on Li7La3Zr2O12 (LLZO) and a polymer phase have been widely studied because LLZO has high Li+ conductivity and chemical/electrochemical compatibility with Li metal. However, LLZO reacts with H2O and CO2 during storage in air, forming lithium carbonate (Li2CO3) layers on the surface. The extremely low Li+ conductivity of Li2CO3 degrades the Li+-conduction properties of LLZO-based BSEs. Herein, we propose an effective approach to improve the air-stability of LLZO via encapsulation with a hydrophobicity-tailored, Li+-conducting polymer nanolayer. Polyurethane-based polymers are designed to have high hydrophobicity by tuning soft segments and chain extenders and successfully encapsulate the LLZO surface with a thickness of ∼10 nm (P-LLZO). Accelerated durability tests (ADTs) under controlled concentrations of O2, H2O, and CO2 indicate that LLZO encapsulation with hydrophobic polymer effectively mitigates storage-induced degradation by preventing direct contact between LLZO and H2O/CO2. ADT-tested P-LLZO BSE exhibits higher ionic conductivity (σ = 1.3 × 10−4 S cm−1 at 60 °C) compared with that of ADT-tested LLZO BSE (σ = 3.6 × 10−5 S cm−1). A solid-state Li battery with ADT-tested P-LLZO BSE shows enhanced cycling stability than that with ADT-tested LLZO BSE, proving the efficacy of polymer encapsulation. The findings are essential for understanding the role of interfacial engineering in mitigating the degradation of Li+-conduction properties and developing highly conductive LLZO-based BSEs. © 2023FALS

Sensitivity maximized near-field scanning optical microscope with dithering sample stage

We developed a new scheme for a higher sensitivity near-field scanning optical microscope (NSOM) by using a dithering sample stage rather than a dithering probe for the constant gap control between probe and sample. In a conventional NSOM, which use tip dithering feedback mechanism, the Q factor drastically decreases from 7783 to 1000 (13%) or even to 100 (1%) because harmonic oscillating characteristic is deteriorated owing to the large change of stiffness and mass of one prong of tuning fork when a probe is attached to it. In our proposed scheme, on the other hand, we use sample dithering feedback mechanism, where the probe is not attached to the tuning fork and the sample is loaded directly onto the surface of dithering tuning fork. Thus, the Q factor does not decrease significantly, from only 7783 to 7480 (96%), because the loaded sample hardly changes the stiffness and mass of tuning fork. Accordingly, gap control between the immobile fiber probe and the dithering sample is performed precisely by detecting the shear force with high sensitivity. Consequently, the extremely high Q factor enables clear observation of graphene sheets with sub-nanometer vertical resolution, which is not possible with a conventional NSOM setup

Amperometric microsensors monitoring glutamate-evoked in situ responses of nitric oxide and carbon monoxide from live human neuroblastoma cells

In the brain, nitric oxide (NO) and carbon monoxide (CO) are important signaling gases which have multifaceted roles, such as neurotransmitters, neuromodulators, and vasodilators. Even though it is difficult to measure NO and CO in a living system due to their high diffusibility and extremely low release levels, electrochemical sensors are promising tools to measure in vivo and in vitro NO and CO gases. In this paper, using amperometric dual and septuple NO/CO microsensors, real-time NO and CO changes evoked by glutamate were monitored simultaneously for human neuroblastoma (SH-SY5Y) cells. In cultures, the cells were differentiated and matured into functional neurons by retinoic acid and brain-derived neurotrophic factor. When glutamate was administrated to the cells, both NO and CO increases and subsequent decreases returning to the basal levels were observed with a dual NO/CO microsensor. In order to facilitate sensor’s measurement, a flower-type septuple NO/CO microsensor was newly developed and confirmed in terms of the sensitivity and selectivity. The septuple microsensor was employed for the measurements of NO and CO changes as a function of distances from the position of glutamate injection. Our sensor measurements revealed that only functionally differentiated cells responded to glutamate and released NO and CO. © 2017 by the authors. Licensee MDPI, Basel, Switzerland

Hyperspectral fluorescence imaging for cellular iron mapping in the in vitro model of Parkinson's disease

Parkinson's disease (PD) is characterized by progressive dopaminergic cell loss in the substantia nigra (SN) and elevated iron levels demonstrated by autopsy. Direct visualization of iron with live imaging techniques has not yet been successful. The aim of this study is to visualize and quantify the distribution of cellular iron using an intrinsic iron hyperspectral fluorescence signal. The 1-methyl-4-phenylpyridinium (MPP+)-induced cellular model of PD was established in SHSY5Y cells exposed to iron with ferric ammonium citrate (FAC, 100 ìM). The hyperspectral fluorescence signal of iron was examined using a high-resolution dark-field optical microscope system with signal absorption for the visible/near infrared spectral range. The 6-h group showed heavy cellular iron deposition compared with the 1-h group. The cellular iron was dispersed in a small particulate form, whereas the extracellular iron was aggregated. In addition, iron particles were found to be concentrated on the cell membrane/edge of shrunken cells. The iron accumulation readily occurred in MPP+-induced cells, which is consistent with previous studies demonstrating elevated iron levels in the SN. This direct iron imaging could be applied to analyze the physiological role of iron, and its application might be expanded to various neurological disorders involving metals, such as copper, manganese, or zinc. © The Authors.1481sciescopu

Amperometric Microsensors Monitoring Glutamate-Evoked In Situ Responses of Nitric Oxide and Carbon Monoxide from Live Human Neuroblastoma Cells

In the brain, nitric oxide (NO) and carbon monoxide (CO) are important signaling gases which have multifaceted roles, such as neurotransmitters, neuromodulators, and vasodilators. Even though it is difficult to measure NO and CO in a living system due to their high diffusibility and extremely low release levels, electrochemical sensors are promising tools to measure in vivo and in vitro NO and CO gases. In this paper, using amperometric dual and septuple NO/CO microsensors, real-time NO and CO changes evoked by glutamate were monitored simultaneously for human neuroblastoma (SH-SY5Y) cells. In cultures, the cells were differentiated and matured into functional neurons by retinoic acid and brain-derived neurotrophic factor. When glutamate was administrated to the cells, both NO and CO increases and subsequent decreases returning to the basal levels were observed with a dual NO/CO microsensor. In order to facilitate sensor’s measurement, a flower-type septuple NO/CO microsensor was newly developed and confirmed in terms of the sensitivity and selectivity. The septuple microsensor was employed for the measurements of NO and CO changes as a function of distances from the position of glutamate injection. Our sensor measurements revealed that only functionally differentiated cells responded to glutamate and released NO and CO