1,315 results match your criteria: "Daegu-Gyeongbuk Institute of Science and Technology[Affiliation]"

Microscopic and Mesoscopic Dual Postsynthetic Modifications of Metal-Organic Frameworks.

Angew Chem Int Ed Engl

August 2020

Department of Emerging Materials Science, Daegu-Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Dalseong-gun, Daegu, 42988, Korea.

We report the dual postsynthetic modification (PSM) of a metal-organic framework (MOF) involving the microscopic conversion of C-H bonds into C-C bonds and the mesoscopic introduction of hierarchical porosity. MOF crystals underwent single-crystal-to-single-crystal transformations during the electrophilic aromatic substitution of Co (m-DOBDC) (m-DOBDC =4,6-dioxo-1,3-benzenedicarboxylate) with alkyl halides and formaldehyde. The steric hindrance caused by the proximity of the introduced functional groups to the coordination bonds reduced bond stability and facilitated the transformation into hierarchically porous mesostructures by etching with in situ generated protons (hydroniums) and halides.

View Article and Find Full Text PDF

Circadian oscillation is an essential process that influences many physiological and biological mechanisms and a decrease of circadian genes is associated with many diseases such as cancer. Despite many efforts to identify the detailed mechanism for decreasing circadian genes and recovering reduced circadian genes in cancer, it is still largely unknown. We found that BMAL1 was reduced in tumor hypoxia-induced acidosis, and recovered by selectively targeting acidic pH in breast cancer cell lines.

View Article and Find Full Text PDF

Here we present our study on an impact print-type hot embossing process which can create dot patterns with various designs, widths, and depths in real time on polymer film. In addition, we implemented a control system for the on-off motion and position of the impact header to engrave different dot patterns. We performed dot patterning on various polymer films, such as polyester (PET) film, polymethyl methacrylate (PMMA) film, and polyvinyl chloride (PVC) film.

View Article and Find Full Text PDF

Evolution of switchable aposematism: insights from individual-based simulations.

PeerJ

April 2020

Laboratory of Behavioral Ecology and Evolution, School of Biological Sciences, Seoul National University, Seoul, South Korea.

Some defended prey animals can switch on their normally hidden aposematic signals. This switching may occur in reaction to predators' approach (pre-attack signals) or attack (post-attack signals). Switchable aposematism has been relatively poorly studied, but we can expect that it might bring a variety of benefits to an aposmetic organism.

View Article and Find Full Text PDF

Understanding of ultrafast spin dynamics is crucial for future spintronic applications. In particular, the role of non-thermal electrons needs further investigation in order to gain a fundamental understanding of photoinduced demagnetization and remagnetization on a femtosecond time scale. We experimentally demonstrate that non-thermal electrons existing in the very early phase of the photoinduced demagnetization process play a key role in governing the overall ultrafast spin dynamics behavior.

View Article and Find Full Text PDF

Objective: To assess whether 3-dimensional (3D) fractal dimension (FD) and lacunarity features from MRI can predict the meningioma grade.

Methods: This retrospective study included 131 patients with meningiomas (98 low-grade, 33 high-grade) who underwent preoperative MRI with post-contrast T1-weighted imaging. The 3D FD and lacunarity parameters from the enhancing portion of the tumor were extracted by box-counting algorithms.

View Article and Find Full Text PDF

Relative clause (RC) formation and center embedding (CE) are two primary syntactic operations fundamental for creating and understanding complex sentences. Ample evidence from previous cross-linguistic studies has revealed several similarities and differences between RC and CE. However, it is not easy to investigate the effect of pure syntactic constraints for RC and CE without the interference of semantic and pragmatic interactions.

View Article and Find Full Text PDF

The effects of micro-hole arrays in the thin metal films were studied as a method to release bending stress in flexible electrodes and flexible thin film transistors (TFTs). Interest in flexible electronics is increasing, and many approaches have been suggested to solve the issue of the electrical failure of electrodes or electrical components such as TFTs after repeated bending. Here, we demonstrate a micro-hole array structure as a common solution to release bending stress.

View Article and Find Full Text PDF

By simple soaking titanium dioxide (TiO) films in an aqueous NaS solution, we could prepare surface-modified photoanodes for application to dye-sensitized solar cells (DSSCs). An improvement in both the open-circuit voltage () and the fill factor () was observed in the DSSC with the 5 min-soaked photoanode, compared with those of the control cell without any modification. The UV-visible absorbance spectra, UPS valence band spectra, and dark current measurements revealed that the NaS modification led to the formation of anions on the TiO surface, and thereby shifted the conduction band edge of TiO in the negative (upward) direction, inducing an increase of 29 mV in the .

View Article and Find Full Text PDF

Distinct Developmental Features of Olfactory Bulb Interneurons.

Mol Cells

March 2020

Department of Brain and Cognitive Sciences, Graduate School, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea.

The olfactory bulb (OB) has an extremely higher proportionof interneurons innervating excitatory neurons than otherbrain regions, which is evolutionally conserved across species.Despite the abundance of OB interneurons, little is knownabout the diversification and physiological functions ofOB interneurons compared to cortical interneurons. In thisreview, an overview of the general developmental processof interneurons from the angles of the spatial and temporalspecifications was presented.

View Article and Find Full Text PDF

Infrared transparent electrodes (IR-TEs) have recently attracted much attention for industrial and military applications. The simplest method to obtain high IR transmittance is to reduce the electrode film thickness. However, for films several tens of nanometres thick, this approach unintentionally suppresses conduction due to surface electron scattering.

View Article and Find Full Text PDF

A new type of ammonium vanadium bronze, (NH)VO, was synthesized by the hydrothermal method. The triclinic crystal structure (1̅) is successfully identified by the single-crystal X-ray diffraction method. The layered structure is similar to that of other vanadium bronzes but with an unprecedented stoichiometry and crystal structure.

View Article and Find Full Text PDF

All living organisms are unavoidably exposed to various endogenous and environmental stresses that trigger potentially fatal DNA damage, including double-strand breaks (DSBs). Although a growing body of evidence indicates that DNA damage is one of the prime drivers of aging in animals, little is known regarding the importance of DNA damage and its repair on lifespan control in plants. We found that the level of DSBs increases but DNA repair efficiency decreases as Arabidopsis leaves age.

View Article and Find Full Text PDF

Programming effects of maternal stress on the circadian system of adult offspring.

Exp Mol Med

March 2020

Department of Brain and Cognitive Sciences, Scranton College, Ewha Womans University, Seoul, 03760, Korea.

Maternal stress has long-lasting influences on the brain functions of offspring, and several brain regions have been proposed to mediate such programming. Although perinatal programming of crosstalk between the circadian and stress systems has been proposed, the functional consequences of prenatal stress on the circadian system and the underlying mechanisms remain largely unknown. Therefore, we investigated whether exposing pregnant mice to chronic restraint stress had prolonged effects on the suprachiasmatic nucleus (SCN), which bears the central pacemaker for mammalian circadian rhythms, of offspring.

View Article and Find Full Text PDF

Circadian rhythm is an endogenous oscillation of about 24-h period in many physiological processes and behaviors. This daily oscillation is maintained by the molecular clock machinery with transcriptional-translational feedback loops mediated by clock genes including () and . Recently, it was revealed that gut microbiome exerts a significant impact on the circadian physiology and behavior of its host; however, the mechanism through which it regulates the molecular clock has remained elusive.

View Article and Find Full Text PDF

Rapid biodegradation of polyphenylene sulfide plastic beads by Pseudomonas sp.

Sci Total Environ

June 2020

School of Undergraduate Studies, College of Transdisciplinary Studies, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea. Electronic address:

Pseudomonas sp. isolated from soil, are bioremediating microorganisms that are capable of degrading various types of plastics. Polyphenylene sulfide (PPS) has the most excellent structural stability among general plastics and thus is extremely difficult to break down using physical or chemical methods.

View Article and Find Full Text PDF

We develop a novel smartphone-based spectral imaging otoscope for telemedicine and examine its capability for the mobile diagnosis of middle ear diseases. The device was applied to perform spectral imaging and analysis of an ear-mimicking phantom and a normal and abnormal tympanic membrane for evaluation of its potential for the mobile diagnosis. Spectral classified images were obtained via online spectral analysis in a remote server.

View Article and Find Full Text PDF

Regulation of stomatal development by stomatal lineage miRNAs.

Proc Natl Acad Sci U S A

March 2020

Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea;

Stomata in the plant epidermis play a critical role in growth and survival by controlling gas exchange, transpiration, and immunity to pathogens. Plants modulate stomatal cell fate and patterning through key transcriptional factors and signaling pathways. MicroRNAs (miRNAs) are known to contribute to developmental plasticity in multicellular organisms; however, no miRNAs appear to target the known regulators of stomatal development.

View Article and Find Full Text PDF

In this study, we synthesized a Prussian blue (PB)-embedded macroporous carboxymethyl cellulose nanofibril (CMCNF) membrane for facile cesium (Cs) removal. The PB was formed in situ at Fe sites on a CMCNF framework cross-linked using FeCl as a cross-linking agent. Cubic PB particles of size 5-20 nm were observed on the macroporous CMCNF membrane surface.

View Article and Find Full Text PDF

Activity-dependent regulation of gene expression is critical in experience-mediated changes in the brain. Although less appreciated than transcriptional control, translational control is a crucial regulatory step of activity-mediated gene expression in physiological and pathological conditions. In the first part of this review, we overview evidence demonstrating the importance of translational controls under the context of synaptic plasticity as well as learning and memory.

View Article and Find Full Text PDF

Biomolecular piezoelectric materials are considered a strong candidate material for biomedical applications due to their robust piezoelectricity, biocompatibility, and low dielectric property. The electric field has been found to affect tissue development and regeneration, and the piezoelectric properties of biological materials in the human body are known to provide electric fields by pressure. Therefore, great attention has been paid to the understanding of piezoelectricity in biological tissues and its building blocks.

View Article and Find Full Text PDF

Indoprofen prevents muscle wasting in aged mice through activation of PDK1/AKT pathway.

J Cachexia Sarcopenia Muscle

August 2020

Department of Molecular Cell Biology, Single Cell Network Research Center, Sungkyunkwan University, Suwon, South Korea.

Background: Muscle wasting, resulting from aging or pathological conditions, leads to reduced quality of life, increased morbidity, and increased mortality. Much research effort has been focused on the development of exercise mimetics to prevent muscle atrophy and weakness. In this study, we identified indoprofen from a screen for peroxisome proliferator-activated receptor γ coactivator α (PGC-1α) inducers and report its potential as a drug for muscle wasting.

View Article and Find Full Text PDF

Photoreaction characteristics of ferrous oxalate recovered from wastewater.

Chemosphere

June 2020

Department of Environmental Engineering, Mokpo National University, 1666 Yongsan-ro, Cheongye-myeon, Muan-gun, Jeollanam-do, 58554, Republic of Korea. Electronic address:

Photoreaction with the Fe(III)-oxalate complex has been reported to play an important role in various photochemical reactions in the natural atmospheric environment, and are applicable to treat various recalcitrant compounds in wastewater. We previously showed that a Fe(II) oxalate (FeOx) crystal can be recovered from the wastewater generated from soil washing, which can then be applied to the photoreaction for degradation of recalcitrant pollutants; however, photoreactions with FeOx compounds have not been fully reported yet. Therefore, this study aims to investigate the photoreaction characteristics of FeOx recovered from wastewater, to demonstrate the feasibility of its application to wastewater treatment.

View Article and Find Full Text PDF

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

View Article and Find Full Text PDF

The interaction of a carbon nanotube (CNT) with various aromatic molecules, such as aniline, benzophenone, and diphenylamine, was studied using density functional theory able to compute intermolecular weak interactions (B3LYP-D3). CNTs of varying lengths were used, such as 4-CNT, 6-CNT, and 8-CNT (the numbers denoting relative lengths), with the lengths being chosen appropriately to save computation times. All aromatic molecules were found to exhibit strong intermolecular binding energies with the inner surface of the CNT, rather than the outer surface.

View Article and Find Full Text PDF