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1.
Phys Rev Lett ; 132(3): 036702, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38307068

RESUMEN

Altermagnetism is a newly identified fundamental class of magnetism with vanishing net magnetization and time-reversal symmetry broken electronic structure. Probing the unusual electronic structure with nonrelativistic spin splitting would be a direct experimental verification of an altermagnetic phase. By combining high-quality film growth and in situ angle-resolved photoemission spectroscopy, we report the electronic structure of an altermagnetic candidate, α-MnTe. Temperature-dependent study reveals the lifting of Kramers degeneracy accompanied by a magnetic phase transition at T_{N}=267 K with spin splitting of up to 370 meV, providing direct spectroscopic evidence for altermagnetism in MnTe.

2.
Nanotechnology ; 35(12)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38064735

RESUMEN

Ferromagnetic insulators (FMIs) are intriguing not only due to their rare nature, but also due to their potential applications in spintronics and various electronic devices. One of its key promising applications is based on an FMI-induced magnetic proximity effect, which can impose an effective time-reversal symmetry breaking on the target ultrathin layer to realize novel emergent phenomena. Here, we conduct systematic studies on thin film LaCoO3, an insulator known to be ferromagnet under tensile strain, with varying thicknesses, to establish it as an FMI platform to be integrated in heterostructures. The optimal thickness of the LaCoO3layer, providing a smooth surface and robust ferromagnetism with large remanence, is determined. A heterostructure consisting of an ultrathin target layer (2 uc SrRuO3), the LaCoO3FMI layer, and the La0.5Sr0.5CoO3conducting layer has been fabricated and the angle-resolved photoemission spectroscopy measurement on the multi-layer system demonstrates a sharp Fermi edge and a well-defined Fermi surface without the charging effect. This demonstrates the feasibility of the proposed heterostructure using LaCoO3thin film as the FMI layer, and further lays a groundwork to investigate the magnetic proximity induced phases in quantum materials.

3.
Heliyon ; 9(11): e21213, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37954256

RESUMEN

To guarantee the right to move for residents in areas where public transportation is insufficient, research is needed to identify vulnerable areas and prepare measures. This paper defines the vulnerable regions of public transportation within various city types in Korea. In order to identify appropriate areas to apply the Demand Responsive Transit (DRT), the regions with vulnerability were compared with a specific city (Yangsan-si) which already the DRT system was successfully adopted. To collect monthly bus data, web-data crawling method was performed and processed with coordinating program by matching GPS coordinate. The public transportation demand was predicted for each grid cell size (100 m, 250 m, and 500 m) by different methodologies. Various data mining models based on regression were analyzed to predict bus demand of vulnerable areas. Among models, a modified model was suggested to combine Automated machine learning models for high prediction performance. The modified model outperformed other methods as 0.685 and prediction performance was appropriate at 100 m rectangle grid. Regional characters of DRT bus allocation areas were extracted by K-means clustering method and differentiate urban and suburban types. The findings of this study provide valuable insights into conditions that DRT bus stop can be installed. The urban bus stop areas located in metropolitan cities and the suburban bus stop allocation areas located in countryside. The study results can be used as policy data for the successful introduction to prevent social exclusion and improve resident welfare in the future.

4.
Artículo en Inglés | MEDLINE | ID: mdl-37436803

RESUMEN

A Gram-stain-negative, non-motile by gliding and moderately halophilic rod-shaped bacterium HN-2-9-2T was isolated from seawater in Tongyeong, Republic of Korea. The strain grew at concentrations of 0.5‒7 % (w/v) NaCl, at pH 5.5‒8.5 and in a temperature range of 18‒45 °C. HN-2-9-2T shared the highest 16S rRNA gene sequence percentage with Salinimicrobium xinjiangense BH206T (98.2 %). The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridisation (dDDH) values between HN-2-9-2T and the S. xinjiangense BH206T were 76.0 %, 81.9 % and 19.7 %, respectively. The genome comprised 3 509 958 bp with a DNA G+C content of 43.0%. HN-2-9-2T contained MK-6 as the sole menaquinone. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 0 3-OH, iso-C16 : 0, iso-C15 : 1G and summed feature 9, comprising iso-C17 : 1ω6c/C16 : 1 10-methyl. The polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, two unidentified aminolipids, an unidentified glycolipid and six unidentified lipids. The polyphasic taxonomic properties indicate that the strain represents a novel species within the genus Salinimicrobium, for which the name Salinimicrobium tongyeongense sp. nov. is proposed. The type strain is HN-2-9-2T (=KCTC 82934T=NBRC 115920T).


Asunto(s)
Ácidos Grasos , Agua de Mar , Ácidos Grasos/química , ARN Ribosómico 16S/genética , Composición de Base , Filogenia , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Agua de Mar/microbiología , Vitamina K 2/química
5.
Antonie Van Leeuwenhoek ; 116(8): 791-799, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37227603

RESUMEN

The taxonomic position of strain EF45031T, isolated from the Neungam Carbonate hot spring, was examined using the polyphasic taxonomic approach. Strain EF45031T shared the highest percentage of 16S rRNA gene sequence with Brachybacterium nesterenkovii CIP 104813 T (97.7%). The average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA-DNA hybridization (dDDH) values between strain EF45031T and the type strains B. nesterenkovii CIP 104813 T and B. phenoliresistens Phenol-AT were 77.0%, 69.15%, 21.9% and 75.73%, 68.81%, 20.5%, respectively. Phylogenomic analysis using an up-to-date bacterial core gene (UBCG) set revealed that strain EF45031T belonged to the genus Brachybacterium. Growth occurred between 25 and 50 ℃ at pH 6.0-9.0 and could tolerate salinity up to 5% (w/v). Strain had anteiso-C15:0 and anteiso-C17:0 as major fatty acids. Menaquinone-7 (MK-7) was the predominant respiratory menaquinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, three aminolipids, and two unidentified glycolipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid as a diagnostic diamino acid. The genome comprised 2,663,796 bp, with a G + C content of 70.9%. Stress-responsive periplasmic chaperone/protease coding genes were identified in the genome of EF45031T and were not detected in other Brachybacterium species. The polyphasic taxonomic properties indicate that the strain represents a novel species within the genus Brachybacterium, for which the name Brachybacterium sillae sp. nov. is proposed. The type strain is EF45031T (= KCTC 49702 T = NBRC 115869 T).


Asunto(s)
Actinomycetales , Manantiales de Aguas Termales , Fosfolípidos/química , ARN Ribosómico 16S/genética , Ácidos Grasos/química , Filogenia , Vitamina K 2/química , ADN , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana
6.
Adv Mater ; 35(15): e2208833, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36739615

RESUMEN

Interfaces between dissimilar correlated oxides can offer devices with versatile functionalities, and great efforts have been made to manipulate interfacial electronic phases. However, realizing such phases is often hampered by the inability to directly access the electronic structure information; most correlated interfacial phenomena appear within a few atomic layers from the interface. Here, atomic-scale epitaxy and photoemission spectroscopy are utilized to realize the interface control of correlated electronic phases in atomic-scale ruthenate-titanate heterostructures. While bulk SrRuO3 is a ferromagnetic metal, the heterointerfaces exclusively generate three distinct correlated phases in the single-atomic-layer limit. The theoretical analysis reveals that atomic-scale structural proximity effects yield Fermi liquid, Hund metal, and Mott insulator phases in the quantum-confined SrRuO3 . These results highlight the extensive interfacial tunability of electronic phases, hitherto hidden in the atomically thin correlated heterostructure. Moreover, this experimental platform suggests a way to control interfacial electronic phases of various correlated materials.

7.
Nutrients ; 15(2)2023 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-36678181

RESUMEN

Microbial fermentation provides a valorization strategy, through biotransformation, to convert plant-derived raw materials into health-promoting agents. In this study, we have investigated the antioxidative activity of Abelmoschus manihot fermented with various Bacillaceae strains from specific environments and demonstrated the anti-inflammatory effects of Bacillus licheniformis CP6 fermented A. manihot extract (FAME) in lipopolysaccharide (LPS)-stimulated Raw264.7 macrophages. Of 1500 bacteria isolated from various specific environments, 47 extracellular protease- and amylase-producing strains with qualified presumption safety status, belonging to the family Bacillaceae, were selected for A. manihot fermentation. Among them, strain CP6, a halophilic bacterium isolated from Tongyeong seawater in Korea and identified as B. licheniformis, showed the highest antioxidant activity. In particular, FAME exerted anti-inflammatory effects on LPS-stimulated Raw264.7 macrophages. Consequently, FAME had a potent inhibitory effect on nitric oxide (NO) production in LPS-stimulated macrophages, without cytotoxicity. Moreover, FAME downregulated LPS-induced pro-inflammatory mediator and enzyme levels in LPS-induced Raw264.7 cells, including IL-1ß, IL-6, TNF-α, iNOS, and COX-2, compared to levels when cells were incubated in A. manihot extract (IAME). Further detailed characterization indicated that FAME suppresses inflammation by blocking NF-κB via IKK phosphorylation inhibition and IκB-α degradation and by downregulating NO production, and inflammatory mediators also decreased NF-κB translocation. Furthermore, FAME inhibited LPS-stimulated activation of MAPKs, including ERK1/2, JNK, and p38, compared to that with either IAME. Therefore, we suggest that FAME could be used for inflammation-related disorders.


Asunto(s)
Abelmoschus , Bacillus licheniformis , FN-kappa B/metabolismo , Transducción de Señal , Bacillus licheniformis/metabolismo , Lipopolisacáridos/farmacología , Fermentación , Antiinflamatorios/farmacología , Inflamación , Extractos Vegetales/farmacología , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo
8.
Microorganisms ; 10(12)2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36557626

RESUMEN

Thermophiles that produce extracellular hydrolases are of great importance due to their applications in various industries. Thermophilic enzymes are of interest for industrial applications due to their compatibility with industrial processes, and the availability of the organisms is essential to develop their full potential. In this study, a culture-dependent approach was used to identify thermophilic bacteria from five hot springs in Republic of Korea. Characterization, taxonomic identification, and extracellular hydrolase (amylase, lipase, and protease) activity of 29 thermophilic bacterial isolates from the Neungam carbonate, Mungang sulfur, Deokgu, Baegam, and Dongnae hot springs were investigated. Identification based on the full-length 16S rRNA gene sequence revealed that strains belonged to the phylum Bacillota and were classified as Aeribacillus, Bacillus, Caldibacillus, Geobacillus, and Thermoactinomyces genera. It was found that 22 isolates could produce at least one extracellular enzyme. Geobacillus, representing 41.4% of the isolates, was the most abundant. The highest amount of proteolytic and lipolytic enzymes was secreted by strains of the genus Geobacillus, whereas Caldibacillus species produced the highest amount of amylolytic enzyme. The Geobacillus species producing hydrolytic extracellular enzymes appeared to be the most promising.

9.
Arch Microbiol ; 205(1): 23, 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36509934

RESUMEN

The Gram-positive, nonmotile, rod-shaped bacterium EF45044T was isolated from a hot spring in Chungju, South Korea. The strain was able to grow at concentrations of 0‒5% (w/v) NaCl, at pH 6.0‒10.0 and in the temperature range of 18‒50 °C. Strain EF45044T showed the highest 16S rRNA gene sequence similarity (98.2%) with Microbacterium ketosireducens DSM 12510T, and the digital DNA‒DNA hybridization (dDDH), average amino acid identity (AAI), and average nucleotide identity (ANI) values were all lower than the accepted species threshold. Strain EF45044T contained MK‒12 and MK‒13 as the predominant respiratory quinones and anteiso‒C17:0, anteiso‒C15:0, and iso‒C16:0 as the major fatty acids. Diphosphatidylglycerol, phosphatidylglycerol, and glycolipid were detected as the major polar lipids. The cell-wall peptidoglycan contained ornithine. The DNA G + C content was 71.4 mol%. Based on the polyphasic data, strain EF45044T (= KCTC 49703T) presents a novel species of the genus Microbacterium, for which the name Microbacterium neungamense sp. nov. is proposed.


Asunto(s)
Ácidos Grasos , Microbacterium , ARN Ribosómico 16S/genética , Microbacterium/genética , Filogenia , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Ácidos Grasos/análisis , Hibridación de Ácido Nucleico , Fosfolípidos/química
10.
Biomed Res Int ; 2022: 2743046, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35692597

RESUMEN

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a novel infectious respiratory disease called COVID-19, which is threatening public health worldwide. SARS-CoV-2 spike proteins connect to the angiotensin converting enzyme 2 (ACE2) receptor through the receptor binding domain and are then activated by the transmembrane protease serine subtype 2 (TMPRSS2). The ACE2 receptor is highly expressed in human nasal epithelial cells. Nasal ciliated cells are primary targets for SARS-CoV-2 replication. However, the effect of SARS-CoV-2 on the upper respiratory tract remains unknown, thus leading to the purpose of our study. We investigate the effects of SARS-CoV-2 on cytokines and mucin expression in human nasal epithelial cells. Methods: We investigated the effects of the SARS-CoV-2 spike protein receptor binding domain (RBD) on cytokines (IL-1ß, IL-6, and IL-8) and MUC5AC/5B expression via real-time PCR, ELISA, periodic acid-Schiff (PAS) staining, and immunofluorescence staining in cultured human nasal epithelial cells. Results: The mRNA expression and protein production of cytokines (IL-1ß, IL-6, and IL-8) and MUC5AC/5B were increased by SARS-CoV-2 spike protein RBD. ACE2 receptor inhibitor suppressed the expression of cytokines (IL-1ß, IL-6, and IL-8) and MUC5AC/5B induced by SARS-CoV-2 spike protein RBD. Conclusions: SARS-CoV-2 induced cytokines (IL-1ß, IL-6, and IL-8) and MUC5AC/5B expression through the ACE 2 receptor in human nasal epithelial cells. Therefore, ACE2 receptor inhibitors can be an effective therapeutic option for SARS-CoV-2 infection.


Asunto(s)
COVID-19 , SARS-CoV-2 , Enzima Convertidora de Angiotensina 2 , Citocinas/metabolismo , Células Epiteliales/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Mucina 5AC/genética , Mucina 5AC/metabolismo , Mucina 5B/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Glicoproteína de la Espiga del Coronavirus
11.
BMC Complement Med Ther ; 22(1): 175, 2022 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-35754023

RESUMEN

BACKGROUND: Traditional Korean Medicine (TKM) is highly integrated with the modern health care system of South Korea and is actively used in the public health field. Since 2014, the Ministry of Health and Welfare of South Korea has supported the development of standard models for TKM-based health promotion programs. This study aimed to develop and evaluate a standard TKM-based health promotion program for disadvantaged children. METHODS: Using convenience sampling, we recruited 16 Community Children's Centers (CCCs) located in Busan and Yangsan, South Korea, which are welfare daytime facilities for children from socially disadvantaged families. The CCCs were divided into two groups of eight CCCs-intervention CCCs and control CCCs-through random allocation, and children in each group were selected as subjects for the study. For 12 weeks, the TKM-based health promotion program developed in this study along with the basic services of CCCs were applied to children in the intervention group, and only the basic services of CCCs were provided to children in the control group. Data were obtained through pre- and post-surveys with the legal representatives of the children prior to implementing the program and after the 12-week program, respectively. The outcome variables-the number of outpatient visits, absences, lateness/early leaves, infectious symptoms, and EuroQol-5D and EQ-visual analog scale scores-were measured and statistically compared between the groups by descriptive analysis, chi-square test, t-test, and difference-in-differences model with regression analysis. RESULTS: At baseline, there were 156 children in the intervention group and 153 children in the control group, among which 155 and 147 children, respectively, were included in the analysis. Results indicated that the number of outpatient visits was significantly lower (by 65%) in the intervention group than in the control group (p = 0.03), and this was similar in the sensitivity analysis. Regarding other outcome variables, the effects were not consistently significant. CONCLUSIONS: A standard TKM-based health promotion program has the potential to improve the health of disadvantaged children. In the future, studies with long-term interventions and a larger sample are needed to enhance the applicability of these programs in communities.


Asunto(s)
Promoción de la Salud , Medicina Tradicional Coreana , Niño , Humanos , Medicina Tradicional , República de Corea , Encuestas y Cuestionarios
12.
Biotechnol Bioeng ; 118(11): 4360-4374, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34309016

RESUMEN

Excavating the molecular details of many diverse enzymes from metagenomes remains challenging in agriculture, food, health, and environmental fields. We present a versatile method that accelerates metabolic enzyme discovery for highly selective gene capture in metagenomes using next-generation sequencing. Culture-independent enzyme mining of environmental DNA is based on a set of short identifying degenerate sequences specific for a wide range of enzyme superfamilies, followed by multiplexed DNA barcode sequencing. A strategy of 'focused identification of next-generation sequencing-based definitive enzyme research' enabled us to generate targeted enzyme datasets from metagenomes, resulting in minimal hands-on obtention of high-throughput biological diversity and potential function profiles, without being time-consuming. This method also provided a targeted inventory of predicted proteins and molecular features of metabolic activities from several metagenomic samples. We suggest that the efficiency and sensitivity of this method will accelerate the decryption of microbial diversity and the signature of proteins and their metabolism from environmental samples.


Asunto(s)
Código de Barras del ADN Taxonómico , Enzimas/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica
13.
Nat Commun ; 12(1): 4573, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34321473

RESUMEN

The mechanism of the enhanced superconductivity in monolayer FeSe/SrTiO3 has been enthusiastically studied and debated over the past decade. One specific observation has been taken to be of central importance: the replica bands in the photoemission spectrum. Although suggestive of electron-phonon interaction in the material, the essence of these spectroscopic features remains highly controversial. In this work, we conduct angle-resolved photoemission spectroscopy measurements on monolayer FeSe/SrTiO3 using linearly polarized photons. This configuration enables unambiguous characterization of the valence electronic structure with a suppression of the spectral background. We consistently observe high-order replica bands derived from various Fe 3d bands, similar to those observed on bare SrTiO3. The intensity of the replica bands is unexpectedly high and different between dxy and dyz bands. Our results provide new insights on the electronic structure of this high-temperature superconductor and the physical origin of the photoemission replica bands.

14.
Sci Adv ; 7(2)2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33523988

RESUMEN

Titanium monoxide (TiO), an important member of the rock salt 3d transition-metal monoxides, has not been studied in the stoichiometric single-crystal form. It has been challenging to prepare stoichiometric TiO due to the highly reactive Ti2+ We adapt a closely lattice-matched MgO(001) substrate and report the successful growth of single-crystalline TiO(001) film using molecular beam epitaxy. This enables a first-time study of stoichiometric TiO thin films, showing that TiO is metal but in proximity to Mott insulating state. We observe a transition to the superconducting phase below 0.5 K close to that of Ti metal. Density functional theory (DFT) and a DFT-based tight-binding model demonstrate the extreme importance of direct Ti-Ti bonding in TiO, suggesting that similar superconductivity exists in TiO and Ti metal. Our work introduces the new concept that TiO behaves more similar to its metal counterpart, distinguishing it from other 3d transition-metal monoxides.

15.
Nat Mater ; 20(2): 188-193, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33462465

RESUMEN

Spin excitations of magnetic thin films are the founding element for magnetic devices in general. While spin dynamics have been extensively studied in bulk materials, the behaviour in mesoscopic films is less known due to experimental limitations. Here, we employ resonant inelastic X-ray scattering to investigate the spectrum of spin excitations in mesoscopic Fe films, from bulk-like films down to three unit cells. In bulk samples, we find isotropic, dispersive ferromagnons consistent with previous neutron scattering results for bulk single crystals. As the thickness is reduced, these ferromagnetic spin excitations renormalize to lower energies along the out-of-plane direction while retaining their dispersion in the in-plane direction. This thickness dependence is captured by simple Heisenberg model calculations accounting for the confinement in the out-of-plane direction through the loss of Fe bonds. Our findings highlight the effects of mesoscopic scaling on spin dynamics and identify thickness as a knob for fine tuning and controlling magnetic properties.

16.
Sensors (Basel) ; 20(18)2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32932851

RESUMEN

The ability to estimate the current locations of mobile robots that move in a limited workspace and perform tasks is fundamental in robotic services. However, even if the robot is given a map of the workspace, it is not easy to quickly and accurately determine its own location by relying only on dead reckoning. In this paper, a new signal fluctuation matrix and a tracking algorithm that combines the extended Viterbi algorithm and odometer information are proposed to improve the accuracy of robot location tracking. In addition, to collect high-quality learning data, we introduce a fusion method called simultaneous localization and mapping and Wi-Fi fingerprinting techniques. The results of the experiments conducted in an office environment confirm that the proposed methods provide accurate and efficient tracking results. We hope that the proposed methods will also be applied to different fields, such as the Internet of Things, to support real-life activities.

17.
Heliyon ; 6(6): e04260, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32613125

RESUMEN

While many business intelligence methods have been applied to predict movie box office revenue, the studies using an ensemble approach to predict box office revenue are almost nonexistent. In this study, we propose decision trees, k-nearest-neighbors (k-NN), and linear regression using ensemble methods and the prediction performance of decision trees based on random forests, bagging and boosting are compared with that of k-NN and linear regression based on bagging and boosting using the sample of 1439 movies. The results indicate that ensemble methods based on decision trees (random forests, bagging, boosting) outperform ensemble methods based on k-NN (bagging, boosting) in predicting box office at week 1, 2, 3 after release. Decision trees using ensemble methods provide better prediction performance than ensemble methods based on linear regression analysis in the box office at week 1 after release. This is explained by the results that after comparing the prediction performance between ensemble methods and non-ensemble methods. For decision tree methods, unlike the other methods, the prediction performance of ensemble methods is greater than that of non-ensemble methods. This shows that decision trees using ensemble methods provide better application effectiveness of ensemble methods than k-NN and linear regression analysis.

18.
Molecules ; 25(12)2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32580297

RESUMEN

Kirsten rat sarcoma viral oncogene homolog (KRAS)-driven colorectal cancer (CRC) is notorious to target with drugs and has shown ineffective treatment response. The seeds of Pharbitis nil, also known as morning glory, have been used as traditional medicine in East Asia. We focused on whether Pharbitis nil seeds have a suppressive effect on mutated KRAS-driven CRC as well as reserving muscle cell functions during CRC progression. Seeds of Pharbitis nil (Pharbitis semen) were separated by chromatography and the active compound of Pharbitis semen (PN) was purified by HPLC. The compound PN efficiently suppressed the proliferation of mutated KRAS-driven CRC cells and their clonogenic potentials in a concentration-dependent manner. It also induced apoptosis of SW480 human colon cancer cells and cell cycle arrest at the G2/M phase. The CRC related pathways, including RAS/ERK and AKT/mTOR, were assessed and PN reduced the phosphorylation of AKT and mTOR. Furthermore, PN preserved muscle cell proliferation and myotube formation in cancer conditioned media. In summary, PN significantly suppressed mutated KRAS-driven cell growth and reserved muscle cell function. Based on the current study, PN could be considered as a promising starting point for the development of a nature-derived drug against KRAS-mutated CRC progression.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Ipomoea nil/química , Proteínas Proto-Oncogénicas p21(ras)/genética , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Humanos , Células Musculares/efectos de los fármacos , Células Musculares/patología , Mutación/efectos de los fármacos , Semillas/química
19.
Sensors (Basel) ; 20(2)2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31936851

RESUMEN

Keeping IoT devices secure has been a major challenge recently. One of the possible solutions to secure IoT devices is to use a physically unclonable function (PUF). A PUF is a security primitive that can generate device-specific cryptographic information by extracting the features of hardware uncertainty. Because PUF instances are very difficult to replicate even by the manufacturer, the generated bit sequence can be used as cryptographic keys or as a unique identifier for the device. Regarding the implementation of PUF, the majority of PUFs introduced over the past decade are in the form of active components and have been implemented as separate chips or embedded as a part of a chip, making it difficult to use them in low-cost IoT devices due to cost and design flexibility. One approach to easily adopt PUFs in resource-constrained IoT devices is to use passive components such as resistors and capacitors (RC) that can be configured at low cost. The main feature of this RC-based PUF is that it extracts the small difference caused by charging and discharging of RC circuits and uses it as a response. In this paper, we extend the previous research and show the possibility to secure IoT devices by using the RC-based PUF.

20.
Phys Rev Lett ; 123(11): 117201, 2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31573260

RESUMEN

Through a combination of experimental measurements and theoretical modeling, we describe a strongly orbital-polarized insulating ground state in an (LaTiO_{3})_{2}/(LaCoO_{3})_{2} oxide heterostructure. X-ray absorption spectra and ab initio calculations show that an electron is transferred from the titanate to the cobaltate layers. The charge transfer, accompanied by a large octahedral distortion, induces a substantial orbital polarization in the cobaltate layer of a size unattainable via epitaxial strain alone. The asymmetry between in-plane and out-of-plane orbital occupancies in the high-spin cobaltate layer is predicted by theory and observed through x-ray linear dichroism experiments. Manipulating orbital configurations using interfacial coupling within heterostructures promises exciting ground-state engineering for realizing new emergent electronic phases in metal oxide superlattices.

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