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1.
Psychiatry Investig ; 20(10): 904-911, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37899213

ABSTRACT

OBJECTIVE: Providing inpatient nursing care inevitably involves night shift work. However, night shift work nurses often face psychiatric health problems such as burnout. If night shift work is an essential work type for nurses, it is necessary to select personnel suitable for night shift work or establish improvement measures such as psychiatric intervention through psychiatric evaluation. The objective of this study was to identify factors that could be interventional among factors affecting burnout in shift-working nurses. METHODS: A total of 231 night shift female nurses participated in this study. A questionnaire survey was given to assess their general characteristics. To assess burnout, the Maslach Burnout Inventory-General Survey Korean version was adopted. In addition, several mental health scales were used to identify individual psychological characteristics. To identify variables associated with the presence of burnout, odds ratios were calculated using a logistic regression model taking three dimensions of burnout as a dependent variable after adjusting for psychological and occupational factors. RESULTS: High resilience was a significant preventive factor in the three dimensions of burnout. Regarding occupational factor, the longer the duration of employment, the higher depersonalization, but the professional efficacy was good. CONCLUSION: Our results indicate that resilience and social support could be prevention factors for burnout. This study is meaningful in examining items that require active intervention and support for burnout targeting night shift nurses who are indispensable for patient care.

2.
Nat Commun ; 14(1): 2936, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37217490

ABSTRACT

The significant discrepancy observed between the predicted and experimental switching fields in correlated insulators under a DC electric field far-from-equilibrium necessitates a reevaluation of current microscopic understanding. Here we show that an electron avalanche can occur in the bulk limit of such insulators at arbitrarily small electric field by introducing a generic model of electrons coupled to an inelastic medium of phonons. The quantum avalanche arises by the generation of a ladder of in-gap states, created by a multi-phonon emission process. Hot-phonons in the avalanche trigger a premature and partial collapse of the correlated gap. The phonon spectrum dictates the existence of two-stage versus single-stage switching events which we associate with charge-density-wave and Mott resistive phase transitions, respectively. The behavior of electron and phonon temperatures, as well as the temperature dependence of the threshold fields, demonstrates how a crossover between the thermal and quantum switching scenarios emerges within a unified framework of the quantum avalanche.

3.
Clin Lab ; 69(1)2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36649524

ABSTRACT

BACKGROUND: Nephrin is a protein in the glomerular podocyte slit diaphragm; therefore, its presence in urine implies damage to podocytes. This study aimed to determine the usefulness of nephrin as a biomarker in maternal urine to predict preeclampsia (PE). METHODS: This prospective study included pregnant women admitted for delivery at Seoul National University Bundang Hospital from March 2019 to May 2020. Patients who had been diagnosed with PE were included, and patients without a history of underlying diseases were recruited for the control group. Pertinent clinical data were collected. Urine samples were obtained, and nephrin signaling was detected through test strips using a lateral flow assay. The point-of-care test results were compared between patients with PE and without (control group), using the exact concentration of nephrin by enzyme-linked immunosorbent assay. RESULTS: Clinical characteristics - maternal age, parity, proportion of twin pregnancies, height, weight, and cesarean delivery rate - were comparable between the PE and control groups. Nephrin signals were classified into four groups. In the PE group, signals 0, 1, 2, and 3 were found in 18.4% (9/49), 44.9% (22/49), 24.5% (12/49), and 12.2% (6/49) of participants, respectively. Results were significantly different in the control group, in which 84.3% (43/51) were found to have signal 0 (p < 0.001). CONCLUSIONS: Nephrin signaling in maternal urine could be a noninvasive and useful test for early detection of severity of PE.


Subject(s)
Podocytes , Pre-Eclampsia , Humans , Pregnancy , Female , Pre-Eclampsia/diagnosis , Prospective Studies , Membrane Proteins/metabolism , Podocytes/metabolism
4.
Ann Occup Environ Med ; 34: e33, 2022.
Article in English | MEDLINE | ID: mdl-36544884

ABSTRACT

Background: Circadian rhythm disturbance caused by shift work has adverse effects on the metabolic homeostasis of the liver. Disruption of the metabolic homeostasis of the liver causes fat accumulation in the liver. The aim of this study was to investigate the correlation between shift work and non-alcoholic fatty liver disease (NAFLD) among male workers in the steel manufacturing industry of Korea. Methods: Based on medical examination data collected in June 2020, 2,511 male subjects from one steel manufacturing company in Korea were selected in total. NAFLD was evaluated using abdominal ultrasound, which was performed by two experienced radiologists. The multinomial logistic regression analysis was performed by adjusting for age, physical activity, smoking history, alcohol consumption, body mass index, waist circumference, blood pressure, blood glucose, lipidemia, liver function test, employment duration, and hepatotoxic materials exposure status. Results: Compared to daytime workers, the odds ratio (OR) of moderate-severe NAFLD in shift workers was 1.449 (95% confidence interval [CI], 1.028-2.043). Compared to daytime workers, the ORs of moderate-severe NAFLD were significantly higher for the group that engaged in total shift work for more than 20 years (OR, 2.285; 95% CI, 1.051-4.970), the group that was not allowed to sleep during night shift work (OR, 1.463; 95% CI, 1.030-2.078), and the group that consumed food during night shift work (OR, 1.580; 95% CI, 1.093-2.284). Conclusions: There was a correlation between shift work and moderate-severe NAFLD in male steel manufacturing workers. There will be a need for more research related to the correlation of shift work with steatohepatitis and cirrhosis in the future.

5.
Ann Occup Environ Med ; 33: e32, 2021.
Article in English | MEDLINE | ID: mdl-34868602

ABSTRACT

BACKGROUND: The aim of this study was to investigate the relationship between occupational exposure to various hazards and hospital admission due to endocrine diseases in Korean male firefighters. METHODS: From 2000 to 2008, former and current male firefighters registered in the Korean National Emergency Management Agency were investigated based on their hospitalized health insurance admission data for the same period. Admission data for endocrine, nutritional, and metabolic diseases were obtained from the Korean National Health Insurance Service database. Standardized admission ratio (SAR) with reference to the general population of Korean men was analyzed. RESULTS: SAR for firefighters with endocrine, nutritional, and metabolic diseases was 0.56 (95% confidence interval [CI]: 0.49-0.65), which was significantly less than that of the general population of Korean men. For those with endocrine, nutritional, and metabolic diseases, SARs for those with a history of fire suppression tasks and those without experience of fire suppression tasks were 0.58 (95% CI: 0.49-0.68) and 0.53 (95% CI: 0.40-0.70), respectively. CONCLUSIONS: The admission rate of Korean male firefighters due to endocrine, nutritional and metabolic diseases was significantly lower than that of the general Korean men population, the hazardous potential of endocrine disruptors remains an open question. Further studies of firefighters with longer follow-up are needed.

6.
Nano Lett ; 20(9): 6299-6305, 2020 Sep 09.
Article in English | MEDLINE | ID: mdl-32787162

ABSTRACT

We investigate electronic states of Se-substituted 1T-TaS2 by scanning tunneling microscopy/spectroscopy (STM/STS), where superconductivity emerges from the unique Mott-charge-density-wave (Mott-CDW) state. Spatially resolved STS measurements reveal that a pseudogap replaces the Mott gap with the CDW gaps intact. The pseudogap has little correlation with the unit-cell-to-unit-cell variation in the local Se concentration but appears globally. The correlation length of the local density of states (LDOS) is substantially enhanced at the Fermi energy and decays rapidly at high energies. Furthermore, the statistical analysis of LDOS indicates the weak multifractal behavior of the wave functions. These findings suggest a correlated metallic state induced by disorder and provide a new insight into the emerging superconductivity in two-dimensional materials.

7.
Oxid Med Cell Longev ; 2019: 9296439, 2019.
Article in English | MEDLINE | ID: mdl-31019654

ABSTRACT

Cancer stem cells (CSCs) are known to mediate metastasis and recurrence and are therefore a promising therapeutic target. In this study, we found that dihydrotanshinone (DHTS) inhibits CSC formation. DHTS inhibited mammosphere formation in a dose-dependent manner and showed significant tumor growth inhibition in a xenograft model. This compound reduced the CD44high/CD24low- and aldehyde dehydrogenase- (ALDH-) expressing cell population and the self-renewal-related genes Nanog, SOX2, OCT4, C-Myc, and CD44. DHTS induced NOX5 activation by increasing calcium, and NOX5 activation induced reactive oxygen species (ROS) production. ROS production reduced the nuclear phosphorylation levels of Stat3 and secreted IL-6 levels in the mammospheres. DHTS deregulated the dynamic equilibrium from non-stem cancer cells to CSCs by dephosphorylating Stat3 and decreasing IL-6 secretion and inhibiting CSC formation. These novel findings showed that DHTS-induced ROS deregulated the Stat3/IL-6 pathway and induced CSC death. NOX5 activation by DHTS inhibits CSC formation through ROS/Stat3/IL-6 signaling, and DHTS may be a promising potential therapeutic agent against breast CSCs.


Subject(s)
Breast Neoplasms/enzymology , Drugs, Chinese Herbal/pharmacology , NADPH Oxidase 5/metabolism , Neoplastic Stem Cells/enzymology , Reactive Oxygen Species/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects , Acetylcysteine/pharmacology , Animals , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Calcium/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Self Renewal/drug effects , Enzyme Activation/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Interleukin-6/metabolism , Mice, Nude , NADPH Oxidase 2/metabolism , NADPH Oxidase 5/genetics , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , Salvia miltiorrhiza , Spheroids, Cellular/drug effects , Spheroids, Cellular/metabolism , Spheroids, Cellular/pathology , Transcription, Genetic/drug effects , Xenograft Model Antitumor Assays
8.
Front Immunol ; 10: 209, 2019.
Article in English | MEDLINE | ID: mdl-30800133

ABSTRACT

IL-17 produced by Th17 cells has been implicated in the pathogenesis of rheumatoid arthritis (RA). It is important to prevent the differentiation of Th17 cells in RA. Homodimeric soluble γc (sγc) impairs IL-2 signaling and enhances Th17 differentiation. Thus, we aimed to block the functions of sγc by inhibiting the formation of homodimeric sγc. The homodimeric form of sγc was strikingly disturbed by sγc-binding DNA aptamer. Moreover, the aptamer effectively inhibited Th17 cell differentiation and restored IL-2 and IL-15 signaling impaired by sγc with evidences of increased survival of T cells. sγc was highly expressed in SF of RA patients and increased in established CIA mice. The therapeutic effect of PEG-aptamer was tested in CIA model and its treatment alleviated arthritis pathogenesis with impaired differentiation of pathogenic Th17, NKT1, and NKT17 cells in inflamed joint. Homodimeric sγc has pathogenic roles to exacerbate RA progression with differentiation of local Th17, NKT1, and NKT17 cells. Therefore, sγc is suggested as target of a therapeutic strategy for RA.


Subject(s)
Aptamers, Nucleotide/pharmacology , Arthritis, Experimental/chemically induced , Arthritis, Rheumatoid/immunology , Chitinase-3-Like Protein 1/pharmacology , Interleukin Receptor Common gamma Subunit/antagonists & inhibitors , Th17 Cells/immunology , Aged , Animals , Aptamers, Nucleotide/chemistry , Cell Differentiation/drug effects , Dimerization , Female , HEK293 Cells , Humans , Inflammation/immunology , Interleukin Receptor Common gamma Subunit/chemistry , Interleukin-15/metabolism , Interleukin-2/metabolism , Mice , Mice, Inbred DBA , Middle Aged , Natural Killer T-Cells/immunology , SELEX Aptamer Technique/methods , Transfection
9.
Sci Rep ; 8(1): 15598, 2018 Oct 22.
Article in English | MEDLINE | ID: mdl-30348971

ABSTRACT

Linepipe steels complexly consisted of low-temperature transformation microstructures of bainitic ferrite, granular bainite, and acicular ferrite (AF) as well as polygonal ferrite (PF) which individually affect the Bauschinger effect occurring during the pipe-forming. In this study, microscopic analyses of electron back-scattered diffraction (EBSD) coupled with tension-compression and interrupted bending tests were performed for verification of the Bauschinger effect of AF and PF working as major microstructures in single-phase- and two-phase-rolled API X80 steels, respectively. With respect to microstructural effects on Bauschinger effect, the reduction in mobile dislocation density during the flattening was smaller in the AF than in the PF. However, the dislocation pile-up at low-angle substructures and high-angle grain boundaries was more frequently observed, thereby leading to the higher back stress and Bauschinger effect in the AF. Boundary kernel average misorientation (KAM) profile played a critical role in determining the Bauschinger effect because they were closely related with the back stress. Thus, the Bauschinger effect was higher in the single-phase-rolled steel than in the two-phase-rolled steel. The present ex-situ interrupted bending methods coupled with EBSD analyses are outstanding ones for the detailed explanation of Bauschinger effect and provide an important idea for the yield strength designs of linepipe steels.

10.
Nano Lett ; 18(9): 5432-5438, 2018 09 12.
Article in English | MEDLINE | ID: mdl-30063833

ABSTRACT

Emergent phenomena driven by electronic reconstructions in oxide heterostructures have been intensively discussed. However, the role of these phenomena in shaping the electronic properties in van der Waals heterointerfaces has hitherto not been established. By reducing the material thickness and forming a heterointerface, we find two types of charge-ordering transitions in monolayer VSe2 on graphene substrates. Angle-resolved photoemission spectroscopy (ARPES) uncovers that Fermi-surface nesting becomes perfect in ML VSe2. Renormalization-group analysis confirms that imperfect nesting in three dimensions universally flows into perfect nesting in two dimensions. As a result, the charge-density wave-transition temperature is dramatically enhanced to a value of 350 K compared to the 105 K in bulk VSe2. More interestingly, ARPES and scanning tunneling microscopy measurements confirm an unexpected metal-insulator transition at 135 K that is driven by lattice distortions. The heterointerface plays an important role in driving this novel metal-insulator transition in the family of monolayer transition-metal dichalcogenides.

11.
JACC Cardiovasc Imaging ; 11(12): 1810-1819, 2018 12.
Article in English | MEDLINE | ID: mdl-29454763

ABSTRACT

OBJECTIVES: This study sought to measure early strut coverage in patients receiving drug-eluting stents (DESs) and to explore the feasibility of short-term dual antiplatelet therapy (DAPT) based on the degree of early strut coverage. BACKGROUND: Data for early strut coverage in patients receiving new-generation DESs, and its implications for DAPT continuation were limited. METHODS: A randomized, multicenter trial was conducted in 894 patients treated with DESs. Patients were randomly assigned to everolimus-eluting stent (EES) (n = 444) or biolimus-eluting stent (BES) (n = 450) groups and optical coherence tomography (OCT)-guided (n = 445) or angiography-guided (n = 449) implantation groups using a 2-by-2 factorial design. Early strut coverage was measured as the percentage of uncovered struts on 3-month follow-up OCT examination. The primary outcome was the difference in early strut coverage between EES and BES groups and between OCT- and angiography-guided implantation groups. The secondary outcome was a composite of cardiac death, myocardial infarction, stent thrombosis, and major bleeding during the first 12 months post-procedure in patients receiving 3-month DAPT based on the presence of early strut coverage (≤6% uncovered) on 3-month follow-up OCT. RESULTS: Three-month follow-up OCT data were acquired for 779 patients (87.1%). The median percentage of uncovered struts at 3 months was 8.9% and 8.2% in the EES and BES groups, respectively (p = 0.69) and was lower in the OCT-guided group (7.5%) than in the angiography-guided group (9.9%; p = 0.009). Favorable early strut coverage (≤6% uncovered strut) was observed in 320 of 779 patients (41.1%). At 12 months, the composite event rarely occurred in the 3-month (0.3%) or 12-month (0.2%) DAPT groups (p = 0.80). CONCLUSIONS: OCT-guided DES implantation improved early strut coverage compared with angiography-guided DES implantation, with no difference in strut coverage between EES and BES groups. Short-term DAPT may be feasible in selected patients with favorable early strut coverage (Determination of the Duration of the Dual Antiplatelet Therapy by the Degree of the Coverage of The Struts on Optical Coherence Tomography From the Randomized Comparison Between Everolimus-eluting Stents Versus Biolimus A9-eluting Stents [DETECT-OCT]; NCT01752894).


Subject(s)
Coronary Artery Disease/therapy , Drug-Eluting Stents , Percutaneous Coronary Intervention/instrumentation , Platelet Aggregation Inhibitors/administration & dosage , Aged , Cardiovascular Agents/administration & dosage , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/mortality , Coronary Thrombosis/mortality , Drug Therapy, Combination , Everolimus/administration & dosage , Feasibility Studies , Female , Humans , Male , Middle Aged , Myocardial Infarction/mortality , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/mortality , Platelet Aggregation Inhibitors/adverse effects , Prosthesis Design , Republic of Korea , Risk Factors , Sirolimus/administration & dosage , Sirolimus/analogs & derivatives , Stroke/mortality , Time Factors , Tomography, Optical Coherence , Treatment Outcome
12.
J Cardiovasc Imaging ; 26(4): 217-225, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30607389

ABSTRACT

BACKGROUND: In patients with acute heart failure (AHF), diastolic dysfunction, especially pseudonormal (PN) or restrictive filling pattern (RFP) of left ventricle (LV), is considered to be implicated in a poor prognosis. However, prognostic significance of diastolic dysfunction in patients with ischemic heart disease (IHD) has been rarely investigated in Korea. METHODS: We enrolled 138 patients with IHD presenting as AHF and sinus rhythm during echocardiographic study. Diastolic dysfunction of LV was graded as ≥ 2 (group 1) or 1 (group 2) according to usual algorithm using E/A ratio and deceleration time of mitral inflow, E'/A' ratio of tissue Doppler echocardiography and left atrial size. RESULTS: Patients in group 1 showed higher 2-year mortality rate (36.2% ± 6.7%) than those in group 2 (13.6% ± 4.5%; p = 0.008). Two-year mortality rate of patient with LV ejection fraction (LVEF) < 40% (26.8% ± 6.0%) was not different from those with LVEF 40%-49% (28.0% ± 8.0%) or ≥ 50% (13.7% ± 7.4%; p = 0.442). On univariate analysis, PN or RFP of LV, higher stage of chronic kidney disease (CKD) and higher New York Heart Association (NYHA) functional class were poor prognostic factors, but LVEF or older age ≥ 75 years did not predict 2-year mortality. On multivariate analysis, PN or RFP of LV (hazard ratio [HR], 2.52; 95% confidence interval [CI], 1.09-5.84; p = 0.031), higher stage of CKD (HR, 1.57; 95% CI, 1.14-2.17; p = 0.006) and higher NYHA functional class (HR, 1.81; 95% CI, 1.11-2.94; p = 0.017) were still significant prognostic factors for 2-year mortality. CONCLUSIONS: PN or RFP of LV was a more useful prognostic factor for long-term mortality than LVEF in patients with IHD presenting as AHF.

13.
Nat Mater ; 16(11): 1096-1099, 2017 11.
Article in English | MEDLINE | ID: mdl-28805826

ABSTRACT

Ohm's law is a fundamental paradigm in the electrical transport of metals. Any transport signatures violating Ohm's law would give an indisputable fingerprint for a novel metallic state. Here, we uncover the breakdown of Ohm's law owing to a topological structure of the chiral anomaly in the Weyl metal phase. We observe nonlinear I-V characteristics in Bi0.96Sb0.04 single crystals in the diffusive limit, which occurs only for a magnetic-field-aligned electric field (E∥B). The Boltzmann transport theory with the charge pumping effect reveals the topological-in-origin nonlinear conductivity, and it leads to a universal scaling function of the longitudinal magnetoconductivity, which completely describes our experimental results. As a hallmark of Weyl metals, the nonlinear conductivity provides a venue for nonlinear electronics, optical applications, and the development of a topological Fermi-liquid theory beyond the Landau Fermi-liquid theory.

14.
Case Rep Ophthalmol ; 7(2): 290-5, 2016.
Article in English | MEDLINE | ID: mdl-27462257

ABSTRACT

PURPOSE: To report a new technique using tram-track suture for pupillary capture of a scleral fixated posterior chamber intraocular lens (PC-IOL) to reposition the tilted IOL. METHODS: In this prospective interventional case series, we describe a tram-track suture for pupillary capture of a scleral fixated PC-IOL. A long straight needle with double-armed 10-0 polypropylene is passed behind the iris and just above the optic portion (tilted forward) of the IOL. The other straight needle with double-armed 10-0 polypropylene is passed just below the optic portion (tilted backward) of the IOL. After the IOL is repositioned properly, the polypropylene sutures are gently pulled and tied. RESULTS: Four eyes of 4 patients underwent tram-track suture for pupillary capture of a scleral fixated PC-IOL. No intra- or postoperative complications were noted, and no pupillary captures were detected during the follow-up period. CONCLUSIONS: The tram-track suture technique provides good centration and stability of a PC-IOL. This technique is an easy and effective way to reposition pupillary capture of an IOL. Further, it is also minimally invasive as it maintains a closed system.

15.
Korean Circ J ; 46(3): 432, 2016 May.
Article in English | MEDLINE | ID: mdl-27275185

ABSTRACT

[This corrects the article on p. 169 in vol. 46, PMID: 27014347.].

16.
Korean Circ J ; 46(2): 169-78, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27014347

ABSTRACT

BACKGROUND AND OBJECTIVES: A cardiologist's evaluation of psychiatric symptoms in patients with chest pain is rare. This study aimed to determine the psychiatric characteristics of patients with and without coronary artery disease (CAD) and explore their relationship with the intensity of chest pain. SUBJECTS AND METHODS: Out of 139 consecutive patients referred to the cardiology outpatient department, 31 with atypical chest pain (heartburn, acid regurgitation, dyspnea, and palpitation) were excluded and 108 were enrolled for the present study. The enrolled patients underwent complete numerical rating scale of chest pain and the symptom checklist for minor psychiatric disorders at the time of first outpatient visit. The non-CAD group consisted of patients with a normal stress test, coronary computed tomography angiogram, or coronary angiogram, and the CAD group included those with an abnormal coronary angiogram. RESULTS: Nineteen patients (17.6%) were diagnosed with CAD. No differences in the psychiatric characteristics were observed between the groups. "Feeling tense", "self-reproach", and "trouble falling asleep" were more frequently observed in the non-CAD (p=0.007; p=0.046; p=0.044) group. In a multiple linear regression analysis with a stepwise selection, somatization without chest pain in the non-CAD group and hypochondriasis in the CAD group were linearly associated with the intensity of chest pain (ß=0.108, R(2)=0.092, p=0.004; ß= -0.525, R(2)=0.290, p=0.010). CONCLUSION: No differences in psychiatric characteristics were observed between the groups. The intensity of chest pain was linearly associated with somatization without chest pain in the non-CAD group and inversely linearly associated with hypochondriasis in the CAD group.

17.
Open Ophthalmol J ; 10: 1-4, 2016.
Article in English | MEDLINE | ID: mdl-27014379

ABSTRACT

The authors present a case of morphologic changes of drusen and drusenoid pigment epithelial detachment (DPED) after treating choroidal neovascularization (CNV) using ranibizumab in age-related macular degeneration (AMD). A 71-year-old woman has noticed mild visual acuity deterioration in the right eye for several months. She was presented with some drusen and DPED associated with CNV. This patient was given intravitreal injection of 0.5 mg of ranibizumab five times at monthly intervals for treating CNV. DPED in the temporal and drusen in the superior to macula were diminished, which continued up to 2 months. Intravitreal ranibizumab injection may have influenced with diminishment of drusen and DPED. After 2 months, CNV was recurred.

18.
Nat Commun ; 7: 10453, 2016 Jan 22.
Article in English | MEDLINE | ID: mdl-26795073

ABSTRACT

The controllability over strongly correlated electronic states promises unique electronic devices. A recent example is an optically induced ultrafast switching device based on the transition between the correlated Mott insulating state and a metallic state of a transition metal dichalcogenide 1T-TaS2. However, the electronic switching has been challenging and the nature of the transition has been veiled. Here we demonstrate the nanoscale electronic manipulation of the Mott state of 1T-TaS2. The voltage pulse from a scanning tunnelling microscope switches the insulating phase locally into a metallic phase with irregularly textured domain walls in the charge density wave order inherent to this Mott state. The metallic state is revealed as a correlated phase, which is induced by the moderate reduction of electron correlation due to the charge density wave decoherence.

19.
BMC Cardiovasc Disord ; 15: 131, 2015 Oct 19.
Article in English | MEDLINE | ID: mdl-26481213

ABSTRACT

BACKGROUND: This study analyzed PWAs in patients with high Framingham risk scores to determine whether PWA is predictive of coronary artery disease (CAD) severity and percutaneous coronary intervention (PCI) treatment. METHODS: In total, 310 patients were screened due to suspected CAD; 78 were excluded due to PCI history (32), atrial fibrillation (11), or acute myocardial infarction (35). The augmentation index (AIx) was analyzed immediately before coronary angiography. PCI was performed in 73 (31.5 %) patients. RESULTS: The mean AIx, adjusted by heart rate (AIx@75) was different for each clinical diagnosis in the PCI group (stable angina, 30.6 ± 7.7 %; silent ischemia, 30.2 ± 8.6 %; unstable angina, 38.5 ± 8.5 %; p = 0.026). The 10-year estimate of CVD risk, based on the Framingham heart score, was 25.3 ± 6.5 % and the mean AIx@75 was 31.6 ± 8.5 % in the PCI group, significantly higher than in the non-PCI group (18.8 ± 10.2 %, p < 0.001; 27.2 ± 9.0 %, p = 0.006, respectively). An inverse correlation was observed between the minimal luminal area and AIx@75 (rho = -0.559, p = 0.010, n = 20). In ROC curve analysis of multivariate logistic regression model, higher HDL, medication of hypertension, and higher body mass index were associated with non-PCI and higher AIx@75 was associated with PCI (area under the curve, 0.764; 95 % CI: 0.701 to 0.819, z = 8.005; p <0.001). CONCLUSIONS: The AIx@75 seemed to reflect the clinical severity of CAD and was associated with PCI in patients with a high Framingham risk score.


Subject(s)
Coronary Artery Disease/diagnosis , Pulse Wave Analysis , Aged , Coronary Angiography , Coronary Artery Disease/surgery , Female , Hospitals, University , Humans , Male , Middle Aged , Percutaneous Coronary Intervention , Republic of Korea , Risk Factors , Severity of Illness Index
20.
Soft Matter ; 11(40): 7932-41, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26324955

ABSTRACT

We derive an effective Maxwell-London equation for entangled polymer complexes under topological constraints, borrowing the theoretical framework from topological field theory. We find that the transverse current flux of a test polymer chain, surrounded by entangled chains, decays exponentially from its centerline position with a finite penetration depth, which is analogous to the magnetic-field decay in a superconductor (SC), referred to as the Meissner effect. Just as the mass acquirement of photons in a SC is the origin of the magnetic-field decay, the polymer obtains uncrossable intersections along the chain due to the preservation of the linking number, which restricts the deviation of the transverse polymer current in the normal direction. The underlying physics is as follows: less flexible polymers have stronger current-current correlations, giving rise to a heavier effective mass of the gauge fields and resulting in a shorter decay length. Interestingly, this picture is well incorporated within the most successful phenomenological theory of the, so called, tube model, the microscopic origins of which researchers have long pursued. The correspondence of our equation of motion to the tube model claims that the confining tube potential is a consequence of the topological constraint (linking number). The tube radius is attributed to the decay length. On increasing the effective mass (by strengthening the interaction at an uncrossable intersection or a number of intersections), the tube becomes narrower. Using this argument, the exponential decay of the chain leakage out of the tube is well understood.

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