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1.
Sci Rep ; 13(1): 20861, 2023 11 27.
Article in English | MEDLINE | ID: mdl-38012168

ABSTRACT

Heart rhythm complexity (HRC), a subtype of heart rate variability (HRV), is an important tool to investigate cardiovascular disease. In this study, we aimed to analyze serial changes in HRV and HRC metrics in patients with inferior ST-elevation myocardial infarction (STEMI) within 1 year postinfarct and explore the association between HRC and postinfarct left ventricular (LV) systolic impairment. We prospectively enrolled 33 inferior STEMI patients and 74 control subjects and analyzed traditional linear HRV and HRC metrics in both groups, including detrended fluctuation analysis (DFA) and multiscale entropy (MSE). We also analyzed follow-up postinfarct echocardiography for 1 year. The STEMI group had significantly lower standard deviation of RR interval (SDNN), and DFAα2 within 7 days postinfarct (acute stage) comparing to control subjects. LF power was consistently higher in STEMI group during follow up. The MSE scale 5 was higher at acute stage comparing to control subjects and had a trend of decrease during 1-year postinfarct. The MSE area under scale 1-5 showed persistently lower than control subjects and progressively decreased during 1-year postinfarct. To predict long-term postinfarct LV systolic impairment, the slope between MSE scale 1 to 5 (slope 1-5) had the best predictive value. MSE slope 1-5 also increased the predictive ability of the linear HRV metrics in both the net reclassification index and integrated discrimination index models. In conclusion, HRC and LV contractility decreased 1 year postinfarct in inferior STEMI patients, and MSE slope 1-5 was a good predictor of postinfarct LV systolic impairment.


Subject(s)
ST Elevation Myocardial Infarction , Humans , Echocardiography , Cardiovascular Physiological Phenomena , Ventricular Function, Left , Heart Rate/physiology
2.
Inorg Chem ; 62(49): 19930-19936, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-37990884

ABSTRACT

Organic-inorganic hybrid perovskites (OIHPs) have been emerging as a hot research topic due to their potential applications in energy storage, semiconductors, and electronic devices. Herein, we systematically investigated the synthesis and phase transition behaviors of the enantiomeric OIHPs, (R) and (S)-N,N-dimethyl-3-fluoropyrrolidinium cadmium bromide ([DMFP][CdBr3]), and the hybrid trigonal structure [DMFP]3 (CdBr3)(CdBr4). The enantiomers have a mirror-symmetric structure and enhanced solid-state phase transition points of 417 and 443 K, in contrast to the nonfluorinated parent compound, N,N-dimethyl-pyrrolidinium cadmium bromide ([DMP][CdBr3], 385 K). Moreover, racemic H/F substitution on the pyrrolidinium cations leads to the formation of a trigonal compound, showing above-room-temperature structural phase transition and dominant ferroelasticity. This work discovers chiral enantiomeric OIHPs through H/F substitution, demonstrating a useful chemical synthesis strategy for exploring novel phase transition materials.

3.
Phys Rev Lett ; 130(17): 176802, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37172248

ABSTRACT

The mechanism on ferroelectric phase transitions is mainly attributed to the displacive and/or order-disorder transition of internal components since the discovery of the ferroelectricity in 1920, rather than the breaking and recombination of chemical bonds. Here, we demonstrate how to utilize the chemical bond rearrangement in a diarylethene-based crystal to realize the light-driven mm2F1-type ferroelectric phase transition. Such a photoinduced phase transition is entirely driven by switchable covalent bonds with breaking and reformation, enabling the reversible light-controllable ferroelectric polarization switching, dielectric and nonlinear optical bistability. Moreover, light as quantized energy can achieve contactless, nondestructive, and remote-control operations. This work proposes a new mechanism of ferroelectric phase transition, and highlights the significance of photochromic molecules in designing new ferroelectrics for photocontrol data storage and sensing.

4.
JACS Au ; 3(2): 603-609, 2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36873683

ABSTRACT

Organic single-component ferroelectrics are highly desirable for their low molecular mass, light weight, low processing temperature, and excellent film-forming properties. Organosilicon materials with a strong film-forming ability, weather resistance, nontoxicity, odorlessness, and physiological inertia are very suitable for device applications related to the human body. However, the discovery of high-T c organic single-component ferroelectrics has been very scarce, and the organosilicon ones even less so. Here, we used a chemical design strategy of H/F substitution to successfully synthesize a single-component organosilicon ferroelectric tetrakis(4-fluorophenylethynyl)silane (TFPES). Systematic characterizations and theory calculations revealed that, compared with the parent nonferroelectric tetrakis(phenylethynyl)silane, fluorination caused slight modifications of the lattice environment and intermolecular interactions, inducing a 4/mmmFmm2-type ferroelectric phase transition at a high T c of 475 K in TFPES. To our knowledge, this T c should be the highest among the reported organic single-component ferroelectrics, providing a wide operating temperature range for ferroelectrics. Moreover, fluorination also brought about a significant improvement in the piezoelectric performance. Combined with excellent film properties, the discovery of TFPES provides an efficient path for designing ferroelectrics suitable for biomedical and flexible electronic devices.

5.
Korean J Radiol ; 24(4): 349-361, 2023 04.
Article in English | MEDLINE | ID: mdl-36907594

ABSTRACT

OBJECTIVE: To quantitatively assess the pulmonary vasculature using non-contrast computed tomography (CT) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) pre- and post-treatment and correlate CT-based parameters with right heart catheterization (RHC) hemodynamic and clinical parameters. MATERIALS AND METHODS: A total of 30 patients with CTEPH (mean age, 57.9 years; 53% female) who received multimodal treatment, including riociguat for ≥ 16 weeks with or without balloon pulmonary angioplasty and underwent both non-contrast CT for pulmonary vasculature analysis and RHC pre- and post-treatment were included. The radiographic analysis included subpleural perfusion parameters, including blood volume in small vessels with a cross-sectional area ≤ 5 mm² (BV5) and total blood vessel volume (TBV) in the lungs. The RHC parameters included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), and cardiac index (CI). Clinical parameters included the World Health Organization (WHO) functional class and 6-minute walking distance (6MWD). RESULTS: The number, area, and density of the subpleural small vessels increased after treatment by 35.7% (P < 0.001), 13.3% (P = 0.028), and 39.3% (P < 0.001), respectively. The blood volume shifted from larger to smaller vessels, as indicated by an 11.3% increase in the BV5/TBV ratio (P = 0.042). The BV5/TBV ratio was negatively correlated with PVR (r = -0.26; P = 0.035) and positively correlated with CI (r = 0.33; P = 0.009). The percent change across treatment in the BV5/TBV ratio correlated with the percent change in mPAP (r = -0.56; P = 0.001), PVR (r = -0.64; P < 0.001), and CI (r = 0.28; P = 0.049). Furthermore, the BV5/TBV ratio was inversely associated with the WHO functional classes I-IV (P = 0.004) and positively associated with 6MWD (P = 0.013). CONCLUSION: Non-contrast CT measures could quantitatively assess changes in the pulmonary vasculature in response to treatment and were correlated with hemodynamic and clinical parameters.


Subject(s)
Angioplasty, Balloon , Hypertension, Pulmonary , Pulmonary Embolism , Humans , Female , Middle Aged , Male , Hypertension, Pulmonary/diagnostic imaging , Hypertension, Pulmonary/therapy , Hypertension, Pulmonary/complications , Pulmonary Embolism/complications , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/therapy , Lung , Tomography, X-Ray Computed/methods , Hemodynamics , Angioplasty, Balloon/methods , Chronic Disease , Pulmonary Artery
6.
J Am Chem Soc ; 144(42): 19559-19566, 2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36222219

ABSTRACT

Chirality exists everywhere from natural amino acids to particle physics. The introduction of point chirality has recently been shown to be an efficient strategy for the construction of molecular ferroelectrics. In contrast to point chirality, however, axial chirality is rarely used to design ferroelectrics so far. Here, based on optically active 1,1'-bi-2-naphthol (BINOL), which has been applied extensively as a versatile chiral reagent in asymmetric catalysis, chiral recognition, and optics, we successfully design a pair of axial-chiral BINOL multiferroics, (R)-BINOL-DIPASi and (S)-BINOL-DIPASi. They experience a 2F1-type full ferroelectric/ferroelastic phase transition at a high temperature of 362 and 363 K, respectively. Piezoelectric force microscopy and polarization-voltage hysteresis loops demonstrate their ferroelectric domains and domain switching, and polarized light microscopy visualizes the evolution of stripe-shaped ferroelastic domains. The axial-chiral BINOL building block promotes the generation of the polar structure and ferroelectricity, and the organosilicon component increases the rotational energy barrier and thus the phase transition temperature. This work presents the first axial-chiral high-temperature multiferroic crystals, offering an efficient path for designing molecular multiferroics through the introduction of axial chirality.

7.
Chem Commun (Camb) ; 58(74): 10361-10364, 2022 Sep 15.
Article in English | MEDLINE | ID: mdl-36017633

ABSTRACT

Single component organic ferroelectrics of spirooxazacamphorsultam derivatives, 1-SSR and 1-RRS, exhibit well-defined ferroelectricity (Ps = 2.2 µC cm-2) and piezoelectricity (d33 = 10 pC N-1) below their melting point. More importantly, they possess a low acoustic impedance value of 2.7 × 106 kg s-1 m-2, which is well-matched with body tissues.


Subject(s)
Acoustics
8.
Inorg Chem ; 61(15): 5836-5843, 2022 Apr 18.
Article in English | MEDLINE | ID: mdl-35388698

ABSTRACT

Hybrid organic-inorganic perovskites (HOIPs) have emerged as multifunctional materials with remarkable optical and electronic properties. In particular, 2D-layered lead iodide-based HOIPs possess great practical application potential in the photoelectric field. In this work, we report H/F substitution-induced 1D-to-2D increment of lead iodide HOIPs. The enantiomeric HOIPs, S- and R-FPPbI3 (FP = 3-fluoropyrrolidinium), were achieved by monofluoride substitution on the spacer cations of the parent HOIP, PyPbI3 (Py = pyrrolidinium), showing mirror image structural relationship and reversible solid-state phase transition. A 2D-layered HOIP, (DFP)2PbI4 (DFP = 3,3-difluoropyrrolidinium), was achieved with a low band gap of 2.09 eV through difluoride substitution, thanks to the expansion of the Pb-I network from 1D to 2D. This work highlights the exploration of 1D chiral and 2D-layered HOIP materials with reversible phase transitions through H/F substitution strategies.


Subject(s)
Iodides , Cations , Electronics
9.
Chem Commun (Camb) ; 58(18): 3059-3062, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-35166294

ABSTRACT

A three-dimensional cyano-bridged double perovskite ferroelastic [(CH3)3NCH2F]2[KFe(CN)6] was constructed by introducing unprecedented switchable C-F-K coordination bonds. H/F substitution not only preserves the basic structure of the parent [(CH3)4N]2[KFe(CN)6] but also affords an m3̄mF2/m-type ferroelastic phase transition.

10.
Toxics ; 9(12)2021 Dec 12.
Article in English | MEDLINE | ID: mdl-34941785

ABSTRACT

Phthalate exposure is associated with cardiovascular risk. Among the various phthalates, di-(2-ethylhexyl) phthalate (DEHP) is a deleterious plasticizer in our daily lives. This study investigated the association between DEHP exposure and the alteration of heart rate variability (HRV). During 2017-2019, we recruited 974 young adults to investigate the effects of living environments and dietary habits on cardiometabolic disorders in Taiwan. We quantitatively analyzed urinary metabolites of DHEP. A continuous electrocardiogram was recorded to obtain a 5-min ECG. Time-domain and frequency-domain HRV analyses were performed. Multiple linear regression showed that urinary oxidized DEHP metabolites MEHHP and MEOHP were associated with decreased HRV after controlling for associated cardiovascular risk factors. A higher MEHHP level was associated with a lower triangular interpolation of NN interval histogram (TINN), very low frequency (VLF), and low frequency/high frequency (LF/HF) ratio. A higher MEOHP level was associated with a decreased LF/HF ratio. In addition, trend analysis showed that higher MEHHP and MEOHP quantiles were significantly associated with a decreased LF/HF ratio. DEHP is a potentially harmful and invisible chemical. The urinary DEHP metabolites MEHHP and MEOHP are associated with decreased HRV, indicating an adverse effect on autonomic balance in young adults in Taiwan.

11.
Entropy (Basel) ; 23(6)2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34203737

ABSTRACT

Pulmonary hypertension (PH) is a fatal disease-even with state-of-the-art medical treatment. Non-invasive clinical tools for risk stratification are still lacking. The aim of this study was to investigate the clinical utility of heart rhythm complexity in risk stratification for PH patients. We prospectively enrolled 54 PH patients, including 20 high-risk patients (group A; defined as WHO functional class IV or class III with severely compromised hemodynamics), and 34 low-risk patients (group B). Both linear and non-linear heart rate variability (HRV) variables, including detrended fluctuation analysis (DFA) and multiscale entropy (MSE), were analyzed. In linear and non-linear HRV analysis, low frequency and high frequency ratio, DFAα1, MSE slope 5, scale 5, and area 6-20 were significantly lower in group A. Among all HRV variables, MSE scale 5 (AUC: 0.758) had the best predictive power to discriminate the two groups. In multivariable analysis, MSE scale 5 (p = 0.010) was the only significantly predictor of severe PH in all HRV variables. In conclusion, the patients with severe PH had worse heart rhythm complexity. MSE parameters, especially scale 5, can help to identify high-risk PH patients.

12.
Shanghai Kou Qiang Yi Xue ; 11(1): 56-9, 2002 Mar.
Article in Chinese | MEDLINE | ID: mdl-14983340

ABSTRACT

OBJECTIVE: Investigating the conditions of oral health in professors, promoting the prophylactico-therapeutic standard of dental diseases in the university. METHODS: The table and the standard on oral health survey authorized by WHO were adopted, conditions of dental and periodontal diseases in 965 of professors of Tsinghua university was standardly investigated. RESULTS: (1) Caries prevalence was 51.92%, caries average 1.66+/-0.31, caries activity teeth constituted 22.94% in DMFT, caries missing teeth constituted 25.56%, caries filled teeth constituted 51.50%. (2) Gingival bleeding average zones were 1.26+/-0.21, incidence 48.71%; shallow periodontal pocket average zones were 0.28+/-0.08, incidence 15.34%; deep periodontal pocket average zones were 0.10+/-0.08, incidence 6.84%. (3) Wedge shaped defect teeth average of the persons was 1.85+/-0.54, incidence 30.00% . CONCLUSION: Conditions of caries were better than the data throughout the country, the incidence of periodontal diseases were higher, wedge shaped defect had been decaying teeth of middle and old aged professors.

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