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1.
Dement Geriatr Cogn Disord ; 53(1): 19-28, 2024.
Article in English | MEDLINE | ID: mdl-38232713

ABSTRACT

INTRODUCTION: Mental health symptoms and cognitive impairment are highly prevalent and intertwined among aging people living with HIV (PLWH). This study aimed to assess the interrelationships and strength of connections between individual mental health symptoms and cognitive impairment. We sought to identify specific symptoms linking mental health and cognitive impairment in aging PLWH. METHODS: Participants in the Sichuan Older People with HIV Infections Cohort Study (SOHICS) were recruited between November 2018 and April 2021 in China. Mental health symptoms, including depression and anxiety, were assessed by the Patient Health Questionnaire (PHQ-9) and General Anxiety Disorder-7 (GAD-7), respectively. Cognitive impairment was assessed by the Montreal Cognitive Assessment-Basic (MoCA-B). Partial correlation networks were used to depict the interrelationships between mental health symptoms and cognitive impairment, and bridge strength was used to identify specific symptoms linking mental health and cognitive impairment. RESULTS: Of the 1,587 recruited participants with a mean age of 63.0 years old, 47.0% had mild or severe cognitive impairment. Network analysis revealed that cognitive function, visual perception, and problem-solving task of the MoCA-B were negatively correlated with appetite, energy, and motor of the PHQ-9, respectively. Based on their interrelationships, problem-solving task and motor acted as bridge symptoms. CONCLUSION: Problem-solving task and motor may be potential intervention targets to reduce the overall risk of mental health symptoms and cognitive impairment. Future research could assess the feasibility and effectiveness of specific interventions designed for the two symptoms of aging PLWH.


Subject(s)
Anxiety Disorders , Cognitive Dysfunction , HIV Infections , Humans , Aged , HIV Infections/complications , HIV Infections/psychology , Mental Health , Cohort Studies , Aging , China/epidemiology
2.
BMC Public Health ; 24(1): 32, 2024 01 02.
Article in English | MEDLINE | ID: mdl-38166669

ABSTRACT

BACKGROUND: Healthy lifestyles are crucial for preventing chronic diseases. Nonetheless, approximately 90% of Chinese community residents regularly engage in at least one unhealthy lifestyle. Mobile smart devices-based health interventions (mHealth) that incorporate theoretical frameworks regarding behavioral change in interaction with the environment may provide an appealing and cost-effective approach for promoting sustainable adaptations of healthier lifestyles. We designed a randomized controlled trial (RCT) to evaluate the effectiveness of a socioecological model-guided, smart device-based, and self-management-oriented lifestyles (3SLIFE) intervention, to promote healthy lifestyles among Chinese community residents. METHODS: This two-arm, parallel, cluster-RCT with a 6-month intervention and 6-month follow-up period foresees to randomize a total of 20 communities/villages from 4 townships in a 1:1 ratio to either intervention or control. Within these communities, a total of at least 256 community residents will be enrolled. The experimental group will receive a multi-level intervention based on the socioecological model supplemented with a multi-dimensional empowerment approach. The control group will receive information only. The primary outcome is the reduction of modifiable unhealthy lifestyles at six months, including smoking, excess alcohol consumption, physical inactivity, unbalanced diet, and overweight/obesity. A reduction by one unhealthy behavior measured with the Healthy Lifestyle Index Score (HLIS) will be considered favorable. Secondary outcomes include reduction of specific unhealthy lifestyles at 3 months, 9 months, and 12 months, and mental health outcomes such as depression measured with PHQ-9, social outcomes such as social support measured with the modified Multidimensional Scale of Perceived Social Support, clinical outcomes such as obesity, and biomedical outcomes such as the development of gut microbiota. Data will be analyzed with mixed effects generalized linear models with family and link function determined by outcome distribution and accounting for clustering of participants in communities. DISCUSSION: This study will provide evidence concerning the effect of a mHealth intervention that incorporates a behavioral change theoretical framework on cultivating and maintaining healthy lifestyles in community residents. The study will provide insights into research on and application of similar mHealth intervention strategies to promote healthy lifestyles in community populations and settings. TRIAL REGISTRATION NUMBER: ChiCTR2300070575. Date of registration: April 17, 2023. https://www.chictr.org.cn/index.aspx .


Subject(s)
Self-Management , Humans , Exercise , Life Style , Obesity , Healthy Lifestyle , Randomized Controlled Trials as Topic
3.
Herz ; 49(5): 378-384, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38658408

ABSTRACT

OBJECTIVE: Many previous studies reported the relationship between lipoprotein(a) and cardiovascular disease, but the conclusions were controversial. The aim of our study was to retrospectively investigate the association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography. METHODS: We collected and compared clinical information of patients hospitalized for coronary angiography. Multivariable hierarchical logistic regression was used to evaluate the association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography. RESULTS: There were no significant differences in gender, hypertension, APOA1, smoking, hyperuricemia, obesity, acute myocardial infarction (AMI), cardiac insufficiency, family history of diabetes, or family history of hyperlipidemia among the four groups of lipoprotein(a). Elevated lipoprotein(a) does not increase the risk of hypertriglyceridemia, while elevated lipoprotein(a) increases the risk of high total cholesterol and high low-density lipoprotein cholesterol (LDL-c). Elevated lipoprotein(a) increases the risk of diabetes and premature coronary artery disease (CAD). Elevated lipoprotein(a) increases the incidence of CAD, multivessel lesions, and percutaneous coronary intervention (PCI). Multivariate logistic regression analysis further showed that elevated lipoprotein(a) increases the incidence of high total cholesterol, high LDL­c, diabetes, CAD, premature CAD, multivessel lesions, and PCI. CONCLUSION: The findings indicated that elevated lipoprotein(a) had no obvious relationship with hypertension and obesity. Elevated lipoprotein(a) increases the risk of high total cholesterol, high LDL­c, and premature CAD, and increases the occurrence and severity of coronary heart disease.


Subject(s)
Coronary Angiography , Lipoprotein(a) , Humans , Male , Lipoprotein(a)/blood , Female , Middle Aged , Comorbidity , Risk Factors , Cardiovascular Diseases/blood , Cardiovascular Diseases/diagnostic imaging , Cardiovascular Diseases/epidemiology , Biomarkers/blood , Retrospective Studies , Incidence , Aged , Coronary Artery Disease/blood , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/epidemiology , Reproducibility of Results , Sensitivity and Specificity , China/epidemiology , Risk Assessment
4.
Phys Rev Lett ; 130(19): 196801, 2023 May 12.
Article in English | MEDLINE | ID: mdl-37243636

ABSTRACT

The switchable electric polarization is usually achieved in ferroelectric materials with noncentrosymmetric structures, which opens exciting opportunities for information storage and neuromorphic computing. In another polar system of p-n junction, there exists the electric polarization at the interface due to the Fermi level misalignment. However, the resultant built-in electric field is unavailable to manipulate, thus attracting less attention for memory devices. Here, we report the interfacial polarization hysteresis (IPH) in the vertical sidewall van der Waals heterojunctions of black phosphorus and quasi-two-dimensional electron gas on SrTiO_{3}. A nonvolatile switching of electric polarization can be achieved by reconstructing the space charge region (SCR) with long-lifetime nonequilibrium carriers. The resulting electric-field controllable IPH is experimentally verified by electric hysteresis, polarization oscillation, and pyroelectric effect. Further studies confirm the transition temperature of 340 K, beyond which the IPH vanishes. The second transition is revealed with the temperature dropping below 230 K, corresponding to the sharp improvement of IPH and the freezing of SCR reconstruction. This work offers new possibilities for exploring the memory phenomena in nonferroelectric p-n heterojunctions.

5.
Prev Med ; 177: 107780, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37967619

ABSTRACT

Inconsistent correlations of screen use with physical activity (PA) and social capital (SC) in youths have been observed in existing cross-sectional studies. This study aimed to elucidate associations among variables in screen use, PA, and SC domains during COVID-19, to improve the prediction and prevention of suboptimal health status in youths. An online survey based on the nationwide COVID-19 Impact on Lifestyle Change Survey (COINLICS) was conducted in China, and 10,082 youths reported their screen use, PA, and SC in the months immediately before, during, and after the COVID-19 lockdown. Cross-sectional and longitudinal network models were used to identify associations of variables in domains of screen use with PA and SC. Effect modifications of bridges and predictors in the associations were examined. The network models suggested that individual SC was a bridge that strongly connected other types of SC, and domains of screen use and PA before lockdown, while phone use became such a bridge during and after lockdown. More PC/TV use before lockdown predicted less household-related PA during lockdown (ß = -0.142); more phone use during lockdown was a predictor for higher levels of household-related PA (ß = 0.106), active transport (ß = 0.096), and individual SC (ß = 0.072) after lockdown. Phone use was negatively associated with PA through PC/TV use in the more phone use subgroup. Relationships among screen use, PA, and SC dynamically changed during COVID-19, and phone use that was identified as a bridge and a predictor may be the potential action point for health intervention in youths during lockdown.


Subject(s)
COVID-19 , Social Capital , Humans , Adolescent , COVID-19/epidemiology , COVID-19/prevention & control , Communicable Disease Control , Cross-Sectional Studies , Pandemics/prevention & control , China/epidemiology , Exercise
6.
Phys Chem Chem Phys ; 25(22): 15469-15478, 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37249388

ABSTRACT

Two-dimensional magnetic materials with tunable electronic properties have great potential application in spintronic devices. Here, based on first-principles calculations, we systematically study the electronic structures and magnetic properties of monolayer NiMnBr6. The magnetic ground state of monolayer NiMnBr6 is Néel ferrimagnetic (FIM-Néel) with a critical temperature (Tc) of 45 K. The magnetic properties of monolayer NiMnBr6 can be tuned effectively by strain. The magnetic phase transition from the FIM-Néel state to the ferromagnetic (FM) state can be triggered by applying a compressive strain greater than 4.5%. The Tc of the FIM-Néel state and FM state can be increased to 67 K and 95 K by applying 8.0% tensile and compressive strain, respectively. Monolayer NiMnBr6 in both the FIM-Néel state and FM state has large magnetic anisotropy energy. Remarkably, the monolayer NiMnBr6 in the FIM-Néel state acts as a bipolar ferrimagnetic semiconductor (BFIMS), while the compressive strained monolayer NiMnBr6 in the FM state acts as a half FM semiconductor (HFMS). The magnetic configuration of monolayer NiMnBr6 can also be tuned by carrier doping. Interestingly, for monolayer NiMnBr6 with the HFMS phase, the magnetic phase transition from the FM state to FIM-Néel state can be achieved with the increase of the hole doping concentration, which leads to the achievement of a doping concentration induced carrier spin flip. Our results show that monolayer NiMnBr6 is a promising candidate for exploring two-dimensional magnetism and spintronic devices.

7.
Phys Chem Chem Phys ; 25(8): 6537-6544, 2023 Feb 22.
Article in English | MEDLINE | ID: mdl-36786679

ABSTRACT

Two-dimensional (2D) materials are an excellent platform for surface-enhanced Raman spectroscopy (SERS). However, a poor detection sensitivity hinders their practical application. Exciton resonance (µex) can improve SERS significantly by lending intensity to nearby charge-transfer resonance. Coincidentally, for ReS2, the enhanced µex can be achieved through the injection of excited-state electrons which can adjust the energy band to the SERS detection range. Moreover, ReS2 has strong anisotropic properties, which adds an additional dimension for SERS. Therefore, ReS2 is an ideal candidate to realize highly sensitive anisotropic SERS. In this paper, the metallic T phase of ReS2 is introduced to the semiconducting Td phase by phase engineering. The photoinduced electron tunneling from the T phase to the Td phase can tune exciton emissions to the visible region, which effectively facilitates the photoinduced charge transfer processes. With RhB as the probe molecule, the synergistic resonance effects improve the limit of detection to 10-9 M with the enhancement factor up to about 108. Meanwhile, the obtained ultrasensitive SERS substrates also show good uniformity, stability as well as unique anisotropy. Our results open a new perspective in the improvement of the SERS performance.

8.
Phys Chem Chem Phys ; 25(25): 16962-16967, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37334887

ABSTRACT

Monolayer (ML) NiCl2 exhibits a strong biquadratic exchange interaction between the first neighboring magnetic atoms (B1), as demonstrated by the spin spiral model in J. Ni et al., Phys. Rev. Lett., 2021, 127, 247204. This interaction is crucial for stabilizing the ferromagnetic collinear order within the ML NiCl2. However, they neither point out the role of B1 nor discuss the dispersion relation from spin orbit coupling (SOC) in the spin spiral. As we have done in this work, these parameters might theoretically potentially be derived directly by fitting the calculated spin spiral dispersion relation. Here, we draw attention to the fact that B1 is equivalent to half of J3 in Heisenberg linear interactions and that the positive B1 partially counteracts the negative J3's impact on the spin spiral to make the ML NiCl2 ferromagnetic. The comparatively small J3 + 1/2B1 from the spin spiral led us to believe that J3 could be substituted by B1, yet it still exists and plays a crucial function in magnetic semiconductors or insulators. The dispersion relation, which we also obtain from SOC, displays weak antiferromagnetic behavior in the spin spiral.

9.
Clin Exp Hypertens ; 45(1): 2233717, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37454306

ABSTRACT

BACKGROUND: Anthocyanin plays a protective role in cardiovascular disease through antioxidant effect. Whether anthocyanin can reduce salt-induced hypertension and the related mechanisms remain unclear. METHODS: Chronic infusion of vehicle (artificial cerebrospinal fluid, aCSF, 0.4 µL/h) or anthocyanin (10 mg/kg, 0.4 µL/h) into bilateral paraventricular nucleus (PVN) of Sprague-Dawley rats was performed. Then, the rats were fed a high salt diet (8% NaCl, HS) or normal salt diet (0.9%, NaCl, NS) for 4 weeks. RESULTS: High salt diet induced an increase in blood pressure and peripheral sympathetic nerve activity (increased LF/HF and decreased SDNN and RMSSD), which was accompanied by increased reactive oxygen species (ROS) production and angiotensin II type-1 receptor (AT1R) expression and function in the PVN. Moreover, the NOD-like receptor protein 3 (NLRP3) and related inflammatory proteins (caspase-1) expression, the pro-inflammatory cytokine levels including IL-1ß and TNF-α were higher in PVN of rats with a high salt diet. Bilateral PVN infusion of anthocyanin attenuated NLRP3-dependent inflammation (NLRP3, caspase-1, IL-1ß and TNF-α) and ROS production, reduced AT1R expression and function in PVN and lowered peripheral sympathetic nerve activity and blood pressure in rats with salt-induced hypertension. CONCLUSIONS: Excessive salt intake activates NLRP3-dependent inflammation and oxidative stress and increased AT1R expression and function in the PVN. Bilateral PVN infusion of anthocyanin lowers peripheral sympathetic nerve activity and blood pressure in rats with salt-induced hypertension by improvement of expression and function of AT1R in the PVN through inhibiting NLRP3 related inflammatory and oxidative stress.


Subject(s)
Anthocyanins , Hypertension , Rats , Animals , Anthocyanins/adverse effects , Anthocyanins/metabolism , Sodium Chloride, Dietary/adverse effects , Reactive Oxygen Species/metabolism , Sodium Chloride/adverse effects , Sodium Chloride/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Tumor Necrosis Factor-alpha/metabolism , Rats, Sprague-Dawley , Hypertension/chemically induced , Hypertension/metabolism , Sympathetic Nervous System , Inflammation/metabolism , Caspases/metabolism , Paraventricular Hypothalamic Nucleus/metabolism
10.
Afr J Reprod Health ; 27(5): 95-104, 2023 May.
Article in English | MEDLINE | ID: mdl-37584934

ABSTRACT

Extremely low-frequency electromagnetic radiation (ELF-EMF) are generated by electrical devices and power systems (1 to 300 Hz). Although several studies have demonstrated that ELF-EMF may beassociated with an increased risk of adverse pregnancy outcomes, other studies have shown no evidence of associations. This meta-analysis was conducted to assess the effect of extremely low frequency electromagnetic radiation on pregnancy outcomes. The following electronic bibliographic databases were searched to identify relevant studies: PubMed, Web Of Science, Cochrane library, Embase, EBSCO. In addition, the manual retrieval of relevant references was conducted as a supplement. Select all eligible studies published from Database construction library to March 10, 2021. Search type for queue research on influence of electromagnetic field radiation on pregnancy results. Data were screened and extracted independently by two researchers. Review Manager 5.3 software was used for the meta-analysis. There was no significant increase in the risk of miscarriage, stillbirth, birth defects and preterm delivery in the pregnant women who lived near the electromagnetic fields compared with the control group. Conclusions: No correlation has been found between maternal ELF-EMF exposure and miscarriage, stillbirth, neonatal birth defects and preterm delivery, while the effects on small gestational age and low birth weight are still uncertain. Related research with high-quality large samples and different regions are still needed for further verification.


Subject(s)
Abortion, Spontaneous , Premature Birth , Infant, Newborn , Pregnancy , Humans , Female , Stillbirth/epidemiology , Pregnancy Outcome/epidemiology , Electromagnetic Radiation
11.
Arch Biochem Biophys ; 715: 109082, 2022 01 15.
Article in English | MEDLINE | ID: mdl-34767797

ABSTRACT

Pulmonary fibrosis is a severe condition with limited therapeutic options and characterized by increased fibroblast activation and progressive accumulation of extracellular matrix. Ghrelin, a gastrointestinal hormone, has been reported to possess protective roles in lung diseases including pulmonary fibrosis. However, the precise mechanisms underlying the protective effects of ghrelin remain unknown. The present study was designed to investigate the effects of ghrelin on transforming growth factor-ß1 (TGF-ß1)-induced pulmonary fibrosis in vitro and in vivo and the possible mechanism of action. It was found that ghrelin significantly attenuated TGF-ß1-induced fibrotic responses in human lung fibroblast (IMR-90) cells and bleomycin (BLM)-induced fibrotic lung tissues. Meanwhile, ghrelin decreased the expressions of miR-125a-5p and phosphorylated smad2/3 and increased protein expressions of Kruppel-like factor 13 (KLF13) in vivo and in vitro. Ghrelin-induced anti-fibrotic effects and smad2/3 downregulation in TGF-ß1-stimulated IMR-90 cells were markedly reversed by miR-125a-5p mimics and KLF13 siRNA. Furthermore, miR-125a-5p directly targeted KLF13 in IMR-90 cells. Our findings suggest that ghrelin attenuates TGF-ß1-induced pulmonary fibrosis via the miR-125a-5p/KLF13 axis, which supports ghrelin as a new therapeutic agent against pulmonary fibrosis by antagonizing the TGF-ß1 signaling pathway.


Subject(s)
Cell Cycle Proteins/metabolism , Ghrelin/metabolism , Kruppel-Like Transcription Factors/metabolism , MicroRNAs/metabolism , Pulmonary Fibrosis/metabolism , Repressor Proteins/metabolism , Animals , Bleomycin , Cell Line , Down-Regulation , Humans , Male , Pulmonary Fibrosis/chemically induced , Rats, Sprague-Dawley , Signal Transduction/physiology , Smad2 Protein/metabolism , Smad3 Protein/metabolism , Transforming Growth Factor beta1
12.
Appl Microbiol Biotechnol ; 106(5-6): 2121-2131, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35190846

ABSTRACT

A phage PEf771 that specifically infects and lyses pathogenic Enterococcus faecalis YN771 in patients with refractory periapical periodontitis was used to investigate resistance against E. faecalis infection in vitro and in vivo. PEf771 completely lysed YN771 within 3 h, with a multiplicity of infection of 1. Compared with ten routinely used clinical antibiotics, PEf771 demonstrated the highest bacteriostatic effect within 72 h. The antibacterial effect of PEf771 on extracted teeth within 72 h was better than that of conventional root canal disinfectants such as camphorated phenol, formaldehyde cresol solution, and Ca(OH)2 (P < 0.05) within 72 h. Using E. faecalis, intraperitoneal and periapical infection models were established using Sprague Dawley (SD) rats. The results showed that all SD rats inoculated with 9.6 × 1011 CFU/mL E. faecalis YN771 or 2.9 × 1011 CFU/mL E. faecalis RYN771 died within 8 h. Additionally, all SD rats inoculated with YN771 and treated with antibiotics died within 72 h. Although SD rats inoculated with RYN771 and treated with antibiotics survived for 72 h, the pathological anatomy of these rats showed purulent discharge, numerous pus and blood-filled ascites, and extensive liver abscesses. Notably, YN771 rats treated with PEf771 and RYN771 rats treated with RPEf771 survived for 72 h, and their pathological anatomy showed that the liver, kidneys, intestine, and mesenteries were normal. Computed tomography analysis of SD rats infected with periapical periodontitis showed pathological changes in experimental teeth inoculated with YN771, despite undergoing a normal root canal treatment. Contrastingly, none of the experimental teeth exhibited root periapical inflammation following PEf771 treatment. Hematoxylin and eosin staining revealed a gap between the periodontal ligament and the cementum of experimental teeth, whereas PEf771-treated teeth exhibited normal results. These findings suggested that phage therapy using PEf771 might effectively prevent E. faecalis infection after root canal treatment.Key points• Compared with common clinical antibiotics, PEf771 showed the highest antibacterial.• The liver, kidney, intestine, and mesentery of SD rats treated with PEf771 were normal.• Phage therapy can effectively prevent E. faecalis YN771 and RYN771 infection.


Subject(s)
Periapical Periodontitis , Phage Therapy , Animals , Enterococcus faecalis , Humans , Periapical Periodontitis/microbiology , Periapical Periodontitis/therapy , Rats , Rats, Sprague-Dawley , Root Canal Therapy/methods
13.
Small ; 17(19): e2100102, 2021 May.
Article in English | MEDLINE | ID: mdl-33788423

ABSTRACT

Organic resistive memory (ORM) offers great promise for next-generation high-density multilevel-cell (MLC) data storage. However, the fine tuning of crystalline order among its active layer still remains challenging, which largely restricts ORM behavior. Here, an exceptional solid-state transition from disordered orientations to highly-uniform orientation within the ORM layer is facilely triggered via molecular strategic tailoring. Two diketopyrrolopyrrole-based small molecular analogues (NI1 TDPP and NI2 TDPP) are demonstrated to display different symmetry. The asymmetric NI1 TDPP shows an irregular solid-state texture, while the centro-symmetric NI2 TDPP conforms to an ordered out-of-plane single-crystalline pattern that aligns with the foremost charge transportation along the substrate normal, and exhibits excellent MLC memory characteristics. Moreover, this highly oriented pattern guarantees the large-area film uniformity, leading to the twofold increase in the yield of as-fabricated ORM devices. This study reveals that the solid-state crystalline nanostructural order of organic materials can be controlled by reasonable molecular design to actuate high-performance organic electronic circuits.

14.
Opt Express ; 28(23): 34035-34044, 2020 Nov 09.
Article in English | MEDLINE | ID: mdl-33182881

ABSTRACT

Mirror-asymmetric split-ring metamaterials with high quality factor in the terahertz (THz) band, consisting of patterned high magnetic permeability and low coercivity FeNHf films deposited on high resistivity silicon substrates, were studied for their magnetic field tunable response in frequency and transmission. Dynamic tuning of terahertz transmission and electromagnetic resonance modes were investigated theoretically and experimentally as a function of magnetization of the FeNHf film. Experimental results indicate that the metamaterial structure provides a giant tunability of resonance frequency (Δfr/fr=3.3%) and transmittivity (21%) at a frequency of 0.665 THz under a low magnetic field of H=100 Oe. Remarkable tuning coefficients of frequency and transmittivity, 0.23 GHz/Oe and 0.21%/Oe, respectively, were measured. Finite difference time domain simulations reveal that the incredible tunability stems predominately from the response of the THz dynamic magnetic field to magnetization. As a result, the metamaterial, consisting of a simple magnetic split-ring microstructure, provides previously unimagined paths to tunable devices for potential use in emerging THz technologies including 6G communication systems and networks.

15.
Phys Chem Chem Phys ; 22(37): 21403-21411, 2020 Sep 30.
Article in English | MEDLINE | ID: mdl-32940304

ABSTRACT

The temperature-dependent spin-reorientation transition (SRT) and spin interaction mechanism of bulk TmFeO3 were studied by the electron paramagnetic resonance (EPR) method. The combined experimental results of magnetic curves and EPR spectra confirmed that there is an antiferromagnetic transition at 85 K with a reentering ferromagnetic state due to the spin-reorientation behavior. In the high-temperature region of T > 90 K, there are three distinct resonance peaks in the EPR spectrum, which indicates the presence of multiple magnetic phases (canted antiferromagnetic, weak ferromagnetic, and paramagnetic phases). In the low-temperature region (T < 85 K), the temperature dependence of the EPR linewidth, effective g-factor, and intensity can be used to infer a strong spin-lattice correlation. Different magnetic interactions such as Fe3+-Fe3+, Fe3+-Tm3+, and Tm3+-Tm3+ lead to a paramagnetic-canted antiferromagnetic phase at T > 85 K, with SRT between 85-65 K and ferromagnetic interaction at the lower temperature, respectively. Above 90 K, we find that the spin relaxation mechanism is determined by the mixture of spin-spin and spin-lattice interactions. Below 85 K, the transverse relaxation rate increases with the decrease in temperature, which is consistent with the weakening of the fluctuating internal field in this temperature region. This EPR detection provides a new method to clarify the strong spin coupling in antiferromagnetic materials.

16.
Angew Chem Int Ed Engl ; 59(51): 23252-23260, 2020 Dec 14.
Article in English | MEDLINE | ID: mdl-32881302

ABSTRACT

Recently, various titanium dioxide (TiO2 ) nanostructures have received increasing attention in the fields of energy conversion and storage owing to their electrochemical properties. However, these particulate nanomaterials exclusively exist in the powder form, which may cause health risks and environmental hazards. Herein we report a novel, highly elastic bulk form of TiO2 for safe use and easy recycling. Specifically, TiO2 nanofibrous aerogels (NAs) consisting of resiliently bonded, flexible TiO2 nanofibers are constructed, which have an ultralow bulk density, ultrahigh porosity, and excellent elasticity. To promote charge transfer, they are subjected to lithium reduction to generate abundant oxygen vacancies, which can modulate the electronic structure of TiO2 , resulting in a conductivity up to 38.2 mS cm-1 . As a proof-of-concept demonstration, the conductive and elastic TiO2 NAs serve as a new type of self-supported electrocatalyst for ambient nitrogen fixation, achieving an ammonia yield of 4.19×10-10  mol s-1 cm-2 and a Faradaic efficiency of 20.3 %. The origin of the electrocatalytic activity is revealed by DFT calculations.

17.
J Cell Physiol ; 234(3): 2552-2565, 2019 03.
Article in English | MEDLINE | ID: mdl-30144053

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease with increasing occurrence, high death rates and unfavorable treatment regimens. In the current study, we identified the expression of microRNA-9 (miR-9) and anoctamin-1 (ANO1) in IPF mouse models induced by bleomycin, and their effects on inflammation and fibroblast proliferation through the transforming growth factor-ß (TGF-ß)-Smad3 pathway. To verify the targeting relationship between miR-9 and ANO1, we used bioinformatics prediction and conducted a dual-luciferase reporter gene assay. The underlying regulatory mechanisms of miR-9 and the target gene ANO1 were investigated mainly with the treatment of miR-9 mimic, miR-9 inhibitor, or siRNA against ANO1 in fibroblasts isolated from IPF mice. Enzyme-linked immunosorbent assay was performed to investigate the effect of miR-9 or ANO1 on inflammatory factors. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry were used to detect fibroblast proliferation and apoptosis. Reverse transcription quantitative polymerase chain reaction and western blot analysis were applied to measure the expression of the TGF-ß-Smad3 pathway-related genes. The determination of luciferase activity suggested that miR-9 targets ANO1. Upregulation of miR-9 or silencing of ANO1 intensified inflammation in IPF, promoted proliferation and inhibited apoptotic ability of lung fibroblasts. MiR-9 negatively modulated ANO1, and thus activated the TGF-ß-Smad3 pathway. These findings suggest that miR-9 can indirectly activate the TGF-ß-Smad3 pathway by inhibiting the expression of ANO1, thereby aggravating inflammation, promotes proliferation and suppressing apoptosis of lung fibroblasts in mice models of IPF.


Subject(s)
Anoctamin-1/metabolism , Down-Regulation/genetics , Fibroblasts/metabolism , Idiopathic Pulmonary Fibrosis/metabolism , MicroRNAs/genetics , Animals , Apoptosis/drug effects , Bleomycin/pharmacology , Cell Proliferation/drug effects , Down-Regulation/drug effects , Idiopathic Pulmonary Fibrosis/genetics , Lung/metabolism , Mice , Signal Transduction/drug effects , Smad3 Protein/metabolism , Transforming Growth Factor beta/metabolism
18.
Opt Express ; 27(26): 37274-37285, 2019 Dec 23.
Article in English | MEDLINE | ID: mdl-31878510

ABSTRACT

We propose an evaluation method to judge the fitting extent to ophthalmic lens for the individual wearer. An Eye-Lens-Object optical system is set according to wearer's visual performance and the characteristic of ophthalmic lens assembly. A visual reference surface is proposed to calculate the object distance. The RMS radius of the spot diagram and MTF average value from optical design software Zemax are regarded as the criterion of assessing the image quality on the retina. Three cases are simulated to verify that our method is effective. The wearers can experience a comfortable wearing feeling when the evaluation method is used during the design of ophthalmic lens. The validity of our method is demonstrated to instruct designing the progressive addition lens with the freeform surface.

19.
Opt Express ; 24(26): A1612-A1617, 2016 Dec 26.
Article in English | MEDLINE | ID: mdl-28059318

ABSTRACT

SrTcO3 as a new star of solar energy material is investigated in terms of its band gap evolution with biaxial strain from first-principles calculations. Compared to the theoretical equilibrium lattice constant a(b) of bulk SrTcO3, a set of lattice constants with a deviation of -8.75% to +3.35% are considered to include the strain effect. Since the in-plane lattice constant of SrTcO3 is larger than that of the commonly used substrate SrTiO3(STO)/La0.3Sr0.7Al0.35Ta0.35O9 (LSAT)/NdGaO3(NGO)/LaAlO3(LAO), we mainly focus on the modulation of compressive strain. It is found that the band gap decreases with increasing compressive/tensile strain. When the compressive strain reaches 8.75%, the band gap drops to zero and an insulator-metal phase transition appears. Particularly, upon a compressive strain of 1.3%/2.2%/2.4%/4.1%, which can be realized by growing SrTcO3 on substrate STO/LSAT/NGO/LAO, the band gap becomes 1.56/1.47/1.43/1.12 eV, which falls in the range for efficient solar cell materials. Our work suggests that SrTcO3 is a good candidate for a new solar energy material.

20.
Opt Express ; 22(24): 29435-44, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25606878

ABSTRACT

The existence and stability of gap solitons are investigated in the semi-infinite gap of a parity-time (PT)-symmetric periodic potential (optical lattice) with a higher-order diffraction. The Bloch bands and band gaps of this PT-symmetric optical lattice depend crucially on the coupling constant of the fourth-order diffraction, whereas the phase transition point of this PT optical lattice remains unchangeable. The fourth-order diffraction plays a significant role in destabilizing the propagation of dipole solitons. Specifically, when the fourth-order diffraction coupling constant increases, the stable region of the dipole solitons shrinks as new regions of instability appear. However, fundamental solitons are found to be always linearly stable with arbitrary positive value of the coupling constant. We also investigate nonlinear evolution of the PT solitons under perturbation.


Subject(s)
Light , Optical Phenomena , Nonlinear Dynamics , Time Factors
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