Direct mapping of bending and torsional dynamics in individual nanostructures.

Investigating coherent acoustic vibrations in nanostructured materials provides fundamental insights into optomechanical responses and microscopic energy flow. Extensive measurements of vibrational dynamics have been performed for a wide variety of nanoparticles and nanoparticle assemblies. However, virtually all of them show that only the dilation modes are launched after laser excitations, and the acoustic bending and torsional motions, which are commonly observed in photoexcited chemical bonds, are absent. Unambiguous identification and refined characterization of these "missing" modes have been a long-standing issue. In this report, we investigated the acoustic vibrational dynamics of individual Au nanoprisms on free-standing graphene substrates using an ultrafast high-sensitivity dark-field imaging approach in four-dimensional transmission electron microscopy. Following optical excitations, we observed low-frequency multiple-mode oscillations and higher superposition amplitudes at nanoprism corners and edges on the subnanoparticle level. In combination with finite-element simulations, we determined that these vibrational modes correspond to out-of-plane bending and torsional motions, superimposed by an overall tilting effect of the nanoprisms. The launch and relaxation processes of these modes are highly pertinent to substrate effects and nanoparticle geometries. These findings contribute to the fundamental understanding about acoustic dynamics of individual nanostructures and their interaction with substrates.

Development and Validation of Prediction Models for Exacerbation, Frequent Exacerbations and Severe Exacerbations of Chronic Obstructive Pulmonary Disease: A Registry Study in North China.

In COPD patients, exacerbation has a detrimental influence on the quality of life, disease progression and socioeconomic burden. This study aimed to develop and validate models to predict exacerbation, frequent exacerbations and severe exacerbations in COPD patients. We conducted an observational prospective multicenter study. Clinical data of all outpatients with stable COPD were collected from Beijing Chaoyang Hospital and Beijing Renhe Hospital between January 2018 and December 2019. Patients were followed up for 1 year. The data from Chaoyang Hospital was used for modeling dataset, and that of Renhe Hospital was used for external validation dataset. The final dataset included 456 patients, with 326 patients as the model group and 130 patients as the validation group. Using LABA + ICS, frequent exacerbations in the past year and CAT score were independent risk factors for exacerbation in the next year (OR = 2.307, 2.722 and 1.147), and FVC %pred as a protective factor (OR = 0.975). Combined with chronic heart failure, frequent exacerbations in the past year, blood EOS counts and CAT score were independent risk factors for frequent exacerbations in the next year (OR = 4.818, 2.602, 1.015 and 1.342). Using LABA + ICS, combined with chronic heart failure, frequent exacerbations in the past year and CAT score were independent risk factors for severe exacerbations in the next year (OR = 1.950, 3.135, 2.980 and 1.133). Based on these prognostic models, nomograms were generated. The prediction models were simple and useful tools for predicting the risk of exacerbation, frequent exacerbations and severe exacerbations of COPD patients in North China.

Rutile Nanorod/Anatase Nanowire Junction Array as Both Sensor and Power Supplier for High-Performance, Self-Powered, Wireless UV Photodetector.

Self-powered UV photodetectors based on TiO2 nanotree arrays have captured much attention in recent years because of their many advantages. In this work, rutile/anatase TiO2 (R/A-TiO2 ) heterostructured nanotree arrays are fabricated by assembling anatase nanowires as branches on rutile nanorods. External quantum efficiencies as high as 90% are reached at 325 nm. These high quantum efficiencies are related to the higher amount of light harvesting due to the larger surface area, the better separation ability of the photogenerated carriers by the rutile/anatase heterostructure, and the faster electron transport, related to the 1D nanostructure and lattice connection at the interface of the two kinds of TiO2 . Furthermore, a self-powered wireless UV photodetector is shown with excellent wireless detection performance. Such devices will enable significant advances for next-generation photodetection and photosensing applications.

Improved Lithium Storage Performance of a TiO2 Anode Material Doped by Co.

TiO2 is a promising anode material for lithium-ion batteries (LIBs) due to its low cost, suitable operating voltage, and excellent structural stability. The inherent poor electron conductivity and low ion diffusion coefficient, however, severely limit its application in lithium storage. Here, Co-doped TiO2 is synthesized by a hydrothermal method as an anode material since Co@TiO2 possesses a large specific surface area and high electronic conductivity. Thanks to the Co dopants, the ion diffusion and electron transport are both greatly improved, which is very beneficial for cycle stability, coulombic efficiency (CE), reversible capacity, and rate performance. As a result, Co@TiO2 shows a high reversible capacity of 227 mAh g-1 at 3 C, excellent rate performance, and cycling stability with a capacity of about 125 mAh g-1 at 10C after 600 cycles (1 C = 170 mA g-1).

Gender differences in clinical characteristics of patients with non-cystic fibrosis bronchiectasis in different age groups in northern China.

INTRODUCTION: Patient gender has clinical and prognostic implications in non-cystic fibrosis bronchiectasis, yet the potential effect of gender on clinical characteristics of patients with non-cystic fibrosis bronchiectasis is still unclear. OBJECTIVES: This study aimed to investigate the gender differences in clinical characteristics of patients with bronchiectasis in different age groups in northern China. METHODS: A total of 777 patients diagnosed with bronchiectasis were retrospectively included in Beijing Chaoyang Hospital and divided into two groups by gender: the male group and the female group. Each group was then subdivided into two according to their age (≤65 and >65 years). Gender differences in clinical characteristics were compared in all patients with bronchiectasis in the two age groups, respectively. RESULTS: A total of 777 bronchiectasis patients were included. Of these patients, the prevalence of female non-smokers was substantially higher than that of male non-smokers (94.0% vs. 36.8%). There were gender differences in etiology of bronchiectasis, with more post-measles and connective tissue disease in females (p = 0.006 and 0.002 separately) and more chronic obstructive pulmonary disease (COPD) in males (p < 0.001). The male group had a significantly higher C-reactive protein (CRP) on admission (p = 0.03). Female patients showed a higher forced expiratory volume in 1 s as percentage of predicted volume (FEV1%pred) and forced vital capacity rate of 1 s (FEV1/FVC) (p < 0.001), lower partial pressure of carbon dioxide (PaCO2 ) (p = 0.04) and hospital costs (p = 0.02) than males, and a higher prevalence of infection with Pseudomonas aeruginosa in >65-year-old group (p = 0.019). CONCLUSIONS: There were many differences between male and female patients in smoking status, etiology, lung function, blood gas analysis, and hospital costs in all patients or different age groups.

Efficacy and safety of glibenclamide therapy after intracerebral haemorrhage (GATE-ICH): A multicentre, prospective, randomised, controlled, open-label, blinded-endpoint, phase 2 clinical trial.

Background: Glibenclamide is a promising agent for treating brain oedema, but whether it improves clinical outcomes in patients with intracerebral haemorrhage (ICH) remains unclear. In this study, we aimed to explore the efficacy and safety of glibenclamide treatment in patients with acute ICH. Methods: The Glibenclamide Advantage in Treating Oedema after Intracerebral Haemorrhage (GATE-ICH) study was a randomised controlled phase 2 clinical trial conducted in 26 hospitals in the northwest of China, recruiting patients with acute ganglia ICH no more than 72 h after onset from Dec 12, 2018 to Sept 23, 2020. During the first 7 days after enrolment, patients randomly assigned to the glibenclamide group were given glibenclamide orally (1.25 mg, 3/day) and standard care, while patients randomly assigned to the control group were given standard care alone. The computer-generated randomisation sequence was prepared by a statistician not involved in the rest of the study. Randomisation was computer-generated with a block size of four. The allocation results were unblinded to participants and investigators. The primary outcome was the percentage of patients with poor outcome (defined as modified Rankin Scale [mRS] score of ≥3) at day 90. The trial was registered at ClinicalTrials.gov (NCT03741530). Findings: 220 participants were randomised and 200 participants (mean [standard deviation] age, 56 [11] years; sex, 128 [64.0%] male and 72 [36.0%] female) were included in the final analysis, with 101 participants randomly assigned to the control group and 99 to the glibenclamide group. The incidence of poor outcome at day 90 was 20/99 (20.2%) in glibenclamide group and 30/101 (29.7%) in control group (absolute difference, 9.5%; 95% confidence interval [CI], -3.2%-21.8%; P = 0.121) with adjusted odds ratios of 0.54 (95% CI, 0.24-1.20; P = 0.129). No significant difference was found in the overall rates of adverse events or serious adverse events between groups. However, the incidence of asymptomatic hypoglycaemia was significantly higher in glibenclamide group than control group (15/99 [15.2%] vs 0/101 [0.0%]; absolute difference, 15.2%; 95% CI, 7.5%-24.1%; P < 0.001). Interpretation: Our study provides no evidence that glibenclamide (1.25 mg, 3/day) significantly reduces the proportion of poor outcome at day 90 after ICH. In addition, glibenclamide could result in higher incidence of hypoglycaemia. Larger trials of glibenclamide with optimised medication regimen are warranted. Funding: Shaanxi Province Key Research and Development Project (2017DCXL-SF-02-02) and Shaanxi Province Special Support Program for Leading Talents in Scientific and Technological Innovation (tzjhjw).

Revealing Electron-Phonon Interactions and Lattice Dynamics in Nanocrystal Films by Combining in Situ Thermal Heating and Femtosecond Laser Excitations in 4D Transmission Electron Microscopy.

We present a comparative investigation on static equilibrium and transient structural dynamics of nanocrystalline gold films on silicon nitride supports performed at various in situ temperatures and by ultrafast laser excitations in a four-dimensional ultrafast transmission electron microscope (4D-UTEM). The change of relative diffraction intensity and lattice spacing with rising temperatures was systematically measured for {220} Debye-Scherrer rings via the in situ heating technique, which leads to a precise determination of the actual Debye temperature and a finding of significant depression of lattice expansions in the films. The diffraction intensity/lattice spacing-temperature relationship calibrated by the static, thermally equilibrium observations was then employed for investigating ultrafast transient dynamics on the same specimen region. The electron-phonon coupling constant g was determined to be 7.2 × 1015 W/m3 K in combination with simple two-temperature model analysis. We found a marked variation of temperature rise maximum (at quasi-equilibrium states) in between the temporal evolutions of lattice spacing and diffraction intensity, a phenomenon which may only be explained by the effect of nonthermal equilibrium relaxation dynamics following femtosecond laser excitations. The method demonstrated here can thus be applied to quantitative evaluations of nonthermal equilibrium contributions during the electron-lattice thermalization.

Effects of Graphene Quantum Dots on the Self-Renewal and Differentiation of Mesenchymal Stem Cells.

The influence of graphene quantum dots (GQDs) on key characteristics of bone marrow derived mesenchymal stem cells (MSCs) phenotype (i.e., self-renewal, differentiation potential, and pluripotency) is systematically investigated in this work. First, the viability and impact of GQDs on the self-renewal potential of MSCs is evaluated in order to determine a threshold for the exposing dose. Second, GQDs uptake by MSCs is confirmed due to the excellent fluorescent properties of the particles. They exhibit a homogenous cytoplasmatic distribution that increases with the time and concentration. Third, the impact of GQDs on the osteogenic differentiation of MSCs is deeply characterized. An enhanced activity of alkaline phosphatase promoted by GQDs indicates early activation of osteogenesis. This is also confirmed upon GQD-induced up-regulation of phenotypically related osteogenic genes (Runx2, osteopontin, and osteocalcin) and specific biomarkers expression (osteopontin and osteocalcin). GQDs also effectively enhance the formation of calcium-rich deposits characteristics of osteoblasts. Furthermore, genes microarray results indicate that the enhanced osteogenic differentiation of MSCs by GQDs is in progress through a bone morphogenetic protein and transforming growth factor-ß relative signaling pathways. Finally, intracytoplasmatic lipid detection shows that GQDs can also promote the adipogenic differentiation of MSCs, thus confirming the prevalence of their pluripotency potential.

Localized committed differentiation of neural stem cells based on the topographical regulation effects of TiO2 nanostructured ceramics.

In this study, a porous-flat TiO2 micropattern was fabricated with flat and nanoporous TiO2 ceramics for investigating the effect of topography on neural stem cell (NSC) differentiation. This finding demonstrates that localized committed differentiation could be achieved in one system by integrating materials with different topographies.

Surface charge regulation of osteogenic differentiation of mesenchymal stem cell on polarized ferroelectric crystal substrate.

Polarized ferroelectric crystal lithium niobate wafers with different cuts are selected to offer differently charged surfaces. By induction of the mesenchymal stem cells differentiation into osteoblasts on different charged surfaces, the specific osteogenic-associated markers are assessed and the results illustrate that the positively charged wafer surface enhances rBMMSCs osteogenic differentiation.

Association between MTHFR gene polymorphisms, smoking, and the incidence of vascular dementia.

This study investigated the relationship between N5,N10-methylene tetrahydrofolic acid reductase (MTHFR) polymorphisms, smoking, and vascular dementia (VD). Polymerase chain reaction-restriction fragment length polymorphism analysis was used to analyze the frequency of the C/T polymorphism at position 677 of the MTHFR gene in 304 VD patients and 300 control patients with nondementia cerebral infarction. The CC, CT, and TT genotype frequencies of the MTHFR gene were 43.42%, 32.57%, and 24.01%, respectively, in the VD group, and 50.67%, 32.00%, and 17.33%, respectively, in the control group. The T allele frequency was significantly higher in the VD group than in the control group (P < .05). Among patients who smoked, the relative risk of VD in patients with the TT genotype and T allele was higher than in the control group (P < .05). Therefore, the smoking group with the T allele has the highest risk of VD, and synergy appears to exist between the MTHFR gene polymorphisms and smoking in susceptibility to VD.

Efficacy and safety of mildronate for acute ischemic stroke: a randomized, double-blind, active-controlled phase II multicenter trial.

BACKGROUND AND OBJECTIVE: Mildronate, an inhibitor of carnitine-dependent metabolism, is considered to be an anti-ischemic drug. This study is designed to evaluate the efficacy and safety of mildronate injection in treating acute ischemic stroke. METHODS: We performed a randomized, double-blind, multicenter clinical study of mildronate injection for treating acute cerebral infarction. 113 patients in the experimental group received mildronate injection, and 114 patients in the active-control group received cinepazide injection. In addition, both groups were given aspirin as a basic treatment. Modified Rankin Scale (mRS) score was performed at 2 weeks and 3 months after treatment. National Institutes of Health Stroke Scale (NIHSS) score and Barthel Index (BI) score were performed at 2 weeks after treatment, and then vital signs and adverse events were evaluated. RESULTS: A total of 227 patients were randomized to treatment (n = 113, mildronate; n = 114, active-control). After 3 months, there was no significant difference for the primary endpoint between groups categorized in terms of mRS scores of 0-1 and 0-2 (p = 0.52 and p = 0.07, respectively). There were also no significant differences for the secondary endpoint between groups categorized in terms of NIHSS scores of >5 and >8 (p = 0.98 and p = 0.97, respectively) or BI scores of >75 and >95 (p = 0.49 and p = 0.47, respectively) at 15 days. The incidence of serious adverse events was similar between the two groups. CONCLUSION: Mildronate injection is as effective and safe as cinepazide injection in treating acute cerebral infarction.

Clinical presentation and imaging of general paresis due to neurosyphilis in patients negative for human immunodeficiency virus.

The clinical presentations and MRI of six patients with general paresis due to neurosyphilis were reviewed. Diagnosis was based on neurological and psychiatric symptoms, positive Treponema pallidum hemagglutination in cerebrospinal fluid (CSF) and sera, and serology that was negative for human immunodeficiency virus by enzyme-linked immunosorbent assay. Most patients had lymphocytic, monocytic pleocytosis and high protein levels in their CSF. One patient had periodic lateral epileptiform discharges, one patient had epileptiform discharges and three patients had slowing of background activity on electroencephalography. Two patients had hyperintense signal abnormalities in the anterior and mesial temporal lobe, while four patients were found by MRI to have cerebral atrophy. Three patients developed white matter lesions. Therefore, clinical, electroencephalography and MRI findings are valuable in the diagnosis of general paresis of neurosyphilis.