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High repetition frequency (HRF) ultrashort pulse fiber laser has been widely used in laser cold processing. The technical solutions such as short cavity length fiber laser have been proposed to achieve HRF ultrashort pulse output recently. However, the application of material-based saturable absorbers in this field has been astricted due to the low modulation depth, low damage resistance threshold, and high saturation fluence. Here, we designed a one-dimensional asymmetric photonic crystal with defect layer (1D-APCDL) as a novel saturable absorber, where the defect layer is Bi1.6Sb0.4Te3 with high modulation depth. The harmonic pulse with 3.82 GHz repetition frequency is achieved at the wavelength of 1562 nm, which is the highest repetition frequency of the topological insulator-based ring fiber laser so far to the best of our knowledge. The research provides a new saturable absorber solution, and provides a new idea for the application of material-based nonlinear optical chip in high-repetition frequency ultrashort pulse fiber lasers.

Aims: This systematic review and meta‐analysis aimed to evaluate the effects of home‐based telehealth compared with usual care on six‐minute walking distance (6MWD), health‐related quality of life, anxiety and depression in patients with chronic obstructive pulmonary disease. Methods: We identified randomized controlled trials through a systematic multidatabase search. Titles and abstracts were assessed for relevance. Two authors independently extracted data and assessed the risk of bias and quality of evidence. Meta‐analyses were conducted using Review Manager and Stata. Results: We included 32 randomized controlled trials (n = 5232). Devices used for home‐based telehealth interventions included telephones, videos, and combined devices. The quality of the evidence was downgraded due to high risk of bias, imprecision, and inconsistency. Home‐based telehealth significantly increased 6MWD by 35 m (SD = 30.42) and reduced symptom burden by 3 points (SD = −2.30) on the COPD assessment test compared with usual care. However, no significant differences in anxiety and depression were noted between the home‐based telehealth group and the standard care group. In subgroup analysis, home‐based telehealth significantly improved 6MWD and health status after 6–12 months and >12 months. Conclusion: Low quality evidence showed that home‐based telehealth interventions reduce symptom burden and increase walking distance to a clinically meaningful extent in patients with COPD. However, no effects on depression and anxiety were observed. Summary statement: What is already known about the topic? In the context of chronic obstructive pulmonary disease progression, exacerbation of symptoms results in negative impacts on physical condition and psychological status.The overall effect of telehealth for patients living with chronic obstructive pulmonary disease is unclear based on different results reported in existing studies. What this paper adds? Home‐based telehealth improved the six‐minute walking distance and health status in patients with chronic obstructive pulmonary disease, but it did not improve anxiety and depression.Home‐based telehealth based on combined devices but not telephone or video improved the six‐minute walking distance and health status.Home‐based telehealth significantly improved six‐minute walking distance and health status in the 6–12 months subgroup and the more than 12 months subgroup but not at <6 months. The implications of this paper: Telehealth offers a feasible method to provide long‐term and regular health care to patients with chronic obstructive pulmonary disease living at home.Telehealth can help expand the recognition, accessibility and application of medical care services for patients with chronic obstructive pulmonary disease. [ABSTRACT FROM AUTHOR]

The catalytic cyclocondensation of in situ activated α,β-unsaturated carboxylic acids was developed. N-heterocyclic carbenes efficiently catalyzed the generation of a,bunsaturated acyl azolium intermediates from a,b-unsaturated carboxylic acids via in situ generated mixed anhydrides for the enantioselective [3+2] and [3+3] cyclocondensation with aamino ketones and alkyl(aryl)imines, respectively. The corresponding pyrrolidinones and dihydropyridinones were isolated in good yields with high to excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Abstract: Propofol has been shown to exert neuroprotective effects. Delayed rectifier potassium current (I K) was reported to be closely related to neuronal damage. This study was designed to test the effects of propofol on I K in rat parietal cortical neurons and the involvement of PKC in this activity. Whole-cell patch-clamp recordings were performed in rat parietal cortical neurons. The amplitudes of I K were recorded before and after the addition of different concentrations of propofol. Propofol concentration-dependently inhibited I K with an IC50 value of 36.3±2.7μM. Moreover, propofol caused a downward shift of the I–V curve of I K in a concentration dependent manner. The kinetics of I K was altered by propofol, with decreased activation and delayed recovery of I K. Pretreatment with calphostin-C (a non-selective inhibitor of PKC) or PKC epsilon translocation inhibitor peptide (PKC epsilon inhibitor) abrogated the inhibition of I K by propofol. In conclusion, propofol inhibited I K via the activation of PKC epsilon in rat cerebral parietal cortical neurons. [ABSTRACT FROM AUTHOR]

The conventional dynamic tests of composite foundation were reviewed and the velocity or mechanical admittance method for a block on single-piled composite foundation was recommended. By using the axis-symmetrical finite element infinite element hybrid method, the sensitivity of mechanical admittance to pile modulus along pile shaft was numerically analyzed, including the effects of the shear wave velocity of subsoil and pile length as well as the defects of pile shaft. The conclusion will be of guide significance on further research of the proposed mechanical admittance method and on the design optimization for dynamic machines with composite foundations. [ABSTRACT FROM AUTHOR]

Based on the dynamic governing equations of elastic waves, a hybrid finite-infinite element method was proposed for analyzing axis-symmetrically vertical vibrations of saturated media. The finite element is to model the near-field solution and the infinite element is used to represent the soil which extends to infinity. The decay functions of the infinite element were derived based on the propagation of waves in saturated media in great details. Using the compiled program, the surface vertical displacements of the air-saturated ground (dry soil) and of the water-saturated stratum with extremely low permeability were calculated under a surface point excitation (called Lamb's problem), which leads to the results agreed very well with the existing theoretical solutions of single-phased elastic media. The proposed method is a simple and reliable numerical method, which has good accuracy and gives large savings in time and expense and can be used to solve the axis-symmetrically dynamic problems of layered saturated media and to get the mechanism of dynamic testing on single piled composite saturated foundation. [ABSTRACT FROM AUTHOR]

Based on the data of vertical and horizontal displacements from a certain construction site in Cixi city of Zhejiang Province, the validity of controlling earth-extrusion effects in saturated soft clay ground caused by statically piling was quantitatively analyzed and compared with different technical measures, including reduction of piling rate and installation of stress relax holes. A preliminary criterion on soil displacement was suggested, which is of use value for reference to eliminate harmful impacts of earth-extrusion effects on the surrounding engineering events at a geologically similar fields. [ABSTRACT FROM AUTHOR]

Abstract: Several soil samples were used to study how the characteristics of natural organic matter (NOM) affect sorption of organic compounds. These soils contains different amounts and types of NOM. Aromaticity of NOM (percentage of aromatic carbons) was determined from solid-state CPMAS [sup 13]C NMR spectra and the soil effective polarity was computed from the equation developed by Xing et al. Naphthalene was used to examine the sorption characteristics of NOM. Both aromaticity and polarity of NOM strongly affected sorption of naphthalene. Old NOM showed higher affinity than that in the surface, young soils. Sorption increased with increasing aromaticity and decreasing polarity. Thus, the sorption coefficients of organic contaminants cannot be accurately predicted without some consideration of NOM characteristics. [ABSTRACT FROM AUTHOR]

Excessive K + efflux via activated voltage-gated K + channels can deplete intracellular K + and lead to long-lasting membrane depolarization which will promote neuronal apoptosis during ischemia/hypoxia injury. The Kv2.1 potassium channel was the major component of delayed rectifier potassium current (Ik) in pyramidal neurons in cortex and hippocampus. The neuronal protective effect of propofol has been proved. Delayed rectifier potassium current (Ik) has been shown to have close relationship with neuronal damage. The study was designed to test the inhibitory effect of propofol on Kv2.1 potassium channel in rat parietal cortical neurons. Whole-cell patch clamp recordings and Western blot analysis were used to investigate the electrophysiological function and protein expression of Kv2.1 in rat parietal cortical neurons after propofol treatment. We found that propofol concentration-dependently inhibited Ik in pyramidal neurons. Propofol also caused a downward shift of the I–V curve of Ik at 30 μM concentration. Propofol significantly inhibited the expression of Kv2.1 protein level at 30 μM, 50 μM, 100 μM concentration. In conclusion, our data showed that propofol could inhibit Ik, probably via depressing the expression of Kv2.1 protein in rat cerebral parietal cortical neurons. [ABSTRACT FROM AUTHOR]

Objective: To explore the related risk factors of hemorrhage in human brain cerebral arteriovenous malformations (AVM) and the relationship between endothelial progenitor cells (EPCs) content and stromal cell-derived factor-1 (SDF-1) in different ages., Methods: A retrospective analysis was conducted on 130 patients with cerebral AVM who underwent surgical treatment from May 2012 to October 2018. Univariate and multivariate logistic analysis was used to investigate the related risk factors of cerebral AVM hemorrhage. Forty paraffin specimens of human brain AVM were harvested from 24 cases of cerebral hemorrhage patients and 16 cases of non-cerebral hemorrhage patients Paraffin samples of cerebral cortex from 8 patients with epilepsy during the same period were selected as control. Positive expression of CD34 and vascular endothelial growth factor receptor 2 (KDR2) in brain tissue samples of both groups were used to identify EPCs. Immunofluorescence double staining was used for KDR2 and CD34 positive localization to determine EPCs localization, and SDF-1 expression detection was performed., Results: The size of brain AVM<3 cm, deep brain AVM and single venous drainage are independent risk factors for cerebral AVM hemorrhage. Immunohistochemical results showed that CD34 and KDR2 were expressed in cerebral AVM group, but not in the control group. Double immunofluorescence staining showed that EPCs mainly existed at the edge of vascular wall, while SDF-1 could co-stain with alpha-smooth muscle actin (α-SMA) positive cells and CD31 positive cells. SDF-1 expression in brain AVM tissue was higher than that in control group. There were significant differences in the number of EPCs among the patients of different ages ( P <0.05). There was no significant difference in EPCs between cerebral hemorrhage group and non-hemorrhage group ( P >0.05)., Conclusion: Brain AVM (<3 cm), single venous drainage and deep brain AVM are independent risk factors for cerebral AVM hemorrhage. In human brain AVM, EPC appears high level but decrease with age, which may play a role in vascular remodeling in AVM., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Science Edition).)

The present study was performed to investigate the effect of retinoic acid amide (RAA) on the expression of integrin α3β1, rate of cell proliferation and migration in p53-deficient glioma cell line, LN-308. The results revealed promotion of integrin α3 expression, reduction in proliferation and migration in RAA treated cells compared to the control LN-308 glioma cells. Promotion of RAA induced integrin α3β1 expression led to the enhancement in cyclin-dependent kinase nuclear localization and activation of Akt pathway. In addition, RAA treatment inhibited the expression of nuclear factor-κB, Bcl-2 and epidermal growth factor receptor (EGFR). These factors are responsible for promoting the rate of cell proliferation and survival in the carcinoma cells. Thus RAA treatment inhibits rate of LN-308 glioma cell proliferation and migration through increase in integrin α3β1 expression and activation of Akt pathway. Therefore, RAA can be of therapeutic importance for the treatment of glioma.

The catalytic cyclocondensation of in situ activated α,β-unsaturated carboxylic acids was developed. N-heterocyclic carbenes efficiently catalyzed the generation of α,β-unsaturated acyl azolium intermediates from α,β-unsaturated carboxylic acids via in situ generated mixed anhydrides for the enantioselective [3+2] and [3+3] cyclocondensation with α-amino ketones and alkyl(aryl)imines, respectively. The corresponding pyrrolidinones and dihydropyridinones were isolated in good yields with high to excellent enantioselectivities., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To explore the effect of puerarin injection on the amount of GLUT4 protein at the plasma membrane in insulin-resistant rat skeletal muscle., Method: The rat model of insulin resistance (IR) was made by being fed with high-fat diet. The animals were divided into three groups (ten in each group): group I: controls; group II: Insulin-resistant rats; group III: Insulin-resistant rats + Puerarin treatment. Insulin-resistant rats were injected with 100 mg puerarin injection per kg body weight through abdominal cavity once a day for 4 weeks. Fasting blood glucose and fasting serum insulin levels were measured before and after Puerarin treatment, respectively. Insulin treatment was achieved by intraperitoneal injection of insulin (1 unit insulin per kg body weight.) 15 minute before killing the animals. The right hindlimb skeletal muscle was rapidly dissected. Then the expression of GLUT4 protein at the plasma membrane in all the animals was assessed with Western blot method., Result: The GLUT4 content at the plasma membrane in insulin-resistant rats skeletal muscle was significantly lower (about 31%) than that of controls (P < 0.01). Puerarin Injection partly corrected fasting blood glucose (from 6.17 +/- 0.67 mmol x L(-1) to 5.54 +/- 0.35 mmol x L(-1)) and fasting serum insulin levels (from 17.09 +/- 2.02 mU x L(-1) to 11.86 +/- 1.35 mU x L(-1)) and increased the GLUT4 content at the plasma membrane by 1.18-fold in insulin-resistant rats skeletal muscle., Conclusion: Puerarin Injection can ameliorate IR, and the mechanism may be involved in increasing cell-surface level of GLUT4 through decreasing fasting blood glucose and fasting serum insulin levels, improving GLUT4 trafficking and intracellular insulin signaling.