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1.
Chemosphere ; 274: 129722, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33540320

RESUMO

Based on the difficulty of the refractory organic compounds degradation in water by the traditional wastewater treatment methods, the research relies on the technology of the dielectric barrier discharge plasma (DBDP) and the catalysis of the nano WO3, investigating the bisphenol A (BPA) degradation in the synergistic system of DBDP/WO3. The coupled degradation percentage of the BPA under different amounts of WO3 addition, different initial solution pH and carrier gas were investigated to confirm the catalysis of the WO3 in the DBDP system. It was obtained from the experimental results that the optimal additive amount of the WO3 was 175 mg L-1 and change of the solution pH value and the carrier gas variety could not change the catalysis of the WO3. The BPA degradation percentage could reach 100% after treating 30 min in the DBDP/WO3 system with 0.5 L min-1 O2 as the carrier gas. The WO3 still had a better catalysis after four times usage and the discharge had little effect on the microstructure of the WO3. The existence of the WO3 in the DBDP system could result in the reduction of the O3 concentration and the enhancement of the H2O2 concentration, which improve the catalysis of the WO3 in the DBDP system, while the experiments on the scavengers' addition verified the major role of the OH on the BPA degradation. The catalytic mechanism of the WO3 as well as the BPA degradation pathway was also speculated in the research.

2.
Inorg Chem ; 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33570384

RESUMO

Pillar[n]arene-based supramolecular polymers have attracted great interest because of their tunable morphologies and external stimuli responsiveness. However, most of the investigations of supramolecular polymers previously reported were focused on their formation and transformation, and investigations on their applications are rare. Herein, we designed and prepared hybrid polymeric materials by incorporating Pd nanoparticles into a supramolecular polymer, constructed from a pillar[5]arene dimer and a three-arm guest. The obtained hybrid polymer was fully characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, scanning electron microscopy-energy-dispersive X-ray mapping, and X-ray diffraction technologies. Importantly, the hybrid supramolecular polymeric materials exhibited desirable catalytic activity for reductions of toxic nitroaromatics and C-C bond-forming Suzuki-Miyaura reaction in aqueous solution.

3.
Plant Biotechnol J ; 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33539631

RESUMO

Artemisinin, a sesquiterpene lactone widely used in malaria treatment, was discovered in the medicinal plant Artemisia annua. The biosynthesis of artemisinin is efficiently regulated by jasmonate (JA) and abscisic acid (ABA) via regulatory factors. However, the mechanisms linking JA and ABA signalling with artemisinin biosynthesis through an associated regulatory network of downstream transcription factors (TFs) remain enigmatic. Here we report AaTCP15, a JA and ABA dual-responsive teosinte branched1/cycloidea/proliferating (TCP) TF, which is essential for JA and ABA-induced artemisinin biosynthesis by directly binding to and activating the promoters of DBR2 and ALDH1, two genes encoding enzymes for artemisinin biosynthesis. Furthermore, AaORA, another positive regulator of artemisinin biosynthesis responds to JA and ABA, interacts with and enhances the transactivation activity of AaTCP15 and simultaneously activates AaTCP15 transcripts. Hence, they form an AaORA-AaTCP15 module to synergistically activate DBR2, a crucial gene for artemisinin biosynthesis. More importantly, AaTCP15 expression is activated by the multiple reported JA and ABA-responsive TFs that promote artemisinin biosynthesis. Among them, AaGSW1 acts at the nexus of JA and ABA signalling to activate the artemisinin biosynthetic pathway and directly binds to and activates the AaTCP15 promoter apart from the AaORA promoter, which further facilitates formation of the AaGSW1-AaTCP15/AaORA regulatory module to integrate JA and ABA-mediated artemisinin biosynthesis. Our results establish a multilayer regulatory network of the AaGSW1-AaTCP15/AaORA module to regulate artemisinin biosynthesis through JA and ABA signalling, and provide an interesting avenue for future research exploring the special transcriptional regulation module of TCP genes associated with specialized metabolites in plants.

4.
Parkinsonism Relat Disord ; 84: 29-34, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33548880

RESUMO

INTRODUCTION: A recent study reported that rare variants in NUS1 were associated with Parkinson's disease (PD). We aimed to assess the relative contribution of rare and common coding/non-coding variants of NUS1 to late-onset PD patients (LOPD). METHODS: Whole genome sequencing data were analyzed for target NUS1 regions, derived from a cohort of 1962 cases and 1279 controls. The genetic association analyses were performed using logistic regression analysis and Sequence Kernel association test. Expression quantitative trait loci (eQTL) analysis was conducted to further explore the association of variants with NUS1 expression based on the data from GTEx database. RESULTS: We identified 18 rare coding variants. p.Y131C was first identified in LOPD. However, no significant burden of rare NUS1 coding variants in LOPD was found. The rare variant sets of two regulatory elements (GH06J117605 and GH06J117674) were significantly enriched in LOPD even after Bonferroni correction (adjusted P = 0.013; adjusted P = 0.010). Considering the joint effect of rare and common variants, all variant sets within GH06J117605 and GH06J117674 showed association with LOPD but were no longer significant after Bonferroni correction. None of the common variants within coding/non-coding regions were significant after Bonferroni correction. The eQTL results suggested these variants in GH06J117605 and GH06J117674 could potentially have eQTL effects on the brain tissues. CONCLUSIONS: These findings provide novel insight into the role of NUS1 regulatory regions in the development of LOPD and indicate that the variants in regulatory elements of NUS1 may be associated with LOPD by influencing the gene expression level.

5.
Int J Cardiol ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33571559

RESUMO

BACKGROUND: Rare genetic variants play a critical role in unprovoked pulmonary embolism (PE). However, the known risk genes only account a small proportion of patients with PE. The objective of this study was to investigate the relationship between the rare variants of gene encoding methylenetetrahydrofolate reductase (MTHFR) and the initiation and long-term clinical outcomes of PE. METHODS: The rare variants of MTHFR were detected by whole exome sequencing of DNA from 258 unprovoked PE cases and 11,451 controls. Correlation of genotype and clinical phenotype and outcome were evaluated at baseline and after follow-up. RESULTS: MTHFR rare variants were found in 15 of 258 cases (5.81%) and 241 of 11,451 controls (2.10%), conferring 2.87-fold greater odds of the PE occurrence (OR = 2.87, 95% CI = 1.68-4.91, P = 5.6 × 10-5, chi-square test). The patients with MTHFR rare variants had higher plasma level of homocysteine than those without. During a follow-up of 3.0 years, a total of 84 events were identified. The recurrent PE (two or more events of PE) were significantly higher in patients carrying MTHFR rare variants (8/15, 53.3%) compared with those without (55/239, 23.0%) (P = 0.023). CONCLUSION: We speculate that MTHFR rare variants may increase the occurrence and recurrence of PE.

6.
Arthroscopy ; 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33539982

RESUMO

PURPOSE: The purpose of the present study was to analyze the anatomical landmarks of Schöttle's Point and establish a locating method for identification. METHODS: From 2013 to 2016, the patients undergoing MPFL reconstruction for patellofemoral instability were enrolled. INCLUSION CRITERIA: at least 2 episodes of patellar dislocation. EXCLUSION CRITERIA: previous knee surgeries, open physes, severe trochlear dysplasia, tibial tuberosity lateralization or patella alta. Group A: From January 2013 to December 2013, preoperative 3D-CT images were obtained. Anatomical features of Schöttle's point were measured on the 3D-CT images. A Schöttle's point locating method with two distinct landmarks was established. Group B: From January 2014 to January 2016, consecutive MPFL reconstructions were performed. The placement of Schöttle's point was following the established method without fluoroscopy. The accuracy of femoral tunnel positions was assessed on the 3D-CT images postoperatively. RESULTS: CT images of 53 knees were obtained in Group A. 47 MPFL reconstructions were performed in Group B. No significant difference was found between the two groups regarding to demographic characteristics. The intra-class correlation coefficients were excellent for all measures (r = 0.97). In group A, the Schöttle's point was 8.1±0.2 mm (95% CI 7.7-8.5) distal to the apex of adductor tubercle and 8.0±0.3 mm (95% CI 7.4-8.6) anterior to the posterior edge. Apex of adductor tubercle was defined as the most convex point, and posterior edge was defined as the edge of posteromedial cortex in transition area between medial condyle and femoral shaft. In group B, 44 of 47 femoral tunnels (93.6%) were considered to be localized in the proper zone. CONCLUSION: The Schottle's point was approximately 8 mm distal to the apex of adductor tubercle and 8 mm from the posterior edge. The Schottle's point locating method without fluoroscopy had high accuracy.

7.
J Mol Model ; 27(3): 79, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560472

RESUMO

UV-vis spectra of azobenzene containing carboxyl group were investigated by using density functional theory calculations. The calculation results show that substitutions of carboxyl groups have no obvious effect on the coplanarity of azobenzene. Compared with azobenzene, the wavelength of maximum absorption of P-COOH-trans has obvious red shift and the wavelength of maximum absorption of M-COOH-trans has blue shift in UV-vis spectra. In addition, P-COOH and M-COOH were synthesized, and their structures were determined by Fourier transform infrared(FT-IR),and their UV-vis spectra. The calculation results are in good agreement with the experimental data.

8.
Am J Manag Care ; 27(2): e36-e41, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577159

RESUMO

OBJECTIVES: This study aimed to evaluate factors affecting adherence to inhaled therapy in patients with asthma to further identify the determinants most closely associated with adherence to inhaled therapy for asthma, especially inhaled glucocorticosteroids (ICS). STUDY DESIGN: A 2-stage study was conducted. In stage 1, we performed nonassumptive deep-dive qualitative scoping to investigate the determinants of poor adherence in patients with asthma, and in stage 2 we developed a new questionnaire for cross-sectional surveys to obtain more accurate information about critical issues related to asthma management. METHODS: Patients with asthma who were 18 years and older in the outpatient clinic of The First Affiliated Hospital of Xi'an Jiaotong University from November 2016 to January 2018 were investigated. RESULTS: In the 350 patients with asthma recruited, 32% of patients showed good adherence, whereas 68% of patients displayed poor adherence to inhaled therapy due to various reasons. Further analysis indicated that inadequate understanding of asthma treatment and control, poor self-management, financial burden, adverse reactions, and the fear of potential adverse reactions were significant independent risk factors for poor ICS inhalation adherence in patients with asthma. CONCLUSIONS: Our research shows that many patients with asthma in western China have poor disease control and poor inhalation therapy adherence. We hope this research can alert clinicians and help them identify patients who may be experiencing uncontrolled asthma due to poor adherence to inhaled therapy, and we suggest that clinicians help those patients obtain appropriate information about asthma control and self-management.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33512043

RESUMO

Formic acid (HCOOH) is one of the most promising chemical fuels that can be produced through CO 2 electroreduction. However, most of the catalysts for CO 2 electroreduction to HCOOH in aqueous solution often suffer from low curkrent density and limited production rate. Herein, we provide a bismuth/cerium oxide (Bi/CeO x ) catalyst, which exhibits not only robust current density (105 mA·cm -2 ), but also unprecedented production rate (2600 µmol·h -1 ·cm -2 ) with high Faradaic efficiency (FE, 92%) for HCOOH generation in aqueous media. Furthermore, Bi/CeO x also shows favorable stability over 34 h. We hope this work could offer an attractive and promising strategy to develop efficient catalysts for CO 2 electroreduction with superior activity and desirable stability.Formic acid (HCOOH) is one of the most promising chemical fuels that can be produced through CO 2 electroreduction. However, most of the catalysts for CO 2 electroreduction to HCOOH in aqueous solution often suffer from low curkrent density and limited production rate. Herein, we provide a bismuth/cerium oxide (Bi/CeO x ) catalyst, which exhibits not only robust current density (105 mA·cm -2 ), but also unprecedented production rate (2600 µmol·h -1 ·cm -2 ) with high Faradaic efficiency (FE, 92%) for HCOOH generation in aqueous media. Furthermore, Bi/CeO x also shows favorable stability over 34 h. We hope this work could offer an attractive and promising strategy to develop efficient catalysts for CO 2 electroreduction with superior activity and desirable stability.

10.
Mol Ther ; 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33429082

RESUMO

It is reported that microRNAs (miRNAs) play an important role in various human diseases. However, the mechanisms of miRNA in these diseases have not been fully understood. Therefore, detecting potential miRNA-disease associations has far-reaching significance for pathological development and the diagnosis and treatment of complex diseases. In this study, we propose a novel diffusion-based computational method, DF-MDA, for predicting miRNA-disease association based on the assumption that molecules are related to each other in human physiological processes. Specifically, we first construct a heterogeneous network by integrating various known associations among miRNAs, diseases, proteins, long non-coding RNAs (lncRNAs), and drugs. Then, more representative features are extracted through a diffusion-based machine-learning method. Finally, the Random Forest classifier is adopted to classify miRNA-disease associations. In the 5-fold cross-validation experiment, the proposed model obtained the average area under the curve (AUC) of 0.9321 on the HMDD v3.0 dataset. To further verify the prediction performance of the proposed model, DF-MDA was applied in three significant human diseases, including lymphoma, lung neoplasms, and colon neoplasms. As a result, 47, 46, and 47 out of top 50 predictions were validated by independent databases. These experimental results demonstrated that DF-MDA is a reliable and efficient method for predicting potential miRNA-disease associations.

11.
Food Chem Toxicol ; 149: 111978, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33428987

RESUMO

Phenolic acids can improve obesity-related and metabolic syndrome-related conditions including non-alcoholic fatty liver disease (NAFLD). In this study, the effects of ferulic acid (FA) on the metabolic changes related to NAFLD were investigated in oleic acid (OA)-treated HepG2 cells and C57BL/6 mice fed a high fat diet (HFD). In vitro, FA (25 and 50 µg/mL) treatment significantly reduced cellular lipid accumulation with no obvious cytotoxicity, in-part mediated by the suppression of ERK1/2, JNK1/2/3, and HGMB1 expression. However, in vivo administration of FA (20 mg/kg bw·day) for 17 weeks led to no obvious effects on body weight and liver weight gain, blood lipid profiles, or histological abnormalities in obese C57BL/6 mice induced by HFD. Taken together, the positive effects of FA on the reduction of hepatic triglyceride accumulation were therefore demonstrated in cellular model, while its hepatic protective effects might need to be further explored in rodent models and clinical trials.

13.
Sensors (Basel) ; 21(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33429947

RESUMO

The plane wave compounding (PWC) is a promising modality to improve the imaging quality and maintain the high frame rate for ultrafast ultrasound imaging. In this paper, a novel beamforming method is proposed to achieve higher resolution and contrast with low complexity. A minimum variance (MV) weight calculated by the partial generalized sidelobe canceler is adopted to beamform the receiving array signals. The dimension reduction technique is introduced to project the data into lower dimensional space, which also contributes to a large subarray length. Estimation of multi-wave receiving covariance matrix is performed and then utilized to determine only one weight. Afterwards, a fast second-order reformulation of the delay multiply and sum (DMAS) is developed as nonlinear compounding to composite the beamforming output of multiple transmissions. Simulations, phantom, in vivo, and robustness experiments were carried out to evaluate the performance of the proposed method. Compared with the delay and sum (DAS) beamformer, the proposed method achieved 86.3% narrower main lobe width and 112% higher contrast ratio in simulations. The robustness to the channel noise of the proposed method is effectively enhanced at the same time. Furthermore, it maintains a linear computational complexity, which means that it has the potential to be implemented for real-time response.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33397703

RESUMO

The bacterial hydrolytic dehalogenation of 4-chlorobenzoate (4CBA) is a CoA-activation type catabolic pathway that is usually a common part of the microbial mineralization of chlorinated aromatic compounds. Previous studies have shown that the transport and dehalogenation genes for 4CBA are typically clustered as an fcbBAT1T2T3C operon and are inducibly expressed in response to 4CBA. However, the associated molecular mechanism remains unknown. In this study, a gene (fcbR) adjacent to the fcb operon was predicted to encode a TetR-type transcriptional regulator in strain Comamonas sediminis CD-2. The fcbR knockout strain exhibited constitutive expression of the fcb cluster. In the host E. coli, the expression of the Pfcb -fused gfp reporter was repressed by the introduction of the fcbR gene, and genetic studies combining various catabolic genes suggest that the FcbR ligand may be an intermediate metabolite. Purified FcbR could bind to the Pfcb DNA probe in vitro, and the metabolite 4-chlorobenzyl-CoA (4CBA-CoA) prevented FcbR binding to the Pfcb DNA probe. Isothermal titration calorimetry (ITC) measurements showed that 4CBA-CoA could bind to FcbR at a 1:1 mole ratio. DNase I footprinting showed that FcbR protected a 42-bp DNA motif (5'-GGAAATCAATAGGTCCATAGAAAATCTATTGACTAATCGAAT-3') that consists of two sequence repeats containing four pseudo-palindromic sequences (5'-TCNATNGA-3'). This binding motif overlaps with the -35 box of Pfcb and was proposed to prevent the binding of RNA polymerase. This study identified a transcriptional repressor and its ligand of the fcb operon, extending halogenated benzoyl-CoA as a member of known ligands of transcriptional regulators.Importance The bacterial hydrolytic dehalogenation of 4CBA is a special CoA-activation type catabolic pathway, which plays an important role in the biodegradation of polychlorinated biphenyls and many certain herbicides. With genetic and biochemical approaches, the present study identified the transcriptional repressor and its cognate effector of a 4CBA hydrolytic dehalogenation operon. This work extends halogenated benzoyl-CoA as a new member of CoA-derived effector compounds that mediate allosteric regulation of transcriptional regulators.

15.
Vet Microbiol ; 253: 108951, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33373884

RESUMO

Brucella, a facultative intracellular bacterium, can survive and replicate in various cell types such as epithelial cell, fibroblasts and macrophage. Macrophage is the most important sites for the survival of Brucella in vivo. The mechanisms of pathogenesis are difficult to address, since the unknown virulence genes are still exist. RNA-seq is available to study transcriptional changes that occur during disease as a way to identify important virulence-related genes. Here we described and analyzed the transcriptional change of avirulent strain Brucella melitensis M5-90 (B. melitensis M5-90) during macrophage infection using RNA-seq technology. We detected 601 significant changed genes of which 428 were upregulated after infection. The upregulated gene L31 which involved in ribosome KEGG pathway was selected to illustrate its effect on virulence in a vaccine strain B. melitensis M5-90 and a virulent strain B. melitensis M28. Deletion of L31 significant attenuates the spleen colonization in model of M5-90 or M28 infection mouse at 7, 21 and 35 days post-infection (P < 0.05). We further examine the role of L31 in a macrophage cell infection model, and the result showed a significant reduction of intracellular M28ΔL31 cells at 48 h post-infection (P < 0.001). In total, our study provided a view of transcriptional landscape of B. melitensis M5-90 intracellular, and found L31 gene is required for the full virulence of B. melitensis.

16.
Clin Chim Acta ; 513: 1-5, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309798

RESUMO

BACKGROUND: Oxidative stress has a key role in brain injury and melatonin possesses antioxidant effects. We aimed to ascertain the potential relationship between serum melatonin concentrations and functional outcome following aneurysmal subarachnoid hemorrhage (aSAH). METHODS: This prospective and observational study was conducted of 169 aSAH patients. Baseline serum melatonin concentrations were determined. A worse 6-month functional outcome was defined as a Glasgow Outcome Scale score of 1-3. RESULTS: Patients with a worse outcome (56 cases) compared to those with a good outcome (113 cases) exhibited significantly higher concentrations of serum melatonin (P < 0.001). An area under the receiver operating curve of 0.819 was revealed for the prediction of 6-month worse outcome by serum melatonin concentrations. Multiple logistic regression analysis showed an independent association of serum melatonin concentrations with 6-month worse outcome (odds ratio = 1.204). An intimate correlation existed between serum melatonin concentrations and World Federation of Neurological Surgeons subarachnoid hemorrhage scale scores as well as between serum melatonin concentrations and modified Fisher scores (P < 0.001). CONCLUSIONS: Patients with higher serum melatonin concentrations are more likely to have a poor prognosis. Serum melatonin can be considered as an independent predictor of functional outcome after aSAH.

17.
Cancer Lett ; 497: 212-220, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33132120

RESUMO

Stress conditions induced by routine treatments might affect cancer-associated fibroblasts in lung adenocarcinoma. The present study tried to explore transcriptome changes in lung fibroblasts under chemotherapeutics, irradiation, and hypoxia, which were induced by chemotherapy, radiotherapy, and anti-angiogenesis therapy, respectively. We established three in vitro models to mimic the stress conditions for lung fibroblasts. Interestingly, one of the secretory molecules, tumor necrosis factor superfamily member 4 (TNFSF4, also known as OX40L), was significantly up-regulated in lung fibroblasts under stress environments. Lung adenocarcinoma patients received chemotherapy and radiotherapy had a higher expression level of TNFSF4 in serum and tumor tissues. There was a negative correlation between the increase of serum TNFSF4 levels and the shrink of the tumor after chemotherapy. TNFSF4 could promote cisplatin resistance and inhibit the apoptosis of lung adenocarcinoma cells. Furthermore, TNFSF4 could significantly increase the activity of NF-κB/BCL-XL pathway in lung adenocarcinoma cells, which could be counteracted by knocking down the expression of TNFRSF4 (receptor of TNFSF4). In conclusion, TNFSF4, secreted by cancer-associated fibroblasts under stress conditions, could facilitate chemoresistance of lung adenocarcinoma through inhibiting apoptosis of tumor cells.

18.
Chemosphere ; 262: 128073, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182155

RESUMO

Due to the multi-catalysis of the WO3 and excellent properties of the graphene (GO), a series of rGO-WO3 nanocomposites were prepared through the hydrothermal synthesis procedure by changing the material ratio, the reaction temperature and the reaction time in this paper, and then added it into a dielectric barrier discharge plasma (DBDP) system for investigating the bisphenol A (BPA)'s degradation and corresponding catalytic mechanism of the rGO-WO3 in the DBDP system. The obtained results show that there was an optimum dosage of the rGO-WO3 (40 mg/L) as well as the preparation conditions (5:1000 mass ratio of the GO and the WO3, 18 h reaction time and 120 °C reaction temperature) for achieving the highest catalytic effect, and the highest degradation rate constant of the BPA was 0.03129 min-1. The determined higher TOC removal, higher COD removal as well as UV-Vis analysis also demonstrated the catalysis of the rGO-WO3. The measurement of the change of the O3 and the H2O2 concentrations in the reaction system with or without the rGO-WO3 and with or without the BPA proved the catalysis of the rGO-WO3 on the ·OH formation, while the combination of the GO had the positive effect for enhancing the catalytic effect. A figure on the catalysis and degradation procedure of the BPA in the DBDP/rGO-WO3 system was provided in the paper.


Assuntos
Compostos Benzidrílicos/análise , Grafite/química , Nanocompostos/química , Óxidos/química , Fenóis/análise , Tungstênio/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Peróxido de Hidrogênio/química , Modelos Teóricos , Oxirredução , Ozônio/química
19.
Nanomaterials (Basel) ; 10(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33255968

RESUMO

A low-threshold miniaturized single-mode nanowire laser operating at telecommunication wavelengths was proposed and simulated. The device was constructed by combining a single InGaAs nanowire with a photonic crystal microcavity and asymmetric distributed-Bragg-reflector mirrors. The mode characteristics and threshold properties were calculated using the three-dimensional finite-different time-domain method. Due to the effective subwavelength confinement and strong optical feedback, provided by the photonic crystal microcavity, and distributed-Bragg-reflector mirrors, respectively, the confinement factor, end-facet reflectivity, and quality factor significantly improved. A lowest threshold of ~80 cm-1 and ultra-small cut-off radius of ~40 nm are obtained, reduced by 67%, and 70%, respectively, compared with a traditional nanowire laser. In addition, due to the photonic band gap effect, single-mode lasing is achieved with a high side-mode suppression ratio of >12 dB. By placing several identical nanowires in the photonic crystal with different lattice constants, an on-chip laser array is realized, which is promising in wavelength division multiplexing applications. This work may pave the way for the development of low-threshold miniaturized nanolasers and low-consumption high-density photonic integrated circuits.

20.
Blood Adv ; 4(23): 5958-5965, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33275768

RESUMO

The prevalence and distribution of congenital thrombophilia is still unclear in patients with pulmonary embolism (PE). We aimed to determine the prevalence and clinical characteristics of congenital thrombophilia in PE patients and their subsequent outcomes. A prospective observational study was conducted from May 2013 to June 2018. A total of 436 consecutive patients with PE were enrolled. All patients were tested for protein C, protein S, antithrombin III (ATIII), factor V Leiden, and prothrombin G20210A mutations. The median follow-up duration was ∼800 days (range, 11-1872 days). Congenital thrombophilia was diagnosed in 31 of 436 (7.1%) patients; 12 patients had protein C deficiency (2.8%), 13 had protein S deficiency (3.0%), 5 had ATIII deficiency (1.1%), and 1 had (0.2%) factor V Leiden. Age ≤50 years at the first episode (odds ratio [OR], 5.43; 95% confidence interval [CI], 2.35-13.52; P < .001) and male sex (OR, 2.67; 95% CI, 1.15-6.78; P = .03) were 2 independent predictors of congenital thrombophilia in PE patients. There was no statistically significant difference in the prevalence of congenital thrombophilia between PE patients with and without risk factors (P = .58). We also found no significant difference in the risk of having a composite outcome of death or recurrent venous thromboembolism between patients with and without congenital thrombophilia (hazard ratio, 0.18; 95% CI, 0.02-5.69; P = .08). These results suggest that age and male sex are independently associated with the occurrence of congenital thrombophilia in PE patients but that congenital thrombophilia is not associated with the risk of recurrence or death with anticoagulation therapy.

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