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2.
J Colloid Interface Sci ; 571: 213-221, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32200165

RESUMO

Plenty of power-shaped semiconductor nanomaterials have been used to photocatalytically degrade various pollutant wastewater in beakers, but they are difficult to be applied in the practical wastewater that is flowing in river or pipeline. Thus, the key to photocatalytically degrading the flowing wastewater is to develop flexible large-scale filter-membrane with high photocatalytic activity. To address the issue, with carbon fiber cloth (CFC) as the porous substrate and TiO2/Ag3PO4 as ultraviolet/visible (UV/Vis) responsed components, we reported the in-situ growth of TiO2/Ag3PO4 nanojunctions on CFC as filter-membrane-shaped photocatalyst. The resulting CFC/TiO2/Ag3PO4 is composed of CFC whose surface is decorated with TiO2 nanorods (length: 1 ± 0.5 µm, diameter: 150 ± 50 nm) and Ag3PO4 nanoparticles (diameter: 20-100 nm). CFC/TiO2/Ag3PO4 displays a broad absorption region with two edges (~410 and ~510 nm), owing to the bandgaps of TiO2 and Ag3PO4. Under Vis or UV-Vis light illumination, CFC/TiO2/Ag3PO4 (4 × 4 cm2) can efficiently degrade more phenol (80.6%/89.4%), tetracycline (TC, 91.7%/94.2%), rhodamine B (RhB, 98.4%/99.5%) and acid orange 7 (AO7, 97.6%/98.3%) in the beaker than CFC/TiO2 or CFC/Ag3PO4. Especially, CFC/TiO2/Ag3PO4 (diameter: ~10 cm) as the filter-membrane was used to construct multiple device for degrading the flowing RhB wastewater. The removal efficiency of RhB increases from 19.6% at the 1st pool to 96.8% at the 8th pool. Therefore, this study brings some insights for purifying organic pollutants in static or flowing wastewater by using filter-membrane-shaped photocatalysts.

3.
Nat Commun ; 11(1): 1586, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221307

RESUMO

Topological properties of materials are typically presented in momentum space. Here, we demonstrate a universal mapping of topological singularities from momentum to real space. By exciting Dirac-like cones in photonic honeycomb (pseudospin-1/2) and Lieb (pseudospin-1) lattices with vortex beams of topological charge l, optimally aligned with a given pseudospin state s, we directly observe topological charge conversion that follows the rule l → l + 2s. Although the mapping is observed in photonic lattices where pseudospin-orbit interaction takes place, we generalize the theory to show it is the nontrivial Berry phase winding that accounts for the conversion which persists even in systems where angular momentum is not conserved, unveiling its topological origin. Our results have direct impact on other branches of physics and material sciences beyond the 2D photonic platform: equivalent mapping occurs for 3D topological singularities such as Dirac-Weyl synthetic monopoles, achievable in mechanical, acoustic, or ultracold atomic systems, and even with electron beams.

4.
Thorac Cancer ; 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32222039

RESUMO

BACKGROUND: Subxiphoid uniportal video-assisted thoracoscopic surgery (SVATS) is more technically challenging than intercostal uniportal video-assisted thoracoscopic surgery (UVATS), especially in more complex procedures such as segmentectomy. We therefore aimed to investigate the worthiness of undertaking the more demanding subxiphoid approach in patients who had undergone anatomical segmentectomy for stage IA non-small cell lung cancer (NSCLC). METHODS: A total of 491 patients were included in our study who had undergone anatomical segmentectomy for stage IA non-small cell lung cancer from September 2014 to April 2018. They were divided into two groups; 278 patients in the UVATS group and 213 patients in the SVATS group. Different perioperative variables, postoperative pain, quality of life and cost were analyzed and compared between both groups. RESULTS: The SVATS group showed a significantly longer operative time (P = 0.007) and more operative blood loss than the intercostal group (P = 0.004). There was no significant difference between both groups regarding postoperative drainage, duration of chest tube, postoperative hospital stay, operative conversion or postoperative complications. The SVATS group showed a significantly lower pain score postoperatively (P < 0.001). In addition, the SVATS group showed a significantly better postoperative quality of life score along the first postoperative year (P < 0.001). UVATS segmentectomy appeared to be significantly cheaper than SVATS segmentectomy (P < 0.001). CONCLUSIONS: SVATS segmentectomy for stage IA lung cancer is a safe procedure that is worth proceeding with as it is associated with better postoperative pain and better quality of life in the first postoperative year. Further studies are recommended to evaluate the actual cost-effectiveness of SVATS segmentectomy. KEY POINTS: • Significant findings of the study Subxiphoid uniportal approach for pulmonary segmentectomy is safe and feasible approach. It has better postoperative pain and better quality of life than the uniportal intercostal approach; however, it is more expensive. • What this study adds Subxiphoid uniportal approach for pulmonary segmentectomy gives a better quality of life in Chinese patients than the intercostal approach; however, it is more expensive.

5.
Nano Lett ; 20(3): 1915-1922, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32091911

RESUMO

Electrochromic supercapacitors that can change their appearances according to their charged states are presently attracting significant interest from both academia and industry. Tungsten oxide is often used in electrochromic supercapacitors because it can serve as an active material for both benchmarking electrochromic devices and high-performance supercapacitor electrodes. Despite this, acceptable visual aesthetics in electrochromic supercapacitors have almost never been achieved using tungsten oxide, because, in its pure form, this compound only displays a 1-fold color modulation from transparent to blue. Herein, we defy this trend by reporting the first ever Fabry-Perot (F-P) cavity-type electrochromic supercapacitors based only on a tungsten oxide material. The devices were sensitively changeable according to their charge/discharge states and displayed a wide variety of fantastic patterns consisting of different, vivid colors, with both simple and complex designs being achieved. Our findings suggested a novel direction for the aesthetic design of intelligent, multifunctional electrochemical energy storage devices.

6.
J Am Chem Soc ; 142(5): 2672-2681, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31940193

RESUMO

The coupling nature of thermoelectric properties determines that optimizing the Fermi level is the priority to achieve a net increase in thermoelectric performance. Conventionally, the carrier concentration is used as the reflection of the Fermi level in the band structure. However, carrier concentration strongly depends upon the material's effective mass, leading to that the optimal carrier concentration varies over a large scale for different materials. Herein, inspired by the big data survey, we develop a golden Seebeck coefficient range of 202-230 µV K-1 for thermoelectric semiconductors with lattice thermal conductivity of 0.4-1.5 W m-1 K-1. When the measured Seebeck coefficient reaches this range, the corresponding figure of merit is maximized. Using this approach, we exemplarily analyze the characteristics of n-type Pb1-xBixSe thermoelectric materials. With detailed electron microscopy and property characterizations, the high densities of dislocations and pores are found to be responsible for a low lattice thermal conductivity. Moreover, Bi substitution significantly tunes the Seebeck coefficient in a wide range. As a result, the Seebeck coefficient of ∼ -230 µV K-1 in Pb0.98Bi0.02Se is close to the golden range, leading to a figure of merit beyond 1.5. This finding provides an intuitive metric to determine the optimization extent of thermoelectric performance.

7.
Nat Commun ; 11(1): 302, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949150

RESUMO

Intercalation-based inorganic materials that change their colours upon ion insertion/extraction lay an important foundation for existing electrochromic technology. However, using only such inorganic electrochromic materials, it is very difficult to achieve the utmost goal of full-colour tunability for future electrochromic technology mainly due to the absence of structural flexibility. Herein, we demonstrate an ultracompact asymmetric Fabry-Perot (F-P) nanocavity-type electrochromic device formed by using partially reflective metal tungsten as the current collector and reflector layer simultaneously; this approach enables fairly close matching of the reflections at both interfaces of the WO3 thin layer in device form, inducing a strong interference. Such an interference-enhanced device that is optically manipulated at the nanoscale displays various structural colours before coloration and, further, can change to other colours including blue, red, and yellow by changing the optical indexes (n, k) of the tungsten oxide layer through ion insertion.

8.
Adv Mater ; 32(8): e1905703, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31944453

RESUMO

Due to the nature of their liquid-like behavior and high dimensionless figure of merit, Cu2 X (X = Te, Se, and S)-based thermoelectric materials have attracted extensive attention. The superionicity and Cu disorder at the high temperature can dramatically affect the electronic structure of Cu2 X and in turn result in temperature-dependent carrier-transport properties. Here, the effective strategies in enhancing the thermoelectric performance of Cu2 X-based thermoelectric materials are summarized, in which the proper optimization of carrier concentration and minimization of the lattice thermal conductivity are the main focus. Then, the stabilities, mechanical properties, and module assembly of Cu2 X-based thermoelectric materials are investigated. Finally, the future directions for further improving the energy conversion efficiency of Cu2 X-based thermoelectric materials are highlighted.

9.
J Clin Lab Anal ; : e23200, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31916309

RESUMO

AIM: In the present study, we purposed to determine serum chitinase 3-like 1 (CHI3L1) expression characteristics in chronic liver diseases monoinfected with hepatitis B virus and analyze its diagnostic value in liver fibrosis. METHODS: A total of 467 chronic hepatitis B (CHB) patients, 312 liver cirrhosis (LC) patients, and 104 hepatocellular carcinoma (HCC) patients at our institution were enrolled, and clinical indicators were analyzed. RESULTS: Our data have shown that the expression level of serum CHI3L1 was steadily increased from CHB to LC to HCC (P < .001). Serum CHI3L1 expression levels were positively associated with liver stiffness measurement (LSM), fibrosis-4 (FIB-4) index, aspartate aminotransferase-to-platelet ratio index (APRI), and HCC stage. The receiver operating characteristic (ROC) curve proved that serum CHI3L1 was superior to other noninvasive methods (LSM, FIB-4, and APRI) with an area under the ROC curve (AUC) of 0.97 in diagnosing significant fibrosis. CONCLUSIONS: Serum CHI3L1 harbors significant clinical value in chronic liver diseases infected with hepatitis B virus, especially in the diagnosis of fibrosis.

10.
Adv Mater ; 32(1): e1905025, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31713899

RESUMO

Developing efficient and low-cost electrocatalysts for the oxygen evolution reaction (OER) is of paramount importance to many chemical and energy transformation technologies. The diversity and flexibility of metal oxides offer numerous degrees of freedom for enhancing catalytic activity by tailoring their physicochemical properties, but the active site of current metal oxides for OER is still limited to either metal ions or lattice oxygen. Here, a new complex oxide with unique hexagonal structure consisting of one honeycomb-like network, Ba4 Sr4 (Co0.8 Fe0.2 )4 O15 (hex-BSCF), is reported, demonstrating ultrahigh OER activity because both the tetrahedral Co ions and the octahedral oxygen ions on the surface are active, as confirmed by combined X-ray absorption spectroscopy analysis and theoretical calculations. The bulk hex-BSCF material synthesized by the facile and scalable sol-gel method achieves 10 mA cm-2 at a low overpotential of only 340 mV (and small Tafel slope of 47 mV dec-1 ) in 0.1 m KOH, surpassing most metal oxides ever reported for OER, while maintaining excellent durability. This study opens up a new avenue to dramatically enhancing catalytic activity of metal oxides for other applications through rational design of structures with multiple active sites.

11.
J Nanosci Nanotechnol ; 20(4): 2032-2039, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492209

RESUMO

The chemo-photothermal therapy has been proved to be one of efficient strategies for destroying cancer cells, and the prerequisite is to develop photothermal nanoagents with drug-loading capacity. However, most of the current chemo-photothermal nanoagents have multiple structures which require complex synthetic process, undoubtedly hindering their bioapplication. Herein, we prepared PEGylated Bi nanoparticles and loaded with the model drug doxorubicin (DOX), forming DOX@Bi-PEG nanoparticles. Bi-PEG nanoparticles were firstly synthesized through a rapid reduction method and then coated with PEGylated phospholipids, exhibiting strong NIR absorption, high photothermal conversion efficiency of 49.4%, DOX-loading efficiency of 22.8% as well as low cytotoxicity. After incubation with 4T1 cells, DOX@Bi-PEG nanoparticles can be uptaken by cells and then release DOX within cells for chemotherapy. Furthermore, when exposed to 1064 nm laser, these nanoparticles can produce enough heat for photothermal ablating cancer cells. Therefore, the present DOX@Bi-PEG nanoparticles can be served as novel and efficient nanoagents for chemophotothermal therapy of cancer cells.

12.
J Colloid Interface Sci ; 560: 475-484, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31679776

RESUMO

Ultrathin MoS2 nanosheet hybridized Bi5O7I (MoS2/Bi5O7I) nanorods were synthesized via a reactable ionic liquid assisted solvothermal process for the first time. The photocatalytic activity of MoS2/Bi5O7I nanorods was determined by photodegrading bisphenol A (BPA), tetracycline hydrochloride (TC) and ciprofloxacin (CIP) under visible light irradiation. Experimental results showed that MoS2/Bi5O7I owned the excellent photocatalytic properties and photostability. The efficient visible light driven photocatalytic performance was due to a larger specific surface area of MoS2, which increased the close interfacial contact between pollutants and photocatalysts. Meanwhile, the introduction of ultrathin MoS2 nanosheet was conducive to the separation and utilization of photoinduced charge carriers, thus further suppressed high recombination rate in pure Bi5O7I nanorods. Moreover, a possible charge transfer path in MoS2/Bi5O7I composite material was also put forward.

13.
World J Gastrointest Oncol ; 11(11): 946-956, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31798776

RESUMO

The dependence of tumor growth on neovascularization has become an important aspect of cancer biology. Tumor angiogenesis is one of the key mechanisms of tumorigenesis, growth and metastasis. The key events involved in this process are endothelial cell proliferation, migration, and vascular formation. Recent studies have revealed the importance of tumor-associated endothelial cells (TECs) in the development and progression of colorectal cancer (CRC), including epithelial proliferation, stem cell maintenance, angiogenesis, and immune remodeling. Decades of research have identified that the molecular basis of tumor angiogenesis includes vascular endothelial growth factors (VEGFs) and their receptor family, which are the main targets of antiangiogenesis therapy. VEGFs and their receptors play key roles in the pathology of angiogenesis, and their overexpression indicates poor prognosis in CRC. This article reviews the characteristics of the tumor vasculature and the role of TECs in different stages of CRC and immune remodeling. We also discuss the biological effects of VEGFs and their receptor family as angiogenesis regulators and emphasize the clinical implications of TECs in clinical treatment.

14.
Phys Rev Lett ; 123(23): 234101, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868434

RESUMO

We demonstrate for the first time that the nonlinear response of a medium can be mapped directly onto a dynamical wave profile as governed by a generalized nonlinear Schrödinger equation. As analyzed in an accelerating coordinate, the intrinsic gravitylike potential helps "isolate" the effects related to a strong repulsive nonlinear interaction from the dispersion or diffraction in a steady state. Thus, under appropriate conditions, the associated nonlinear response curve can be read out directly in the profile of the nonlinear state. A simple scheme is proposed to approach adiabatically these modes through a shaped input wave profile. Our analysis is further verified experimentally by directly visualizing a Kerr (saturable) nonlinearity experienced by an optical pulse (beam) in a nonlinear fiber (photorefractive crystal), validating the versatility of this approach for different types of optical nonlinearities.

15.
J Immunol Res ; 2019: 4354786, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886303

RESUMO

Atherosclerosis is the main pathological basis for the occurrence of most cardiovascular diseases, the leading global health threat, and a great burden for society. It has been well established that atherosclerosis is not only a metabolic disorder but also a chronic, sterile, and maladaptive inflammatory process encompassing both innate and adaptive immunity. Macrophages, the major immune cell population in atherosclerotic lesions, have been shown to play critical roles in all stages of atherosclerosis, including the initiation and progression of advanced atherosclerosis. Macrophages have emerged as a novel potential target for antiatherosclerosis therapy. In addition, the macrophage phenotype is greatly influenced by microenvironmental stimuli in the plaques and presents complex heterogeneity. This article reviews the functions of macrophages in different stages of atherosclerosis, as well as the phenotypes and functions of macrophage subsets. New treatment strategies based on macrophage-related inflammation are also discussed.

16.
Aging (Albany NY) ; 11(22): 9982-9999, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772143

RESUMO

This study investigates the role of circular RNA (circRNA) hsa_circ_0000515 in cervical cancer and the underlying mechanism associated with microRNA-326 (miR-326). hsa_circ_0000515 and ETS transcription factor ELK1 (ELK1) were initially over-expressed and miR-326 was down-regulated in cervical cancer tissues and cells. Low hsa_circ_0000515 expression was found to be associated with favorable prognosis of patients with cervical cancer. A series of mimics, inhibitors, over-expression plasmids or siRNAs were introduced into cervical cancer cells to alter the expression of hsa_circ_0000515, miR-326 and ELK1. In vitro experiments exhibited that silencing of hsa_circ_0000515 or upregulation of miR-326 resulted in suppressed proliferation and invasion, along with induced apoptosis and autophagy of cervical cancer cells. Dual-luciferase reporter assay, RNA pull-down and RIP assays highlighted that hsa_circ_0000515 was able to act as a ceRNA of miR-326 to increase ELK1. Furthermore, enhancement of ELK1 expression resulted in enhanced proliferation and invasion but repressed apoptosis and autophagy of cervical cancer cells. In vivo experiments further confirmed the suppressed tumor growth by hsa_circ_0000515 silencing. Our findings demonstrated that hsa_circ_0000515 acts as a tumor promoter in cervical cancer. The study provides evidence for targeting hsa_circ_0000515 for therapeutic purposes in treating cervical cancer.

17.
Neuroimmunomodulation ; 26(5): 258-264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31655825

RESUMO

BACKGROUND AND OBJECTIVE: Plasma homocysteine (Hcy) levels have been investigated among patients with multiple sclerosis (MS). However, the changes in Hcy levels and the association between Hcy levels and inflammatory/immune/cerebrospinal fluid (CSF) parameters in neuromyelitis optica spectrum disorder (NMOSD) patients have not been investigated yet. METHODS: Case data were collected from 97 acute-phase NMOSD patients and 39 stable-phase NMOSD patients. Patients in the acute phase were divided into 2 groups based on the EDSS score with cutoff equal to 4. Hcy levels, immunoglobulins (Ig) A, G, and M, complement 3 and 4, CH50, C-reactive protein, erythrocyte sedimentation rate (ESR), and CSF examination including white blood cells and total protein were determined. RESULTS: No significant differences in Hcy levels are observed between acute-phase and stable-phase NMOSD patients. Hcy and ESR levels were significantly higher in acute-phase NMOSD patients with EDSS score ≥4. Besides, EDSS is positively correlated with Hcy level, ESR, 1/aquaporin-4 titer and Hcy level is negatively correlated with IgM in acute-phase NMOSD patients. CONCLUSION: Elevated plasma Hcy has the potential to affect the pathogenesis or progression of NMOSD.

18.
J Phys Chem Lett ; 10(21): 6512-6517, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31597419

RESUMO

We report a comprehensive in-situ phase-change study on polycrystalline Sn0.98Se via high-temperature X-ray diffraction and in-situ high-voltage transmission electron microscopy from room temperature to 843 K. The results clearly demonstrate a continuous phase transition from Pnma to Cmcm starting from 573 to 843 K, rather than a sudden transition at 800 K. We also find that the thermal-conductivity rise at high temperature after the phase transition, as commonly seen in pristine SnSe, does not occur in Sn0.98Se, leading to a high thermoelectric figure of merit. Density functional theory calculations reveal the origin to be the suppression of bipolar thermal conduction in the Cmcm phase of Sn0.98Se due to the enlarged bandgap. This work fills the gap of in-situ characterization on polycrystalline Sn0.98Se and provides new insights into the outstanding thermoelectric performance of polycrystalline Sn0.98Se.

20.
J Biochem Mol Toxicol ; 33(11): e22397, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31557363

RESUMO

Fumonisins (Fums) are mycotoxins widely distributed in crops and feed, and ingestion of Fums-contaminated crops is harmful to animal health. The purpose of this study is to explore the effect of Fum B1 (FB1 ) on barrier functions of porcine intestinal epithelial cells, IPEC-J2, to clarify the intestinal toxicity of Fums in pigs. The results showed that the persistent treatment of FB1 significantly decreased the viability of IPEC-J2. Moreover, the expressions of Claudin 1, Occludin, Zonula Occluden-1 (ZO-1) on the messenger RNA (mRNA), and protein levels and MUC1 on the mRNA level were significantly inhibited after FB1 treatment, while the mRNA relative expression level of MUC2 was clearly increased. FB1 also enhanced the monolayer cell permeability of IPEC-J2. Importantly, FB1 promoted the expression of phosphorylated extracellular regulated protein kinase (p-ERK1/2 ). These data suggest that long-term treatment of FB1 can suppress IPEC-J2 proliferation, damage tight junctions of IPEC-J2, and regulate expression of mucins to induce the damage of barrier functions of porcine intestinal epithelial cells, which may be associated with the ERK1/2 phosphorylation pathway.


Assuntos
Células Epiteliais/metabolismo , Fumonisinas/farmacologia , Mucosa Intestinal/citologia , Micotoxinas/farmacologia , Permeabilidade/efeitos dos fármacos , Junções Íntimas/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fusarium/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mucina-1/genética , Mucina-1/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Suínos , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo
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