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1.
J Am Chem Soc ; 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35044172

RESUMO

The development of efficient and durable electrocatalysts is the only way to achieve commercial fuel cells. A new, efficient method was utilized for epitaxial growth of gold quantum dots using atomically platinum chlorine species with porous graphdiyne as a support (PtCl2Au(111)/GDY), for obtaining successful multicomponent quantum dots with a size of 2.37 nm. The electrocatalyst showed a high mass activity of 175.64 A mgPt-1 for methanol oxidation reactions (MORs) and 165.35 A mgPt-1 for ethanol oxidation reactions (EORs). The data for this experiment are 85.67 and 246.80 times higher than those of commercial Pt/C, respectively. The catalyst also showed highly robust stability for MORs with negligible specific activity decay after 110 h at 10 mA cm-2. Both structure characterizations and theoretical calculations reveal that the excellent catalytic performance can be ascribed to the chlorine introduced to modify the d-band structure on the Pt surface and suppression of the CO poisoning pathway of the MOR. Our results indicate that an atomically dispersed metal species tailoring strategy opens up a new path for the efficient design of highly active and stable catalysts.

2.
J Cancer Res Ther ; 17(5): 1141-1156, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34850761

RESUMO

The Expert Consensus reviews current literatures and provides clinical practice guidelines for thermal ablation of pulmonary subsolid nodules or ground-glass nodule (GGN). The main contents include the following: (1) clinical evaluation of GGN; (2) procedures, indications, contraindications, outcomes evaluation, and related complications of thermal ablation for GGN; and (3) future development directions.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34854185

RESUMO

The sluggish lithium-ion transport kinetics in anode materials triggers a huge voltage polarization and serious lithium metal plating, greatly restricting the cycling life and energy density of the fast-charging lithium-ion batteries. Here we propose a new idea of self-expanding lithium-ion transport channels to construct a fast-charging anode and realize high-performance fast-charging lithium-ion batteries. The self-expanded lithium-ion transport channels can be enabled by a self-reversible conversion of chemical bonds with different bond lengths in the anode driven by the interactions with lithium ions during cycling, reduce the energy barrier of lithium-ion transport and allow a fast lithium-ion solid-state diffusion, whereby the severe voltage polarization and lithium metal plating are effectively eliminated. Our proof-of-concept demonstration of the self-reversible conversion of chemical bonds on the surface of graphdiyne successfully verifies the self-expanded lithium-ion transport channels, self-accelerated lithium in-plane/out-of-plane migration, and superior fast-charging capability with a high capacity (342 mA h g -1 ) and an ultra-long lifespan (22,000 cycles) under extremely fast-charging conditions (6 C rate, 1 C = 744 mA g -1 ), even at low temperatures (-10 °C). These results represent a platform for designing novel fast-charging anode materials with self-regulatable ion transport channels and significantly enhanced ion solid-state diffusion kinetics.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34799952

RESUMO

Zn dendrite issue was intensively studied via tuning zinc ion flux. pH change seriously influences dendrite formation, while its importance has not been revealed. Here, we construct a N-modification graphdiyne interface (NGI) to stabilize pH by mediating hydrated zinc ion desolvation. Operando pH detection reveals pH stabilization by NGI. This works with pores in NGI to achieve dendrite-free Zn deposition and an increased symmetric cell lifespan by 116 times. Experimental and theoretical results owe pH stabilization to desolvation with a reduced activation energy achieved by electron transfer from solvation sheath to N atom. The efficient desolvation ensures that electron directly transfers from substrate to Zn2+ (rather than the coordinated H2O), avoiding O-H bond splitting. Hence, Zn-V6O13 battery achieves a long lifespan at 20.65 mA cm-2 and 1.07 mAh cm-2. This work reveals the significance of interface pH and provides a new approach to address Zn dendrite issue.

6.
Sci Total Environ ; : 151667, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34793785

RESUMO

The iron (Fe) phases have been widely proposed to preserve organic carbon (OC) via adsorption or coprecipitation pathways, however, such role of Fe phases might be largely reversed under redox-fluctuation conditions, especially for Fe(II) minerals-protected OC. In this study, we synthesized the Fe(II)-OC associations via adsorption and coprecipitation using FeCO3 and three types of low-molecular-weight organic compounds (LMWOCs) at different C/Fe molar ratios, and investigated the OC mineralization induced by hydroxyl radicals (OH) during oxygenation processes. Abundant OH can be produced upon oxygenation of FeCO3-LMWOCs associations within 96 h, giving values of 28.49-151.36 µM in adsorption and 12.63-76.41 µM in coprecipitation treatments depended on types of LMWOCs and C/Fe molar ratios. Fe(II) species in coprecipitates with hydroquinone (HQ) mainly transformed into Goethite-like phases after oxygenation, while adsorption samples induced more formation of lower-crystalline Fe phase (e.g., ferrihydrite). The surface-Fe(II) was the primary electron donors to O2, which further induced hydrogen peroxide (H2O2) formation via one- and two-electron transfer pathways. Finally, the produced OH removed 0.55-9.65 and 0.16-85.54 mg L-1 total OC in adsorption and coprecipitation treatments after oxygenation. Collectively, this study highlights that OC associated with Fe(II) minerals might be labile due to the oxidation of formed OH, and the role of Fe phases in OC sequestration may be further re-evaluated under redox fluctuation conditions.

7.
Adv Sci (Weinh) ; : e2102721, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34747572

RESUMO

An iron vacancy-rich ferroferric oxide/graphdiyne heterostructure (IVR-FO/GDY) is rationally designed and fabricated for high-efficiency electrocatalytic nitrogen fixation to ammonia (ENFA). Experimental and theoretical results show that the GDY-induced iron vacancies in IVR-FO/GDY promote the electrocatalysis, and activate the local O sites to transfer electrons towards GDY to boost ENFA, resulting in promising electrocatalytic performances with a highest ammonia yield (YNH3 ) of 134.02 µg h-1 mgcat. -1 and Faradaic efficiency (FE) of up to 60.88%, as well as the high long-term stability in neutral electrolytes. The cationic vacancy activation strategy proposed in this work has strong general and universal guiding significance to the design of new efficient electrocatalysts for various electrochemical energy conversion reactions. Such defect engineering may be used efficiently in electrocatalysis, leading to the development and progress of energy industry.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34708554

RESUMO

PURPOSE: The optimal microparticle size for drug-eluting beads transarterial chemoembolization (DEB-TACE) remains unknown. This retrospective cohort study analyzed the efficacy and safety of CalliSpheres microsphere embolization in the treatment of unresectable hepatocellular carcinoma (HCC) to determine the influence of particle size on the results. PATIENTS AND METHODS: Forty-two patients with unresectable HCC were enrolled in this retrospective study from January 2018 to January 2020. Patients received DEB-TACE with CalliSpheres of 100-300 µm (small-size, n = 15) or 300-500 µm (medium-size, n = 27). The tumor response was evaluated via enhanced CT or MRI at 1 month, 3 months, and 6 months after treatment, based on the Modified Response Evaluation Criteria in Solid Tumors. Adverse events after DEB-TACE were recorded. RESULTS: Complete response, partial response, stable disease, and progressive disease were recorded in 20%, 20%, 33.3%, 26.7%, respectively, of patients in the small-size group and 3.7%, 25.9%, 44.4%, 25.9% of patients in the medium-size group, respectively. No significant difference was found between the two groups (p = 0.516). Major adverse events, including grade three liver toxicity (n = 4) and liver abscess (n = 3), occurred significantly more in the small-size group, while none were reported in the medium size group (p < 0.05). CONCLUSION: DEB-TACE with medium-size (300-500 µm) CalliSpheres microspheres had similar efficacy and a better safety profile than DEB-TACE with small-size (100-300 µm) CalliSpheres, indicating that medium-size microspheres may be a better choice for unresectable primary liver cancer.

9.
Natl Sci Rev ; 8(8): nwaa213, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34691704

RESUMO

Development of novel catalysts for nitrogen reduction at ambient pressures and temperatures with ultrahigh ammonia (NH3) yield and selectivity is challenging. In this work, an atomic catalyst with separated Pd atoms on graphdiyne (Pd-GDY) was synthesized, which shows fascinating electrocatalytic properties for nitrogen reduction. The catalyst has the highest average NH3 yield of 4.45 ± 0.30 mgNH3 mgPd -1 h-1, almost tens of orders larger than for previously reported catalysts, and 100% reaction selectivity in neutral media. Pd-GDY exhibits almost no decreases in NH3 yield and Faradaic efficiency. Density functional theory calculations show that the reaction pathway prefers to perform at the (Pd, C1, C2) active area because of the strongly coupled (Pd, C1, C2), which elevates the selectivity via enhanced electron transfer. By adjusting the p-d coupling accurately, reduction of self-activated nitrogen is promoted by anchoring atom selection, and side effects are minimized.

10.
Opt Express ; 29(18): 28503-28520, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34614979

RESUMO

The correction of uneven illumination in microscopic image is a basic task in medical imaging. Most of the existing methods are designed for monochrome images. An effective fully convolutional network (FCN) is proposed to directly process color microscopic image in this paper. The proposed method estimates the distribution of illumination information in input image, and then carry out the correction of the corresponding uneven illumination through a feature encoder module, a feature decoder module, and a detail supplement module. In this process, overlapping residual blocks are designed to better transfer the illumination information, and in particular a well-designed weighted loss function ensures that the network can not only correct the illumination but also preserve image details. The proposed method is compared with some related methods on real pathological cell images qualitatively and quantitatively. Experimental results show that our method achieves the excellent performance. The proposed method is also applied to the preprocessing of whole slide imaging (WSI) tiles, which greatly improves the effect of image mosaicking.

11.
Adv Sci (Weinh) ; 8(21): e2102777, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34494718

RESUMO

There is no doubt that hydrogen energy can play significant role in promoting the development and progress of modern society. The utilization of hydrogen energy has developed rapidly, but it is far from the requirement of human. Therefore, it is very urgent to develop methodologies and technologies for efficient hydrogen production, especially high activity and durable electrocatalysts. Here a bimetallic oxide cluster on heterostructure of vanadium ruthenium oxides/graphdiyne (VRuOx /GDY) is reported. The unique acetylene-rich structure of graphdiyne achieves outstanding characteristics of electrocatalyst: i) controlled preparation of catalysts for achieving multiple-metal clusters; ii) regulation of catalyst composition and morphology for synthesizing high-performance catalysts; iii) highly active and durable hydrogen evolution reaction (HER) properties. The optimal porous electrocatalyst (VRu0.027 Ox /GDY) can deliver 10 mA cm-2 at low overpotentials of 13 and 12 mV together with robust long-term stability in alkaline and neutral media, respectively, which are much smaller than Pt/C. The results reveal that the synergism of different components can efficiently facilitate the electron/mass transport properties, reduce the energy barrier, and increase the active site number for high catalytic performances.

12.
Chem Asian J ; 16(21): 3259-3271, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34467664

RESUMO

Two-dimensional (2D) graphdiyne (GDY), a rapidly rising star on the horizon of carbon materials, is a new carbon allotrope featuring sp- and sp2 -cohybridized carbon atoms and 2D one-atom-thick network. Since the first successful synthesis of GDY by Professor Li's group in 2010, GDY has attached great interests from both scientific and industrial viewpoints based on its unique structure and physicochemical properties, which provides a fertile ground for applications in various fields including electrocatalysis, energy conversion, energy storage and optoelectronic devices. In this work, various potential properties of the GDY-based electrocatalysts and their recent advances in energy conversion are reviewed, including atomic catalysts, heterogeneous catalysts, and metal-free catalysts. The critical role of GDY in improving catalytic activity and stability is analyzed. The perspectives of the challenges and opportunities faced by GDY-based materials for energy conversion are also outlined.

13.
Adv Mater ; : e2102811, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34486181

RESUMO

Currently, organic semiconductors (OSs) are widely used as active components in practical devices related to energy storage and conversion, optoelectronics, catalysis, and biological sensors, etc. To satisfy the actual requirements of different types of devices, chemical structure design and self-assembly process control have been synergistically performed. The morphology and other basic properties of multiscale OS components are governed on a broad scale from nanometers to macroscopic micrometers. Herein, the up-to-date design strategies for fabricating multiscale OSs are comprehensively reviewed. Related representative works are introduced, applications in practical devices are discussed, and future research directions are presented. Design strategies combining the advances in organic synthetic chemistry and supramolecular assembly technology perform an integral role in the development of a new generation of multiscale OSs.

14.
Nanoscale ; 13(30): 13072-13084, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34477791

RESUMO

Graphdiyne oxide (GDYO) is a carbon-based nanomaterial possessing sp2 and sp-hybridized carbon atoms with many promising applications. However, its biocompatibility and potential biodegradability remain poorly understood. Using human primary monocyte-derived macrophages as a model we show here that GDYO elicited little or no cytotoxicity toward classically activated (M1) and alternatively activated (M2) macrophages. Moreover, GDYO reprogrammed M2 macrophages towards M1 macrophages, as evidenced by the elevation of specific cell surface markers and cytokines and the induction of NOS2 expression. We could also show inducible nitric oxide synthase (iNOS)-dependent biodegradation of GDYO in M1 macrophages, and this was corroborated in an acellular system using the peroxynitrite donor, SIN-1. Furthermore, GDYO elicited the production of pro-inflammatory cytokines in a biodegradation-dependent manner. Our findings shed new light on the reciprocal interactions between GDYO and human macrophages. This is relevant for biomedical applications of GDYO such as the re-education of tumor-associated macrophages or TAMs.


Assuntos
Grafite , Óxidos , Citocinas , Humanos , Macrófagos , Óxido Nítrico Sintase Tipo II/genética
15.
Small ; 17(38): e2102066, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34365731

RESUMO

Suppressing the irreversible interfacial reactions is an important scientific bottleneck in the development of stable high-energy-density lithium-ion battery. The interfacial chemistry of graphdiyne (GDY) on the high-voltage cathode of LiNi0.5 Mn1.5 O4 (LNMO) shows a very interesting process, in which the sp-hybridization carbon atoms chemically scavenge the hydrofluoric acid (HF) and in situ form the fluorinated GDY interface. It first turns the harmful HF into profit, and greatly enhances the interfacial stability and restrains the side reaction on the cathode under high working voltage. The GDY-coated LNMO cathode obviously alleviates the electrolyte degradation, achieves high Coulombic efficiency and reliability. Due to atomic-level selectivity and chemical trapping of HF by GDY, it effectively suppresses the dissolution of Mn, Ni elements. These results highlight the unparalleled advantages of GDY in the formation of high stable interfaces and protection of high-energy-density electrodes.

16.
Pancreas ; 50(6): 822-826, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34347726

RESUMO

OBJECTIVES: This retrospective cohort study investigated the efficacy of routine intravenous chemotherapy (the control group), transcatheter arterial infusion (TAI) chemotherapy, and TAI combined with radioactive particles as therapeutic methods for advanced body/tail pancreatic cancer by assessing the short-term and overall survival rates. METHODS: We screened our prospective database for patients with advanced body/tail pancreatic cancer, which tumor deemed unresectable, and no other confirmed malignant tumors, patients were assigned into 3 groups according to their treatment: routine intravenous chemotherapy, TAI, and TAI combined with radioactive particles. RESULTS: The median survival time was 6 months in the control group, 10 months in the TAI group, and 13 months in the TAI combined group. The Kaplan-Meier estimates of the overall survival among the 3 groups, indicating that there is significant difference among 3 groups (P < 0.000). The clinical remission rates were 17.5% in the control group, 41.5% in the TAI group, and 48.0% in the TAI combined group. Covariates analyzed showed that different treatment methods and times affected the results significantly (P < 0.002). CONCLUSIONS: In the treatment of advanced body/tail pancreatic cancer, TAI and TAI combined with radioactive particles significantly improved the clinical outcomes in patients compared with routine intravenous chemotherapy.

17.
Chem Sci ; 12(30): 10334-10340, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34377418

RESUMO

Exploring a new-family of carbon-based desalinators to optimize their performances beyond the current commercial benchmark is of significance for the development of practically useful capacitive deionization (CDI) materials. Here, we have fabricated a hierarchically porous N,P-doped carbon-graphene 2D heterostructure (denoted NPC/rGO) by using metal-organic framework (MOF)-nanoparticle-driven assembly on graphene oxide (GO) nanosheets followed by stepwise pyrolysis and phosphorization procedures. The resulting NPC/rGO-based CDI desalinator exhibits ultrahigh deionization performance with a salt adsorption capacity of 39.34 mg g-1 in a 1000 mg L-1 NaCl solution at 1.2 V over 30 min with good cycling stability over 50 cycles. The excellent performance is attributed to the high specific surface area, high conductivity, favorable meso-/microporous structure together with nitrogen and phosphorus heteroatom co-doping, all of which are beneficial for the accommodation of ions and charge transport during the CDI process. More importantly, NPC/rGO exhibits a state-of-the-art CDI performance compared to the commercial benchmark and most of the previously reported carbon materials, highlighting the significance of the MOF nanoparticle-driven assembly strategy and graphene-carbon 2D heterostructures for CDI applications.

18.
Lasers Surg Med ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34463963

RESUMO

OBJECTIVES: Percutaneous treatment of symptomatic cholelithiasis with large gallstones remains a challenge. We aimed to evaluate the efficacy and safety of a new method for the removal of giant gallstones with percutaneous lithotripsy using a frequency-doubled double-pulse neodymium: YAG (FREDDY) laser. MATERIALS AND METHODS: This study included 16 patients (7 males, 9 females; mean age, 63.4 ± 14.9 years) with giant gallstones who experienced the recurrence of cholecystitis and were not eligible for operation. The percutaneous transcystic approach was established using an 8-French sheath. A 6-French steerable sheath were inserted through the sheath. FREDDY laser lithotripsy was performed to break the stones into fragments. The stone fragments were extracted through the 6-French sheath or pushed into the duodenum using a balloon catheter. Cholecystography was performed before removing the catheter. Follow-up ultrasound or computed tomography examination were performed. RESULTS: Gallstone clearance was accomplished in 16 (100%) patients at the initial assessment. Eleven patients underwent one session, and five patients underwent two sessions. Residual stones were found in 3 (18.8%) patients during the follow-up period. Peritonitis was found in two (12.5%) patients and hemocholecyst was detected in one (6.3%) patient. No procedure-related deaths occurred. CONCLUSION: Percutaneous lithotripsy using a FREDDY laser may be an effective and safe alternative choice for treating giant gallstones, especially for patients who are not eligible for cholecystectomy.

19.
Nano Lett ; 21(14): 6005-6013, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34242035

RESUMO

Nanomaterial-biology interaction is the critical step in the fate of biomedical nanomedicines, influencing the consequent biological outcomes. Herein, we present two-dimensional carbon-based nanomaterials-graphdiyne oxide (GDYO) nanosheets that interact with an intracellular protein corona consisting of signal transducer and activator of transcription 3 (STAT3), inducing the reeducation of immunosuppressive macrophages. The interaction at the GDYO-STAT3 interface, driven by structure matching, hydrogen bonding, and salt bridges, simultaneously triggers the immune response in the tumor microenvironment, facilitating cancer immunotherapy. For the first time, our data reveal an interaction mechanism between the nanoparticle-protein interfaces inevitably formed inside the cells that determines the macrophage phenotype. Our results suggest that GDYO nanosheets could be applied for local immunomodulation due to their function and structural organization of the intracellular protein corona occurred inside macrophages.


Assuntos
Coroa de Proteína , Grafite , Imunidade , Imunomodulação , Óxidos
20.
Thorac Cancer ; 12(17): 2352-2359, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34255431

RESUMO

BACKGROUND: In our previous study, we indicated that scutellarin (SCU) induced an anticancer effect in A549 cells. However, whether SCU regulates the radiosensitivity of non-small cell lung cancer (NSCLC) and its related mechanism is still unclear. METHODS: In this study, we explored the anticancer effect induced by iodine-125 (125 I) and SCU at a sensitizing concentration in A549 and H1975 cells. Cellular apoptosis and proliferation were detected by flow cytometry, Bcl-2/Bax expression level, cell cycle, CCK-8, and EdU staining. A tumor model using nude mice was also carried out to investigate the combined effect of 125 I and SCU in vivo. In addition, the expression level of AKT/mTOR pathway was detected to investigate whether it is linked to the anticancer effect of 125 I and SCU. RESULTS: SCU at a sensitizing concentration promoted the 125 I-induced apoptosis and antiproliferative effect in A549 and H1975 cells. Moreover, the same results were obtained in vivo. Based on our findings, the AKT/mTOR pathway was significantly downregulated after combined treatment with 125 I and SCU. CONCLUSIONS: The results of our study suggested that SCU promotes the anticancer effects induced by 125 I in NSCLC cells by downregulating the AKT/mTOR pathway and lays a foundation for future application of this combined treatment.

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