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2D materials-based broadband photodetectors have extensive applications in security monitoring and remote sensing fields, especially in supersonic aircraft that require reliable performance under extreme high-temperature conditions. However, the integration of large-area heterostructures with 2D materials often involves high-temperature deposition methods, and also limited options and size of substrates. Herein, a liquid-phase spin-coating method is presented based on the interface engineering to prepare larger-area Van der Waals heterojunctions of black phosphorus (BP)/reduced graphene oxide (RGO) films at room temperature on arbitrary substrates of any required size. Importantly, this method avoids the common requirement of high-temperature, and prevents the curling or stacking in 2D materials during the liquid-phase film formation. The BP/RGO films-based devices exhibit a wide spectral photo-response, ranging from the visible of 532 nm to infrared range of 2200 nm. Additionally, due to Van der Waals interface of Schottky junction, the array devices provide infrared detection at temperatures up to 400 K, with an outstanding photoresponsivity (R) of 12 A W-1 and a specific detectivity (D*) of ≈2.4 × 109 Jones. This work offers an efficient approach to fabricate large-area 2D Schottky junction films by solution-coating for high-temperature infrared photodetectors.
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Bilayer semiconductors have attracted much attention due to their stacking-order-dependent properties. However, as both 3R- and 2H-stacking are energetically stable at high temperatures, most of the high-temperature grown bilayer materials have random 3R- or 2H-stacking orders, leading to non-uniformity in optical and electrical properties. Here, a chemical vapor deposition method is developed to grow bilayer semiconductors with controlled stacking order by modulating the resolidified chalcogen precursors supply kinetics. Taking tungsten disulfide (WS2 ) as an example, pure 3R-stacking (100%) and 2H-stacking dominated (87.6%) bilayer WS2 are grown by using this method and both show high structural and optical quality and good uniformity. Importantly, the bilayer 3R-stacking WS2 shows higher field effect mobility than 2H-stacking samples, due to the difference in stacking order-dependent surface potentials. This method is universal for growing other bilayer semiconductors with controlled stacking orders including molybdenum disulfide and tungsten diselenide, paving the way to exploit stacking-order-dependent properties of these family of emerging bilayer materials.
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High operating temperature (HOT) broadband photodetectors are urgently necessary for extreme condition applications in infrared-guided missiles, infrared night vision, fire safety imaging, and space exploration sensing. However, conventional photodetectors show dramatic carrier mobility decreases and carrier losses with low photoresponsivity at HOT due to the increased carrier scattering in channels at high temperatures. Herein, the HOT broadband photodetectors from room temperature to 470 K are developed for the first time by large-area black phosphorus (BP)/PtSe2 films device arrays via a depletion-enhanced photocarrier dynamics strategy. Attributed to the 2D Schottky junction at BP/PtSe2 interface and resulting in full depleted working channels, the BP/PtSe2 photodetector arrays exhibit high tolerance to carrier mobility decrease during the increasing operating temperature in a wide wavelength range from 532 to 2200 nm. Thus, the photodetector shows a state-of-the-art operating temperature at 470 K with the photo-responsivity (R) and specific detectivity (D*) of 25 A W-1 and 6.4 × 1011 Jones under 1850 nm illumination, respectively. Moreover, BP/PtSe2 photodetector arrays show high-uniformity photo-response in a large area. This work provides new strategies for high-performance broadband photodetector arrays with HOT by Schottky junction of large-area BP/PtSe2 films.
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The incorporation of heteroatoms and/or heptagons as the defects into helicenes expands the variety of chiroptical materials with novel properties. However, it is still challenging to construct novel boron-doped heptagon-containing helicenes with high photoluminescence quantum yields (PLQYs) and narrow full-width-at-half-maximum (FWHM) values. We report an efficient and scalable synthesis of a quadruple helicene 4Cz-NBN with two nitrogen-boron-nitrogen (NBN) units and a double helicene 4Cz-NBN-P1 bearing two NBN-doped heptagons, the latter could be formed via a two-fold Scholl reaction of the former. The helicenes 4Cz-NBN and 4Cz-NBN-P1 exhibit excellent PLQYs up to 99 % and 65 % with narrow FWHM of 24â nm and 22â nm, respectively. The emission wavelengths are tunable via stepwise titration experiments of 4Cz-NBN-P1 toward fluoride, enabling distinguished circularly polarized luminescence (CPL) from green, orange (4Cz-NBN-P1-F1) to yellow (trans/cis-4Cz-NBN-P1-F2) with near-unity PLQYs and broader circular dichroism (CD) ranges. The five structures of the aforementioned four helicenes were confirmed by single crystal X-ray diffraction analysis. This work provides a novel design strategy for construction of non-benzenoid multiple helicenes exhibiting narrow emissions with superior PLQYs.
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OBJECTIVES: In the present study, we aim to show the results of microwave ablation (MWA) for medically inoperable stage I non-small cell lung cancers (NSCLCs) with long-term follow-up. METHODS: From Feb 2011 to Mar 2016, patients with histologically proven clinical stage I NSCLC were treated with CT-guided MWA and retrospectively analyzed. The primary end point was overall survival (OS). Secondary end points included disease-free survival (DFS), cancer-specific survival (CSS), and complications. RESULTS: A total of 105 patients with 105 lesions underwent MWA. The mean age was 70.7 years (range: 40-86 years), and the mean diameter of all lesions was 2.40 cm (range: 0.9-4.0 cm). Adenocarcinoma was the most common histological type (77, 73.3%), followed by squamous cell carcinomas (21, 20%) and undefined NSCLC (7, 6.7%). With a median follow-up of 54.8 months, the median DFS was 36.0 months, and 1-, 3-, and 5-year DFS rates were 89.5%, 49.4%, and 42.7%, respectively. The median CSS and OS were 89.8 and 64.2 months, respectively. The OS rate was 99% at 1 year, 75.6% at 3 years, and 54.1% at 5 years, while the CSS rates were 99%, 78.9%, and 60.9%, respectively. Patients with stage IB lesions had significant shorter DFS (22.3 months vs. undefined, HR: 11.5, 95%CI: 5.85-22.40) and OS (37.3 vs. 89.8 months, HR: 8.64, 95% CI: 4.49-16.60) than IA disease. CONCLUSION: MWA is a safe, effective, and potentially curative therapy for medically inoperable stage I NSCLC patients. KEY POINTS: ⢠In this multicenter retrospective study which included 105 patients, we found the median overall survival (OS) was 64.2 months. The OS rate was 99% at 1 year, 75.6% at 3 years, and 54.1% at 5 years. ⢠Procedures were technically successful and well tolerated in all patients. Most MWA complications were mild or moderate.
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Técnicas de Ablación , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Microondas , Anciano , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Ablación por Catéter/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Microondas/uso terapéutico , Ablación por Radiofrecuencia , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Heterostructures for charge-carrier manipulation have laid the foundation of modern optoelectronic devices, such as photovoltaics and photodetectors. High-performance heterostructure devices usually impose stringent requirements on the material quality to sustain efficient carrier transport and charge transfer, thus leading to sophisticated fabrication processes. Here, a simple yet efficient strategy is proposed to develop ultrasensitive photodetectors based on heterostructures of chemical vapor deposition-grown MoS2 and polycrystalline-layered perovskites. The layered perovskites possess pure crystallographic orientation with conductive edges in contact with MoS2 , which gives rise to efficient light absorption, exciton diffusion, and interfacial charge transfer. In dark state, the mismatch of work functions of two materials facilitates low dark currents by the depletion of electrons in MoS2 . Under light irradiation, efficient exciton diffusion and interfacial charge transfer are realized in the heterostructures with type-II band alignment, which produces drifting electrons in MoS2 and leaves trapped holes in layered perovskites. The photodetectors present suppress noises and boost photocurrents, yielding a champion device with a responsivity of 2.5 × 104 A W-1 , and a specific detectivity of 4.1 × 1014 Jones. The results demonstrate a scalable approach for the integration of high-performance devices with high tolerance to defects.
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BACKGROUND: To explore the diagnostic value of radiomics features of preoperative computed tomography (CT) for triple negative breast cancer (TNBC) for better treatment of patients with breast cancer. METHODS: A total of 890 patients with breast cancer admitted to our hospital from June 2016 to January 2018 were analyzed. They were diagnosed by surgery and pathology to have mass and invasive breast cancer and had contrast-enhanced chest CT examination before operation. 300 patients were randomly selected for the study, including 100 TNBC and 200 non-TNBC (NTNBC) patients. Among them 180 were used in discovery group and 120 were used in validation group. The molecular subtypes of breast cancer in the patients were determined immunohistochemistrially. Radiomics features were extracted from three dimensional CT-images. The LASSO logistic method was used to select image features and calculate radiomics scores. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of radiomics scores for TNBC. RESULTS: Five image features were found to be related to TNBC subtype (P < 0.001). These image features based-radiomic signatures had good predictive values for TNBC with the areas under ROC curve (AUC) of 0.881 (95% CI: 0.781-0.921) in the discovery group and 0.851 (95% CI: 0.761-0.961) in the validation group, respectively. The sensitivities and specificities were 0.767, and 0.873 in the discovery group and 0.785 and 0.915 in the validation group. CONCLUSIONS: Radiomic signature based on preoperative CT is capable of distinguishing patients with TNBC and NTNBC. It adds additional value for conventional chest contrast-enhanced CT and helps plan the strategy for clinical treatment of the patients.
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Radiografía Torácica , Tomografía Computarizada por Rayos X/métodos , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Adulto , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Medios de Contraste , Femenino , Humanos , Persona de Mediana Edad , Intensificación de Imagen Radiográfica , Estudios RetrospectivosRESUMEN
OBJECTIVES: This prospective trial was performed to verify whether microwave ablation (MWA) in combination with chemotherapy could provide superior survival benefit compared with chemotherapy alone. MATERIALS AND METHODS: From March 1, 2015, to June 20, 2017, treatment-naïve patients with pathologically verified advanced or recurrent non-small cell lung cancer (NSCLC) were randomly assigned to MWA plus chemotherapy group or chemotherapy group. The primary endpoint was progression-free survival (PFS), while the secondary endpoints included overall survival (OS), time to local progression (TTLP), and objective response rate (ORR). The complications and adverse events were also reported. RESULTS: A total of 293 patients were randomly assigned into the two groups. One hundred forty-eight patients with 117 stage IV tumors were included in the MWA plus chemotherapy group. One hundred forty-five patients with 113 stage IV tumors were included in the chemotherapy group. The median follow-up period was 13.1 months and 12.4 months, respectively. Median PFS was 10.3 months (95% CI 8.0-13.0) in the MWA plus chemotherapy group and 4.9 months (95% CI 4.2-5.7) in the chemotherapy group (HR = 0.44, 95% CI 0.28-0.53; p < 0.0001). Median OS was not reached in the MWA plus chemotherapy group and 12.6 months (95% CI 10.6-14.6) in the chemotherapy group (HR = 0.38, 95% CI 0.27-0.53; p < 0.0001) using Kaplan-Meier analyses with log-rank test. The median TTLP was 24.5 months, and the ORR was 32% in both groups. The adverse event rate was not significantly different in the two groups. CONCLUSIONS: In patients with advanced NSCLC, longer PFS and OS can be achieved with the treatment of combined MWA and chemotherapy than chemotherapy alone. KEY POINTS: ⢠Patients treated with MWA plus chemotherapy had superior PFS and OS over those treated with chemotherapy alone. ⢠The ORR of patients treated with MWA plus chemotherapy was similar to that of those treated with chemotherapy alone. ⢠Complications associated with MWA were common but tolerable and manageable.
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Adenocarcinoma del Pulmón/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , Microondas/uso terapéutico , Recurrencia Local de Neoplasia/terapia , Ablación por Radiofrecuencia/métodos , Adenocarcinoma del Pulmón/patología , Adulto , Anciano , Anciano de 80 o más Años , Carboplatino/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/patología , Cisplatino/administración & dosificación , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Docetaxel/administración & dosificación , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Compuestos Organoplatinos/administración & dosificación , Paclitaxel/administración & dosificación , Pemetrexed/administración & dosificación , Supervivencia sin Progresión , Estudios Prospectivos , Resultado del Tratamiento , Vinorelbina/administración & dosificación , GemcitabinaRESUMEN
Harmful blooms of Prorocentrum donghaiense occur annually in the phosphorus-scarce coastal waters of the East China Sea (ECS). The enzymatic activities of alkaline phosphatase (AP) and its regulation by external phosphorus were studied during a P. donghaiense bloom in this area. The AP characteristics of P. donghaiense was further compared with Prorocentrum minimum and Prorocentrum micans in monocultures with both bulk and single-cell enzyme-labeled fluorescence AP assays. Concentrations of dissolved inorganic phosphorus (DIP) varied between 0.04 and 0.73 µmol l-1, with more than half recording stations registering concentrations below 0.10 µmol l-1. Concentrations of dissolved organic phosphorus (DOP) were comparable or even higher than those of DIP. P. donghaiense suffered phosphorus stress and expressed abundant AP, especially when DIP was lower than 0.10 µmol l-1. The AP activities showed a negative correlation with DIP but a positive correlation with DOP. The AP activities were also regulated by internal phosphorus pool. The sharp increase in AP activities was observed until cellular phosphorus was exhausted. Most AP of P. donghaiense was located on the cell surface and some were released into the water with time. Compared with P. minimum and P. micans, P. donghaiense showed a higher AP affinity for organic phosphorus substrates, a more efficient and energy-saving AP expression quantity as a response to phosphorus deficiency. The unique AP characteristic of P. donghaiense suggests that it benefits from the efficient utilization of DOP, and outcompete other species in the phosphorus-scarce ECS.
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Fosfatasa Alcalina/metabolismo , Dinoflagelados/enzimología , Floraciones de Algas Nocivas , Fósforo/deficiencia , Fitoplancton/enzimología , China , Especificidad de la EspecieRESUMEN
Low-dimensional semiconductors have attracted considerable attention due to their unique structures and remarkable properties, which makes them promising materials for a wide range of applications related to electronics and optoelectronics. Herein, the preparation of 1D Sb2 Se3 nanowires (NWs) with high crystal quality via chemical vapor deposition growth is reported. The obtained Sb2 Se3 NWs have triangular prism morphology with aspect ratio range from 2 to 200, and three primary lattice orientations can be achieved on the sixfold symmetry mica substrate. Angle-resolved polarized Raman spectroscopy measurement reveals strong anisotropic properties of the Sb2 Se3 NWs, which is also developed to identify its crystal orientation. Furthermore, photodetectors based on Sb2 Se3 NW exhibit a wide spectral photoresponse range from visible to NIR (400-900 nm). Owing to the high crystallinity of Sb2 Se3 NW, the photodetector acquires a photocurrent on/off ratio of about 405, a responsivity of 5100 mA W-1 , and fast rise and fall times of about 32 and 5 ms, respectively. Additionally, owing to the anisotropic structure of Sb2 Se3 NW, the device exhibits polarization-dependent photoresponse. The high crystallinity and superior anisotropy of Sb2 Se3 NW, combined with controllable preparation endows it with great potential for constructing multifunctional optoelectronic devices.
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Semimetal 1T' MoTe2 crystals have attracted tremendous attention owing to their anisotropic optical properties, Weyl semimetal, phase transition, and so on. However, the complex refractive indices (n-ik) of the anisotropic semimetal 1T' MoTe2 still are not revealed yet, which is important to applications such as polarized wide spectrum detectors, polarized surface plasmonics, and nonlinear optics. Here, the linear dichroism of as-grown trilayer 1T' MoTe2 single crystals is investigated. Trilayer 1T' MoTe2 shows obvious anisotropic optical absorption due to the intraband transition of dz 2 orbits for Mo atoms and px orbits for Te atoms. The anisotropic complex refractive indices of few-layer 1T' MoTe2 are experimentally obtained for the first time by using the Pinier equation analysis. Based on the linear dichroism of 1T' MoTe2 , angle-resolved polarized optical microscopy is developed to visualize the grain boundary and identify the crystal orientation of 1T' MoTe2 crystals, which is also an excellent tool toward the investigation of the optical absorption properties in the visible range for anisotropic 2D transition metal chalcogenides. This work provides a universal and nondestructive method to identify the crystal orientation of anisotropic 2D materials, which opens up an opportunity to investigate the optical application of anisotropic semimetal 2D materials.
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Using the MoS2 -WTe2 heterostructure as a model system combined with electrochemical microreactors and density function theory calculations, it is shown that heterostructured contacts enhance the hydrogen evolution reaction (HER) activity of monolayer MoS2 . Two possible mechanisms are suggested to explain this enhancement: efficient charge injection through large-area heterojunctions between MoS2 and WTe2 and effective screening of mirror charges due to the semimetallic nature of WTe2 . The dielectric screening effect is proven minor, probed by measuring the HER activity of monolayer MoS2 on various support substrates with dielectric constants ranging from 4 to 300. Thus, the enhanced HER is attributed to the increased charge injection into MoS2 through large-area heterojunctions. Based on this understanding, a MoS2 /WTe2 hybrid catalyst is fabricated with an HER overpotential of -140 mV at 10 mA cm-2 , a Tafel slope of 40 mV dec-1 , and long stability. These results demonstrate the importance of interfacial design in transition metal dichalcogenide HER catalysts. The microreactor platform presents an unambiguous approach to probe interfacial effects in various electrocatalytic reactions.
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Monolayer WSe2 exhibits unique optical and electronic properties, showing great potential applications in functional integrated devices, such as electronic devices and optoelectronics. Understanding the growth behavior and process are the key points for the salt-assisted growth of large domain WSe2 monolayers, it is also very important for its further application in on-chip laser and opto-devices. Here, we report a NaCl-assistant method for controlled growth of single crystal monolayer WSe2 with a domain size up to 0.57 mm on SiO2/Si substrate. Atomic-resolution scanning transmission electron microscopy reveals that the Se1 and Se2 vacancy point defects are the main defect type of those materials. The growth behavior of the salt-assisted method have been systemly investigated. The loading mass of NaCl powder prefers to be less with the controllable vapor process. The flow of hydrogen gas was also preferred to be suitable with a weak etching effect. The morphology of monolayer WSe2 shows a sensitive temperature dependence evolution with the growth temperature increasing. A screw dislocation growth behavior with 15° angle is also observed with the NaCl-assistant method. The results provide a deep understanding of the mechanism for the NaCl-assistant growth of large size monolayer WSe2.
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Objective: This study evaluated the effect of oxytocin administration prior to microwave ablation (MWA) of hypervascular uterine fibroids. Methods: Thirty-two patients with 38 hypervascular uterine fibroids (Adler blood flow grade 3) were equally apportioned to receive intravenous oxytocin infusion (0.32 U/min) 20 min before ultrasound-guided percutaneous MWA, or no oxytocin (control). Changes in Adler blood supply grade and myoma volume were observed via color Doppler ultrasonography (CDU). All patients underwent quantitative ablation with single or double needle and microwave power 50 W (180 s). Treatment continued for those who did not reach the therapeutic goal. The myoma necrotic volume was evaluated by contrast-enhanced ultrasound. Ablation rate was the percent of MRI nonenhanced myoma volume after treatment, relative to myoma volume before treatment, 2 days after surgery. Results: Twenty minutes after oxytocin administration, CDU showed significant decrease of blood vessels in myomas, and Adler blood supply decreased from grade 3 to grade 1 or grade 0 in 10 and 9 myomas, respectively. Myoma volumes were reduced by 2.12 ± 0.24%. Necrotic volumes in the oxytocin (control) groups were 36.96 ± 2.78 cm3 (22.68 ± 3.38 cm3) and ablation rates were 95.4 ± 2.7% (85.7 ± 3.3%; t = 12.68, 8.866, p = 0.001, both). No serious complication was noted. Conclusion: Intravenous oxytocin administered before percutaneous MWA of hypervascular uterine fibroids can effectively block the blood supply vessels of the myoma, reduce the heat sink effect, and thereby increase the ablation volume and improve the local therapeutic effect.
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Ultrasonido Enfocado de Alta Intensidad de Ablación , Leiomioma/tratamiento farmacológico , Leiomioma/cirugía , Microondas/uso terapéutico , Oxitócicos/uso terapéutico , Oxitocina/uso terapéutico , Neoplasias Uterinas/tratamiento farmacológico , Neoplasias Uterinas/cirugía , Adulto , Femenino , Humanos , Resultado del Tratamiento , Ultrasonografía Doppler en ColorRESUMEN
Graphdiyne (GDY), a novel large π-conjugated carbon material, for the first time, is introduced as the hole transfer layer into a photoelectrochemical water splitting cell (PEC). Raman and ultraviolet photoelectron spectroscopic studies indicate the existence of relatively strong π-π interactions between GDY and 4-mercaptopyridine surface-functionalized CdSe quantum dots, beneficial to the hole transportation and enhancement of the photocurrent performance. Upon exposure to a Xe lamp, the integrated photocathode produces a current density of nearly -70 µA cm(-2) at a potential of 0 V vs NHE in neutral aqueous solution. Simultaneously, the photocathode evolves H2 with 90 ± 5% faradic efficiency over three times and exhibits good stability within 12 h. All of the results indicate that GDY is a promising hole transfer material to fabricate a PEC device for water splitting by solar energy.
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2D transition metal dichalcogenide (TMD) alloys with tunable band gaps have recently gained wide interest due to their potential applications in future nanoelectronics and optoelectronics. Here, we report the temperature-dependent photoluminescence (PL) and Raman spectra of Mo1-x W x S2 monolayers with W composition x = 0, 0.29, 0.53, 0.66 and 1 in the temperature range 93-493 K. We observed a linear temperature dependence of PL emission energy and Raman frequency. The PL intensity is enhanced at high temperature (>393 K). The temperature coefficients are negative for both PL and Raman bands, which may result from anharmonicity, thermal expansion and composition disorder.
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Group IVB transition metal (Zr and Hf) dichalcogenide (TMD) monolayers can have higher carrier mobility and higher tunneling current density than group VIB (Mo and W) TMD monolayers. Here we report the synthesis of hexagonal ZrS2 monolayer and few layers on hexagonal boron nitride (BN) using ZrCl4 and S as precursors. The domain size of ZrS2 hexagons is around 1-3 µm. The number of layers of ZrS2 was controlled by tuning the evaporation temperature of ZrCl4. The stacking angle between ZrS2 and BN characterized by transmission electron microscopy shows a preferred stacking angle of near 0°. Field-effect transistors (FETs) fabricated on ZrS2 flakes showed n-type transport behavior with an estimated mobility of 0.1-1.1 cm(2) V(-1) s(-1).
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A 2D atomic-layer-thickness phototransistor based on a graphene-MoS2 bybrid device is constructed with a photoresponse much larger than that of individual graphene or MoS2 based phototransistors. Strong and selective light absorption in the MoS2 layer creates electric charges that are transferred to graphene layers derived by a build-in electrical field, where they recirculate many times due to the high carrier mobility of graphene. Gate tunable Fermi level in graphene layer allows the responsivity of this hybrid phototransistor to be continuously tuned from 0 to about 10(4) mA/W by the gate voltage. Furthermore, large scale, flexible, and transparent 2D phototransistors with high responsivity are constructed from the CVD-grown graphene and MoS2 flakes. The high responsivity, gate-tunable sensitivity, wavelength selectivity, and compatibility with current circuit technologies of this type device give it great potential for future application in integrated nano-optoelectronic systems.
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DNA damage-regulated autophagy modulator protein 1 (DRAM1), a multi-pass membrane lysosomal protein, is reportedly a tumor protein p53 (TP53) target gene involved in autophagy. During cerebral ischemia/reperfusion (I/R) injury, DRAM1 protein expression is increased, and autophagy is activated. However, the functional significance of DRAM1 and the relationship between DRAM1 and autophagy in brain I/R remains uncertain. The aim of this study is to investigate whether DRAM1 mediates autophagy activation in cerebral I/R injury and to explore its possible effects and mechanisms. We adopt the oxygen-glucose deprivation and reperfusion (OGD/R) Neuro-2a cell model to mimic cerebral I/R conditions in vitro, and RNA interference is used to knock down DRAM1 expression in this model. Cell viability assay is performed using the LIVE/DEAD viability/cytotoxicity kit. Cell phenotypic changes are analyzed through Western blot assays. Autophagy flux is monitored through the tandem red fluorescent protein-Green fluorescent protein-microtubule associated protein 1 light chain 3 (RFP-GFP-LC3) construct. The expression levels of DRAM1 and microtubule associated protein 1 light chain 3II/I (LC3II/I) are strongly up-regulated in Neuro-2a cells after OGD/R treatment and peaked at the 12 h reperfusion time point. The autophagy-specific inhibitor 3-Methyladenine (3-MA) inhibits the expression of DRAM1 and LC3II/I and exacerbates OGD/R-induced cell injury. Furthermore, DRAM1 knockdown aggravates OGD/R-induced cell injury and significantly blocks autophagy through decreasing autophagosome-lysosome fusion. In conclusion, our data demonstrate that DRAM1 knockdown in Neuro-2a cells inhibits autophagy by blocking autophagosome-lysosome fusion and exacerbated OGD/R-induced cell injury. Thus, DRAM1 might constitute a new therapeutic target for I/R diseases.
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Autofagia/fisiología , Isquemia Encefálica/metabolismo , Glucosa/metabolismo , Proteínas de la Membrana/metabolismo , Neuroblastoma/metabolismo , Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Adenina/análogos & derivados , Adenina/farmacología , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Free-standing covalent organic framework (COFs) nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li+ in lithium-ion batteries, while simultaneously exposing affluent active sites in supercapacitors. The development of these nanofilms offers a promising solution to address the persistent challenge of imbalanced charge storage kinetics between battery-type anode and capacitor-type cathode in lithium-ion capacitors (LICs). Herein, for the first time, custom-made COFBTMB-TP and COFTAPB-BPY nanofilms are synthesized as the anode and cathode, respectively, for an all-COF nanofilm-structured LIC. The COFBTMB-TP nanofilm with strong electronegative-CF3 groups enables tuning the partial electron cloud density for Li+ migration to ensure the rapid anode kinetic process. The thickness-regulated cathodic COFTAPB-BPY nanofilm can fit the anodic COF nanofilm in the capacity. Due to the aligned 1D channel, 2D aromatic skeleton and accessible active sites of COF nanofilms, the whole COFTAPB-BPY//COFBTMB-TP LIC demonstrates a high energy density of 318 mWh cm-3 at a high-power density of 6 W cm-3, excellent rate capability, good cycle stability with the capacity retention rate of 77% after 5000-cycle. The COFTAPB-BPY//COFBTMB-TP LIC represents a new benchmark for currently reported film-type LICs and even film-type supercapacitors. After being comprehensively explored via ex situ XPS, 7Li solid-state NMR analyses, and DFT calculation, it is found that the COFBTMB-TP nanofilm facilitates the reversible conversion of semi-ionic to ionic C-F bonds during lithium storage. COFBTMB-TP exhibits a strong interaction with Li+ due to the C-F, C=O, and C-N bonds, facilitating Li+ desolation and absorption from the electrolyte. This work addresses the challenge of imbalanced charge storage kinetics and capacity between the anode and cathode and also pave the way for future miniaturized and wearable LIC devices.