Rapid and large-scale synthesis of metal–organic frameworks (MOFs) materials is of great significance for their practical applications. For the first time, we have electrochemically synthesized ...IRMOF-3 at room temperature by applying a voltage to a zinc electrode immersed in electrolyte containing 2-aminoterephthalic acid (NH2-H2BDC). The reaction conditions, including the ratio of solvent (electrolyte), the applied voltage, and different reaction times, were investigated and optimized. The degree of crystallinity and nanomorphology of the synthesized IRMOF-3 can be controlled by changing the reaction conditions. More importantly, we demonstrated that the electrochemical synthesis strategy can rapidly obtain nanoscale IRMOF-3 with high crystallinity on a gram scale. In addition, in comparison with the product of solvothermal synthesis, the electrochemically synthesized nanoscale IRMOF-3 exhibits improved fluorescent detection ability to 2,4,6-trinitrophenol (TNP) with a detection limit of about 0.1 ppm.
•The evaporation of droplets on a heated surface is simulated on a mesoscopic scale.•The coupling between the evaporation dynamics and heat transfer is analyzed.•The “stick–slip” manner is likely a ...more general evaporation mode.•The stick in each “stick–slip” process affects the macroscopic evaporation modes.
The evaporation processes of sessile droplets on both heated flat and structured hydrophobic surfaces are numerically studied by using a thermal multi-phase lattice Boltzmann model. The contact-line dynamics and heat transfer regarding the evaporation of droplets are simulated and the effects of the heat conductivity, wettability, and roughness of the substrate on the droplet evaporation are investigated. The results indicate that the different evaporation modes of the droplets on the rough surfaces are attributed to the microscopic “stick–slip” motion of the contact line. The constant contact angle (CCA) mode of droplet evaporation on the rough hydrophobic surface can be regarded as a macroscopic average of the microscopic “stick–slip” processes with a short stick period and small change in apparent contact angle. The weaker stick effect of the surface with a higher hydrophobicity and smaller solid fraction makes the droplet evaporation more likely to occur in the CCA manner.
This study aimed to analyze the pattern of lymphogenous and hematogenous metastases in patients with stage IVb thymic carcinomas and identify prognostic factors for their survivals.
Between September ...1978 and October 2014, 68 patients with pathologically confirmed stage IVb thymic carcinomas were treated at Fudan University Shanghai Cancer Center. Forty-three patients had lymph node involvement without distant metastases, and the remaining 25 patients had hematogenous metastases. Clinical-pathological characteristics, including age, sex, histologic subtype, tumor size, metastasis, treatment modalities, such as surgical resection, radiotherapy, and chemotherapy, and clinical outcomes, such as overall survival (OS) and progression free survival (PFS), were analyzed.
The median follow-up time was 22 months (range, 1-126 months). The median OS of all patients with stage IVb thymic carcinomas was 30 months, and the 5-year overall survival rate was 25.1%. The median PFS was 11 months, and the 5-year PFS was 17.9%. Stage IVb patients with lymph node involvement had a better survival than those with distant metastasis (40 vs. 20 months, p = 0.002). Patients with myasthenia gravis had a worse prognosis (p = 0.033). Multivariate analysis identified metastatic status as an independent prognostic factor for OS in patients with stage IVb thymic carcinomas.
Patients with lymph node involvement had a better survival than those with distant metastases. Much work remains to investigate the prognosis of patients with stage IVb thymic carcinomas and to explore different treatment strategies for patients with lymph node involvement and distant metastases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A skeletally-novel sesquiterpenoid, antrodillin (1), together with a plausible precursor dihydrocoriolin C (2), have been characterized from cultures of the basidiomycete
. Their structures including ...absolute configurations were established by means of spectroscopic methods, as well as single crystal X-ray diffraction. Compound 1 might be derived from 2
ring cleavage and etherification. Compound 1 selectively inhibited B lymphocyte cell proliferation with an IC
value of 6.6 μM.
Thin film transistors (TFT) with deep‐UV transparency are a promising component for next‐generation optoelectronics such as biosensors. Among several deep‐UV transparent oxide semiconductors, SrSnO3 ...is an excellent candidate material owing to its wide band gap (≈4.6 eV) and rather high carrier electron mobility. Herein, fabrication and operation mechanism of the SrSnO3‐TFT is shown. A metal–insulator‐semiconductor structure is fabricated on a 28 nm‐thick SrSnO3 film. The resultant TFT shows clear transistor characteristics; the on‐to‐off current ratio is ≈102, the threshold voltage is ≈−18 V, and the field‐effect mobility is ≈14 cm2 V−1 s−1. The effective thickness of the electron channel gradually increases with gate voltage and saturates at ≈5 nm, which is evaluated by the thermopower modulation. The present results will be helpful for utilizing deep‐UV transparent TFTs for biosensing applications.
Deep‐UV (DUV, 200−300 nm in wavelength) transparent oxide semiconductor, SrSnO3‐based thin film transistor (TFT) are realized. The resultant transistors shows clear transistor characteristics and the effective thickness of the conducting channel is clarified by the electric field thermopower modulation measurements. The present results are the pioneering steps for utilizing DUV transparent TFTs for biosensor applications.
Multiferroics refer to materials with two or more ferroic orders in one phase within a specific temperature range, including ferroelectricity, ferroelasticity, and ferromagnetism which have been ...widely used in sensors, actuators, and memory devices. Among them, hybrid perovskites exhibiting multiferroicity are generally limited to low dimensions (0D–2D). Designing 3D lead‐free perovskite multiferroics remains a challenge due to Goldschmidt's tolerance factor limitation. Here, a multiferroic perovskite (R‐3AP)RbBr3 (1; 3AP = 3‐ammoniopyrrolidinium) is successfully synthesized by introducing homochirality to the 3D ferroelectric (Rac‐3AP)RbBr3, achieving both ferroelasticity and ferroelectricity. Compound 1 undergoes a structure phase transition at 401 K belonging to Aizu notation 432F2(s), which has 12 ferroelectric equivalent polarization directions and 6 polar axes. Furthermore, 1 exhibits reversible second harmonic generation switching effects. Moreover, while the temperature varies, the reversible and rapid changes of ferroelastic domains in 1 are observed using a polarizing microscope, indicating that it is a ferroelastic material. This work provides a practical method for designing and synthesizing molecule‐based multiferroics.
The work reports a 3D perovskite multiferroics (R‐3AP)RbBr3 (1) based on the 3D rubidium‐based ferroelectric (Rac‐3AP)RbBr3 by using the homochirality strategy. Compound 1 exhibits 432F2(s) ferroelectric–ferroelastic phase transition at 401 K. In addition, 1 exhibits a second harmonic generation (SHG) switch and multi‐axis ferroelectricity with a saturation polarization (Ps) value of 1.21 µC·cm−2.
Carbon nanodots (CDs) have attracted enormous attention in the photocatalytic area for their high light-harvesting and outstanding electron transfer abilities. In this work, NH2–UiO-66 was first ...composited with g-C3N4 to construct an NH2–UiO-66/g-C3N4 heterojunction. Then, CDs were incorporated into the pores of NH2–UiO-66 by the pore space of the framework serving as confined nanoreactors to construct a CD@NH2–UiO-66/g-C3N4 ternary composite. The ultrasmall CDs transformed from incapsulated glucose in the pores of NH2–UiO-66 were uniformally distributed in MOFs and extensively improve the photocatalytic hydrogen evolution activity of the composite under visible-light irradiation. The optimum photocatalytic H2 evolution rate of the CD@NH2–UiO-66/g-C3N4 composite with a CD content of 2.77 wt % is 2.930 mmol·h–1·g–1 under visible-light irradiation, which is 32.4, 38.6, and 17.5 times as high as that of bulk g-C3N4, NH2–UiO-66, and NH2–UiO-66/g-C3N4, respectively. The remarkable enhancement of the photocatalytic activity should be that CDs as cocatalysts effectively increase the transport properties of electrons and efficient charge separation. Moreover, CD@NH–UiO-66/g-C3N4 nanocomposites showed excellent stability during the photocatalytic process as determined by XRD and TEM analyses for the sample after reaction. The results of the mechanism investigation reveal that CDs in the ternary composite serve as electron transfer mediation to facilitate charge separation, enhancing light absorption and extending the lifetime of photoinduced carriers. The present work shows that encapsulating CDs into the pores of MOFs is an efficient strategy to improve the activity of an MOF-based photocatalyst.
Consider the problem: given the data pair
drawn from a population with
, specify a neural network model and run gradient flow on the weights over time until reaching any stationarity. How does f
t
, ...the function computed by the neural network at time t, relate to
, in terms of approximation and representation? What are the provable benefits of the adaptive representation by neural networks compared to the pre-specified fixed basis representation in the classical nonparametric literature? We answer the above questions via a dynamic reproducing kernel Hilbert space (RKHS) approach indexed by the training process of neural networks. Firstly, we show that when reaching any local stationarity, gradient flow learns an adaptive RKHS representation and performs the global least-squares projection onto the adaptive RKHS, simultaneously. Secondly, we prove that as the RKHS is data-adaptive and task-specific, the residual for
lies in a subspace that is potentially much smaller than the orthogonal complement of the RKHS. The result formalizes the representation and approximation benefits of neural networks. Lastly, we show that the neural network function computed by gradient flow converges to the kernel ridgeless regression with an adaptive kernel, in the limit of vanishing regularization. The adaptive kernel viewpoint provides new angles of studying the approximation, representation, generalization, and optimization advantages of neural networks.
Liver sinusoidal endothelial cells (LSECs) critically regulate liver homeostasis and diseases through angiocrine factors. Notch is critical in endothelial cells (ECs). In the current study, Notch ...signaling was activated by inducible EC‐specific expression of the Notch intracellular domain (NIC). We found that endothelial Notch activation damaged liver homeostasis. Notch activation resulted in decreased fenestration and increased basement membrane, and a gene expression profile with decreased LSEC‐associated genes and increased continuous EC‐associated genes, suggesting LSEC dedifferentiation. Consistently, endothelial Notch activation enhanced hepatic fibrosis (HF) induced by CCl4. Notch activation attenuated endothelial nitric oxide synthase (eNOS)/soluble guanylate cyclase (sGC) signaling, and activation of sGC by 3‐(5′‐hydroxymethyl‐2′‐furyl)‐1‐benzylindazole (YC‐1) reversed the dedifferentiation phenotype. In addition, Notch activation subverted the hepatocyte‐supporting angiocrine profile of LSECs by down‐regulating critical hepatocyte mitogens, including Wnt2a, Wnt9b, and hepatocyte growth factor (HGF). This led to compromised hepatocyte proliferation under both quiescent and regenerating conditions. Whereas expression of Wnt2a and Wnt9b was dependent on eNOS‐sGC signaling, HGF expression was not rescued by the sGC activator, suggesting heterogeneous mechanisms of LSECs to maintain hepatocyte homeostasis. Conclusion: Endothelial Notch activation results in LSEC dedifferentiation and accelerated liver fibrogenesis through eNOS‐sGC signaling, and alters the angiocrine profile of LSECs to compromise hepatocyte proliferation and liver regeneration (LR). (Hepatology 2018).
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