This paper is concerned with the robust stabilization of quantized feedback sliding-mode control (SMC) for a class of uncertain linear systems via an event-triggered approach. By introducing an ...event-triggered mechanism, the event-triggered state instead of the state itself is quantized. And the generated finite event-triggered quantized state signal is sent through a digital network to the decoder and used for constructing a sliding mode controller to stabilize the uncertain linear systems. The relation among the lower bound of the quantized measurement saturating parameter, the upper bound of the event-triggered threshold parameter and the robust stabilization condition of linear uncertain systems, is first presented. Then, under the relation and by the combination of the proposed event-triggered mechanism for the system state and the discrete on-line adjustment policy for the quantizer sensitivity, the established quantized and event-triggered SMC laws are shown to ensure the reachability of the desired switching surface and global robust stabilization of uncertain linear systems is achieved. The theoretical result is verified via simulation illustration finally.
Rational design and synthesis of hollow core-shell hetero-structures with high complexity still remains challenging for high-performance supercapacitors. Here, a simple and effective strategy that ...involves a 'root-etch-wrap' process was developed to synthesize hollow core-shell hetero-structured electrodes. Specifically, ZnO hollow spheres take root on carbon cloth
via
an
in situ
growth routine, then are etched to aid the generation of a ZIF-8 shell. As-synthesized hollow core-shell ZnO@ZIF-8 is wrapped by PANI nanocoating, resulting in a flexible conductive porous electrode (denoted as PANI/ZnO@ZIF-8-CC). The optimized electrode exhibits an ultrahigh areal capacitance (4839-3987 mF cm
−2
at 5-30 mA cm
−2
), which is at least 3 times higher than that of PANI-CC and ZnO@ZIF-8-CC owing to the synergistic effect. In addition, a symmetric flexible supercapacitor fabricated by PANI/ZnO@ZIF-8-CC exhibits a high energy density of 0.137-0.0891 mW h cm
−3
(at a power density of 1.421-23.629 W cm
−3
) and a good long-term cycling ability (87% for 10 000 cycles at 5 mA cm
−2
). All of these results make unique core-shell structured PANI/ZnO@ZIF-8-CC a promising electrode material for advanced energy storage and conversion applications.
A hollow core-shell hetero-structured electrode (PANI/ZnO@ZIF-8-CC) is designed and synthesized
via
a 'root-etch-wrap' process for flexible supercapacitors. The unique structure,
in situ
growth strategy and synergistic effects endow PANI/ZnO@ZIF-8-CC with ultrahigh areal capacitance and good cycling stability.
•Syn, CgA and CD56 were related to the prognosis of LCNEC.•Adenocarcinoma was the most common combined components for LCNEC.•SCLC chemotherapy regimen is a more effective choice for LCNEC.•Overall ...survival of combined LCNEC tended to be shorter than pure LCNEC.
The 2015 World Health Organization classification defines pulmonary large-cell neuroendocrine carcinoma (LCNEC) as a high-grade neuroendocrine carcinoma. However, the clinical characteristics and prognostic factors of pure LCNEC and combined LCNEC remain unclear. Hence, we performed a multi-center retrospective study to compare the clinical outcomes of pure versus combined LCNEC.
Data from 381 patients with pulmonary LCNEC admitted to 17 Chinese institutes between 2009 and 2016 were collected retrospectively. Clinical characteristics and prognosis were analyzed among patients receiving adjuvant (adjuvant group; n = 56) and first-line (first-line group; n = 146) chemotherapy, as well as among patients receiving small cell lung cancer (SCLC) and non-SCLC (NSCLC) chemotherapy regimens. The Kaplan-Meier method and multivariable Cox regression were used to identify clinicopathological variables that might influence patient outcomes.
Expression levels of neuroendocrine markers (synaptophysin, chromogranin-A, CD56) were associated with patients’ prognosis in the total study cohort. In the adjuvant group, median disease-free survival was non-significantly longer for SCLC-based regimens than for NSCLC-based regimens (P = 0.112). In the first-line group, median progression-free survival was significantly longer for SCLC-based regimens than for NSCLC-based regimens (11.5 vs. 7.2 months, P = 0.003). Among patients with combined LCNEC, adenocarcinoma was the most common combined component, accounting for 70.0 % of cases. Additionally, median overall survival was non-significantly shorter for combined LCNEC than for pure LCNEC (P = 0.083).
The SCLC regimen is a more effective choice, as either first-line or adjuvant chemotherapy, when compared to the NSCLC regimen for LCNEC treatment. Further studies are needed to clarify the survival differences between patients with pure-, and combined LCNEC.
Competing inhomogeneous orders are a central feature of correlated electron materials, including the high-temperature superconductors. The two-dimensional Hubbard model serves as the canonical ...microscopic physical model for such systems. Multiple orders have been proposed in the underdoped part of the phase diagram, which corresponds to a regime of maximum numerical difficulty. By combining the latest numerical methods in exhaustive simulations, we uncover the ordering in the underdoped ground state. We find a stripe order that has a highly compressible wavelength on an energy scale of a few kelvin, with wavelength fluctuations coupled to pairing order. The favored filled stripe order is different from that seen in real materials. Our results demonstrate the power of modern numerical methods to solve microscopic models, even in challenging settings.
Conspectus Supramolecular polymers, fabricated via the combination of supramolecular chemistry and polymer science, are polymeric arrays of repeating units held together by reversible, relatively ...weak noncovalent interactions. The introduction of noncovalent interactions, such as hydrogen bonding, aromatic stacking interactions, metal coordination, and host–guest interactions, endows supramolecular polymers with unique stimuli responsiveness and self-adjusting abilities. As a result, diverse monomer structures have been designed and synthesized to construct various types of supramolecular polymers. By changing the noncovalent interaction types, numbers, or chemical structures of functional groups in these monomers, supramolecular polymeric materials can be prepared with tailored chemical and physical properties. In recent years, the interest in supramolecular polymers has been extended from the preparation of intriguing topological structures to the discoveries of potential applications as functional materials. Compared with traditional polymers, supramolecular polymers show some advantages in the fabrication of reversible or responsive materials. The development of supramolecular polymers also offers a platform to construct complex and sophisticated materials with a bottom-up approach. Macrocylic hosts, including crown ethers, cyclodextrins, calixarenes, cucurbiturils, and pillararenes, are the most commonly used building blocks in the fabrication of host–guest interaction-based supramolecular polymers. With the introduction of complementary guest molecules, macrocylic hosts demonstrate selective and stimuli-responsive host–guest complexation behaviors. By elaborate molecular design, the resultant supramolecular polymers can exhibit diverse structures based on the self-selectivity of host–guest interactions. The introduction of reversible host–guest interactions can further endow these supramolecular polymers with interesting and fascinating chemical/physical properties, including stimuli responsiveness, self-healing, and environmental adaptation. It has been reported that macrocycle-based supramolecular polymers can respond to pH change, photoirradition, anions, cations, temperature, and solvent. Macrocycle-based supramolecular polymers have been prepared in solution, in gel, and in the solid state. Furthermore, the solvent has a very important influence on the formation of these supramolecular polymers. Crown ether- and pillararene-based supramolecular polymers have mainly formed in organic solvents, such as chloroform, acetone, and acetonitrile, while cyclodextrin- and cucurbituril-based supramolecular polymerizations have been usually observed in aqueous solutions. For calixarenes, both organic solvents and water have been used as suitable media for supramolecular polymerization. With the development of supramolecular chemistry and polymer science, various methods, such as nuclear magnetic resonance spectroscopy, X-ray techniques, electron microscopies, and theoretical calculation and computer simulation, have been applied for characterizing supramolecular polymers. The fabrication of macrocycle-based supramolecular polymers has become a currently hot research topic. In this Account, we summarize recent results in the investigation of supramolecular polymers constructed from macrocycle-based host–guest molecular recognition motifs. These supramolecular polymers are classified based on the different macrocycles used in them. Their monomer design, structure control, stimuli-responsiveness, and applications in various areas are discussed, and future research directions are proposed. It is expected that the development of supramolecular polymers will not only change the way we live and work but also exert significant influence on scientific research.
The last decade has witnessed an extensive uptake of clean and sustainable energy sources to meet the surging energy demand while mitigating the increasing levels of greenhouse gas emission and air ...pollution. Among various energy systems, electrochemical energy storage devices such as batteries and supercapacitors have attracted worldwide attention for use in electric-powered transport, portable electronics, and biomedical devices. Recently, new multifunctional supercapacitors, which combine energy storage capability with load-carrying and other functions, offer a new "two-birds-one-stone" strategy for next-generation energy storage systems to store energy beyond the traditional systems. Multifunctional supercapacitors show great promise in reducing the size and volume of devices, improving the charge storage capacity, and minimising the cost in materials and fabrication while bringing the benefits of additional functions to the systems. This review describes the recent advances in multifunctional supercapacitors in terms of materials design, device configuration, system integration, and applications. The unique features of multifunctional supercapacitors depend strongly on architectural designs and system integration, which allow elimination of certain components to reduce the size and weight, thus improving the overall system performance. The review focuses specifically on multifunctional supercapacitors with novel mechanical, surface/interfacial, thermal, electronic, photodetection and energy harvesting/conversion functions. In addition, challenges and opportunities for further developments in the emerging field of multifunctional supercapacitors are suggested and discussed.
A comprehensive overview on the recent progress of multifunctional supercapacitors which combine energy storage capability with other functions.
Oxidizing CH4 into liquid products with O2 under mild conditions still mainly relies on metal catalysis. We prepared a series of sulfone‐modified conjugated organic polymers and found that the ...catalyst with proper SVI content (0.10) could drive O2→H2O2→⋅OH to oxidize CH4 into CH3OH and HCOOH directly and efficiently at room temperature under light irradiation. Experimental results showed that after 4 h reaction, decomposition rate and residual amounts of H2O2 were 81.21 % and 4.83 mmol gcat−1 respectively, and CH4 conversion rate was 22.81 %. Mechanism studies revealed that illumination could induce the homolytic dissociation of S=O bonds on catalyst to produce oxygen and sulfur radicals, where the ⋅O could adsorb and activate CH4, and the ⋅S could supply electrons for 1O2 to generate H2O2 and then for decomposing the H2O2 into ⋅OH timely to oxidize CH4. This research provided a novel organic catalysis approach for oxygen activation and utilization.
In a process of methane conversion photocatalyzed by the sulfone‐decorated conjugated organic polymer, S‐CTTP, light irradiation first induced the homolytic dissociation of S=O bonds in sulfone groups on the catalyst surface to generate free radicals. The radicals drive efficient conversion of 1O2 to H2O2 and then ⋅OH, for selective oxidation of adsorbed CH4 into CH3OH and HCOOH.
Sorafenib is an oral multikinase inhibitor that suppresses tumor cell proliferation and angiogenesis and promotes tumor cell apoptosis It was approved by the FDA for the treatment of advanced renal ...cell carcinoma in 2006, and as a unique target drug for advanced hepatocellular carcinoma （HCC） in 2007. Sorafenib can significantly extend the median survival time of patients but only by 3-5 months. Moreover, it is associated with serious adverse side effects, and drug resistance often develops. Therefore, it is of great importance to explore the mechanisms underlying sorafenib resistance and to develop individualized therapeutic strategies for coping with these problems. Recent studies to the primary resistance, mechanisms are underying the acquired resistance to sorafenib, such as crosstalk involving PI3K/Akt and JAK-STAT pathways, the activation of hypoxia-inducible pathways, and epithelial-mesenchymal transition. Here, we briefly describe the function of sorafenib, its clinical application, and the molecular mechanisms for drug resistance, especially for HCC patients.
This paper is concerned with the robust sliding mode control (SMC) problem for a class of T-S fuzzy systems subject to both matched and mismatched uncertainties. Different from the conventional T-S ...fuzzy SMC design approach, the quantized states rather than states themselves, are utilized for the control design. By the combination of the proposed zooming-out/zooming-in adjustment policy of the quantizer sensitivity, the quantized state feedback fuzzy sliding mode control scheme is developed to ensure the stabilization of the T-S fuzzy systems. Finally, some simulation results are presented to illustrate the effectiveness of the proposed approach.
Ambient exposure to fine particulate matter (PM2.5) is known to harm public health in China. Satellite remote sensing measurements of aerosol optical depth (AOD) were statistically associated with ...in-situ observations after 2013 to predict PM2.5 concentrations nationwide, while the lack of surface monitoring data before 2013 have created difficulties in historical PM2.5 exposure estimates. Hindcast approaches using statistical models or chemical transport models (CTMs) were developed to overcome this limitation, while those approaches still suffer from incomplete daily coverage due to missing AOD data or limited accuracy due to uncertainties of CTMs. Here we developed a new machine learning (ML) model with high-dimensional expansion (HD-expansion) of numerous predictors (including AOD and other satellite covariates, meteorological variables and CTM simulations). Through comprehensive characterization of the nonlinear effects of, and interactions among different predictors, the HD-expansion parameterized the association between PM2.5 and AOD as a nonlinear function of space and time covariates (e.g., planetary boundary layer height and relative humidity). In this way, the PM2.5-AOD association can vary spatiotemporally. We trained the model with data from 2013 to 2016 and evaluated its performance using annually-iterated cross-validation, which iteratively held out the in-situ observations for a whole calendar year (as testing data) to examine the predictions from a model trained by the rest of the observations. Our estimates were found to be in good agreement with in-situ observations, with correlation coefficients (R2) of 0.61, 0.68, and 0.75 for daily, monthly and annual averages, respectively. To interpolate the missing predictions due to incomplete AOD data, we incorporated a generalized additive model into the ML model. The two-stage estimates of PM2.5 sacrificed the prediction accuracy on a daily timescale (R2 = 0.55), but achieved complete spatiotemporal coverage and improved the accuracy of monthly (R2 = 0.71) and annual (R2 = 0.77) averages. The model was then used to predict daily PM2.5 concentrations during 2000–2016 across China and estimate long-term trends in PM2.5 for the period. We found that population-weighted concentrations of PM2.5 significantly increased, by 2.10 (95% confidence interval (CI): 1.74, 2.46) μg/m3/year during 2000–2007, and rapidly decreased by 4.51 (3.12, 5.90) μg/m3/year during 2013–2016. In this study, we produced AOD-based estimates of historical PM2.5 with complete spatiotemporal coverage, which were evidenced as accurate, particularly in middle and long term. The products could support large-scale epidemiological studies and risk assessments of ambient PM2.5 in China and can be accessed via the website (http://www.meicmodel.org/dataset-phd.html).
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•Estimating historical PM2.5 in China is difficult due to lack of in-situ data.•Hindcast approaches suffers from incomplete daily coverage due to missing AOD.•We design a model with high-dimensional representation of many predictors of PM2.5.•We generate daily PM2.5 maps with a spatial resolution of 0.1° in China, 2000–2016.•The spatiotemporally continuous estimates are well correlated with in-situ PM2.5.
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