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The bidirectional asymmetric transmission (BAT) meta‐devices have attracted widespread attention as an emerging display, encryption, and information storage platform. Generally, the multiplexing capability of BAT meta‐devices determines the upper limit of the loading capacity of multi‐task integrated systems. However, existing BAT meta‐devices still depend on structural properties and the arrangement of meta‐atoms, limiting the number of manipulated channels, operating frequency, and polarization combinations. Herein, a universal BAT meta‐device, enabling bidirectional eight‐phase‐channel asymmetric transmission, composed of bilayer spatially cascaded birefringent metasurfaces (BMs) is proposed to allow for arbitrary polarization combination via the inverse design method and validated in the microwave region. In addition, the polarization multiplexing capabilities of BAT meta‐devices are further extended via a Lego‐like physical mechanism. The proposed design strategy may facilitate BAT meta‐devices functional innovation and advanced application deployment in holographic images, duplex communication, and secret‐key‐sharing data encryption. [ABSTRACT FROM AUTHOR]

This paper presents a fuzzy sliding mode control method for voltage control of islanded AC/DC hybrid microgrid. The T‐S fuzzy model is utilized to approximate initial non‐linear dynamic model of the microgrid. The fuzzy rules and membership functions are designed according to the coupling relationship between AC part and DC part. To reduce the influence of external disturbance and cyber‐attacks, an integral sliding mode controller is considered. Furthermore, a sufficient condition is proposed with H∞${H}_\infty $ attenuation performance to ensure the asymptotic stability of sliding motion. The set of gain matrices can be acquired via solving the linear matrix inequalities deduced from the Lyapunov stability analysis. The reachability to the proposed sliding mode surface can be guaranteed via switching control law based on a Lyapunov function. In addition, to eliminate chattering performance of the sliding mode control theory, the fuzzy logic controller is designed to optimize the switching region in boundary layers of saturation functions. Finally, the simulation results for the islanded AC/DC hybrid microgrid are implemented to verify the robustness and effectiveness of the designed fuzzy sliding mode control method. [ABSTRACT FROM AUTHOR]

Integrated radiation‐type metasurfaces (RA‐M) have gained importance in the development of next‐generation wireless communications and integrated electronics. They facilitate advanced electromagnetic (EM) wave control with a single radiation aperture. However, most RA‐Ms fail to simultaneously decouple the amplitude, phase, and polarization information of the spatial radiation wavefront owing to the intrinsic restrictions of the meta‐radiator and limited design strategy. This study proposes and demonstrates a full‐space non‐interleaved RA‐M platform capable of precise complex‐vector‐field (CVF) Jones vector reconstruction of both near and far fields in the microwave region. The method is based on the global interaction of linear‐polarized (LP) meta‐radiators, which are organized via the LP‐basis inverse design methodology; thus, the near‐ and far‐field Jones vectors of the radiated wavefront can be subjected to customized reconstruction. The existing unidirectional meta‐radiators are further pushed to bidirectional spaces, facilitating diverse full‐space multiplexing integrated meta‐devices, such as bidirectional multi‐polarization routers and full‐space vectorial hologram modulators. The proposed RA‐M unlocks the unequaled potential of radiated CVF, thereby paving a promising pathway for integrated electronic device technologies. [ABSTRACT FROM AUTHOR]

The all‐optical diffractive deep neural networks (D2NNs) framework as a hardware platform is demonstrated to implement various advanced functional meta‐devices with high parallelism and high processing speed. However, the design methodology merging trainable polarization modulation neurons into the D2NNs, which potentially possess higher integration and more task‐loading capacity, is not yet fully explored. Here, the matrix diffractive deep neural networks (M‐D2NNs) are proposed to deploy polarization‐sensitive Jones matrix metasurfaces into the all‐optical polarization multiplexing networks to perform sophisticated inference tasks as well as inverse designs for advanced functional meta‐devices. Three polarization multiplexing meta‐devices with advanced functionalities are implemented by the M‐D2NNs, that is, high task‐capacity integration classification, non‐interleaved high‐efficiency Jones matrix eight‐channel regulation, and custom‐polarization information cryptographic multiplexing. The M‐D2NNs are demonstrated to provide a new strategy to merge polarization into electromagnetic and optical field modulators by Jones matrix metasurfaces, which may drive the evolution of all‐optical networks toward multi‐task integration and more advanced functional devices. [ABSTRACT FROM AUTHOR]

Metasurface‐based vectorial holography manifests itself as an advanced platform for large‐capacity information storage, holographic display, and cryptography. However, a convenient and effective reconfigurable vectorial hologram generation mechanism still remains a challenge. Here, a rotation‐driven reconfigurable vectorial holography scheme is developed via a dual‐layer hybrid metasurface device, in which radiation‐type and birefringent metasurfaces are cascaded hybridly. Thus, reconfigurable and highly customizable intensity and polarization response of holograms in the 3D space is achieved. Rotatable radiation‐type metasurface (RTM) serves as an incidence‐wavefront modulator to excite the non‐rotatable birefringent metasurface (BM). The gradient descent optimization inverse design method is introduced to achieve the high‐efficiency reconstruction of the Jones vector and Jones matrix distribution on both RTM and BM. On this basis, numerical analysis and experimental verification of 3‐D reconfigurable vectorial holography are demonstrated in the microwave region. This scheme implies a new paradigm for 3‐D reconfigurable vectorial holography and can lead to advances in high‐capacity optical display, switchable meta‐devices, and cryptography. [ABSTRACT FROM AUTHOR]

The 1 : 2 reaction of the imidazole‐based dithiolate (2) with GeCl2 • dioxane in THF/TMEDA gives 3, a TMEDA‐complexed dithiolene‐based germylene. Compound 3 is converted to monothiolate‐complexed (5) and N‐heterocyclic carbene‐complexed (7) germanium(II) dithiolene complexes via Lewis base ligand exchange. A bis‐dithiolene‐based germylene (8), involving a 3c–4e S‐Ge‐S bond, has also been synthesized through controlled hydrolysis of 7. The bonding nature of 3, 5, and 8 was investigated by both experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM), becomes a main public health issue worldwide due to the rapid increase in DM patient numbers. The dysfunction of endothelial progenitor cells (EPCs) in DM patients plays a critical role in endothelial repair and the progression of DM‐related vascular complications. Loxenatide is an a glucagon‐like peptide 1 receptor agonist, which is used to control glycemic in type 2 diabetes patients. However, the role of Loxenatide in EPCs remains to be investigated. EPCs were isolated, characterized, and treated with Loxenatide, high‐glucose, or 3‐TYP. quantitative real‐time polymerase chain reaction, flow cytometry, western blot, and cell counting kit‐8 assay were employed to validate the expression of gene and protein expressions and cell viability, respectively. Application of Seahorse XFp to measure oxygen consumption and mitochondrial membrane potential (MMP) were measured by Seahorse XFp and MMP assay. Loxenatide attenuated high‐glucose‐induced reactive oxygen species (ROS) production and mitochondrial‐dependent apoptosis of EPCs in a concentration‐dependent manner. The EPC mitochondrial respiration dysfunction induced by high glucose was also repressed by the loxenatide treatment. The protection effect of Loxenatide on EPCs against high‐glucose was applied by activating the sirtuin 3 (SIRT3)/Foxo3 signaling pathway. We demonstrated the regulatory role of Loxenatide in mitochondrial dysfunction and apoptosis of EPCs. We elucidated that Loxenatide protects EPC from high‐glucose‐induced apoptosis via ROS‐mediated mitochondrial pathway through the SIRT3/Foxo3 signing pathway. This may provide a new therapeutical target for the treatment of DM‐related vascular complications. [ABSTRACT FROM AUTHOR]

Biomass aerogels with superior sustainability, high compressibility, and resilience are highly attractive for diverse technological applications. Anisotropic fungus aerogels derived from natural Pleurotus eryngii with excellent compressibility and resilience are obtained through a facile and environmentally friendly top‐down approach. The preserved alignment of polysaccharide fibers inside fungus aerogels leads to remarkable anisotropic mechanical and thermal insulation properties. The cross‐links generated via facile chemical modification endow fungus aerogels with excellent compressibility and resilience (deformation recovery rate of ≥96% even when the compression strain is ≥90%). Moreover, via a facile hydrophobic silanization treatment, the elastic aerogels can be endowed with excellent superhydrophobicity and water resistance. It is anticipated that this facile and sustainable strategy will provide technical support for scalable production of fungus‐based aerogels with excellent compressibility and resilience, unique thermal anisotropy, and superior renewability. Meanwhile, the newly developed fungus aerogels will have broad applications in durable thermal insulation and acoustic absorption materials. [ABSTRACT FROM AUTHOR]

Summary: This article considers the event‐triggered adaptive sliding mode control problem for switched systems with the exogenous disturbance and the unknown nonlinear disturbance subject to network‐induced delay. The system output is considered to be periodically sampled. First, a mode‐dependent event‐triggering scheme is proposed to decide whether the sampled system output is transmitted or not to the observer. Second, two new integral sliding surfaces depending on the state of the switching instants are designed for the observer and the error system respectively. Moreover, the sliding mode observer for the error system can compensate the effect of the nonlinearity and match the exogenous disturbance by its upper bound, which is more suitable in practical applications. Compared with the existing results, the proposed switching‐dependent sliding mode surface for the error system not only has the characteristics of the mode dependent sliding mode surface, but also we establish the relationship among the average dwell time, the triggering condition and the mode dependent sliding mode surface. The stability conditions of the sliding mode dynamics are presented, and two event‐triggered adaptive sliding mode controllers are derived to guarantee global uniform exponential stability of switched systems with a H∞$$ {H}_{\infty } $$ performance. Finally, an example is employed to show the effectiveness. [ABSTRACT FROM AUTHOR]

This article is concerned with the event‐triggered H∞$$ {H}_{\infty } $$ state estimation problem of delayed neural networks. A new event‐triggered scheme is designed based on the estimation error, which makes a balance between the state estimator performance and network communication bandwidth in accordance with practical requirement. An auxiliary function‐type free‐matrix‐based integral inequality is proposed, which can fully link the relationship among time‐varying delay and system states due to additional delay‐product‐type matrices. Based on these condiments, sufficient condition is established to guarantee the estimation error system to be asymptotically stable and satisfies the H∞$$ {H}_{\infty } $$ performance. Meanwhile, the desired event‐triggered estimator gains are derived in terms of linear matrix inequalities. A numerical example is illustrated to demonstrate the effectiveness of the obtained methods. [ABSTRACT FROM AUTHOR]

This article investigates the event‐triggered sliding mode control problem for uncertain networked switched systems with the external nonlinear disturbance. First, to reduce the utilization of the network bandwidth, a novel mode‐dependent continuous‐time event‐triggering scheme (ETS) including the state triggering error is proposed. A switching‐dependent auxiliary function called the triggering sliding mode function is constructed, which prevents the controller from using the extra information (the continuous state). Then, a novel switching‐dependent integral‐type switching function that depends on the states of the switching instants and includes an exponential term is proposed. Obtaining the boundary of the sliding mode region benefits from the exponential term for continuous‐time systems. Then, an event‐triggered sliding mode controller is designed, which makes the networked switched systems practical stability, and attains the sliding region around the specified sliding surface. When the constant threshold of the triggering scheme is zero, the system state can converge to zero as time goes to infinity. Moreover, it is proved that the Zeno behavior can be avoided under the proposed continuous‐time ETS. Finally, the effectiveness of the proposed method is shown by a switched Chua's circuit system. [ABSTRACT FROM AUTHOR]

A series of reactions between Lewis bases and an imidazole‐based dithione dimer (1) has been investigated. Both cyclic(alkyl)(amino)carbene (CAAC) (2) and N‐heterocyclic carbene (NHC) (4), in addition to N‐heterocyclic silylene (NHSi) (6), demonstrate the capability to cleave the sulphur–sulphur bonds in 1, giving carbene‐stabilized dithiolene (L0) zwitterions (3 and 5) and a spirocyclic silicon–dithiolene compound (7), respectively. The bonding nature of 3, 5, and 7 are probed by both experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

Background and purpose: This study aimed to investigate geographical differences in the clinical features of Guillain–Barré syndrome (GBS) between patients from our region in Eastern China and patients from other areas. Methods: A total of 595 patients fulfilling the diagnostic criteria ​for GBS or its variants were included from two large hospitals located in Eastern China. Data collection included demographics, antecedent events, clinical presentation and signs, electrophysiological subtypes, treatment, complications during hospitalization, clinical severity at nadir, and outcome at 12 months, and these data were compared to data from a study conducted in Southern China and the Europe/Americas section of the International GBS Outcome Study. Results: The median (interquartile range) age of patients was 50 (36–61) years, the ratio of men to women was 1.2, and 49% of patients had antecedent events. Patients in our region of Eastern China had pure motor predominant GBS (158/340, 46%) and 30% (103/340) had complications during hospitalization. Patients aged over 60 years had a lower frequency of antecedent infections and single, axonal subtypes, but higher disability scores at entry, nadir, and 12 months. When compared with the Europe/Americas data, our patients had a lower frequency of antecedent infection (46% vs. 63%), cranial nerve involvement (43% vs. 49%), sensory deficits (45% vs. 69%), pain (19% vs. 57%) and mechanical ventilation (11% vs. 17%), but a higher frequency of axonal subtype (35% vs. 6%). There was a higher frequency of patients with antecedent gastroenteritis (16% vs. 8%), mechanical ventilation (11% vs. 8%) and axonal subtypes (35% vs. 19%) in our region in Eastern China than in Southern China. Conclusions: Patients with GBS in Eastern China showed significant clinical heterogeneity and differences when compared to other geographic areas. [ABSTRACT FROM AUTHOR]

Summary: This article investigates the problem of event‐triggered control for network descriptor systems with randomly occurring uncertainties and nonlinearities. First, a novel adaptive event‐triggered scheme (AETC) is introduced to save more limited network resource. Second, by considering the network‐induced delay, randomly occurring uncertainties and nonlinearities, and the adaptive transmission scheme, a delay system method is used to build a novel time‐varying delay system model. Based on this model and Lyapunov function technology, sufficient stability conditions to verdict admissible and stabilization conditions to codesign the controller gain and the weighting matrix of the adaptive transmission scheme are obtained in terms of linear matrix inequalities. Finally, a numerical simulation example and a comparing example are employed to illustrate the effectiveness and the advantageous performances of the proposed AETC. [ABSTRACT FROM AUTHOR]

Summary: This article is concerned with the problem of the event‐triggered H∞ control for network descriptor systems with time‐delay under a novel adaptive event‐triggering scheme. First, to save more limited communication resource, a novel adaptive event‐triggering scheme is introduced to adaptively adjust the communication threshold. Second, by considering the network‐induced delay, the system's time‐varying delay, and the transmission scheme, a delay system method is used to build a novel time‐varying delay system model. Based on this model and Lyapunov function technology, sufficient stability conditions with the H∞ disturbance performance to verdict admissible and stabilization conditions to codesign the controller gain are obtained in terms of linear matrix inequalities. Then, an event‐triggered H∞ controller is proposed to stabilize descriptor systems with time‐delay. Finally, a numerical simulation example and a comparing example are employed to illustrate the effectiveness and the advantageous performances of the proposed adaptive event‐triggering scheme. [ABSTRACT FROM AUTHOR]

Reaction of carbene‐stabilized disilicon (1) with the lithium‐based dithiolene radical (2.) affords the first dianionic silicon tris(dithiolene) complex (3). Notably, the formation of 3 represents the unprecedented utilization of carbene‐stabilized disilicon (1) as a silicon‐transfer agent. The nature of 3 was probed by multinuclear NMR spectroscopy, single‐crystal X‐ray diffraction, and DFT computations. [ABSTRACT FROM AUTHOR]

Objective: To investigate the spectrum of antecedent infections in Chinese patients with Guillain‐Barré syndrome (GBS) and analyze the infections‐related clinical phenotypes locally. Methods: A prospective case‐control study of 150 patients diagnosed with GBS and age‐ and sex‐matched neurological and healthy controls was performed to investigate recent infections of 14 pathogens serologically and collect the clinical data during a follow‐up of 12 months. Results: In total, 53% of patients with GBS had a positive serology for recent infection, including Campylobacter jejuni (27%), influenza A (17%) and B (16%), hepatitis A virus (5%), dengue virus (3%), cytomegalovirus (3%), Epstein–Barr virus (3%), Mycoplasma pneumoniae (2%), herpes simplex virus (2%), varicella‐zoster virus (1%), and rubella virus (1%). Serology for infections of hepatitis E virus, Haemophilus influenzae, and Zika virus was negative. There was a higher frequency of C. jejuni, influenza A, influenza B, and hepatitis A virus infections in GBS patients than both the neurological and healthy controls. C. jejuni infection was more frequent in younger GBS patients and was associated with antibodies against GM1, GalNAc‐GD1a, and GM1:galactocerebroside complex. Influenza B infection was associated with a pure motor form of GBS. Interpretation: C. jejuni, influenza A, influenza B, and hepatitis A virus serve as the most common cause of antecedent infections in GBS locally. Influenza B‐related GBS may represent a pure motor phenotype. Differences in the infectious spectrum worldwide may contribute to the geographical clinical heterogeneity of GBS. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates event‐triggered sliding mode control for descriptor systems subject to networked‐induced delay. For handling disturbance and saving data transmission in networks for descriptor systems, sliding model control and event‐triggered control are combined, whereas how to combine them to design a stable controller is challenging due to the complexity of descriptor systems. Firstly, a new discrete event‐triggered scheme is introduced for deciding whether sampled data is sent out or not for networked‐based descriptor systems. Secondly, integral‐type switching surface and event‐triggered scheme are integrated resulting in a novel time‐delay system. The existence condition of integral‐type switching surface and the stability condition of the sliding mode dynamic are presented. An event‐triggered sliding mode controller is derived for driving the closed‐loop system trajectories to the practical switching surface in finite time. Finally, two examples are employed to show the effectiveness and advantages of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: Whereas low‐temperature (−78 °C) reaction of the lithium dithiolene radical 1. with boron bromide gives the dibromoboron dithiolene radical 2., the parallel reaction of 1. with (C6H11)2BCl (0 °C) affords the dicyclohexylboron dithiolene radical 3.. Radicals 2. and 3. were characterized by single‐crystal X‐ray diffraction, UV/Vis, and EPR spectroscopy. The nature of these radicals was also probed computationally. Under mild conditions, 3. undergoes unexpected thiourea‐mediated B−C bond activation to give zwitterion 4, which may be regarded as an anionic dithiolene‐modified carbene complex of the sulfenyl cation RS+ (R=cyclohexyl). [ABSTRACT FROM AUTHOR]

To surmount difficulty of the melt processing and deterioration of mechanical properties of polymer composites induced by high fraction of the reinforced fibers and thermal conductive fillers, polyethylene (PE)/boron nitride (BN)/polyamide 6 (PA6) and PE/BN/poly(-hydroxybenzate- co-DOPO-benzenediol dihydrodiphenyl ether terephthalate) (PHDDT) in situ microfibrillar composites were prepared through multistage stretching extrusion. The experimental results showed that both the tensile and impact strength of the PE/BN/PA6 and PE/BN/PHDDT composites were improved. Meanwhile, the thermal conductivities of the PE/BN, PE/BN/PA6, and PE/BN/PHDDT composites were also reinforced. Based on the equation proposed by Y. Agari, the new modified equations can well predict the thermal conductivity of the composites prepared through multistage stretching extrusion with different number of laminating-multiplying elements. In addition, it was found that PHDDT can act as a 'processing aid' to reduce the viscosity of the PE/BN composites. POLYM. COMPOS., 38:2663-2669, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Diagnosis of drowning remains a difficult issue in current forensic sciences. A large number of diatoms were lost by removing the supernatant after centrifugation in the conventional forensic diatom test. We developed a novel membrane filtration method to enrich diatoms from samples. A new solution using different ratios of acetic acid and eugenol is prepared to make the membrane transparent. These processes allow the diatom‐containing membrane to be visualized and identified easily by light microscopy. The tissues contaminated by water rich in diatoms were detected by the new method for the recovery of diatoms. Eleven drowning cases were analyzed by both the new method and the conventional method to compare the sensitivity of both methods. The recovery of the novel diatom test method was 54.2 ± 23.1%. The positive rate of the novel method has been proven to be superior to the conventional method in the diagnosis of drowning. [ABSTRACT FROM AUTHOR]

Reaction of carbene-stabilized disilicon ( 1) with Fe(CO)5 gives the 1:1 adduct L:SiSi[Fe(CO)4]:L (L:=C{N(2,6-Pr i2C6H3)CH}2) ( 2) at room temperature. At raised temperature, however, 2 may react with another equivalent of Fe(CO)5 to give L:Si[μ-Fe2(CO)6](μ-CO)Si:L ( 3) through insertion of both CO and Fe2(CO)6 into the Si2 core, which represents the first experimental realization of transition metal-carbonyl-mediated cleavage of a SiSi double bond. The structures and bonding of both 2 and 3 have been investigated by spectroscopic, crystallographic, and computational methods. [ABSTRACT FROM AUTHOR]

Presence of diatoms in tissues has been considered as a significant sign of drowning. However, there are limitations in the present extraction methods. We developed a new digestion method using the Lefort aqua regia solution (3:1 nitric acid to hydrochloric acid) for diatom extraction and evaluated the digestive capability, diatom destruction, and diatoms' recovery of this new method. The kidney tissues from rabbit mixed with water rich in diatoms were treated by the Lefort aqua regia digestion method ( n = 10) and the conventional acid digestion method ( n = 10). The results showed that the digestive capability of Lefort aqua regia digestion method was superior to conventional acid digestion method ( p < 0.01); the structure of diatom remained almost intact; and the recovery of diatom was comparable to the conventional acid digestion method ( p > 0.05). The Lefort aqua regia reagent is an improvement over the conventional acid digestion for recovery of diatoms from tissue samples. [ABSTRACT FROM AUTHOR]

Reaction of N-heterocyclic-carbene (NHC)-stabilized disilicon ( 1) with CuCl gave a carbene-stabilized disilicon-copper(I) chloride complex ( 2). The nature of the structure and bonding in 2 has been investigated by crystallographic, spectroscopic, and computational methods. The dynamic complexation behavior of 2 was experimentally explored by variable-temperature NMR analysis. [ABSTRACT FROM AUTHOR]

Phosphorus-containing wholly aromatic thermotropic liquid crystalline polymer (TLCP) reinforced poly(butylene terephthalate) (PBT) composites were prepared. Dynamic rheological analysis displayed that the addition of TLCP led to the decrease of the complex viscosity of PBT. While the thermal stability and tensile modulus were found to be increased distinctly, the results of dynamic mechanical analysis, isothermal crystallization, and morphological observation indicated that these changes were related to the rigid chains and in situ fibrillation of TLCP phase, and the interfacial adhesion between PBT and TLCP. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]