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We propose a hybrid beamforming architecture for near-field reconfigurable holographic surfaces (RHS) harnessed in cell-free networks. Specifically, the holographic beamformer of each base station (BS) is designed for maximizing the channel gain based on the local channel state information (CSI). By contrast, the digital beamformer at the central processing unit is designed based on the minimum mean squared error criterion. Furthermore, the near-field spectral efficiency of the RHS in cell-free networks is derived theoretically by harnessing the popular stochastic geometry approach. We consider both the phase shift error (PSE) at the RHS elements and the hardware impairment (HWI) at the radio frequency (RF) chains of the transceivers. Furthermore, we theoretically derive the asymptotic capacity bound, when considering an infinite physical size for the RHS in the near-field channel model. The theoretical analysis and simulation results show that the PSE at the RHS elements and the HWI at the RF chains of transceivers limit the spectral efficiency in the high signal-to-noise ratio region. Moreover, we show that the PSE at the RHS elements and the HWI at the RF chains of BSs can be compensated by increasing the number of BSs. Finally, we also demonstrate that the ergodic spectral efficiency based on the near-field channel model is higher than that based on the far-field channel model assumption.

Reconfigurable holographic surfaces (RHSs) constitute a promising technique of supporting energy-efficient communications. In this paper, we formulate the energy efficiency maximization problem of the switch-controlled RHS-aided beamforming architecture by alternately optimizing the holographic beamformer at the RHS, the digital beamformer, the total transmit power and the power sharing ratio of each user. Specifically, to deal with this challenging non-convex optimization problem, we decouple it into three sub-problems. Firstly, the coefficients of RHS elements responsible for the holographic beamformer are optimized to maximize the sum of the eigen-channel gains of all users by our proposed low-complexity eigen-decomposition (ED) method. Then, the digital beamformer is designed by the singular value decomposition (SVD) method to support multi-user information transfer. Finally, the total transmit power and the power sharing ratio are alternately optimized, while considering the effect of transceiver hardware impairments (HWI). We theoretically derive the spectral efficiency and energy efficiency performance upper bound for the RHS-based beamforming architectures in the presence of HWIs. Our simulation results show that the switch-controlled RHS-aided beamforming architecture achieves higher energy efficiency than the conventional fully digital beamformer and the hybrid beamformer based on phase shift arrays (PSA). Moreover, considering the effect of HWI in the beamforming design can bring about further energy efficiency enhancements.

To address the low accuracy and inefficiency of current lane-change trajectory prediction methods for human-driven vehicles, this study develops a neural network lane-change trajectory prediction model with hyperparametric optimization capability using Bayesian optimization and gated recurrent units to consider the effect of lane-change intention on vehicle lane-change behavior and to predict it. The proposed model was instantiated using trajectory data of 8,721 vehicles. The results show that the overall recognition accuracy of intention recognition under the optimal input is 93.54%, and the recognition accuracy of keeping straight, left lane-change and right lane-change is 95.59%, 91.72%, and 93.30%, respectively. The root mean square errors of the predicted and actual trajectories to the left and to the right under the optimal input are 0.2582 and 0.2957, respectively. This paper demonstrates that, for the intention recognition module, the low-dimensional input enables the model to obtain high prediction accuracy, while for the trajectory prediction module, the high-latitude input enables the model to obtain a low prediction error. The developed trajectory prediction model can be used to assist in driving decision-making, path planning, and so forth.

The application of network non-orthogonal multiple access (N-NOMA) technique to coordinated multi-point (CoMP) systems has attracted significant attention due to its superior capability to improve connectivity and maintain reliable transmission for CoMP users simultaneously. Based on the concept of quasi-degraded channel for N-NOMA, this paper studies the precoding design for downlink N-NOMA scenarios with two base stations (BSs) equipped with multiple antennas. In specific, under quasi-degraded channels, simple linear precoding based N-NOMA can achieve the same minimal total transmission power as theoretically optimal but complicated dirty paper coding (DPC) scheme, when the users’ target rates and minimal transmission power of each BS are given. In this paper, the channel quasi-degradation (QD) condition is first rigorously derived for the scenario with single CoMP user and two NOMA users. The closed-form optimal precoders for N-NOMA under quasi-degraded channels are also provided. Then, based on QD condition, a novel hybrid N-NOMA (H-N-NOMA) scheme is proposed, which is a mixture of N-NOMA and conventional zero-forcing beamforming (ZFBF) scheme. Further, for the scenarios with more users, a low-complexity QD based user pairing (QDUP) algorithm is proposed, which is then combined with H-N-NOMA to make a novel scheme termed H-N-NOMA/QDUP into being. Numerical results are presented to reveal the impact factors on QD channels, and also demonstrate the superior performance of the proposed H-N-NOMA/QDUP scheme. It is shown that the proposed H-N-NOMA/QDUP scheme can effectively exploit the benefit of multi user diversity.

The aim of this paper is to reveal the importance of hybrid successive interference cancellation (SIC) and power adaptation (PA) for improving transmission robustness of uplink non-orthogonal multiple access (NOMA). Particularly, a cognitive radio inspired uplink NOMA communication scenario is considered, where one primary user is allocated one dedicated resource block, while $M$ secondary users compete with each other to be opportunistically served by using the same resource block of the primary user. Two novel schemes are proposed for the considered scenario, namely hybrid SIC with PA (HSIC-PA) scheme and fixed SIC with PA (FSIC-PA) scheme. Both schemes can ensure that the secondary users are served without degrading the transmission reliability of the primary user compared to conventional orthogonal multiple access (OMA) based schemes. The novelty of the proposed schemes compared to those existing schemes is the introduction of power adaptation. This paper presents rigorous analytical results to show that both schemes can avoid outage probability error floors without any constraints on users’ target rates in the high SNR regime, which cannot be achieved by the existing schemes. Furthermore, it is shown that the diversity gain achieved by the HSIC-PA scheme is $M$ , while that of the FISC-PA scheme is only 1. Numerical results are provided to verify the developed analytical results and also demonstrate the superior performance achieved by the proposed schemes by comparing with the existing HSIC without PA (HSIC-NPA) scheme. The presented simulation results also show that HSIC-PA scheme performs the best among the three schemes, which indicates the importance of the combination of HSIC and PA for improving transmission robustness.

An intelligent omni-surface (IOS) assisted holographic multiple-input and multiple-output architecture is conceived for $360^\circ$ full-space coverage at a low energy consumption. The theoretical ergodic rate lower bound of our non-orthogonal multiple access (NOMA) scheme is derived based on the moment matching approximation method, while considering the signal distortion at transceivers imposed by hardware impairments (HWIs). Furthermore, the asymptotically ergodic rate lower bound is derived both for an infinite number of IOS elements and for continuous aperture surfaces. Both the theoretical analysis and the simulation results show that the achievable rate of the NOMA scheme is higher than that of its orthogonal multiple access counterpart. Furthermore, owing to the HWIs at the transceivers, the achievable rate saturates at high signal-to-noise ratio region, instead of reaching its theoretical maximum.

This article investigates the performance of network non-orthogonal multiple access (N-NOMA) in a downlink coordinated multi-point (CoMP) system. In the considered N-NOMA scheme, multiple base stations (BSs) cooperatively serve a CoMP user, meanwhile, each BS serves additional NOMA users by occupying the same resource block allocated to the CoMP user. The locations of the BSs and users are modeled by stochastic geometric models and the interference from the whole network is considered. Through rigorous derivations, the outage probabilities achieved by the CoMP and NOMA users are obtained, respectively. Numerical results are provided to verify the accuracy of the analytical results and also demonstrate the superior performance of N-NOMA compared to orthogonal multiple access (OMA) based CoMP scheme.

Reconfigurable intelligent surfaces (RIS) are capable of beneficially ameliorating the propagation environment by appropriately controlling the passive reflecting elements. To extend the coverage area, the concept of simultaneous transmitting and reflecting reconfigurable intelligent surfaces (STAR-RIS) has been proposed, yielding supporting 360° coverage user equipment (UE) located on both sides of the RIS. In this paper, we theoretically formulate the ergodic sum-rate of the STAR-RIS assisted non-orthogonal multiple access (NOMA) uplink in the face of channel estimation errors and hardware impairments (HWI). Specifically, the STAR-RIS phase shift is configured based on the statistical channel state information (CSI), followed by linear minimum mean square error (LMMSE) channel estimation of the equivalent channel spanning from the UEs to the access point (AP). Afterwards, successive interference cancellation (SIC) is employed at the AP using the estimated instantaneous CSI, and we derive the theoretical ergodic sum-rate upper bound for both perfect and imperfect SIC decoding algorithm. The theoretical analysis and the simulation results show that both the channel estimation and the ergodic sum-rate have performance floor at high transmit power region caused by transceiver hardware impairments.

The aim of this paper is to present a groundwork on the delay-minimized routing problem in a vehicular ad-hoc network (VANET) where some of the vehicles are equipped with full-duplex (FD) radios. We first give the generalized delay calculation model for a multi-hop path, and prove that the Dijkstra algorithm is unable to get the delay-minimized routing path from source to destination. Then we propose two routing methods: graph-based method and deep reinforcement learning (DRL)-based method. In the graph-based method, the network topology is reformulated as an equivalent graph and then an evolved-Dijkstra algorithm is proposed. In the DRL-based method, the deep Q network (DQN) is employed to learn the shortest end-to-end path, wherein the delay is modeled as the rewards for routing actions. The graph-based method can achieve the exact minimum end-to-end delay, while the DRL-based method is more feasible due to its acceptable complexity. Finally, extensive simulations demonstrate that the DRL-based approach with proper hyper-parameters can achieve near minimum end-to-end delay, and the achieved delay has a notably decline as the number of FD nodes increases.

Radioisotope thermophotovoltaic (RTPV) generator has wide application prospects in sea, land, air, medical, electronics, and other fields. In order to better investigate the influence of alpha rays on emitters, thermophotovoltaic (TPV) cells, and other components, it is vital to find out a suitable way which can rapidly evaluate and select each of the components in TPV cells by the combination of heating and irradiation of alpha beam. In this work, a TPV cells test system, in which the tungsten emitter has been heated by the He+ ion beam experiment, has been investigated systematically. It is found that the Gaussian distribution of temperature in tungsten emitter is obtained along the radial direction under uniform distribution of He+ ion beam. The distance between emitter and TPV cells has a great effect on the radiant heat flux and temperature. The simulation results show that the TPV cells have the highest output power (~1.8 W) when the optimal distance between emitter and TPV cells is 80 mm. Moreover, as one of the prospective candidate emitters, the thermal stress of silicon carbide (SiC) emitter has also been evaluated under 400-W beam. It is feasible for He+ ion beam to rapidly evaluate and select each of components in TPV cell experiment. The work will accumulate important experience for the TPV cells test of higher electric output power and the design of RTPV generator.

Three new Ru(ii) complexes, [Ru(dtb)2PPAD](PF6)2(Ru-1), [Ru(dmob)2PPAD](PF6)2(Ru-2) and [Ru(bpy)2PPAD](PF6)2(Ru-3) (dtb = 4,4′-di-tert-butyl-2,2′-bipyridine, dmob = 4,4′-dimethyl-2,2′-bipyridine, bpy = 2,2′-bipyridine and PPAD = 2-(pyridine-3-yl)-1H-imidazo[4,5f][1.10]phenanthracene-9,10-dione), were synthesized and characterized by 1H NMR and 13C NMR spectroscopy, HRMS and HPLC. Among them, Ru-1showed excellent antimicrobial activity against Gram-positive bacteria Staphylococcus aureus(minimum inhibitory concentration (MIC) = 1 μg mL−1) and low hemolytic and cytotoxic activity. In addition, Ru-1showed obviously rapid bactericidal activity, low resistance rate, bacterial biofilm destroying activity and high biosafety in vivo. Moreover, skin infection models and a mouse model of sepsis indicated that the anti-infective efficacy of Ru-1was comparable to that of vancomycin. Mechanism exploration results showed that the antibacterial behavior is probably related with targeting of the bacterial cell membrane and inhibiting topoisomerase I.

With the ability of enhancing desired signals, Reconfigurable Intelligent Surface (RIS) is expected to be applied to vehicular networks which require ultra-reliable communications. In this letter we propose a promising RIS-assisted vehicle-to-infrastructure (V2I) network model in highway environment. Then under Rayleigh fading channels, our goal is to derive the downlink outage probability (OP) of the proposed V2I system with considering the inter-cell interference, i.e., interference from neighbor road side units (RSUs) and RISs. To achieve this intractable derivation, the probability density functions (PDFs) of desired signal power and interference-plus noise power are calculated by leveraging Gauss-Chebyshev quadrature and moment matching. Numerical results verify the accuracy of our derivation and it is shown that RISs can enhance the desired signal with causing little interference to neighbor cells, so that the OP of V2I communications can be greatly reduced.

A new method using cloud point extraction-flame atomic absorption spectrometry was established by using ammonium pyrrolidine dithiocarbamate as a chelating agent and the cloud point phenomenon of a complexed anion-non-ionic surfactant mixture (Sodium dodecyl sulfate-Triton X-114 mixture). It was used for determining the morphology of chromium in the water and sediments of Haidian Creek. The experimental conditions inorganic electrolytes, pH of a solution, dosage of reagent, the temperature of a water bath, and heating time were optimized according to their effect on the determination of absorbance. The interference of common coexisting ions is discussed. The results show that under the optimized conditions, the standard curve for Cr(III) and Cr(VI) were both linear in the range of 0–9 × 10-3μg/L. The detection limits for Cr(III) and Cr(VI) were 2.3 and 2.7 μg/L, the correlation coefficients of the standard curve were 0.9904 and 0.9911, and the relative standard deviations were 3.7% and 4.5% (C = 0.04 μg/mL, n = 11), respectively. Compared with the common coexisting ions, Fe3+produced greater interference that cannot be neglected. A hybrid masking agent was prepared by mixing diethyltriaminepentaacetic acid and 30% triethanolamine solution at 1:25 ratio and then used in experiments. It could mask the interference of Fe3+in the samples. The proposed method was successfully applied in the determination of chromium in water and sediment samples collected from Haidian Creek. It had recovery rates of 86%–98% and 90%–104% for Cr(VI) and Cr(III) respectively, and it gave satisfactory results.

Nonthermal plasma is a promising way to achieve one-step partial oxidation of methane to methanol (MTM) under ambient conditions. Double dielectric barrier discharge (DDBD) possesses a glow-like discharge character to activate inert CH4molecules and protect methanol from overoxidation. Herein, we perform an MTM reaction in CH4/O2plasma in DDBD reactors for the first time, which exhibited the advantages of high methanol selectivity and methanol yield compared to single dielectric barrier discharge (SDBD). Glow-like mode discharge was observed in the DDBD, while filamentary mode discharge was obtained in the SDBD. By varying the discharge length, discharge gap, and discharge power, the performance of MTM was optimized, and outstanding outcomes compared to prior literature were achieved. Kinetic analysis and optical emission spectroscopy (OES) were performed to gain insight into the reaction mechanism of the MTM reaction. It can be deduced that methanol is more likely to be generated in the DDBD, attributed to the high proportion of CH3radicals in all CHxradicals, which are capable of producing methanol through collisions with oxygen related radicals. In addition, the low oxidizing ability and the restricted carbon–carbon coupling in the DDBD promote methanol selectivity and yield.

Colorectal cancer (CRC) has long been known for its tight association with chronic inflammation, thought to play a key role in tumor onset and malignant progression through the modulation of cancer stemness. However, the underlying molecular and cellular mechanisms are still largely elusive. Here we show that the IL-6/STAT3 inflammatory signaling axis induces the deacetylation of FRA1 at the Lys-116 residue located within its DNA-binding domain. The HDAC6 deacetylase underlies this key modification leading to the increase of FRA1 transcriptional activity, the subsequent transactivation of NANOGexpression, and the acquisition of stem-like cellular features. As validated in a large (n= 123) CRC cohort, IL-6 secretion was invariably accompanied by increased FRA1 deacetylation at K116 and an overall increase in its protein levels, coincident with malignant progression and poor prognosis. Of note, combined treatment with the conventional cytotoxic drug 5-FU together with Tubastatin A, a HDAC6-specific inhibitor, resulted in a significant in vivo synergistic inhibitory effect on tumor growth through suppression of CRC stemness. Our results reveal a novel transcriptional and posttranslational regulatory cross-talk between inflammation and stemness signaling pathways that underlie self-renewal and maintenance of CRC stem cells and promote their malignant behavior. Combinatorial treatment aimed at the core regulatory mechanisms downstream of IL-6 may offer a novel promising approach for CRC treatment.

In the high‐latitude thermosphere and ionosphere the Joule (frictional) heating rate is related to both conductivity and electric field. Thus, an accurate calculation of the Joule heating rate requires self‐consistent specifications of high‐latitude particle precipitation and ion convection patterns. However, general circulation models usually use uncorrelated empirical models to specify high‐latitude particle precipitation and ion convection separately and independently. Here, studies have been conducted to examine the significance of the appropriate spatial alignment of the precipitation and ion convection patterns to the energy input estimation for the upper atmosphere. As shown in Defense Meteorological Satellite Program satellite observations, a close alignment between the particle poleward boundary (PPB) and the convection reversal boundary (CRB) can be identified when the interplanetary magnetic field is strongly southward. To illustrate the importance of this alignment, a comparison between two Global Ionosphere‐Thermosphere Model runs has been conducted. In the first case, the uncorrelated empirical models were used in Global Ionosphere‐Thermosphere Model to specify the high‐latitude electrodynamics. In the second case, the PPB was adjusted to be approximately coincident with the CRB. The alignment between the PPB and the CRB causes changes in the Joule heating distribution and a 50% enhancement of hemispheric integrated Joule heating under extreme conditions. The effect of the alignment on Joule heating and neutral density has also been investigated preliminarily during the 5 August 2011 geomagnetic storm. From observations the displacement between the particle and potential patterns is usually within 1–2° when southward Bzis dominantThe displacement between the convection reversal boundary and the particle boundary from empirical models can be more than 10°After appropriately aligning the particle and potential patterns, the total Joule heating increases up to 50% under extreme conditions

Background: Several randomized clinical trials showed that aspirin could decrease the incidence of preeclampsia (PE) in women at high risk, but data from sources other than traditional clinical trials that investigating the preventive effect of aspirin 75 mg on PE is still lacking, especially in mainland China. We aimed to use Chinese real-world data to estimate the preventive effect of low-dose aspirin (LDA) on PE. Methods: Clinical data of pregnant women who were at high risk of PE and had their first prenatal visit at the affiliated Taicang People’s Hospital of Soochow University during November 31, 2018 and May 10, 2021 was retrospectively analyzed. Among the 266 included pregnant women, 115 individuals treated with aspirin 75 mg per day and the other 151 without such treatment were considered as the LDA group and the control group, respectively. Results: In the LDA group, 64 (55.65%) of 115 pregnant women took aspirin before 16 weeks of gestation. Besides, 12 (10.43%) and 34 (22.52%) women developed PE in the LDA group and control group, respectively; the aspirin prophylaxis was associated with a lower risk of PE (odds ratio = 0.40, 95% confidence interval = 0.20–0.82, P= 0.0098). In addition, LDA is slightly more effective when initiated before 16 weeks of gestation or in those without chronic hypertension, when compared with their counterparts. Conclusion: Prophylaxis with 75 mg per day of aspirin in high-risk women resulted in a significantly lower incidence of PE than that in the control group.

Thoracogastric airway fistula (TGAF) is a rare and dangerous complication of esophagectomy performed for esophageal and cardiac carcinomas. Herein, we aimed to explore the feasibility and efficacy of individualized airway stent implantation for the treatment of TGAF after esophagectomy. Based on different TGAF types and relevant data on chest computed tomography, customized airway-covered stents were positioned so as to cover the entrance to the fistula by an interventional radiologist using fluoroscopic guidance. Of the 63 patients with TGAF, 12 had thoracogastric-tracheal fistulas, 14 had thoracogastric-carinal fistulas, 21 had thoracogastric-left main bronchial fistulas, 15 had thoracogastric-right main bronchial fistulas, and 1 had a thoracogastric-right intermediate bronchial fistula. The following different stent types were placed: 7 straight self-expandable covered metallic stents, 2 hinged self-expandable covered metallic stents, 41 Y-shaped self-expandable covered metallic stents, and 13 large Y and small Y paired self-expandable covered metallic stents. In all 59 cases (93.65 %), the implantation was successful at the first attempt, with the procedure times ranging from 5 to 10 min. Esophagograms with water-soluble iodinated contrast showed that the fistulae were completely covered with no contrast flowing into the airways and lungs, and with the stents fully expanded. We recorded four cases (6.35 %) of incomplete or recurrent fistula closure. Customized airway-covered stents may be an appropriate palliative therapy for patients with thoracogastric airway fistula who are unfit for surgery or have a high postoperative risk.

The surge of antibiotic resistance in Staphylococcus aureuscalls for novel drugs that attack new targets. Developing antimicrobial peptides (AMPs) or antivirulence agents (AvAs) is a promising strategy to tackle this challenge. However, AMPs, which kill bacteria by disrupting cell membranes, suffer from low stability and high synthesis cost, while AvAs, which inhibit toxin secretion, have relatively poor bactericidal activity. Here, to address their respective shortcomings, we combined these two different antibacterial activities on the same molecular scaffold and developed a Ru-based metalloantibiotic, termed Ru1. Notably, Ru1exerted remarkable bactericidal activity (MICS= 460 nM) and attenuated bacterial virulence as well. Mechanistic studies demonstrated that Ru1had two independent targets: CcpA and bacterial membrane integrity. Based on its dual mechanism of action, Ru1effectively overcame S. aureusresistance and showed high efficacy in a mouse infection model against S. aureus. This study provides a promising approach to confronting bacterial infections.

With the acceleration of industrialization and urbanization, the emission of volatile organic compounds (VOCs) has become a serious problem, so it is urgent to develop efficient methods to eliminate. Due to the high catalytic activity, strong stability and low cost, manganese-based catalysts as a kind of non-noble catalysts have been widely used in VOCs treatment, especially in abatement of VOCs by catalytic oxidation. The manganese-based catalysts with excellent properties have been widely used in VOCs removal, and a series of measures have been adopted to improve the oxidation activity of manganese-based catalysts. In this review, the effect of structure and composition of manganese-based catalysts (such as simple MnOx, mixed manganese-based metal oxides and supported manganese-based oxide catalysts) on catalytic oxidation of VOCs and the corresponding catalytic oxidation mechanism over different manganese-based catalysts are analyzed. The specific surface area (SSA), oxygen vacancies (OVs), reactive oxygen species, the valence of Mn and acid sites of manganese-based catalysts play an important role in VOCs oxidation. Finally, some challenges and suggestions are summarized and put forward for future research. This critical review is of great significance for systematic understanding and analysis of the VOCs oxidation over manganese-based catalysts, offering guidance to the preparation of highly efficient and cost-effective manganese-based catalysts for VOCs oxidation.

The high‐latitude dawn‐dusk asymmetrical distribution of the Mean Total Electron Content (MTEC) in the northern hemisphere was statistically investigated using Global Navigation Satellite System (GNSS) vertical TEC data in 2014. In the geomagnetic latitude (MLAT)/geomagnetic local time (MLT) coordinate system, the local time of 0 hr ≤ MLT < 12 hr is defined as the dawn, and 12 hr ≤ MLT < 24 hr is defined as the dusk at MLAT is greater than 70°. The sunlit high‐density plasma at lower latitudes in the postnoon sector is the primary source of the asymmetrical MTEC distribution that the duskside MTEC is larger than the dawnside. Except for summer, the diurnal variations of the dusk‐dawn difference (DMTEC) and dusk‐dawn ratio (DDR) have two peaks and two valleys. The DMTEC and DDR also have significant seasonal variation, which is the greatest in spring (2.9TECu and 22.2%) and the smallest in summer (1.0TECu and 9.2%). The DMTEC and DDR depend significantly on the Kp index and the direction of interplanetary magnetic field (IMF). Except for the DMTEC in spring, the DMTEC and DDR are larger during disturbed times than during quiet times. Except for IMF Bz > 0 in summer, the DMTEC and DDR are larger when IMF By < 0 than those when IMF By > 0, especially in spring and winter. The high‐latitude dawn‐dusk asymmetrical distribution of ionospheric plasma in the northern hemisphere was observed based on Global Navigation Satellite System TEC dataSources of the sunlit high‐density plasma at lower latitudes in the postnoon sector are responsible for the asymmetrical distributionThe direction of IMF By and Kp index exert a significant effect on the dawn‐dusk asymmetry distribution The high‐latitude dawn‐dusk asymmetrical distribution of ionospheric plasma in the northern hemisphere was observed based on Global Navigation Satellite System TEC data Sources of the sunlit high‐density plasma at lower latitudes in the postnoon sector are responsible for the asymmetrical distribution The direction of IMF By and Kp index exert a significant effect on the dawn‐dusk asymmetry distribution

To examine if the improvement of the molecular flexibility for the reductive-amination of oxidized alginate derivative (RAOA) through chemical modification could be conducive to the enhancement of alginate electrospinnability, we attempted to use the electrospinning technology to develop the alginate derivative electrospun composite nanofibers that can load the hydrophobic anti-inflammatory drug, ibuprofen, with the aid of polyvinyl alcohol (PVA). The synthesized RAOA was examined by FT-IR spectrometer, 1H NMR spectrometer and fluorescence spectrophotometer. Furthermore, the effects of surface tension, electrical conductivity and rheological properties of the RAOA/PVA blend solution on the electrospinning property and fiber morphology of the resultant RAOA/PVA electrospun composite nanofibers were explored by surface tension meter, conductivity meter, rheometer and SEM. Subsequently, the drug loading and release mechanism of ibuprofen from the RAOA/PVA electrospun composite nanofibers were analyzed through the simulated drug release test. In addition, the cytotoxicity of the RAOA/PVA electrospun composite nanofibers was also evaluated with L929 cells by Cell Counting Kit-8 (CCK-8) assay. Experimental results showed that the hydrophobic side groups were successfully grafted onto the alginate backbone by the oxidation-reductive amination reaction, which destroyed the intramolecular hydrogen bond of the raw sodium alginate (SA), thus enhancing the molecular flexibility and colloidal interface activity of RAOA. So the RAOA could exhibit good amphiphilic property with the critical aggregation concentration (CAC) of 0.42 g/L in NaCl solution, and form the self-assembled micelle with the average hydrodynamic diameter of 615 nm (PDI = 0.24) and zeta potential at about −66.5 mV. Although the oxidation-reductive amination reaction for the modification of RAOA could not fundamentally achieve the generation of bead-free nanofibers by electrospinning of single RAOA aqueous solution, it could improve the electrospinning performance of RAOA/PVA blend solution and increase its content in the RAOA/PVA electrospun composite nanofibers. Furthermore, the fabricated RAOA/PVA electrospun composite nanofibers exhibited the high encapsulation efficiency (EE) and sustained-release property in comparison with the 50/50 SA/PVA electrospun composite nanofibers, due to the good affinity of RAOA to hydrophobic ibuprofen that achieve the loading and controlled release of the hydrophobic drug. Besides, the RAOA/PVA electrospun composite nanofibers exhibited low cytotoxicity to L929 cells. Therefore, the resultant RAOA/PVA electrospun composite nanofibers, combining the structural characteristics of the electrospun nanofibers and the properties of RAOA including the good self-assembly performance, colloidal interface activity, sustained release performance and good cytocompatibility, may possess great potentials as the functional wound dressings for biomedical applications.

•New swelling-induced morpholine functionalized adamantane-containing membranes are prepared.•MAPEK membranes are first applied in VFB.•MAPEK membranes exhibit low area resistance and high membrane selectivity.•MAPEK membranes exhibit excellent energy efficiency of 91% at 80 mAcm−2.

A vanadium flow battery (VFB) is one of the most promising electrochemical energy storage technologies. However, membranes for VFBs still suffer from high cost or low conductivity and poor stability. Here, we report new quaternized anthrone-containing poly(aryl ether ketone) (QAnPEK) membranes for VFBs. QAnPEK membranes with moderate ion exchange capacity (1.26 mmol g–1) were swelling-induced in H3PO4(50 wt %) to form wider ion transport pathways that significantly enhanced membrane conductivity (e.g., 0.49 Ω cm2for the QAnPEK-virgin membrane and 0.12 Ω cm2for the swelling-induced QAnPEK-90 membrane). The bulky rigid anthrone-containing backbone provided high swelling resistance and enabled QAnPEK membranes to have high ion selectivity. As a result, QAnPEK membranes displayed low area resistance, high ion selectivity, and robust mechanical strength. The QAnPEK-90 membrane yielded excellent energy efficiencies (92.4% at 80 mA cm–2, 85.1% at 200 mA cm–2, and 80.3% at 280 mA cm–2). Moreover, QAnPEK membranes exhibited outstanding in situ and ex situ stability, for example, the VFB with the QAnPEK-40 membrane demonstrated highly stable battery performance for 3000 cycles at 160 mA cm–2. QAnPEK membranes are attractive candidates for VFB application.

The study aims to explore the clinicopathological features and whether the nonsense mutations of CLCN5gene have effect on the renal expression of CLC-5 protein and megalin/cubilin complex in children with Dent-1 disease. The clinicopathological features and genetic examination of three patients with Dent-1 disease were investigated. The expression of CLC-5 and megalin/cubilin complex in renal tissues was detected by using immunohistochemistry method. Urinary albumin, α1-microglobulin, β2-microglobulin, retinol binding protein, and calcium levels were measured by immunonephelometry. Urinary calcium and low molecular weight proteinuria (LMWP) were enhanced in three patients, and two presented with nephrotic range proteinuria. Focal glomerular obsolescence, minor tubulointerstitial injury, and focal calcification in corticomedullary junction were found in one patient. Nonsense mutations of CLCN5gene from their mothers were identified in all three patients with Dent-1 disease; however, the expression of CLC-5 protein was not decreased in renal tubular cells. As the receptor complex of albumin and LMWP reabsorption, the expression of megalin/cubilin in the brush border of proximal tubules was decreased in Dent-1 patients. Even if the renal CLC-5 protein is expressed normally, the reduced expression of megalin/cubilin in the brush border of renal proximal tubules may be helpful to understand the physiopathology of Dent-1 disease with nonsense mutations of CLCN5gene.

The coupling of γ,δ-unsaturated Fischer carbene complexes with enyne aldehyde derivatives fused to indole, imidazole, and pyrazole ring systems has been examined. The reaction leads to heterocycles fused to the hydronaphthalene ring system in a single step. The products of the reaction feature heterocycles fused either to benzene rings or to a cyclohexane ring. The product distribution correlates with the electronic richness of the heterocyclic ring. A moderate degree of diastereoselectivity was observed using heterocycles featuring chiral nitrogen substituents.

An acid-catalyzed ring-closing ynamide-carbonyl metathesis is described here. This hetero RCM methodology is applicable to the construction of carbocycles as well as heterocycles such as chromenes, quinolizidines, indolizidines, and pyrrolizidines.

The stoichiometric complex formed between bovine β-trypsin and Momordica charantia,Linn. Cucurbitaceaetrypsin inhibitor A (MCTI-A) was crystallized and its X-ray crystal structure was refined to a final Rvalue of 0.179 using data of 7.0- to 1.8-Å resolution. Combination with results on the complex of MCTI-A with porcine trypsin gives the sequence of MCTI-A definitely, of which 13 residues are conserved compared with other squash family trypsin inhibitors. Its spatial structure and the conformation of its primary binding segment from Cys3I (P3) to Glu7I (P3′), which contains a reactive scissile bond Arg5I C–Ile6I N, were found to be very similar to the other squash family proteinase inhibitors.

AbstractThe crystal structure of the complex of mung bean inhibitor lysine active fragment with bovine β-trypsin has been determined by X-ray crystallographic analysis at a resolution of 1.8 Å. Refinement of the model of the complex converged at a final R value of 0.16. From the resulting electron density map, about one-third of the residues of the inhibitor were identified and two residues, at position P4 and P2′ respectively, were found to be inconsistent with the sequence reported previously. The peptide chain of the inhibitor at the trypsin active site turns back sharply at Pro23I and forms a 9-residue reactive loop, which interacts with trypsin in a similar manner to the other families of inhibitors, suggesting an important and common role of these regions in exhibiting inhibitory activity.

Unmanned aerial vehicles (UAVs) have gained considerable interests in numerous civil applications. To push forward its potentials, cellular-connected UAVs have been introduced. Nevertheless, cellular networks face several bottlenecks such as spectrum scarcity and limited concurrent connectivity. To address these issues, non-orthogonal multiple access (NOMA) can be adopted. NOMA provides several opportunities for cellular-connected UAVs such as larger rate region, balanced performance between system throughput and fairness, and reduced delay. In this paper, we review important findings of the related studies, and outline new opportunities and challenges in NOMA for cellular-connected UAVs. Monte-Carlo simulations are then performed to analyze the new aerial user’s (AU)’s signal characteristics and evaluate the NOMA performance for co-existence of AU and terrestrial user (TU). Our preliminary results show that NOMA is a promising strategy for cellular-connected UAVs.

Objective Ozone is a colorless gas used as a disinfectant and to treat diseases by limiting the effects of bacteria, viruses, fungi, yeast, and protozoa. In this study, we investigated the clinical efficacy of ozonated water lavage and physiological saline irrigation combined with vacuum-sealed drainage (VSD) in the treatment of chronic osteomyelitis.Methods Eighteen patients (14 men and 4 women) with chronic osteomyelitis in the limbs (tibia: 13 cases; femur: 4 cases; humerus: 1 case) admitted to our hospital between April 2012 and October 2018 were selected. The patients were aged 9 to 52 years, with a mean age of 31 years. All patients underwent ozonated water lavage and physiological saline irrigation combined with VSD negative pressure closed drainage during hospitalization. The patients were followed up for 18 to 84 months, with a mean of 31 months.Results Osteomyelitis recurred in only one case of nonunion. The length of hospitalization was 18 to 29 days, with a mean of 21 days.Conclusions A combination of ozonated water lavage, physiological saline irrigation, and VSD provided good clinical effects in the treatment of chronic osteomyelitis, and thus, is recommended for such treatment.

A subset of uterine natural killer cells promotes fetal growth through regulation of growth-promoting factors by PBX1.

Interspecies nuclear transfer provides a possible alternative to clone endangered animals whose oocytes are difficult to obtain. The object of this study was to investigate the developmental competence of in vitro matured porcine oocyte using somatic cell nuclei of two different species (goat and mouse) by nuclear transfer (NT). Porcine cumulus-oocyte complexes were obtained from 2–6 mm diameter follicles of ovaries and matured in TCM-199 supplemented with 0.1% polyvinyl alcohol, 3.05 mM D-glucose, 0.91 mM sodium pyruvate, 0.57 mM L-cysteine, 0.5 μg mL-1 LH, 10 ng mL-1 EGF. After 22 h of maturation culture, the oocytes were transferred to maturation medium without hormone supplementation, and incubated for an additional 22 h. Enucleation was accomplished the first polar body and cytoplasm and a single donor cell was individually microinjected into vitelline space of the enucleated oocyte. The reconstructed embryos were electrically fused with two DC pulses of 1.1 kV/cm for 30ì sec in 0.3 M mannitol medium. The activated embryos were cultured in PZM-3 for 7 days. Fusion rate and cleavage rate of NT embryos derived from goat and mouse fetal fibroblast cells were not different from that of porcine cells. NT embryos with goat fetal fibroblast cells decreased the proportion of morula and blastocysts formation compared with NT embryos derived from porcine fetal fibroblast cells (5.2% vs 19.0%). The blastocyst developmental rate in NT embryos derived from mouse fetal fibroblast cells (17.4%) was similar to that of NT embryos with porcine fetal fibroblast cells. These results suggest that porcine cytoplasm may have species-preference as a recipient in interspecies nuclear transfer. (poster)

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.