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Recently, two-dimensional (2D) magnets have drawn substantial attention from researchers for their fascinating properties and great application potential in the fields of biomedicine, data storage, signal transfer, and energy conversion. However, the low Curie/Néel temperature of 2D magnets hinders their application. In this Perspective, we present some physical insights into enhancing the magnetic stability of 2D magnets. First, the microscope theoretical model of 2D magnets is introduced. Then, we review and analyze several effective and commonly used methods for enhancing the magnetic stability of 2D magnets. Finally, we present the perspective and summary. This Perspective presents the advanced understanding of magnetic stability in 2D materials, which can provide new opportunities for further advancement in a wide variety of applications. [ABSTRACT FROM AUTHOR]

LGBT students continue to be vastly invisible in the international higher education literature and often face hostile learning environments, both in the classroom and in the larger university environment. This study follows a narrative inquiry approach to explore and document the experiences of tongzhi–the most widely embraced identity label among individuals romantically and sexually attracted to people of their same gender in contemporary Chinese societies–students in Mainland China. We interviewed six male university students who identify as tongzhi in order to understand their educational experience, the learning environments they experience in the classroom, and their interactions with the academic staff. Despite very different individual narratives, the findings reveal a resilient student population and a strategic approach to managing complex relationships and navigating self-disclosure. We offer recommendations for future research and for practitioners invested in promoting inclusive learning environments for all students. [ABSTRACT FROM AUTHOR]

The optimal control of flow and fluid–structure interaction (FSI) systems often requires an accurate model of the controlled system. However, for strongly nonlinear systems, acquiring an accurate dynamic model is a significant challenge. In this study, we employ the deep reinforcement learning (DRL) method, which does not rely on an accurate model of the controlled system, to address the control of transonic buffet (unstable flow) and transonic buffeting (structural vibration). DRL uses a deep neural network to describe the control law and optimizes it based on data obtained from interaction between control law and flow or FSI system. This study analyzes the mechanism of transonic buffet and transonic buffeting to guide the design of control system. Aiming at the control of transonic buffet, which is an unstable flow system, the control law optimized by DRL can quickly suppress fluctuating load of buffet by taking the lift coefficient as feedback signal. For the frequency lock-in phenomenon in transonic buffeting flow, which is an unstable FSI system, we add the moment coefficient and pitching displacement to feedback signal to observe pitching vibration mode. The control law optimized by DRL can also effectively eliminate or reduce pitching vibration displacement of airfoil and buffet load. The simulation results in this study show that DRL can adapt to the control of two different dynamic modes: typical forced response and FSI instability under transonic buffet, so it has a wide application prospect in the design of control laws for complex flow or FSI systems. [ABSTRACT FROM AUTHOR]

The rupture of a micro/nano container can trigger the release of repair agents and provides the coating with a self-healing and anti-corrosion effect. However, the defect and inhomogeneity of the coating, produced by the rupture of the micro/nano container, may weaken its anti-corrosion performance. This study reports a rare protection mechanism, which optimizes the space occupying of zirconium phosphate, and the de-doping peculiarity of polyaniline without the rupture of the micro/nano container. Polyaniline/α-zirconium phosphate composites were constructed through in situ oxidation polymerization. Repair agents were added in the form of doped acids. According to the different repair agents in polyaniline/α-zirconium phosphate composites (citric ion, tartaric ion and phytic ion), the performance and protection mechanism of the composites were researched. Polyaniline/α-zirconium phosphate coating (with phytic ion) shows an excellent self-healing anti-corrosive effect, due to the large spatial structure and abundant chelating groups of the precipitation inhibitor. Considering the anti-corrosive application, the developed polyaniline/α-zirconium phosphate composite has a far-reaching influence on marine development. [ABSTRACT FROM AUTHOR]

In recent years, the two-dimensional (2D) orthorhombic SiP2 flake has been peeled off successfully by micromechanical exfoliation and it exhibits an excellent performance in photodetection. In this paper, we investigated the mechanical properties and the origin of its anisotropy in an orthorhombic SiP2 monolayer through first-principles calculations, which can provide a theoretical basis for utilizing and tailoring the physical properties of a 2D orthorhombic SiP2 in the future. We found that the Young's modulus is up to 113.36 N/m along the a direction, while the smallest value is only 17.46 N/m in the b direction. The in-plane anisotropic ratio is calculated as 6.49, while a similar anisotropic ratio (~6.55) can also be observed in Poisson's ratio. Meanwhile, the in-plane anisotropic ratio for the fracture stress of the orthorhombic SiP2 monolayer is up to 9.2. These in-plane anisotropic ratios are much larger than in black phosphorus, ReS2, and biphenylene. To explain the origin of strong in-plane anisotropy, the interatomic force constants were obtained using the finite-displacement method. It was found that the maximum of interatomic force constant along the a direction is 5.79 times of that in the b direction, which should be considered as the main origin of the in-plane anisotropy in the orthorhombic SiP2 monolayer. In addition, we also found some negative Poisson's ratios in certain specific orientations, allowing the orthorhombic SiP2 monolayer to be applied in next-generation nanomechanics and nanoelectronics. [ABSTRACT FROM AUTHOR]

Background: With remarkable success and few side effects, induction chemoimmunotherapy has been used to improve the prognosis of patients with resectable or potentially resectable non-small cell lung cancer (NSCLC), even in stage III disease. However, for patients who are medically inoperable, unresectable or refuse surgery after induction chemoimmunotherapy, it is unclear whether patients should be treated with concurrent chemoradiotherapy (cCRT) or radiotherapy (RT) alone considering patient safety and tolerability. This study aimed to determine whether cCRT is safe and superior to RT alone after chemoimmunotherapy for stage III NSCLC. Methods: Patients diagnosed with stage III NSCLC who received chemoimmunotherapy followed by cCRT/RT alone without surgery at Tianjin Cancer Hospital between November 2018 to December 2021 were retrospectively collected. Patients were divided into two groups: induction chemoimmunotherapy followed by cCRT (cCRT cohort) or RT alone (RT alone cohort). Kaplan-Meier method was used to estimate survival. Univariate and multivariate Cox regression models were adopted to estimate risk factors for PFS. Results: Sixty-five patients were included, with 44 (67.7%) received RT alone and 21 (32.3%) received cCRT. Patients in the cCRT group had significantly prolonged PFS (HR = 0.155, p = 0.004), LPFS (HR = 0.225, p = 0.029) and DMFS (HR = 0.028, p = 0.006) than those in the RT alone group. Albeit nonsignificant, a trend toward improved OS (HR = 0.030, p = 0.069) was also observed in the cCRT group. The multivariate analysis further confirmed that cCRT (HR = 0.141, p = 0.008) was the independent factor for promoting a favorable PFS. Treatment-related adverse events were similar between groups (p > 0.05). Patients with consolidation immunotherapy exhibited a trend of improved PFS (HR = 0.398, p = 0.274) and numerically better OS (HR = 0.018, p = 0.209) compared with those without. Conclusions: For patients with unresectable stage III NSCLC, cCRT following chemoimmunotherapy appears to be safe and may prolong survival compared with radiotherapy alone. Further investigations on the combination of chemoimmunotherapy and CRT are warranted. [ABSTRACT FROM AUTHOR]

A biphenylene network is a novel 2D allotropy of carbon with periodic 4-6-8 rings, which was synthesized successfully in 2021. In recent years, although the mechanical properties and thermal transport received a lot of research attention, how to open the Dirac cone in the band structure of a biphenylene network is still a confused question. In this work, we utilized uniaxial and biaxial lattice strains to manipulate the electronic properties and phonon frequencies of biphenylene, and we found an indirect band gap under 10% biaxial strain through the first-principles calculations. This indirect band gap is caused by the competition between the band-edge state A and the Dirac cone for the conduction band minimum (CBM). Additionally, the lightest carrier's effective mass in biphenylene is 0.184 m0 for electrons along x (Γ→X) direction, while the effective mass for holes shows a remarkable anisotropy, suggesting the holes in the tensile biphenylene monolayer are confined within a one-dimensional chain along x direction. For phonon dispersion, we discovered that the Raman-active A g 3 phonon mode shows a robust single phonon mode character under both compressive and tensile strain, but its frequency is sensitive to lattice strain, suggesting the lattice strain in biphenylene can be identified by Raman spectroscopy [ABSTRACT FROM AUTHOR]

Two-dimensional materials have been developed as novel photovoltaic and photocatalytic devices because of their excellent properties. In this work, four δ-IV–VI monolayers, GeS, GeSe, SiS and SiSe, are investigated as semiconductors with desirable bandgaps using the first-principles method. These δ-IV–VI monolayers exhibit exceptional toughness; in particular, the yield strength of the GeSe monolayer has no obvious deterioration at 30% strain. Interestingly, the GeSe monolayer also possesses ultrahigh electron mobility along the x direction of approximately 32,507 cm2·V−1·s−1, which is much higher than that of the other δ-IV–VI monolayers. Moreover, the calculated capacity for hydrogen evolution reaction of these δ-IV–VI monolayers further implies their potential for applications in photovoltaic and nano-devices. [ABSTRACT FROM AUTHOR]

In this study, based on first-principles calculation, the structural, electronic, interfacial, and optical properties of two-dimensional (2D) semiconductor vertical heterostructure constructed by g-GaN and Mg(OH)2 are addressed. The g-GaN/Mg(OH)2 heterostructure is discovered to be formed by van der Waals (vdW) forces and possesses a type-II band structure which can promote the separation of photogenerated electron–holes constantly. At the same time, the calculated band edge positions of the heterostructure are decent to induce the oxidation and reduction reactions for water splitting at pH 0. Gibb's free energy change in the redox reaction for the g-GaN/Mg(OH)2 vdW heterostructure is further investigated that the heterostructure can act as a suitable catalyst in hydrogen evolution reaction and oxygen evolution reaction for water splitting. The charge-density difference and the potential drop are calculated across the interface of the g-GaN/Mg(OH)2 vdW heterostructure, and the potential drop can induce a large built-in electric field, which is also a boost to prevent the recombination of the photogenerated charges. Finally, the applied external biaxial strain is studied that it can improve the optical absorption performance of the g-GaN/Mg(OH)2 vdW heterostructure. This study provides a possibility of method to design the 2D vdW heterostructure as a photocatalyst to decompose water. [ABSTRACT FROM AUTHOR]

Neurological symptoms are prevalent in both the acute and post-acute phases of coronavirus disease 2019 (COVID-19), and they are becoming a major concern for the prognosis of COVID-19 patients. Accumulation evidence has suggested that metal ion disorders occur in the central nervous system (CNS) of COVID-19 patients. Metal ions participate in the development, metabolism, redox and neurotransmitter transmission in the CNS and are tightly regulated by metal ion channels. COVID-19 infection causes neurological metal disorders and metal ion channels abnormal switching, subsequently resulting in neuroinflammation, oxidative stress, excitotoxicity, neuronal cell death, and eventually eliciting a series of COVID-19-induced neurological symptoms. Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for mitigating COVID-19-induced neurological symptoms. This review provides a summary for the latest advances in research related to the physiological and pathophysiological functions of metal ions and metal ion channels, as well as their role in COVID-19-induced neurological symptoms. In addition, currently available modulators of metal ions and their channels are also discussed. Collectively, the current work offers a few recommendations according to published reports and in-depth reflections to ameliorate COVID-19-induced neurological symptoms. Further studies need to focus on the crosstalk and interactions between different metal ions and their channels. Simultaneous pharmacological intervention of two or more metal signaling pathway disorders may provide clinical advantages in treating COVID-19-induced neurological symptoms. [ABSTRACT FROM AUTHOR]

Background: Approximately 80% of patients with blunt thoracic aortic injury (BTAI) die before reaching the hospital. Most people who survive the initial injury eventually die without appropriate treatment. This study analyzed and reported the treatment strategy of a single center for BTAI in the last 10 years and the early and middle clinical results. Methods: This retrospective study included patients diagnosed with BTAI at Xijing Hospital from 2013 to 2022. All inpatients with BTAI aged ≥ 18 years were included in this study. The clinical data, imaging findings, and follow-up results were retrospectively collected and analyzed. The Kaplan–Meier curve and multivariate logistic regression were used to compare survivors and nonsurvivors. Results: A total of 72 patients (57% men) were diagnosed with BTAI, with a mean age of 54.2 ± 9.1 years. The injury severity score was 24.3 ± 18, with Grade I BTAI1 (1.4%), Grade II 17 (23.6%), Grade III 52 (72.2%), and Grade IV 2 (2.8%) aortic injuries. Traffic accidents were the main cause of BTAI in 32 patients (44.4%). Most patients had trauma, 37 had rib fractures (51.4%), Sixty patients (83.3%) underwent thoracic endovascular aortic repair (TEVAR) surgery, eight (11.1%) underwent conservative treatment, and only four (5.6%) underwent open surgery. The overall hospitalization mortality was 12.5%. In multivariate logistic regression, elevated creatinine levels (P = 0.041) and high Glasgow coma scale (GCS) score (P = 0.004) were the predictors of hospital mortality. The median follow-up period was 57 (28–87) months. During the follow-up period, all-cause mortality was 5.6% and no aortic-related deaths were reported. Three patients (4.2%) needed secondary surgery and two of them underwent endovascular repair. Conclusion: Although TEVAR surgery may be associated with intra- or postoperative dissection rupture or serious complications in the treatment of Grade III BTAI, the incidence rate was only 8.9%. Nevertheless, TEVAR surgery remains a safe and feasible approach for the treatment of Grade II or III BTAI, and surgical treatment should be considered first,. A high GCS score and elevated creatinine levels in the emergency department were closely associated with hospital mortality. Younger patients need long-term follow-up after TEVAR. [ABSTRACT FROM AUTHOR]

Topology optimization (TO) provides a systematic approach for obtaining structure design with optimum performance of interest. However, the process requires the numerical evaluation of the objective function and constraints at each iteration, which is computationally expensive, especially for large-scale designs. Deep learning-based models have been developed to accelerate the process either by acting as surrogate models replacing the simulation process, or completely replacing the optimization process. However, most of them require a large set of labelled training data, which is generated mostly through simulations. The data generation time scales rapidly with the design size, decreasing the efficiency of the method itself. Another major issue is the weak generalizability of deep learning models. Most models are trained to work with the design problem similar to that used for data generation and require retraining if the design problem changes. In this work an adaptive, scalable deep learning-based model-order-reduction method is proposed to accelerate large-scale TO process, by utilizing MapNet, a neural network which maps the field of interest from coarse-scale to fine-scale. The proposed method allows for each simulation of the TO process to be performed at a coarser mesh, thereby greatly reducing the total computational time. More importantly, a crucial element, domain fragmentation, is introduced and integrated into the method, which greatly improves the transferability and scalability of the method. It has been demonstrated that the MapNet trained using data from one cantilever beam design with a specific loading condition can be directly applied to other structure design problems with different domain shapes, sizes, boundary and loading conditions. [ABSTRACT FROM AUTHOR]

The tetraruthenium tetrahydrido carbonyl cluster Ru4(µ-H)4(CO)12 (1) reacts with diphenylvinylphosphine under thermal activation to give the substitution products Ru4(µ-H)4(CO)12−n(κ1-Ph2PCH=CH2)n, (2) (n = 3 (a); 4 (b)). Both 2a and 2b have been completely characterized, including by single-crystal X-ray diffraction analysis. Each of the diphenylvinylphosphine ligands in 2a and 2b is terminally bound, via the phosphorus atom, to a different ruthenium metal center, while the hydride positions in the Ru4(µ-H)4 cores retain the D2d symmetry of the parent cluster 1. Clusters 2a and 2b were able to retain their structural integrity at elevated temperatures. Thermolysis of Ru4(μ-H)4(CO)12 (1) in cyclohexane with diphenylvinylphosphine afforded the tri- and tetra-substituted derivatives Ru4(μ-H)4(CO)9(κ1-Ph2PCH=CH2)3 (2a) and Ru4(μ-H)4(CO)8(κ1-Ph2PCH=CH2)4 (2b). For both substituted clusters, the diphenylvinylphosphine ligands are bound terminally to the tetraruthenium core via the phosphorus atoms while the hydride positions retain the D2d symmetry of the parent cluster 1. [ABSTRACT FROM AUTHOR]

The allotrope of carbon, biphenylene, was prepared experimentally recently [Fan et al., Science 372, 852–856 (2021)]. In this Letter, we perform first-principles simulation to understand the bonding nature and structure stability of the possible in-plane heterostructure built by graphene and biphenylene. We found that the graphene–biphenylene in-plane heterostructure only exhibits along the armchair direction, which is connected together by strong covalent bonds and energetically stable. Then, the non-equilibrium molecular dynamics calculations are used to explore the interfacial thermal properties of the graphene/biphenylene heterostructure. It is found that the graphene/biphenylene in-plane heterostructure possesses an excellent interfacial thermal conductance of 2.84 × 109 W·K−1·m−2 at room temperature. Importantly, the interfacial thermal conductance presents different temperature dependence under opposite heat flux direction. This anomalous temperature dependence results in increased thermal rectification ratio with temperature about 40% at 350 K. This work provides comprehensive insight into the graphene–biphenylene heterostructure and suggests a route for designing a thermal rectifier with high efficiency. [ABSTRACT FROM AUTHOR]

Recently, a new two-dimensional allotrope of carbon named biphenylene has been experimentally synthesized. First-principles calculations are preformed to investigate the electronic properties of biphenylene and the doping effect is also considered to tune its electronic, magnetic, and catalytic properties. The metallic nature with an n-type Dirac cone is observed in the biphenylene. The magnetism can be induced by Fe, Cl, Cr, and Mn doping. More importantly, the doping position dependence of hydrogen evolution reaction (HER) performance of biphenylene is addressed, which can be significantly improved by atomic doping. In particular, the barrier for HER of Fe doping case is only âˆ'0.03 eV, denoting its great potential in HER catalysis. [ABSTRACT FROM AUTHOR]

Peat is known as problematic ground with low bearing capacity and extensively high compressibility. Bio-cementation or commonly known as microbial-induced calcite precipitation (MICP) has been recently introduced as a ground improvement alternative for peat under waterlogged condition. Using isolated bacteria strains P19 and P21 from tropical peat, it is found that unconfined compression strength (UCS) increases with bacteria concentration at a reducing rate. A maximum unconfined compressive strength of 82.05 kPa was measured with bacteria strain P21 at 108 CFU/mL. For the range of cementation reagent varying from 0.1 to 4.0 mol/kg, the largest strength improvement occurred at 1 mol/kg and 2 mol/kg using indigenous bacteria and bacteria strain P21, respectively, for peat with sand content of 25%. At 4.0 mol/kg, the cementation reagent has detrimental effect to MICP resulting in significant reduction in strength. Due to MICP, the UCS of peat increases with sand content. Calcium carbonate precipitation results in a reduction of permeability and an increment of strength of peat–sand mixture under a submerged condition up to 28 days. [ABSTRACT FROM AUTHOR]

Recently, the synthesis of biphenylene inspires the substantial attention on the two-dimensional allotrope of carbon. Although elastic, thermal, and electronic properties of biphenylene have been reported, phonon modes and the origin of anisotropy in biphenylene are still unclear. In this work, combining the first-principles calculations and theoretical analysis, we investigate the properties of optical and acoustic phonons in monolayer biphenylene. There are nine Raman-active and five infrared-active modes which can be excited by the Raman or infrared laser. Interestingly, a Raman-active single phonon mode ( A g 3 ) is observed, and its frequency is up to 49.67 THz at the Brillouin zone-center point. This provides promising potential for biphenylene monolayer in the application of phonon lasers, quantum nonlinear elements, and quantum mechanical resonators. Meantime, the Grüneisen constant of an A g 3 mode is up to 2.07 at the zone-center point, suggesting that its Raman spectroscopy can be used to identify the lattice strain and temperature of biphenylene. To explore the origin of anisotropy in biphenylene, we calculate the covalency and cophonicity and find that the inconsistent speed of motion and different intensities of hybridization between these inequivalent carbon atoms should take responsibility for the direction dependent thermal and elastic properties in biphenylene. [ABSTRACT FROM AUTHOR]

2D Janus transition metal dichalcogenide (TMD) semiconductor materials have attracted great interest for their potential applications. Because of the increased requirement for thermal management in 2D devices with single‐atom thickness, a fundamental understanding of interfacial thermal conduction (ITC) has emerging significance. In this work, the ITC of in‐plane heterostructures constructed using MoSSe and WSSe is reported. In addition to the interface connected normally by MoSSe and WSSe with the same type of chalcogen atoms are on the same side of left and right sections, inversional interface by rotation of 180° of WSSe is also considered, in which S atoms are on the opposite side of the left and right sections. Interestingly, the ITC in the normally connected heterostructure is found to be almost twice as much as that in the inversely connected heterostructure. The unusually large change in ITC is attributed to the bending curvature and additional discontinuity in the inversely connected heterostructure. Euler–Bernoulli beam model gives further insight into the origin of such interface bending. The findings offer the very first insight into the phonon transport in Janus heterostructures, and benefit thermal management of 2D devices based on Janus monolayers. [ABSTRACT FROM AUTHOR]

Natural dyes (ND) are gaining increasing interest due to their outstanding merits of being eco-friendly, biodegradable and non-toxic. Wood dyed with extracts from Dalbergia cochinchinensis residues as ND exhibited desirable color appearance and anti-UV property, while the other potential properties of ND dyed wood in terms of water fastness, mildew resistance along with the penetrability of the ND on wood blocks dyeing have not yet been exploited. The present study was aimed at exploring these aspects for multifunction assessment of the ND dyed wood. The results showed that the total color difference (ΔE*: 4.58) and color intensity reduction (PR: 14.01%) of the ND dyed wood declined slightly after washing fastness test in comparison with that of acid red (ΔE*: 32.82; RP: 76.14%) and reactive red (ΔE*: 26.85; RP: 66.52%) dyed wood, which is indicative of its preferable water fastness, which can be ascribed to the hydrophobicity improvement of the wood surface after ND dyeing. In addition, the ND ameliorated the mildew resistance against Aspergillus niger and Trichoderma viride infection. Interestingly, the wood blocks can be completely impregnated with ND under atmospheric pressure dyeing process without any pretreatment and auxiliary. This study provided a promising approach for multifunctional ND dyed wood preparation. [ABSTRACT FROM AUTHOR]

The maintenance of spectral variability between subclass objects and the relationship between hyperspectral (HS) bands have been a fundamental but challenging problem for fusing low spatial resolution (LR) HS and high spatial resolution (HR) multispectral (MS) images. This article presents a locally optimized image segmentation fusion (LOISF) framework for HS super-resolution reconstruction. First, LR HS and HR MS are clustered and segmented, and the label attributes of the segmented objects are identified by the prior information. Then, a novel joint fusion model for different typical ground objects is constructed based on spectral unmixing. The fusion problem is formulated mathematically as a convex optimization of a Frobenius norm, which includes spatial, spectral, and index constraints, with an alternating-directions’ optimization featuring linearization providing the solution. Experimental results demonstrate that the proposed LOISF preserves both spatial details and texture, achieving high spectral fidelity, and yielding significantly improved image quality compared to other state-of-the-art fusion methods. [ABSTRACT FROM AUTHOR]

Rapid development in deep learning methods has brought about wide applications of artificial-neural-network (ANN)-based surrogate models in the field of numerical simulation. Given sufficient training, ANN-based surrogate models can be both accurate and efficient, and thus can be used to replace computationally expensive numerical simulations in problems where intensive numerical simulations are required. However, the training of ANN-based surrogate models relies on a large corpus of ground-truth data that is often generated using full-scale numerical simulations. For such large-scale problems, the computational cost of generating training data can be massive which diminishes the efficiency gained using ANN-based surrogate models and limits their application scope. In this work, a solution scheme is proposed to address this issue by reducing the full-scale numerical simulations needed during training data generation, thus reducing the training cost. The key idea is to utilize a Mapping Network that maps a coarse field to a fine field to generate fine-scale training data. Compared to surrogate models which map parameters/structures to fine fields, Mapping Network is much easier to be trained and thus requires much less fine-scale data. In addition, it has much better transferability and can be easily adopted to a related but different task. Combined with transfer learning, the proposed scheme results in greatly reduced training costs compared to the approach without using Mapping Network. [ABSTRACT FROM AUTHOR]

The separation layer prepared by the conventional coating-crosslinking method is typically thick and prone to forming defective macropores, significantly affecting the water permeability and dye/salt separation performance of membranes. This work presented a novel method to prepare hollow fiber composite membranes for dye/salt separation based on the opposite transmission reaction of crosslinker. In this method, the macromolecule in situ reacted with a small‐molecule crosslinker at the openings of membrane pore channels, forming a separation layer with discontinuous sheet-like and granular structure. Compared to the conventional forward coating-crosslinking method, the separation layer prepared by the opposite transmission reaction method exhibited an ultra-thin thickness of 29.1 nm. Consequently, the composite membrane exhibited a high water permeability of 72.7 L·m−2·h−1·bar−1, which was 2.3 times higher than that of conventional methods. Moreover, the prepared composite membrane presented a more uniformed pore structure, completely retaining the VBB (100%) with a low Na 2 SO 4 rejection of 4.3%, demonstrating excellent dye/salt separation performance. Additionally, the prepared composite membrane exhibited superior anti-fouling properties compared to that prepared by the conventional method. Therefore, the opposite transmission reaction method proposed in this study held promising applications in the preparation of hollow fiber composite membranes for efficient dye/salt separation. [Display omitted] • Opposite transmission reaction of crosslinker was firstly used to prepare dye/salt separation membrane. • The discontinuous distribution of the separation layer resulting from the in-situ reaction was confirmed by EFM. • The optimized membranes had a high water permeability of 72.7 L·m−2·h−1·bar−1. • The optimized membranes exhibited outstanding dye/salt selectivity. • The optimized membranes showed good anti-fouling performance. [ABSTRACT FROM AUTHOR]

Recently, the micromechanical exfoliation method has effectively separated the two-dimensional (2D) SiP 2 flake, which exhibits superior performance in field-effect transistors and photodetectors. In this paper, first-principles calculations were utilized to investigate the phononic properties of a SiP 2 monolayer, which would be significant to explain the thermal deformation of 2D SiP 2 -based devices. We found that the acoustic phonon branches of SiP 2 monolayer demonstrate significant in-plane anisotropy. The anisotropic ratios for the group velocities are 2.41 and 1.66 for the longitudinal and transverse acoustic modes, respectively. Meanwhile, the anisotropic ratio of the negative thermal expansion coefficient only considering the contribution from acoustic phonons is 0.14, while this ratio is ∼0.279 occurs at 120 K when both acoustic and optical phonons are taken into account. For the Raman-active optical phonons, the largest Grüneisen constant of these Raman-active phonons reaches 22.76, while the largest anisotropic ratio of phonon frequency is up to 2.16. To interpret this significant in-plane anisotropy, we calculated the electron density distribution, crystal orbital Hamilton populations (COHP) and interatomic force constants (IFCs), and found the maximal IFC in the x -direction is 5.79 times greater than y -direction, suggesting it as a major origin of the phononic anisotropy. • The significant anisotropic ratios for the thermal expansion constant of SiP 2 monolayer is 0.279 at 120 K. • All the optical phonons are Raman-active with unusual Grüneisen constants. The largest Grüneisen constant is 22.76. • The major origin of in-plane anisotropy is the interatomic force constant with anisotropic ratio of 5.79. [ABSTRACT FROM AUTHOR]

Background: Although interferon regulatory factor 2 (IRF2) was reported to stimulate virus replication by suppressing the type I interferon signaling pathway, because cell cycle arrest was found to promote viral replication, IRF2-regulated replication fork factor (FAM111A and RFC3) might be able to affect ZIKV replication. In this study, we aimed to investigate the function of IRF2, FAM111A and RFC3 to ZIKV replication and underlying mechanism. Methods: siIRF2, siFAM111A, siRFC3 and pIRF2 in ZIKV-infected A549, 2FTGH and U5A cells were used to explore the mechanism of IRF2 to inhibit ZIKV replication. In addition, their expression was analyzed by RT-qPCR and western blots, respectively. Results: In this study, we found IRF2 expression was increased in ZIKV-infected A549 cells and IRF2 inhibited ZIKV replication independent of type I IFN signaling pathway. IRF2 could activate FAM111A expression and then enhanced the host restriction effect of RFC3 to inhibit replication of ZIKV. Conclusions: We speculated the type I interferon signaling pathway might not play a leading role in regulating ZIKV replication in IRF2-silenced cells. We found IRF2 was able to upregulate FAM111A expression and thus enhance the host restriction effect of RFC3 on ZIKV. [ABSTRACT FROM AUTHOR]

With the increase of underground mining depth in coal mines, the distribution of stress fields in deep mining becomes more complex, and the stress localization characteristics are obvious. In order to obtain the local mechanical properties and energy evolution of sandstone, this article is based on the three-point bending experiment and combined with the localized failure theory to explore the evolution law of stress field, deformation field, and energy field of sandstone specimen under tensile stress during the three-point bending experiment. The results show that during the three-point bending test of sandstone, with the increase of the span of the three-point bending test, the peak stress at the characteristic point shows an increasing trend, and the peak stress has obvious regional characteristics. In the vertical direction, the peak stress at the characteristic points in the upper part of the neutral layer is larger, and the peak stress at the characteristic points in the lower part of the neutral layer is smaller. In the horizontal direction, the peak stress at the characteristic points in the near field is higher, and the peak stress at the characteristic points in the middle field and the far field is smaller. The stress field and the deformation field have a good corresponding relationship. The upper far-field peak strain tends to decrease with the increase of the span, and the upper near-field peak strain first decreases and then increases with the increase of the span. The lower near-field peak strain tends to decrease and then increase with increasing span, and the lower far-field peak strain fluctuates with increasing span. The energy field is dependent on the stress field and the deformation field, showing obvious regional characteristics. The energy storage and release capacity of the upper area are higher than those of the lower area. The overall performance of the loading energy storage, rebound energy release, and crack propagation energy release in different areas can be described as far field < mid-field << near field. The near-field energy at different spans presents the characteristics of two stages. When the span is between 140 mm and 150 mm, the near-field energy shows a rapid decreasing trend, and when the span is between 150 mm and 180 mm, the near-field energy presents an obvious increasing trend. [ABSTRACT FROM AUTHOR]

The in vitro antibacterial effect of a synthetic new peptide NJP9-A originated from natural marine invertebrates and its cytotoxicity, selectivity and one possible mechanism of action on human leukemia cells were investigated. NJP9-A showed significant bacteriostasis against Staphylococcus aureus (including methicillin-resistant S. aureus), and had a very low hemolysis efficiency on the human red blood cells. NJP9-A selectively bound to and inhibited the proliferation of leukemia cells, but had almost no inhibitory effect on the proliferation of HEK293 and HUVEC cells. The underlying mechanism of NJP9-A's anti-leukemia cell effect may involve changing the expression of PIK3R1 (PI3K p85 regulatory subunit 1), and the corresponding PI3K signal transduction pathway. NJP9-A inhibits Gram-positive bacteria and is cytotoxic to leukemia cells. The underlying mechanism of NJP9-A's anti-leukemia cell effect is still unclear, but it may be related to the alteration of PIK3R1 expression. [ABSTRACT FROM AUTHOR]

Possessing long-range FM order and tunable interlayer magnetic coupling, extensive investigations of monolayered ferromagnetic chromium triiodide (CrI3) have been developed. In this work, by means of first-principles simulation, we systematically calculated the electronic and magnetic characteristic of two-dimensional (2D) CrI3 adsorbed by gas molecules, CO, H2, H2O and N2, which can provide theoretical guidance to modulate the desired properties of this layered material. The results show that the adsorption of those gas molecules can significantly enhance FM couplings of monolayer CrI3. In particular, the N2 adsorption can remarkably improve the Curie temperatures of the pristine CrI3 monolayer by about 2.6 times. We also hope that our findings can provide more interest around the recently studied 2D FM semiconductors. [ABSTRACT FROM AUTHOR]

In all kinds of traffic accidents, the unconscious departure of the vehicle from the lane is one of the most important reasons leading to the occurrence of these accidents. In view of the specific problem of lane departure, a lane departure decision-making method is established without calibration relying on the Kalman filtering fuzzy logic algorithm, according to the characteristics of expressway lanes, based on the machine vision and hearing fusion analysis of lane departure, integrating the extraction of the linear lane line model and the region of interest (ROI) in this paper to judge the degree of vehicle departure from the lane by integrating the slope values of the 2 lane lines in the road image. The results show that the system has good lane recognition capabilities and accurate departure decision-making capabilities, and meet the lane departure warning requirements in the expressway environment. [ABSTRACT FROM AUTHOR]

A fast back-projection (FBP) imaging algorithm is proposed to generate 3-D uniformly balanced images of an object embedded in a layered structure based on a combined near-field monostatic and bistatic synthetic aperture radar (SAR) system. The spectral layered Green’s function is used in the FBP algorithm. Like conventional real-time imaging algorithms, the complexity of the imaging function is reduced via the stationary phase method, and the fast Fourier transform is implemented to accelerate the computation. Unlike conventional real-time imaging algorithms, the singularity problem associated with Green’s function and antenna pattern is solved in this proposed algorithm by using a point spread function (PSF). For a real-time imaging system, besides fast image generation, an efficient data acquisition is needed. A combined monostatic and bistatic SAR configuration is used here to decrease the data collection time. The performance of this proposed FBP method is demonstrated by measurements of a stratified environment. [ABSTRACT FROM AUTHOR]

In this article, when the cascaded H-bridge topology is used in the asymmetrical multilevel hybrid energy storage system (AM-HESS), the asymmetry of the energy storage components’ types and voltages makes it difficult for traditional modulation methods to realize an independent power control of each energy storage unit. Thus, these methods cannot be directly applied to the realization of the complex working modes of AM-HESS. To this end, an AM-HESS hybrid level shifted pulsewidth modulation (PWM) (HLS-PWM) technique is proposed. According to the directions of supercapacities’ (SCs’) output power and the total output power of the energy storage system, the HLS-PWM is divided into the two fundamental modes—the same (MP) and opposite (MN) modes. Subsequently, the SC charge and discharge control under both the unit power factor and the nonunit power factor is analyzed for the two modes. Furthermore, five operation modes and the power control method of AM-HESS are implemented through the charge and discharge control of the SC. Finally, simulation and experimental results verify that the proposed HLS-PWM can realize an efficient power control of the AM-HESS. [ABSTRACT FROM AUTHOR]

This work investigates interfacial thermal transport in phononic‐mismatched heterostructures that consists of pristine black phosphorene and its phononic crystal. It is found that the presence of the sub‐periodic structure results in reduced thermal conductivity in phononic crystals. As opposed to intuitive expectations, a slight temperature jump is observed at the interface of nanophononic heterostructures, which is only about 10% of that at conventional interfaces consisting of dissimilar materials. Consequently, contact thermal conductance in the nanophononic heterostructure is 10−30 times higher than that of mass‐mismatched interfaces in a comparative study. Moreover, in contrast to conventional heterostructures achieved by interfacing dissimilar materials, weak temperature dependence is observed in interfacial thermal conductance, and thermal rectification is sharply suppressed. These phenomena are well explained based on lattice dynamic insights. This work not only enhances the understanding of the fundamental physics of phonons transport across interface, but also facilitates the possible spectrum of application ranges from thermoelectrics, thermal management, to thermal cloak. [ABSTRACT FROM AUTHOR]

Flow state can be changed by multiple disturbances and uncertain factors in a complex flow environment, which calls for great interest to adjust the control law automatically to adapt to the changing flow environment. Model-based control can obtain predetermined control effects, but its adaptive ability is limited due to the modeling accuracy and unmodeled dynamics of the reduced-order model. To overcome these limitations, the data-driven adaptive control of transonic buffet flow based on the radial basis function neural network (RBF-NN) is carried out in this work. The actuator is the trailing edge flap, and the feedback signal is the lift coefficient. The historical input and output are used in the RBF-NN adaptive control to calculate the current control input from the neural network. When the flow state changes, the parameters of the neural network are adjusted by an adaptive mechanism to make the system work in an optimal or a near-optimal state automatically. Results show that buffet loads can be suppressed completely by RBF-NN control, even if the freestream Mach number and the angle of attack change continuously [from (M, α) = (0.7, 5.5°) to (M, α) = (0.8, 1.5°)]. The control strategy proposed in this work only needs the historical response data of the flow field, and it shows little dependence on the low-order linear model of the system. Therefore, it can be applied to the unstable flow control, in which the low-order model of the flow is difficult to construct and automatically adapt to the changing flow environment. [ABSTRACT FROM AUTHOR]

As a pre-clinical assessment, the present study aimed to investigate the safety and effectiveness of a novel valved pulmonary arterial conduit constructed entirely from biomaterials by transplanting it in the outflow tract of the right ventricle in sheep. Under extracorporeal circulation, the valved pulmonary arterial conduit was used to replace the pulmonary artery of sheep with a beating heart. The performance was assessed at 30, 90 and 180 days post-surgery. Hemodynamic and structural changes were evaluated, and safety was assessed after 180 postoperative days. The hemodynamic effect and biosafety of the implant were further evaluated by observing the changes in various pressure indicators of the heart, echocardiographic results, anatomical and pathological examination results, liver and kidney functions, routine blood tests, a blood coagulation test, and other test results following implantation of the purely biotic valved conduit. The conduit was successfully implanted in 12 sheep and no mortality occurred postoperatively. During the 180-day follow-up, there was no obvious stenosis or regurgitation of the right ventricular outflow tract and pulmonary valve after valved conduit implantation. The findings of autopsy, pathology and laboratory examinations were unremarkable. The implantation of this biosynthetic vascular graft into animals meets the safety and effectiveness requirements for clinical application. This pulmonary arterial conduit has potential clinical application for children with complex congenital heart disease who require pulmonary artery reconstruction to achieve a radical cure. [ABSTRACT FROM AUTHOR]

We present a systematic method for designing dual-polarized, platform-mounted, high-frequency (HF) antennas for near vertical incidence skywave (NVIS) applications. To overcome the bandwidth (BW) and efficiency limitations of electrically small antennas, the characteristic mode (CM) theory is used to exploit the metallic platform as the main radiator. Low-profile coupling elements are mounted on different locations of the platform to excite two orthogonal, horizontally polarized CMs. This way, dual-polarized operation is achieved with a high isolation and sufficiently wide BW. In the design process, several key practical issues are taken into account and their impacts on the performance of the antenna are examined carefully. These include the type and design of the coupling elements, the presence and type of the earth, and the non-idealities and power handling capability in the impedance matching network components. The simulation results of both a full-scale and a 1:50 scaled model of the proposed structure are presented. The scaled-model prototype was fabricated and characterized in the presence of a ground plane emulating the properties of real earth at the scaled frequency of operation. The measurement results show a good agreement with the simulations, demonstrating the efficacy of the proposed approach in designing dual-polarized, platform-based HF antennas. [ABSTRACT FROM AUTHOR]

Purpose: The face-centered cubic structured single-phase FeCoNiCrMn high-entropy alloys (HEAs) were prepared to study the friction and wear behavior of HEAs under MoS2-oil lubrication. Design/methodology/approach: FeCoNiCrMn alloys were subjected to ball-on-disc reciprocating sliding against the GCr15 ball. L25(56) orthogonal wear tests were designed for velocity Vrel (4.167-20.833 mm/s), load FN (10-50 N), temperature T (RT-140 °C) and time t (5-20 min). Based on orthogonal test results, multivariate repeated measures ANOVA was performed, and further comparative experiments were conducted for Vrel, FN and T. Energy dispersive spectrometer and scanning electron microscope were applied to characterize the surface morphology of wear scar and its element distribution. Findings: Vrel, FN and t exerted the most significant influence (p < 0.01) on the average friction coefficient f. Vrel and FN were identified as the momentous effect (p < 0.01) on wear volume ΔV. T (≥50 °C) had positive correlation with f and ΔV, and both Vrel and FN correlated negatively with f. The dominant abrasive wear was attributed to the large hardness difference of the friction pair. Fatigue wear and delamination wear were experienced at higher speeds (Vrel ≥ 12.5 mm/s) and loading levels (FN ≥ 40 N). Elevated temperature weakens the lubrication effect of MoS2-oil and the mechanical properties of FeCoNiCrMn matrix, intensifying abrasive wear. Originality/value: This study is expected to provide references for exploration on the wear behavior of single-phase HEAs under complex working conditions with lubrication and hence will help develop the application of HEAs in practical engineering. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0303 [ABSTRACT FROM AUTHOR]

Due to their designable properties, microstructural materials have emerged as an important class of materials that have the potential for used in a variety of applications. The design of such materials is challenged by the multifunctionality requirements and various constraints stemmed from manufacturing limitations and other practical considerations. Traditional design methods such as those based on topological optimization techniques rely heavily on high-dimensional physical simulations and can be inefficient. In addition, it is difficult to impose geometrical constraints in those methods. In this work, we propose a deep learning model based on deep convolutional generative adversarial network (DCGAN) and convolutional neural network (CNN) for the design of microstructural materials. The DCGAN is used to generate design candidates that satisfy geometrical constraints and the CNN is used as a surrogate model to link the microstructure to its properties. Once trained, the two networks are combined to form the design network which is utilized to for the inverse design. The advantages of the method include its high efficiency and the simplicity in handling geometrical constraints. In addition, no high-dimensional sensitivity simulations are required. The performance of the method is demonstrated on the design of microstructural materials with desired compliance tensor, subject to specified geometrical constraints. [ABSTRACT FROM AUTHOR]

Polysemic acronyms are very common in the field of biomedicine. These acronyms have different senses in different contexts. The ambiguity of acronyms may cause significant negative impact on the understanding of the full text by machine learning. To address the disambiguation of acronyms in the biomedical domain, most associated studies are based on methods using word-level contextual features. These methods require abundant relevant external resources for model training, and the accuracy of their disambiguation of acronyms may decrease greatly upon the lack of external resources. In this study, disambiguation of biomedical acronyms was investigated on the basis of the character-level feature model to realize the disambiguation of biomedical acronyms with largely limited external corpora. First, sentences containing ambiguous acronyms were extracted through retrieval and the feature vector of the context were initialized by using the character-level features. Second, these initial vectors were input into the bidirectional long shortterm memory neutral network model for training. Finally, the disambiguation of acronyms was realized by the outputs of the neutral network model through the Softmax classification approach. The results of acronym disambiguation based on character-level feature model were also compared with those based on word-level feature models. Results demonstrate that the average accuracy of the character-level feature neutral network algorithm reaches 85.82% on the dataset of 106 common biomedical acronyms. Thus, the character-level feature neutral network algorithm is superior to the traditional methods, which use a large number of external resources. This study confirms that the disambiguation method based on character-level features is applicable to the disambiguation of biomedical acronyms under limited relevant data. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, we systematically investigate the electronic and optical properties of van der Waals (vdW) heterostructures composed of graphene-like gallium nitride (g-GaN) and transition metal dichalcogenides (TMDs). The investigated vdW heterostructures (g-GaN/MoS 2 , g-GaN/WS 2 , g-GaN/MoSe 2 , and g-GaN/WSe 2) are all semiconductors with direct bandgap. In particular, both the g-GaN/MoS 2 and g-GaN/WS 2 vdW heterostructures possess type-II band alignment, which will facilitate the separation of photogenerated carriers, and enhance their lifetime. Furthermore, band edge positions of these two heterostructures satisfied both water oxidation and reduction energy requirements, suggesting the potential in photocatalysts for water splitting. In addition, both g-GaN/MoS 2 and g-GaN/WS 2 vdW heterostructures exhibit a high electron mobility, which ensure that the redox reactions for water splitting will be effectively proceeded. More importantly, they show significant absorption peaks in the visible light region, leading to highly efficient utilization of the solar energy. These fascinating properties render the g-GaN/MoS 2 and g-GaN/WS 2 vdW heterostructures high-efficiency photocatalysts for water splitting. Unlabelled Image • Many g-GaN/TMD vdW heterostructures are direct-bandgap semiconductors. • Both g-GaN/MoS 2 and g-GaN/WS 2 form type-II heterostructure. • g-GaN/MoS 2 and g-GaN/WS 2 satisfy both water oxidation and reduction potential levels. • Both g-GaN/MoSe 2 and g-GaN/WSe 2 vdW heterostructures have type-I band alignment. [ABSTRACT FROM AUTHOR]

• (3-Aminopropyl) triethoxysilane with 1,4-Butane sultone to obtain zwitterionic silane (ZSi). • ZSi is grafted onto nano-hydroxyapatite (nHA) to obtain nHA-ZSi. • nHA-ZSi reduces the crystallization of the polymer matrix due to filler effect. • The specific capacitance increases with the addition of nHA-ZSi; reaches the maximum at 20%. In this study, we intend studying the role of nano-hydroxyapatite bearing zwitterion within carboxylated chitosan hydrogel electrolyte in improving supercapacitor performance. First, we carry out the ring-opening addition of (3-Aminopropyl) triethoxysilane with 1,4-Butane sultone to obtain zwitterionic silane (ZSi). Then, ZSi is grafted onto nano-hydroxyapatite (nHA) by condensation process to obtain nano-hydroxyapatite grafted zwitterionic silane (nHA-ZSi). The successful synthesis of nHA-ZSi is confirmed by Fourier transform infrared spectroscopy and 13C Nuclear magnetic resonance. Differential scanning calorimetry shows that the incorporation of nHA-ZSi reduces the crystallization of the polymer matrix due to filler effect. Afterwards, nHA-ZSi with 5%, 10%, 20%, 30% are mixed with carboxylated chitosan (CCS) to obtain composite films (CCS/nHA-ZSi). The stress-strain curves of CCS/nHA-ZSi are characterized by tensile testing. Ionic conductivities of hydrogel electrolytes are estimated by soaking CCS/nHA-ZSi in 1 M Na 2 SO 4 via electrochemical impedance. Furthermore, CCS/nHA-ZSi hydrogel electrolytes are assembled with symmetric carbon electrode for electrochemical tests, including cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance. The specific capacitance increases with the addition of nHA-ZSi; reaches the maximum at 20%; and then decreases due to aggregation. After 5000 cycles, CCS/20% nHA-ZSi supercapacitor has 98% capacitance retention at 6 mA/cm2. This study demonstrates that nano-hydroxyapatite bearing zwitterion is a beneficial additive for both mechanical strength and ionic conductivity in hydrogel electrolytes. [Display omitted] [ABSTRACT FROM AUTHOR]

33928950 5 Wang K., He J., Zhang M., Wang H., Zhang G. Magnon-phonon interaction in antiferromagnetic two-dimensional MXenes. 26722716 3 Webster L., Liang L., Yan J.-A. Distinct spin-lattice and spin-phonon interactions in monolayer magnetic CrI3. In contrast to acoustic phonons, optical phonon modes can be used to evaluate interlayer coupling, spin-orbit coupling, magneto-optic coupling, and the number of atomic layers through Raman spectroscopy measurement. [Extracted from the article]

Graphical abstract Highlights • The most stable structures of the vertical heterostructures of MX 2 /BP (M =Mo, W; X =S, Se) are obtained. • Van der Waals interaction are found in these heterostructures. • Type-II band alignment are addressed in MoSe 2 /BP and WSe 2 /BP which can separate the photogenerated-charge. • All these heterostructures have excellent ability of optical absorption in the near-infrared and visible regions. Abstract Van der Waals (vdW) heterostructure can improve the performance of the 2D materials and provide more applications. Based on density functional theory (DFT) calculations, the properties of vertical heterostructures formed by transition metal dichalcogenides (TMDs) MX 2 (M = Mo, W; X = S, Se) and boron nitride (BP) were addressed. In particular, the vdW interaction exist in all these heterostructures instead of covalent bonding. The MoSe 2 /BP and WSe 2 /BP vdW heterostructures possess direct bandgap characterized by type-II band alignment and powerful built-in electric field across the interface, which can effectively separate the photogenerated-charge. Meanwhile, the MoS 2 /BP and WS 2 /BP vdW heterostructures also have the direct bandgap and intrinsic type-I band alignment. Furthermore, all heterostructures exhibit excellent optical absorption in the visible and near-infrared regions. Our investigation shows an effective method to design new vdW heterostructures based on TMDs and explores their applications for photocatalytic, photovoltaic, and optical devices. [ABSTRACT FROM AUTHOR]

Abstract Four vertical heterostructures based on two-dimensional transition-metal dichalcogenides (TMDs) – MoS 2 /GeC, MoSe 2 /GeC, WS 2 /GeC, and WSe 2 /GeC, were studied by density functional theory calculations to investigate their structure, electronic characteristics, principle of photogenerated electron–hole separation, and optical-absorption capability. The optimized heterostructures were formed by van der Waals (vdW) forces and without covalent bonding. Their most stable geometric configurations and band structures display type-II band alignment, which allows them to spontaneously separate photogenerated electrons and holes. The charge difference and built-in electric field across the interface of these vdW heterostructures also contribute to preventing the photogenerated electron–hole recombination. Finally, the high optical absorption of the four TMD-based vdW heterostructures in the visible and near-infrared regions indicates their suitability for photocatalytic, photovoltaic, and optical devices. Highlights • The most stable structures of the vertical heterostructures of TMDs/GeC are obtained. • Van der Waals interaction are found in these heterostructures. • Type-II band alignment are addressed in all the vdW heterostructures which can separate the photogenerated-charge. • All the structures are suitable for photocatalytic, photovoltaic, and optical devices. • All the structures show high optical absorption in the visible and NIR ranges. [ABSTRACT FROM AUTHOR]

In previous studies, Gentianella acuta (Michx.) Hulten was reported to contain xanthones, iridoids, terpenoids, and sterols and is mainly used to cure hepatitis, jaundice, fever, headache, and angina pectoris. In this study, we used bioassay guided fractionation to identify compounds from G. acuta and investigated their activity against hydrogen peroxide (H2O2)-induced apoptosis of H9c2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic (GCLC) expression were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was evaluated using western blot. The results showed that all four compounds had protective effects on H9c2 cells. The transcription levels of HO-1 and GCLC significantly increased in H9c2 cells pretreated with norswertianolin (1), swetrianolin (2), demethylbellidifolin (3), and bellidifolin (4). However, compared to the model group, the transcription levels of Nrf2 were not enhanced by pretreatment with compounds 1, 2, and 4. The protein expression levels of HO-1 and GCLC in H9c2 cells were greater than that in the H2O2-treated group, and the expression of Nrf2 was not significantly changed except by swetrianolin treatment; inhibitors can reverse the protective effect by ZnPP (15 μM), BSO (10 μM), and brusatol (10 μM). The results indicated that the four compounds isolated from G. acuta inhibited the oxidative injury induced by H2O2 by activating the Nrf2/ARE pathway in H9c2 cells and provide evidence that G. acuta may be a potential therapeutic agent for the treatment of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Unsteady separated flow is a common flow condition causing many detrimental effects in aerospace and other fields. Open-loop control is a potential means to eliminate these drawbacks. At present, the unsatisfactory performance of open-loop control mainly attributes to the high-dimensional parameter optimization procedure and the lack of efficient knowledge-guided control law design methods. This paper proposes a method managing to directly obtain the anti-resonant frequency from the input and output amplitude-frequency characteristic curves of the reduced-order model of the flow-control coupled system. Simultaneously, a negative gain criterion is proposed to judge whether the target control effect can be achieved under the current parameter combination. For the control of low Reynolds number flow around a cylinder, the simulation results show that the optimal open-loop control frequency is 1.268 times the natural frequency of the flow, which is consistent with the anti-resonant frequency, and 26.8% of the lift fluctuation is suppressed. This paper also studies the influence of parameters such as flow frequency change, control start time, jet mass flow rate, and so on. Furthermore, control position is the key parameter affecting the amplitude-frequency characteristics. The anti-resonance points on the curves corresponding to different control positions can also guide the design of the optimal control frequency, and the negative gain criterion is still applicable. This method greatly reduces the time consumption in parameter optimization and improves the engineering application prospect of the open-loop control in unsteady separated flow control. [ABSTRACT FROM AUTHOR]

The uniform diffraction tomographic (UDT) algorithm corrects discontinuities associated with conventional DT algorithms when applied to imaging of objects buried in layered media. The cause of the discontinuities in DT is in the implementation of the stationary phase solution for evaluating the spectral integral. The usual approach is to make a far-field approximation assuming that the depth is large. However, this is not appropriate for near-field imaging. UDT overcomes this issue by choosing the correct large asymptotic parameter in the exponent of the spectral integrand. In this paper, the original 2-D scalar UDT algorithm is extended to a fully vector 3-D solution involving the dyadic Green’s function for the layered media, the polarization of the gain pattern of the probe antenna, and the stationary phase evaluation of a 2-D spectral integral. The 3-D UDT is demonstrated to provide smoothly continuous images, and like the conventional DT, the fast Fourier transform is implemented to generate images in real time. 3-D numerical simulations and experimental results are presented to verify the accuracy and efficacy of the 3-D UDT algorithm. [ABSTRACT FROM AUTHOR]

In this study, we propose a fluorescent bilayer hydrogel soft actuator that responds quickly to multiple environmental stimuli. The two layers of hydrogel contain poly(N-isopropylacrylamide) and poly(2-(dimethylamino) ethyl methacrylate), respectively, which enable their mechanical response to temperature and pH. Additionally, both hydrogel layers contain poly(ethylene oxide) diacrylate, which serves as the crosslinker. Thanks to the anisotropic swelling of two layers, the bilayer hydrogel structure exhibits rapid, reversible, and repeatable bending motion, under varying temperature or pH. In addition, a photo-sensitive coumarin-based unit is introduced into the hydrogel network to add fluorescence. A four-arm gripper made of hydrogel bilayers demonstrates rapid actuation in response to both temperature and pH. Furthermore, we design a circuit switch using the hydrogel bilayer to serve as one “bidirectional alarm” and selectively turn on light emitting diodes in different media. This work demonstrates the applications of the hydrogel bilayer as a soft actuator and a circuit switch in ionic circuitry, enabling potential applications in a wide range of fields, including biomimetic devices, biocompatible/medical devices, and environmental sensors. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) based nanomaterials have great potential in a wide range of biomedical areas, including bioimaging, biosensor, and tissue engineering. Thus, it is highly desired to develop novel cost‐effective, eco‐friendly and easy to scale‐up fabrication for CDs based nanomaterials for biomedical applications. Herein, we developed a facile synthesis of CDs by a one‐step hydrothermal method. The synthesized CDs showed stable photoluminescence, high‐resolution imaging of live cells and low cytotoxicity. Furthermore, the CDs were prepared to electrospun nanofiber mats (CDs‐NFMs), where enough carboxylic acid moieties and hydroxyls on the surface of the nanofibers, leading to excellent biocompatibility and fluorescence property. More importantly, cell proliferation on the CDs‐NFMs was much better than that on NFMs without CDs; moreover, CDs‐NFMs could also guide cells growth along the nanofibers and enhance the cellular activities, which indicated that the functional groups on the surface of the CDs play a critical role in supporting cellular activities. Combining with excellent fluorescence property, we anticipate that this finding greatly enhances great potential applications of CDs for cell culture, tissue engineering as well as other biomedical applications. POLYM. COMPOS., 39:73–80, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Persimmon ( Diospyros kaki L.) leaves are extensively used in Chinese medicine and are also excellent source of dietary polyphenols. Here we investigated the antiproliferative and pro-apoptotic activity of the total flavonoids extracted from persimmon leaves (FPL) in PC-3 cells. After treating cells with different concentration of FPL, Quercetin or Rutin for 24 h, MTT and flow cytometry were used to measure the cytotoxicity, apoptotic rate and cell cycle arrest. Compared with Quercetin and Rutin, FPL showed higher cytotoxicity at 12.5 and 25 μg/ml concentrations and also presented lower IC 50 in PC-3 cells. In addition, FPL induced PC-3 cells apoptosis by activation of oxidative stress, as detected by ROS, MDA, nitrite and iNOS activity, and increased mitochondrial membrane permeability. Morphological changes, inactivation of Bcl-2, upregulation of BAX, release of cytochrome c and activation of downstream apoptotic signaling in FPL-treated PC-3 cells also suggested apoptotic death. Meanwhile, FPL significantly inhibited migration of PC-3 cells. Therefore, FPL inhibited proliferation, migration and induced apoptosis of PC-3 cells by activation of oxidative stress and mitochondrial-related apoptosis. [ABSTRACT FROM AUTHOR]

This work studied the anti-penetration performance and energy absorption characteristics of the honeycomb aluminum core structure. Tests of penetrating depth were conducted. The response and deformation resistance of the aluminum sandwich structure with a regular hexagonal honeycomb were studied through numerical simulation. The effect of the face/back plate thickness ratio and the shape of the core layer unit on the performance of the aluminum sandwich structure with a regular hexagonal honeycomb were compared and analyzed with a theoretical model of equivalent target calculation. Based on the results, the aluminum sandwich structure with a regular hexagonal honeycomb has the strongest anti-penetration capability when the thickness ratio of the face/back plate is set to 2.5:1. In terms of the energy consumption, the Arrow and concave hexagonal honeycomb aluminum sandwich structures are 14.7% and 25.9%, respectively, than the aluminum sandwich structure with a regular hexagonal honeycomb. The typical hierarchical honeycomb aluminum sandwich structure has better energy absorption characteristics than the aluminum sandwich structure with a regular hexagonal honeycomb. Therefore, the anti-penetration performance of the honeycomb aluminum sandwich structure can be improved by adjusting the thickness ratio of the face/back plate and changing the shape of the core layer. The research results are of great significance in guiding the design of the honeycomb aluminum sandwich structure. [ABSTRACT FROM AUTHOR]