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Abstract: Diurnal evolution of the barrier layer (BL) and its local feedback features in the central Taiwan Strait (119.2°E, 24.3°N) during summertime monsoon are investigated using in situ moored observations conducted by the “Yan-Ping 2” research vessel in late June 2005. During the initiation phase, for the non-solar radiation tends to be trapped in the upper mixed layer, whereas the solar radiation can penetrate deeply through the mixed layer approaching the thermocline, most heat is accumulated inside the BL inducing an inverse-thermal layer. Along with heat convergence inside the BL, thermal exchange increases between the BL and the overlaying mixed layer and finally, a prominently warming mixed layer is formed. Moreover, the BL is associated with a buoyancy frequency minimum with mild stability. Further analysis reveals that the BL’s local feedbacks can be divided into two aspects, on one hand, the BL can generate dramatic changes in the local sensible and latent heat fluxes; on the other hand, the sub-halocline and the thermocline serve as two interfaces during the downward transmission of the wind stirring turbulent kinetic energy (TKE) and as a result, most TKE is retarded by the shallow halocline and being trapped above the upper mixed layer, while the residual pierced through the base of the mixed layer is likewise blocked by the thermocline.

• Martensitic substructure is tailored mainly by flat and straight low-index lamellar boundaries, and is intrinsically thermally stable. Structural coarsening was realized by the migration of terminal tips, and more terminal tips decrease the tempering resistance. In this paper, low- and high-strength lath martensite (350 and 640 HV) was fabricated in an IF steel via high pressure martensitic transformation. The microstructure and the softening during their tempering from 200 °C to 800 °C for 1 h were systematically investigated. A carbon-irrelevant tempering process was proposed, exhibiting a three-stage structural evolution pattern depending upon the tempering degree (1-(HV-HV FP)/(HV NP -HV FP), where the HV is the instant hardness, HV NP is the non-tempered hardness and HV FP is the fully tempered hardness): (1) low tempered (<10%), removing the loose dislocations and dislocation boundaries within martensitic variants; (2) medium tempered (10%-50%), eliminating the martensitic variant laths via the migration of their terminal tips; (3) highly tempered (>50%), clearing up the remained variant laths via the migration of the triple junctions. Martensite-type microstructure is tailored by low-index lamellar variant boundaries and is thus intrinsically thermally stable, whereas the mobile terminal tips decrease the tempering resistance. The underlying mechanism for such carbon-irrelevant process was discussed and the potential effect on the tempering behavior of carbon-contained martensite was highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

The three-stream radiation transfer model is used to investigate the fluctuation in the underwater diffuse attenuation coefficient of downwelling irradiance in the polar ocean with a high solar zenith angle and different direct radiation proportions. First, the applicability of the three-stream radiation model in the polar region is validated by using 18 in situobservation data from September to October 2009 in the Beaufort Sea. Statistics show that in the absence of sea ice, the average relative errors between the simulation and observation values for 490 nm downwelling irradiance (Ed(490)) and its diffuse attenuation coefficient (Kd(490)) are 7.04% and 9.88%, respectively. At the stations surrounded by sea ice, the radiation is relatively small due to ice blocking, and the average relative errors simulated by the model reach 15.89% and 15.55%, respectively. Second, simulations with different chlorophyll concentrations and different proportions of direct radiation reveal that a high solar zenith angle has a greater impact on Kd(490) in the surface water. Kd(490) is less affected by the light field (affected by the solar zenith angle and the proportion of direct radiation) at depths greater than 30 m, and meets the linear relationship with the inherent optical parameters (the sum of the absorption coefficient and backscattering coefficient). The surface Kd(490) is still consistent with that at a depth of more than 50 meters under a high solar zenith angle, implying that the surface Kd(490) can also be considered as an inherent optical parameter at a high solar zenith angle (greater than 60 degrees). The relative error of obtaining surface Kd(490) by using the linear relationship at the 50 m layer is found to be less than 8% in the seawater with chlorophyll concentration greater than 0.05 mg m−3. The effect of the solar zenith angle and proportion of direct radiation can be ignored when measuring the diffuse attenuation coefficient in the polar region. Finally, the model can correct the ice induced fluctuation in downward irradiance, allowing for optical research of seawater beneath the ice in the polar ocean.

For solving the dilemma of the short exothermic life-span of WO3based metastable interstitial composites (MICs) with extensive application prospect, this paper has firstly designed the promising anti-wetting Al/WO3MICs via electrophoresis assembly of nano-Al and WO3particles fabricated by hydrothermal synthesis method, followed by the subsequent fluorination treatment. A combination of X ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR) techniques were utilized in order to characterize the crystal structure, microstructure, and elemental composition distribution of target films after different natural exposure tests. The product with uniform distribution and high purity possesses a high contact angle of ∼170° and a minute sliding angle of ∼1°, and displays the outstanding anti-wetting property using droplets with different surface tensions. It also shows great moisture stability in high relative-humidity circumstances after one year of the natural exposure experiment. Notably, the heat output of a fresh sample can reach up to 2.3 kJ/g and retain 96% after the whole exposure test, showing outstanding thermo-stability for at least one year. This work further proposed the mechanism of anti-wetting Al/WO3MICs considering the variation tendency of their DSC curve, providing a valuable theoretical reference for designing other self-protected MICs with a long exothermic life-span applied in wide fields of national defense, military industry, etc.

Objectives: In this study, we explored how adiponectin mediated urotensin II (UII)-induced tumor necrosis factor-α (TNF-α) and α-smooth muscle actin (α-SMA) expression and ensuing intracellular signaling pathways in adventitial fibroblasts (AFs). Methods: Growth-arrested AFs and rat tunica adventitia of vessels were incubated with UII and inhibitors of signal transduction pathways for 1–24 h. The cells were then harvested for TNF-α receptor (TNF-α-R) messenger RNA (mRNA) and TNF-α protein expression determination by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Adiponectin and adiponectin receptor (adipoR) expression was measured by RT-PCR, quantitative real-time PCR (qPCR), immunohistochemical analysis, and cell counting kit-8 (CCK-8) cell proliferation experiments. We then quantified TNF-α and α-SMA mRNA and protein expression levels by qPCR and immunofluorescence (IF) staining. RNA interference (RNAi) was used to explore the function of the adipoR genes. To investigate the signaling pathway, we applied western blotting (WB) to examine phosphorylation of adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK). In vivo, an adiponectin (APN)-knockout (APN-KO) mouse model mimicking adventitial inflammation was generated to measure TNF-α and α-SMA expression by application of qPCR and IF, with the goal of gaining a comprehensive atlas of adiponectin in vascular remodeling. Results: In both cells and tissues, UII promoted TNF-α protein and TNF-α-R secretion in a dose- and time-dependent manner via Rho/protein kinase C (PKC) pathway. We detected marked expression of adipoR1, T-cadherin, and calreticulin as well as a moderate presence of adipoR2 in AFs, while no adiponectin was observed. Globular adiponectin (gAd) fostered the growth of AFs, and acted in concert with UII to induce α-SMA and TNF-α through the adipoR1/T-cadherin/calreticulin/AMPK pathway. In AFs, gAd and UII synergistically induced AMPK phosphorylation. In the adventitial inflammation model, APNdeficiency up-regulated the expression of α-SMA, UII receptor (UT), and UII while inhibiting TNF-α expression. Conclusions: From the results of our study, we can speculate that UII induces TNF-α protein and TNF-α-R secretion in AFs and rat tunica adventitia of vessels via the Rho and PKC signal transduction pathways. Thus, it is plausible that adiponectin is a major player in adventitial progression and could serve as a novel therapeutic target for cardiovascular disease administration.

Reconfigurable metamaterials with specific deformation modes show great promise in applications such as multifunctional antenna, stretchable electronic device, and reconfigurable soft robot, due to their ability to achieve multiple operational states within a single system. Previous researches on active metamaterials with bending deformation responses revealed two main issues: (1) achieving reconfigurable deformation within the same metamaterial is challenging due to the reliance on uniform external field actuation; and (2) there is a lack of in-depth studies on the microstructure-property relationships for the bending deformation responses of network metamaterials due to the lack of theoretical analysis. To address these issues, this study presents a mechanical design strategy for an electrothermally actuated network metamaterials to realize reconfigurable bending deformation. A theoretical model describing the electrothermally actuated bending deformation responses is developed through a three-level analysis, which offers a comprehensive understanding of the parameter-property relationships and accurately describes the bending deformation behaviors. The validity of these mechanical models is confirmed through finite element analyses (FEAs) and experimental results. These mechanical models provide analytical solutions for crucial mechanical quantities, including the electrothermally actuated bending angles and effective strains for bending deformation responses. The bending behaviors of the reconfigurable metamaterials under electrothermal actuation can be adjusted by the key nondimensional geometric parameters and the actuation strategies. Additionally, experimental results and FE calculations demonstrate that multiple bending responses can be realized within a single metamaterial by different actuation strategies. This study offers comprehensive guideline from theoretical predictions, FE calculations, and experimental demonstrations for future researched of reconfigurable metamaterials to realize required deformation behaviors.

Laser-induced graphene (LIG) represents a fast-speed and low-cost method to prepare the customizable graphene-based patterns in complex configurations with exceptional electrical performance. This paper presents the applications of LIG formed on the commercial polyimide (PI) film as the stretchable strain sensor and electrical-actuated actuators. First, the conductive performances of the LIG were systematically revealed under different fabrication conditions via investigating the effects of processing parameters, and the fluence of the laser was experimentally demonstrated as the only crucial parameter to evaluate the LIG formation, facilitating the selection of optimized manufacturing parameters to prepare the LIG with desired electrical performances. Then, the LIG-based strain sensor which can undergo over 50% tensile strain was fabricated by transfer of the LIG from the PI film to polydimethylsiloxane. The variety of LIG-based electro-thermal actuators to achieve pre-designed 3D architectures was presented, along with their parameter analysis. After incorporating the multimeter system, the actuator can even feedback its transformation from 2D precursor to 3D architecture by monitoring the resistance variation of LIG, revealing the integrated capability of our design in serving as sensors and actuators. Finally, the wearable glove with the LIG sensors was presented to demonstrate its ability to remotely control the soft robotic hand.

Over the past four decades, temporal variability in March sea ice area (SIA) within the Bering Sea occasionally contradicts prevailing northeasterly wind, raising doubt about the primary regulatory role of wind speed in governing maximum SIA. We argue that at least two spatial modes, extracted through the Empirical Orthogonal Function analysis, are necessary to explain the variations in the maximum SIA in the Bering Sea. Wind field emerges as the primary regulator of EOF1, governing both the direct influence of wind divergence (WD) and the indirect influence of meridional heat transport on sea ice. EOF2 is directly governed by ocean heat transport (OHT). Considering only the direct impact on sea ice, the OHT is directly responsible for the maximum SIA changes in 1995–2007, while in 2008–2014, the wind field is the largest driver. Since 2015, historically low SIA is attributed to significantly enhanced wind convergence and reduced zonal heat transport in the Gulf of Anadyr. Wind field directly controls the maximum SIA for less than half of the observation time, with OHT driving the rest. Declining trends observed in both WD and OHT suggests a future distribution pattern for the maximum SIA in the Bering Sea, characterized by an increase in the east and a decrease in the west. Long‐term retreat of sea ice on the western side of the Bering Sea is anticipated to exert significant impacts on local ecosystems, commercial activities, and even indigenous communities. Over the past 43 years, interpreting maximum sea ice area fluctuations in the Bering Sea involves understanding a combined response to wind field and ocean heat transport (OHT). Disentangling these processes is challenging due to the significant coupling between the ocean, atmosphere, and sea ice. We found that wind field, traditionally seen as the dominant force, directly impacts sea ice changes for less than 50% of the observation period. However, in view of the fact that OHT is susceptible to the influence of wind patterns, it can be concluded that wind field emerges as the primary modulating factor when indirect effects are taken into account. The characteristics of long‐term light ice years in the Bering Sea over the last 10 years are the result of the combined effects of enhanced wind convergence outside the Bering Sea continental shelf and reduced eastward heat transport in the Gulf of Anadyr. In addition, we also predicted the future distribution characteristics of sea ice in the Bering Sea. The direct influence exerted by wind field on local sea ice coverage is observed to be relatively constrained in the Bering SeaThe fluctuation in the March sea ice area (SIA) has been interpreted as a combined response to local wind divergence (WD) and zonal heat transportThe recent protracted light‐ice years is due to the intensification of wind convergence and the abatement of eastward heat transport The direct influence exerted by wind field on local sea ice coverage is observed to be relatively constrained in the Bering Sea The fluctuation in the March sea ice area (SIA) has been interpreted as a combined response to local wind divergence (WD) and zonal heat transport The recent protracted light‐ice years is due to the intensification of wind convergence and the abatement of eastward heat transport

To address the demand of maintaining the structural configuration upon extreme temperature changes, metamaterials with high thermal-mechanical stability have attracted wide attention recently. However, there are still some challenges for previous studies regarding mechanical design and practical application exploration. This manuscript proposes the design strategy for the lattice sandwich metamaterial with excellent zero thermal-induced warping, along with the metamaterial-based antenna with a high stability of electromagnetic signal transmission. Through the design strategy of discrete lattice units of the metamaterial, the ultra-low thermal warping of the metamaterial is realized upon the non-uniform temperature field. Here, the theoretical model is established to predict both heat transfer and thermal-induced deformation behavior upon complex mechanical-thermal loading conditions. The combination of theoretical predictions, finite element analysis, and experiments verifies the thermal dimensional stability of the metamaterial proposed here. Compared with the heterogeneous bilayer plate, experimental thermal warping of the metamaterial specimen is reduced by 99.7%. Additionally, compared with the bilayer-based specimen, gain attenuation, the main lobe's offset angle, and the voltage standing wave ratio offset of the metamaterial-based antenna specimen are experimentally reduced by 99.5%, 99.9% and 74.2%, revealing the huge application potential of this metamaterial in the field of spacecraft communication.

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Fluorides have been widely applied in pharmaceutical, medicinal, and materials science as well as in fine chemical manufacturing. The performance of fluorides, however, can be markedly affected by the water content. One previous study (Maiti, A.; et al. Phys. Chem. Chem. Phys.2008, 10, 5050) suggested that anhydrous 1,3-dimethylimidazolium fluoride ([DMIm]F) was unstable since the fluoride undergoes a self-decomposition reaction. Herein we first show quantum-chemical calculation evidence that although gas-phase [DMIm]F is unstable, the bulk phase of anhydrous [DMIm]F is quite stable. We then demonstrate the successful synthesis of the anhydrous [DMIm]F compound via the reaction between 1,3-dimethylimidazolium iodide and silver fluoride. Importantly, we find that anhydrous [DMIm]F possesses a high dissolution capability toward 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), although it is known that TATB is hardly dissolved in many common organic solvents. Our Born–Oppenheimer molecular dynamics (BOMD) simulations further show that the high dissolving ability of anhydrous [DMIm]F toward TATB can be attributed to the chemical reaction between the F–anion and the TATB molecules, which disrupts the strong hydrogen-bonding interaction among the TATB molecules. Alternatively, water molecules in hydrous [DMIm]F tend to form a hydration layer around the F–anion, thereby preventing F–from reacting with the TATB molecule. This result explains why TATB is barely dissolved in hydrous [DMIm]F.

Co3O4coating is one of most studied transition metal oxide due to its wide application in many fields such as gas sensors, electrochromic thin films, supercapacitors, and solar selective absorber. Aqueous electrophoretic deposition (EPD), which is considered as a cost-effective and environment-friendly coating technology, was successfully employed in preparing nano-Co3O4coating in this study. For the EPD process with the solid loading of 1 g L−1, 2.0 mM nitric acid was employed as suitable additive and 5 V was employed as deposition voltage. The prepared nano-Co3O4coating exhibited good film characteristics, which was proved by scanning electron microscopy (SEM) technology. The result suggests that a rapid preparation of nano-Co3O4coating in aqueous dispersion system can be easily accomplished. Moreover, the optimum concentrations of the added nitric acid would increase with the solid loading of Co3O4nanoparticle, but the growth rate of the former was obviously lower than that of the latter.

The manufacture of 3D mesostructures is receiving rapidly increasing attention, because of the fundamental significance and practical applications across wide-ranging areas. The recently developed approach of buckling-guided assembly allows deterministic formation of complex 3D mesostructures in a broad set of functional materials, with feature sizes spanning nanoscale to centimeter-scale. Previous studies mostly exploited mechanically controlled assembly platforms using elastomer substrates, which limits the capabilities to achieve on-demand local assembly, and to reshape assembled mesostructures into distinct 3D configurations. This work introduces a set of design concepts and assembly strategies to utilize dielectric elastomer actuators as powerful platforms for the electro-mechanically controlled 3D assembly. Capabilities of sequential, local loading with desired strain distributions allow access to precisely tailored 3D mesostructures that can be reshaped into distinct geometries, as demonstrated by experimental and theoretical studies of ∼30 examples. A reconfigurable inductive–capacitive radio-frequency circuit consisting of morphable 3D capacitors serves as an application example.

This perspective highlights various representative manufacturing methods of 3D microelectronic devices and their specific features/limitations. It offers an outlook on future developments in the manufacturing of 3D multifunctional microelectronics devices, and provides some perspectives on the remaining challenges as well as possible solutions. Mechanically guided 3D assembly based on compressive buckling is proposed as a versatile platform that can be merged with micromanufacturing technologies and/or other assembly methods to provide access to microelectronic devices with more types of integrated functions and highly increased densities of functional components.

This research examined and compared the effect of microwave and deodorant treatments on the rheological and microscopic characteristics of crumb rubber modified asphalt (CRMA) after long-term aging. Although the emissions from the asphalt modified by microwave treatment of crumb rubber (CR-micr) or high-alkane alcohol deodorant treatment of crumb rubber (CR-de) are reduced significantly compared with the ordinary CRMA, the research on their rheological and microscopic properties after aging is insufficient (especially for the CRMA with CR-de), which may pose a potential risk to their application in road engineering. To address this issue, this paper first used the rolling thin film oven and pressure aging vessel test to imitate the long-term aging of CRMAs. Then, the rheological properties of aged CRMA samples were evaluated using a dynamic shear rheometer and a bending beam rheometer. Meanwhile, the surface micromorphology, micromechanical characteristics and the chemical functional groups of CRMA samples before and after long-term aging were characterized by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). The results demonstrated that the microwave treatment can enhance the fatigue life of the long-term aged CRMA by approximately 29% under 8% CR content and 3% strain level, while effectively improve the resistance to low-temperature cracking. Meanwhile, after long-term aging, the carbonyl index of CRMA with CR-micr is 36% lower than that of CRMA with CR-de and 50% lower than that of ordinary CRMA. The micromechanical modulus of CRMA with CR-micr is also lower than that of CRMA with CR-de and ordinary CRMA. These findings manifest that the microwave treatment can improve the ability of CRMA to resist long-term aging, and the deodorant treatment does not have an adverse effect on this ability.

In this study, an accurately and digitally regulated allosteric nanoswitch based on the conformational control of two DNA hairpins was developed. By switching between UV irradiation and blue light conditions, the second molecular beacon (H#2) would bind/separate with a repression sequence (RES) via the introduced PTG molecules (a photosensitive azobenzene derivative), resulting in the target aptamer sequence in the first molecular beacon (H#1) not being able/being able to hold the stem-loop configuration, hence losing/regaining the ability to bind with the target. Importantly, we successfully monitor conformation changes of the nanoswitch by an elegant mathematical model for connecting Ki(the dissociation constant between RES and H#2) with Kd(the overall equilibrium constant of the nanoswitch binding the target), hence realizing “observing” DNA structure across dimensions from “structural visualization” to digitization and, accurately, digitally regulating DNA structure from digitization to “structural visualization”.

The mixed treatment increased rice grain yield, recovery efficiency of N, and net profit to different extents in two rice cropping systems.No significant differences in agronomic performance between urea formaldehyde and common urea.Urea formaldehyde provides little economic benefit to rice production. This study investigated the agronomic and economic efficiency of urea formaldehyde (UF) and a mixture of controlled‐release and common urea (CU) in rice (Oryza sativaL.) production. Two 3‐yr field experiments were conducted in Jinhua, China, via four treatments: no N fertilization, split applications of CU, a single UF application, and a mixed treatment comprising a polymer coating of sulfur‐coated urea (PSCU) and CU. The mixed treatment led to significantly higher grain yields by 4.7 to 12.2 and 5.7 to 8.9% for late and single rice, respectively, than those in the CU treatment. The UF treatment had small to nonsignificant improvements (0.2–2.3% for late rice; 1.7–4.3% for single rice) in grain yield relative to the CU treatment. The recovery efficiency of N (REN) in the mixed treatment was enhanced by 4.8 to 32.9% in early rice, 29.2 to 67.6% in late rice, and 13.1 to 21.2% in single rice. The mixed treatment resulted in significantly higher soil NH4+–N concentrations during the tillering to heading stage for both cropping systems. The net profit was US$111 to 257 ha−1higher than under the CU treatment. However, a single application of UF did not substantially increase net profit (US$17–47 ha−1) in early rice and single rice and decreased the profit (US$17 ha−1) in late rice, relative to the CU treatment. Overall, the mixture of PSCU and CU could be a promising alternative as a controlled‐release N fertilizer for sustainable increases in rice grain yield, REN, and net profit.

As an important channel connecting the East and South China Seas, circulations in the Taiwan Strait are strongly influenced by the East Asian monsoon and the topography of the strait, especially the Taiwan Bank (TWB), which is a remarkable topographic feature located at the southern entrance to the strait. Based on a series of pressure gauges deployed roughly 40 km offshore along the western Strait, subtidal sea-level variability under the combined impact of winter monsoon and topography was studied. The analyses show significant along-strait coherences of subtidal sea levels and their coherences with the large-scale monsoon wind for periods from 2 to 14 days. It is suggested that these fluctuations are mainly forced waves driven by the large-scale winds. In addition to the normal cross-shore wind setup, a sea-level setup in the along-strait direction is confirmed, which is induced by the combined forcing of the fluctuating winter monsoon and the blocking of the TWB. A southward current surge driven by a northerly wind event will cause a rising sea level over the TWB inducing a southward along-shore slope anomaly to the north of the TWB and a reversed slope anomaly to the south. The subtidal current through the channel to the west of the TWB is found to be influenced by the reversed slope anomalies generated via the along-shore setup.

Excellent energy-absorbing structures have been highly sought after in engineering applications to improve devices and personal safety. The ideal energy absorption mechanism should exhibit characteristics such as lightweight, high energy absorption capacity, and efficient reusability. To address this demand, a novel three-dimensional (3D) chiral lattice structure with compression-twist coupling deformation is fabricated by combining the left and right chiral units. The proposed structure was fabricated in NiTi shape memory alloys (SMAs) by using laser powder bed fusion technology. The compression experiment result indicates that the shape recovery ratio is as high as 94% even when the compression strain is over 80%. Additionally, the platform strain reaches as high as 66%, offering high-level specific energy absorption, i.e., 213.02 J/g. The obtained results are of great significance for basic research and engineering applications of energy-absorbing structures with high deformation recovery ratios.

Wearable and stretchable sensors are important components to strictly monitor the behavior and health of humans and attract extensive attention. However, traditional sensors are designed with pure horseshoes or chiral metamaterials, which restrict the biological tissue engineer applications due to their narrow regulation ranges of the elastic modulus and the poorly adjustable Poisson’s ratio. Inspired by the biological spiral microstructure, a dual-phase metamaterial (chiral-horseshoes) is designed and fabricated in this work, which possesses wide and programmable mechanical properties by tailoring the geometrical parameters. Experimental, numerical, and theoretical studies are conducted, which reveal that the designed microstructures can reproduce mechanical properties of most natural animals such as frogs, snakes, and rabbits skin. Furthermore, a flexible strain sensor with the gauge factor reaching 2 under 35% strain is fabricated, which indicates that the dual-phase metamaterials have a stable monitoring ability and can be potentially applied in the electronic skin. Finally, the flexible strain sensor is attached on the human skin, and it can successfully monitor the physiological behavior signals under various actions. In addition, the dual-phase metamaterial could combine with artificial intelligence algorithms to fabricate a flexible stretchable display. The dual-phase metamaterial with negative Poisson’s ratio could decrease the lateral shrinkage and image distortion during the stretching process. This study offers a strategy for designing the flexible strain sensors with programmable, tunable mechanical properties, and the fabricated soft and high-precision wearable strain sensor can accurately monitor the skin signals under different human motions and potentially be applied for flexible display.

Introduction:The accurate assessment of individual risk can be of great value to facilitate the prevention of recurrent coronary thrombosis events (CTEs) in patients after percutaneous coronary intervention (PCI) with Drug-Eluting Stents (DES). However, current prediction models in common use were often formulated in white populations and were of limit predicting value in Chinese patients. The current study is aimed at developing and validating a prediction model for recurrent CTEs from 2 contemporary Chinese cohorts of patients after PCI with DES. We formulated a CTEs prediction model from PROMISE trial, a PRospective Observational Multicenter cohort of Ischemic and hEmorrage risk after PCI.HypothesisWe assessed the hypothesis that the PROMISE model was an effective tool for predicting 2-year CTEs risk in Chinese patients after PCI with DES.Methods7998 Chinese patients underwent DES-PCI from PROMISE trial with 2-year follow up were used as the derivation cohort to develop the PROMISE model. The external validation was evaluated in one independent Chinese cohort with 3824 participants. Cardiac death, myocardial infarction, definite and probable in-stent thrombosis were defined as CETs. We compared candidate variables between CETs and non-CETs groups. Backward selection with an entry criterion of p<0.05 were used to formulate the model. The model performance was assessed by discrimination C statistics and calibration χ2. We also assessed the internal and external validation.ResultsOver 2-year follow up in the derivation cohort, 151 patients developed CTEs. Five variables including, previous revascularization, baseline elevated cTNI, left ventricular ejection fraction, residual SYNTAX score after PCI and estimated glomerular filtration rate were finally involved in the PROMISE model. The C statistics of the model was 0.750(95% confidence interval, 0.700-0.799), and the calibration χ2 was 7.2(p=0.612). In the subsequent external validation, the PROMISE model had C statistics of 0.607 (95%CI,0.508-0.706) , and the calibration χ2 was 14.0(p=0.121).ConclusionThe PROMISE model had a good internal validation and moderate external validation and it was an effective tool for 2-year CTEs risk prediction in Chinese patients after PCI with DES.

In conjunction with synchronous remotely sensed winds and sea surface temperature (SST), the spatiotemporal features of the Zhe-Min coastal current (ZMCC), especially responses of the ZMCC adjacent to Pingtan Island (PT) to the wintertime monsoon relaxation in 2006 and corresponding mechanism are investigated based on the field observations. In situdata are acquired from Conductivity-Temperature-Depth (CTD) cruise and Bottom-Mounted Moorings (BMM), which are conducted during a comprehensive survey for the Chinese Offshore Investigation and Assessment Project in winter 2006. It is revealed that the ZMCC is well mixed vertically in winter 2006. The ZMCC (<14°C) recedes during the relaxation of the wintertime monsoon and is accompanied by the enhanced northward shift of the warm, saline Taiwan Strait Mixed Water (TSMW, higher than 14°C and is constituted by the Taiwan Strait Warm Water and the Kuroshio Branch Water). And greatly enhanced southward intrusion of the ZMCC can be detected when the wintertime monsoon restores. Correspondingly, the thermal interface bounded by the ZMCC and the TSMW moves in the northwest/southeast direction, leading to periodic warm/cold reversals of the near-seabed temperature adjacent to the PT. By EOF (Empirical Orthogonal Function) analysis of the large-scale wind fields and wavelet power spectrum analysis of the water level, ocean current and the near-seabed temperature, responses of the ZMCC off the PT to wintertime monsoon relaxation are suggested to be attributed mainly to the southward propagating coastally trapped waves triggered by the impeding atmospheric fronts. As a result, ocean current and near-seabed temperature demonstrate significant quasi-5 d and quasi-10 d subtidal oscillations. By contrast, the onshore/offshore water accumulation resulted from Ekman advection driven by the local winds has minor contributions.In conjunction with synchronous remotely sensed winds and sea surface temperature (SST), the spatiotemporal features of the Zhe-Min coastal current (ZMCC), especially responses of the ZMCC adjacent to Pingtan Island (PT) to the wintertime monsoon relaxation in 2006 and corresponding mechanism are investigated based on the field observations. In situdata are acquired from Conductivity-Temperature-Depth (CTD) cruise and Bottom-Mounted Moorings (BMM), which are conducted during a comprehensive survey for the Chinese Offshore Investigation and Assessment Project in winter 2006. It is revealed that the ZMCC is well mixed vertically in winter 2006. The ZMCC (<14°C) recedes during the relaxation of the wintertime monsoon and is accompanied by the enhanced northward shift of the warm, saline Taiwan Strait Mixed Water (TSMW, higher than 14°C and is constituted by the Taiwan Strait Warm Water and the Kuroshio Branch Water). And greatly enhanced southward intrusion of the ZMCC can be detected when the wintertime monsoon restores. Correspondingly, the thermal interface bounded by the ZMCC and the TSMW moves in the northwest/southeast direction, leading to periodic warm/cold reversals of the near-seabed temperature adjacent to the PT. By EOF (Empirical Orthogonal Function) analysis of the large-scale wind fields and wavelet power spectrum analysis of the water level, ocean current and the near-seabed temperature, responses of the ZMCC off the PT to wintertime monsoon relaxation are suggested to be attributed mainly to the southward propagating coastally trapped waves triggered by the impeding atmospheric fronts. As a result, ocean current and near-seabed temperature demonstrate significant quasi-5 d and quasi-10 d subtidal oscillations. By contrast, the onshore/offshore water accumulation resulted from Ekman advection driven by the local winds has minor contributions.

Abstract: The effects of typhoon intrusion on the Guangdong coastal upwelling system were investigated on the basis of in situ CTD (conductivity-temperature-depth) cruise observations and especially upward-looking ADCP (Acoustic Doppler Current Profilers) measurements obtained from a comprehensive survey of the Guangdong coastal region carried out by the Chinese Offshore Investigation and Assessment Project in the summer of 2006. It was found that northeastward geostrophic advection driven by the summer monsoon has a significant near-seabed onshore component adjacent to Shantou, which in conjunction with upper-level offshore Ekman flow, constitutes the canonical Guangdong coastal upwelling system. Further analyses suggested that the Guangdong coastal upwelling system is sensitive to subtle changes in the typhoon intensity and migration pathway. On one hand, as a typhoon approaches from north of the upwelling system (e.g. Typhoon 0604 (Bilis) and Typhoon 0605 (Kaemi)) in the early phase of intrusion, the enhanced southwesterly leads to exceptional enhancement of the onshore flow; i.e., enhanced upwelling. Afterward, irrespective of the forced ocean responses resulting from the stronger local winds (Typhoon 0604) or the moderate typhoon-induced inertial oscillations (Typhoon 0605), the situation is not conducive to sustaining a stable, persistent upwelling system. On the other hand, when there is typhoon intrusion south of the upwelling system (e.g. Typhoon 0606 (Prapiroon)), the favorable southwesterly tends to be substituted by an anomalous northeasterly, which destroys the traditional coastal upwelling pattern. However, the canonical upwelling system tends to recover within 1–2 days of the typhoon passing.

Abstract: Based on the analysis theory of random energy of train derailment, an analysis theory of random energy of train derailment in wind is suggested. Two methods are proposed -the time domain method and the frequency domain method of analysis theory of random energy of train derailment in wind. The curves of σ pw -ν under various wind speeds are obtained through the computation. The original curve of σ p -ν is expanded, which turns the analysis theory of random energy of train derailment into the all-weather theory. Train derailment condition has been established under wind action. The first and second criterions of train derailment have been proposed in light of wind action. The analysis of train derailment cases at home or abroad is made, including the first analysis of Xinjiang train derailment case encountered 13-level of gale, which explained the inevitability of train derailment. The analysis theory of random energy of train derailment in wind shows its validity and accuracy. The input energy σ pw of the transverse vibration of train-track(bridge)-wind system is linked to train speed. With the establishment of the analysis theory of random energy of train derailment in wind, It is likely to initiate an all-weather speed limit map for a train or any high-speed train.

Abstract: Diurnal evolution of the barrier layer (BL) and its local feedback features in the central Taiwan Strait (119.2°E, 24.3°N) during summertime monsoon are investigated using in situ moored observations conducted by the “Yan-Ping 2” research vessel in late June 2005. During the initiation phase, for the non-solar radiation tends to be trapped in the upper mixed layer, whereas the solar radiation can penetrate deeply through the mixed layer approaching the thermocline, most heat is accumulated inside the BL inducing an inverse-thermal layer. Along with heat convergence inside the BL, thermal exchange increases between the BL and the overlaying mixed layer and finally, a prominently warming mixed layer is formed. Moreover, the BL is associated with a buoyancy frequency minimum with mild stability. Further analysis reveals that the BL’s local feedbacks can be divided into two aspects, on one hand, the BL can generate dramatic changes in the local sensible and latent heat fluxes; on the other hand, the sub-halocline and the thermocline serve as two interfaces during the downward transmission of the wind stirring turbulent kinetic energy (TKE) and as a result, most TKE is retarded by the shallow halocline and being trapped above the upper mixed layer, while the residual pierced through the base of the mixed layer is likewise blocked by the thermocline.

The aim of this study is to investigate whether Ginkgo biloba extract can augment endothelial progenitor cells numbers, and promote the cells' proliferative, migratory, adhesive, and in vitro vasculogenesis capacity. Total mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days culture, attached cells were stimulated with Ginkgo biloba extract (to make a series of final concentrations 10 mg/L, 25 mg/L, and 50 mg/L) or vehicle control for the respective time points (6 hours, 12 hours, 24 hours, and 48 h). Endothelial progenitor cells were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. They were further documented by demonstrating the expression of KDR, VEGFR-2, and AC133 with flow cytometry. Endothelial progenitor cells proliferation, migration, and in vitro vasculogenesis activity were assayed with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, modified Boyden chamber assay, and in vitro vasculogenesis kit, respectively. Endothelial progenitor cells adhesion assay was performed by replating those on fibronectin-coated dishes, and then counting adherent cells. Incubation of isolated human mononuclear cells with Ginkgo biloba extract dose- and time-dependently increased the number of endothelial progenitor cells, maximum at 25 mg/L, 24 hours (approximately 1-fold increase, P< 0.01). In addition, Ginkgo biloba extract also dose- and time-dependently promoted endothelial progenitor cells proliferative, migratory, adhesive, and in vitro vasculogenesis capacity. The results of the present study defined a novel functional effect of Ginkgo biloba extract the augmentation of endothelial progenitor cells with enhanced functional activity.

In the fields of aerospace, flexible electronics, intelligent manufacturing, and MEMS, the mechanical metamaterials with remarkable zero thermal expansion of coefficient (CTE) are of increasing interest due to their advantages in maintaining their original shapes upon a temperature change. Though recently published researches have demonstrated several designs in achieving a desirable CTE, it is still very challenging to develop the mechanical metamaterial with high-level thermal–mechanical stability (i.e., CTE < 0.5 ppm/°C). Additionally, most of these studies only focused on obtaining a remarkable zero CTE through optimizing the geometrical parameters, and did not provide enough performances in consideration of their mechanical behaviors (e.g., lightweight, high specific modulus), imposing certain limitations on their operation in devices that require combined thermal–mechanical attributes. This paper demonstrates a mechanical metamaterial design concept with lightweight, high specific modulus properties and high-level thermal–mechanical stability. Each of the unit cell in our designs composed of two or four bilayer beams filled by hourglass lattices in Al and Ti materials offers a tunable CTE from negative to positive, revealing its capability to offer remarkable zero CTE. A theoretical model that preciously predicts the design’s thermal and mechanical performances provides a clear understanding of the effects of geometric parameters on their corresponding effective properties, facilitating the design of metamaterials with desired mechanical and thermal expansion performances. Excellent agreements between theoretical predictions, FEAs, and experiments demonstrate the advantages of our design in achieving the combined attributes of lightweight (i.e., relative density ρ¯Uniaxial¡ 0.123 for the design with uniaxial thermal–mechanical stability and ρ¯Biaxial¡ 0.069 for the one with biaxial thermal–mechanical stability), high specific modulus (i.e., 1104 kN⋅mm/kg and 1203 kN⋅mm/kg for the designs with uniaxial and biaxial thermal–mechanical stability), and a remarkable zero CTE (αeffective¡ 0.32 ppm/°C). Ashby plot of the effective CTE with respect to density, serving as an especially useful tool in selecting materials according to the requirements of practical applications, provides quantitative evidences for our design’s outstanding thermal–mechanical performances as compared to the previously reported studies.

•Laser-induced porous graphene (LIG) is formed on the Polyimide/Polydimethylsiloxane (PI/PDMS) composite.•The PI/PDMS composite with LIG shows a tunable mechanical and electronic performances.•The good cyclic stability and almost linear response of the resistance of the prepared LIG.•A kirigami-inspired strain sensor with LIG was designed and optimized to increase the maximum strain value.

The assembly of three dimensional (3D) structures through compressive buckling of 2D precursors can serve as a promising and robust tool to realize different classes of advanced materials in a broad range of applications with complex geometries and a span of length scales from sub-micron to macro scales. In this study, a shape memory polymer (SMP) material was used as the precursor to form different configurations of 3D kirigami microstructures. 3D SMP structures can serve in a wide range of applications, such as biomedical and aerospace, which require a level of robustness and compliance. To this end, the mechanical response of assembled 3D buckled kirigami structures were investigated through mechanical cyclic and single loading compression at room and elevated temperatures, respectively. The experiments at room temperature were performed to examine the mechanical resilience and stability of the structures upon repeated loading. The load bearing capacity, resiliency, and stability under deformation were shown to be largely affected by their structural shape. In-situ scanning electron microscopy experiments at elevated temperatures demonstrated the outstanding shape memory behavior by full recovery to their original shape, without any structural damage or fracture. Computational modeling supports the experimental findings and contributes to the understanding of deformation and fracture of the structures.

Supplemental Digital Content is available in the text.

A 2D CdO/g‐C3N4heterostructure (CdCHT) is designed as a potential photocatalyst. Using first‐principle calculations, it is found that CdCHT is a type‐II heterostructure, which promotes the separation of photoinduced carriers and thereby facilitates water reduction and oxidation at different layers. Visible light‐absorption ability is obviously improved compared with the constituent single layers. Especially, the band edge alignments of CdCHTs with biaxial strains satisfy water redox energy levels within the pH range between 4.3 and 12.3, which ensures the occurrence of the water redox reaction. Furthermore, the calculation of free energy proves the high hydrogen production activity of CdCHT. These factors render CdCHT to be suitable for water‐splitting photocatalysis. Type‐II band alignments of CdO/g‐C3N4heterostructures (CdCHTs) facilitate water reduction and oxidation at different layers. Visible light‐absorption ability is obviously improved compared with the constituent single layers. Especially, band edge positions satisfy water redox energy levels within the pH range between 4.3 and 12.3. These factors render CdCHTs to be promising water‐splitting photocatalysts.

In this work, mechanical properties of a typical multistable mechanical metamaterial were analyzed in detail. When the maximum strain of the structure was kept constant during deflection, it was found that the largest peak force and best energy absorption efficiency can be obtained by adjusting its geometrical parameters. The influence of parameters on the force–displacement curve of the unit cell under large deformation is also discussed. Moreover, to further verify the conclusions from theoretical and finite element analysis (FEA), we experimentally investigated the mechanical performances of two different multilayer structures fabricated by a high-resolution 3D printer It is noteworthy that both the FEA and experiments reveal the structure with Q=3.6has significantly better performance than the structure with Q=6both in terms of the properties of vibration isolation and energy absorption. The remarkable result of this work shows its potential in choosing the layouts of multistable mechanical metamaterials.

Recently, the integration of electronic elements with cellular scaffolds has brought forth the ability to monitor and control tissue function actively by using flexible free-standing two-dimensional (2D) systems. Capabilities for electrically probing complex, physicochemical and biological three-dimensional (3D) microenvironments demand, however, 3D electronic scaffolds with well-controlled geometries and functional-component distributions. This work presents the development of flexible 3D electronic scaffolds with precisely defined dimensions and microelectrode configurations formed using a process that relies on geometric transformation of 2D precursors by compressive buckling. It demonstrates a capability to fabricate these constructs in diverse 3D architectures and/or electrode distributions aimed at achieving an enhanced level of control and regulation of tissue function relatively to that of other approaches. In addition, this work presents the integration of these 3D electronic scaffolds within engineered 3D cardiac tissues, for monitoring of tissue function, controlling tissue contraction through electrical stimulation, and initiating on-demand, local release of drugs, each through well-defined volumetric spaces. These ideas provide opportunities in fields ranging from in vitrodrug development to in vivotissue repair and many others.