Growth Anisotropy and Morphology Evolution of Line Defects in Monolayer MoS2 : Atomic-Level Observation, Large-Scale Statistics, and Mechanism Understanding.

Understanding the growth behavior and morphology evolution of defects in 2D transition metal dichalcogenides is significant for the performance tuning of nanoelectronic devices. Here, the low-voltage aberration-corrected transmission electron microscopy with an in situ heating holder and a fast frame rate camera to investigate the sulfur vacancy lines in monolayer MoS2 is applied. Vacancy concentration-dependent growth anisotropy is discovered, displaying first lengthening and then broadening of line defects as the vacancy densifies. With the temperature increase from 20 °C to 800 °C, the defect morphology evolves from a dense triangular network to an ultralong linear structure due to the temperature-sensitive vacancy migration process. Atomistic dynamics of line defect reconstruction on the millisecond time scale are also captured. Density functional theory calculations, Monte Carlo simulation, and configurational force analysis are implemented to understand the growth and reconstruction mechanisms at relevant time and length scales. Throughout the work, high-resolution imaging is closely combined with quantitative analysis of images involving thousands of atoms so that the atomic-level structure and the large-area statistical rules are obtained simultaneously. The work provides new ideas for balancing the accuracy and universality of discoveries in the TEM study and will be helpful to the controlled sculpture of nanomaterials.

Multifunctional integrated metamaterials for radar-infrared-visible compatible multispectral stealth.

Metamaterials offer exciting opportunities for developing multispectral stealth due to their unique electromagnetic properties. However, currently transparent radar-infrared-visible compatible stealth metamaterials typically involve complex hierarchical designs, leading to thickness and transparency limitations. Here, we propose an integrated metamaterial for multispectral stealth with high transparency. Our design features an ITO/dielectric/ITO sandwich structure, with the upper-layer ITO acting as a resonator for broadband microwave absorption while maintaining a high filling ratio to suppress infrared (IR) radiation. Experimental results demonstrate excellent performance, with over 90% microwave absorption in 8-18 GHz, an IR emissivity of approximately 0.36 in 3-14 µm, an average optical transmittance of 74.1% in 380-800 nm, and a thickness of only 2.4 mm. With its multispectral compatibility, the proposed metamaterial has potential applications in stealth and camouflage fields.

Lack of Remuscularization Following Transplantation of Human Embryonic Stem Cell-Derived Cardiovascular Progenitor Cells in Infarcted Nonhuman Primates.

RATIONALE: Human pluripotent stem cell-derived cardiovascular progenitor cells (hPSC-CVPCs) should be thoroughly investigated in large animal studies before testing in clinical trials. OBJECTIVE: The main of this study is to clarify whether hPSC-CVPCs can engraft for long time in the heart of primates after myocardial infarction (MI) and compare the effectiveness and safety of immunosuppression with cyclosporine alone or multiple-drug regimen (MDR) containing cyclosporine, methylprednisolone, and basiliximab in cynomolgus monkeys that had received intramyocardial injections of 1×107 EGFP (enhanced green fluorescent protein)-expressing hPSC-CVPCs after MI. A third group of animals received the immunosuppression MDR but without cell therapy after MI (MI+MDR group). METHODS AND RESULTS: Measurements of EGFP gene levels and EGFP immunofluorescence staining indicated that the hPSC-CVPC engraftment rate was greater in the MI+MDR+CVPC group than that in the MI+cyclosporine+CVPC group. However, even in the MI+MDR+CVPC group, no transplanted cells could be detected at 140 days after transplantation. Concomitantly, immunofluorescent analysis of CD3, CD4, and CD8 expression indicated that T-lymphocyte infiltration in the CVPC-transplanted hearts was less in the MDR-treated animals than in the cyclosporine-alone-treated animals. The recovery of left ventricular function on day 28 post-MI in the MI+MDR+CVPC group was better than that in the MI+MDR group. Apoptotic cardiac cells were also less common in the MI+MDR+CVPC group than in the MI+MDR group, although both immunosuppression regimens were associated with transient hepatic dysfunction. CONCLUSIONS: This is the largest study of hPSCs in nonhuman primates in cardiovascular field to date (n=32). Compared with cyclosporine alone, MDR attenuates immune rejection and improves survival of hPSC-CVPCs in primates; this is associated with less apoptosis of native cardiac cells and better recovery of left ventricular function at 28 days. However, even with MDR, transplanted hPSC-CVPCs do not engraft and do not survive at 140 days after transplantation, thereby excluding remuscularization as a mechanism for the functional effect.

LncRNA CASC11 improves atherosclerosis by downregulating IL-9 and regulating vascular smooth muscle cell apoptosis and proliferation.

LncRNA CASC11 is an oncogene in several types of cancer, while its role in atherosclerosis is unknown. In the present study we found that CASC11 was downregulated, while IL-9 was upregulated in plasma of atherosclerosis patients compared with healthy controls. Altered plasma levels of CASC11 and IL-9 distinguished atherosclerosis patients from healthy controls. CASC11 and IL-9 were significantly and inversely correlated in atherosclerosis patients but not in healthy controls. Exogenous IL-9 treatment failed to significantly affect expression levels of CASC11 in vascular smooth muscle cells (VSMC), while CASC11 overexpression resulted in the downregulation of IL-9. CASC11 overexpression also resulted in the downregulation of proliferation and promoted apoptosis of VSMC. Therefore, CASC11 may improve atherosclerosis by downregulating IL-9 and regulating VSMC apoptosis and proliferation.

A Large-Scale Investigation of Hypoxia-Preconditioned Allogeneic Mesenchymal Stem Cells for Myocardial Repair in Nonhuman Primates: Paracrine Activity Without Remuscularization.

RATIONALE: The effectiveness of transplanted bone marrow mesenchymal stem cells (MSCs) for cardiac repair has been limited; thus, strategies for optimizing stem-cell-based myocardial therapy are needed. OBJECTIVE: The present study was designed to test our central hypothesis that hypoxia-preconditioned MSCs (HP-MSCs) are more effective than MSCs cultured under ambient oxygen levels for the treatment of myocardial injury in a large-scale (N=49), long-term (9 months), nonhuman primate (Cynomolgous monkeys) investigation. METHODS AND RESULTS: MSCs were engineered to express green fluorescent protein, cultured under ambient oxygen or 0.5% oxygen (HP-MSCs) for 24 hours and then tested in the infarcted hearts of Cynomolgus monkeys (1×10(7) cells per heart). Hypoxia preconditioning increased the expression of several prosurvival/proangiogenic factors in cultured MSCs, and measurements of infarct size and left-ventricular function at day 90 after myocardial infarction were significantly more improved in monkeys treated with HP-MSCs than in monkeys treated with the control vehicle; functional improvements in normal cultured bone marrow mesenchymal stem cells-treated monkeys were not significant. HP-MSCs transplantation was also associated with increases in cardiomyocyte proliferation, vascular density, myocardial glucose uptake, and engraftment of the transplanted cells and with declines in endogenous cell apoptosis, but did not increase the occurrence of arrhythmogenic complications. CONCLUSIONS: Hypoxia preconditioning improved the effectiveness of MSCs transplantation for the treatment of myocardial infarction in nonhuman primates without increasing the occurrence of arrhythmogenic complications, which suggests that future clinical trials of HP-MSCs transplantation are warranted.

Hemolysis Combined with Renal Injury after Mitral Valve Repair.

Hemolysis combined with renal injury is a rare but serious complication after mitral valve repair. Here, we report two representative cases of hemolysis combined with renal injury. Although timely reoperation was not possible for several reasons, different clinical outcomes were observed that could aid in future decisions.

Stretchable Fiber Supercapacitors with High Volumetric Performance Based on Buckled MnO2 /Oxidized Carbon Nanotube Fiber Electrodes.

A stretchable fiber supercapacitor (SC) based on buckled MnO2 /oxidized carbon nanotube (CNT) fiber electrode is fabricated by a simple prestraining-then-buckling method. The prepared stretchable fiber SC has a specific volumetric capacitance up to 409.4 F cm-3 , which is 33 times that of the pristine CNT fiber based SC, and shows the outstanding stability and repeatability in performance as a stretchable SC.

Performance Assessment of a Humidity Measurement System and Its Use to Evaluate Moisture Characteristics of Wheelchair Cushions at the User-Seat Interface.

Little is known about the changes in moisture that occur at the body-seat interface during sitting. However, as increased moisture can add to the risk of skin damage, we have developed an array of MEMS (Micro-Electro-Mechanical System) humidity sensors to measure at this interface. Sensors were first evaluated against traceable standards, followed by use in a cross-over field test (n = 11; 20 min duration) using different wheelchair cushions (foam and gel). Relative humidity (RH) was measured at the left mid-thigh, right mid-thigh and coccyx. Sensors were shown to be unaffected by loading and showed highly reliable responses to measured changes in humidity, varying little from the traceable standard (<5%). Field-test data, smoothed through a moving average filter, revealed significant differences between the three chosen locations and between the gel and foam cushions. Maximum RH was attained in less than five minutes regardless of cushion material (foam or gel). Importantly, RH does not appear to distribute uniformly over the body-seat interface; suggesting multiple sensor positions would appear essential for effectively monitoring moisture in this interface. Material properties of the cushions appear to have a significant effect on RH characteristics (profile) at the body-seat interface, but not necessarily the time to peak moisture.

All-Solid-State Infrared Electrochromic Devices Based on Thin Metal Films.

Infrared electrochromic devices (IR-ECDs) are pivotal for dynamic thermal regulation. However, the quest for all-solid-state IR-ECDs with high stability and a broadly tunable range of emissivity remains a challenge. This study presents the development of an all-solid-state infrared electrochromic device (IR-ECD) with the structure of ITO/HxWO3/Ta2O5/Pd/Mg3Ni based on the hydrogen-induced metal-insulator transition of Mg-Ni alloy films. The emissivity modulation is improved by film stack optimization, with changes of 0.32 and 0.47 in the 3-5 and 7.5-14 µm bands, respectively. The introduction of an ultrathin Ti isolation layer between the catalytic and electrolyte layers enhances the cyclic stability. Our findings offer a novel strategy for the design and fabrication of all-solid-state IR electrochromic devices and highlight the potential of Mg-Ni alloy-based all-solid-state IR-ECDs in advanced energy and information fields.

Inhibition of Taurine-upregulated Gene 1 Upregulates MiR-34a-5p to Protect against Myocardial Ischemia/Reperfusion via Autophagy Regulation.

BACKGROUND: Taurine upregulated gene 1 (TUG1) has been identified on long noncoding RNA (lncRNA); however, its function in myocardial cells following ischemia/ reperfusion (I/R) injury has not been explored. This study aimed to investigate the role of LncTUG1 in I/R injury by focusing on its relationship with autophagy induction by regulating miR-34a-5p expression. METHODS: We established a myocardial I/R model and H9C2 hypoxia-ischemic and reoxygenation (HI/R) conditions to induce I/R injury. TTC, Western blot, CCK-8 assay, quantitative reverse transcription PCR, flow cytometry, and confocal microscopy were used to assess the size of myocardial infarct, level of some apoptotic-related and autophagy-associated proteins, cell viability, the level of LncRNA TUG1, apoptosis, and autophagy, respectively. RESULTS: The results revealed that a TUG1 knockdown protected against I/R-induced myocardial injury by decreasing the impairment in cardiac function. LncRNA TUG1 expression was increased in a myocardial I/R model and HI/R in H9C2 cells. Moreover, inhibition of LncTUG1 enhanced H9C2 cell viability and protected the cells from HI/R-induced apoptosis. Silencing LncRNA TUG1 promoted HI/R-induced autophagy. Furthermore, TUG1 siRNA upregulated the level of miR-34a-5p compared to the HI/R group. The protective effect of LncRNA TUG1 inhibition on H9C2 cells following HI/R was eliminated by blocking autophagy with an miR-34a-5p inhibitor. CONCLUSION: These findings indicated that inhibiting TUG1 may reduce the extent of myocardial I/R injury by regulating miR-34a-5p. Taken together, these results suggest that LncRNA TUG1 may represent a novel therapeutic target for myocardial I/R injury.

Green and Low-Cost Modified Pisha Sandstone Geopolymer Gel Materials for Ecological Restoration: A Phase Review.

Pisha sandstone (PS) is a special interbedded rock in the middle reaches of the Yellow River that experiences severe weathering and is loose and broken. Due to severe multiple erosion events, the Pisha sandstone region is called "the most severe water loss and soil erosion in the world" and "the ecological cancer of the earth". As a special pozzolanic mineral, PS has the potential to be used as precursors for the synthesis of green and low-carbon geopolymer gel materials and applied in ecological restoration. This paper aims to undertake a phase review of the precursors for geopolymer gel materials. The genesis and distribution, physical and chemical characterization, erosion characteristics, and advances in the ecological restoration of PS are all summarized. Furthermore, current advances in the use of PS for the synthesis of geopolymer gel materials in terms of mechanical properties and durability are discussed. The production of Pisha sandstone geopolymer gels through the binder jetting technique and 3D printing techniques is prospected. Meanwhile, the prospects for the resource application of PS in mine rehabilitation and sustainable ecology are discussed. In the future, multifactor-driven comprehensive measures should be further investigated in order to achieve ecological restoration of the Pisha sandstone region and promote high-quality development of the Yellow River Basin.

Pollution characteristics, distribution and risk level of heavy metals in sediments of the Yangtze River estuary.

Pollution characteristics, distribution, risk and sources of 7 heavy metals in sediments of Yangtze River Estuary were investigated. Total concentration ranges of As, Cr, Cu, Cd, Pb, Zn and Ni were [0, 16.5], [1.48, 51.3], [2.66, 318], [0, 0.99], [35.6, 992], [8, 91.3] and [1.88, 108] mg/kg, respectively. Based on the potential ecological risk index and Geoaccumulation index, it was determined that Pb is the most polluted heavy metal. According to class I standard of "Marine sediment quality" of China, mean baseline levels multiples were Pb (8.34) > Cu (0.57) > Cr (0.37) > Zn (0.355) > Ni (0.352) > As (0.28) > Cd (0.00). The study also found the heavy metal content of Pb is the most serious, but most of the Pb content comes from the residual state, which has minimal impact on the environment. The East Nanhui Shoal was identified as the most polluted sub-area in terms of Pb pollution, followed by other specific locations. Considering the pollution level and transport costs, the study concluded that dredge soils of the Yangtze River Estuary Deepwater Channel are not suitable for the restoration of East Hengsha Shoal.

Tunable Microwave Absorbing Devices Enabled by Reversible Metal Electrodeposition.

Tunable microwave absorbers have gained significant interest due to their capability to actively control microwaves. However, the existing architecture-change-based approach lacks flexibility, and the active-element-based approach is constrained by a narrowband operation or small dynamic modulation range. Here, a novel electrically tunable microwave absorbing device (TMAD) is demonstrated that can achieve dynamic tuning of the average reflection amplitude between -13.0 and -1.2 dB over a broadband range of 8-18 GHz enabled by reversible metal electrodeposition. This reversible tunability is achieved by electrodepositing silver (Ag) layers with controlled morphology on nanoscopic platinum (Pt) films in a device structure similar to a tunable Salisbury screen, employing Ag electrodeposited on Pt films as the modifiable resistive layer. Furthermore, this TMAD possesses a simple device architecture, excellent bistability, and multispectral compatibility. Our approach offers a new strategy for dynamically manipulating microwaves, which has potential utility in intelligent camouflage and communication systems.

A Hyperspectral Camouflage Colorant Inspired by Natural Leaves.

The unmet spectral mimicry of foliar green in camouflage materials is hampered by the lack of colorants with similar spectral properties to chlorophyll, resulting in substantial risks of exposure from hyperspectral target detection. By drawing inspiration from leaf chromogenesis, a microcapsule colorant with a chloroplast-like structure and chlorophyll-like absorption is developed, and a generic bilayer coating is designed to provide high spectral similarity to leaves with different growth stages, seasons, and species. Specifically, the microcapsule colorant preserves the monomeric absorption of the internal phthalocyanine and features the manufacturability of conventional pigments, such as amenability to painting and patterning, and compatibility to different substrates. The pigmented artificial leaves successfully deceive the hyperspectral classification algorithm in a foliar background, and outperforming the state-of-art spectral simulation materials. This coloration strategy expands the knowledge base of the spectral fine tuning of composite colorants, which are essential for their application in spectral-resolved optical materials.

Transparent dynamic infrared emissivity regulators.

Dynamic infrared emissivity regulators, which can efficiently modulate infrared radiation beyond vision, have emerged as an attractive technology in the energy and information fields. The realization of the independent modulation of visible and infrared spectra is a challenging and important task for the application of dynamic infrared emissivity regulators in the fields of smart thermal management and multispectral camouflage. Here, we demonstrate an electrically controlled infrared emissivity regulator that can achieve independent modulation of the infrared emissivity while maintaining a high visible transparency (84.7% at 400-760 nm). The regulators show high degree of emissivity regulation (0.51 at 3-5 µm, 0.41 at 7.5-13 µm), fast response ( < 600 ms), and long cycle life ( > 104 cycles). The infrared emissivity regulation is attributed to the modification of the carrier concentration in the surface depletion layer of aluminum-doped zinc oxide nanocrystals. This transparent infrared emissivity regulator provides opportunities for applications such as on-demand smart thermal management, multispectral displays, and adaptive camouflage.

Broadband metamaterial absorber based on coupling resistive frequency selective surface.

We report the design, fabrication, and measurement of a broadband metamaterial absorber, which consists of lossy frequency selective surface (FSS) and a metallic ground plane separated by a dielectric layer. The compact single unit cell of the FSS contains crisscross and fractal square patch which couple with each other. Both qualitative analysis by equivalent circuit and accurate numeric calculation show that the coupling between the crisscross and the fractal square patch can enhance the bandwidth with the reflectivity below -10dB in the frequency range of 2-18GHz by producing a third absorption null. In the end, the designed absorber was realized by experiment.

Ultrathin and broadband high impedance surface absorbers based on metamaterial substrates.

An ultrathin and simultaneously broadband high impedance surface absorber based on a metamaterial (MM) substrate is presented at microwave frequencies. The MM substrate is designed using metallic split ring resonators (SRRs) vertically embedded into a dielectric slab. Both the simulated and experimental results display two absorption peaks and an expanded absorption bandwidth of less than -10 dB compared to conventional ultrathin absorbers. By analyzing the field distributions and the substrate impedance characteristics, it is found that this feature is mainly related to the LC resonance of the substrate caused by the embedded SRRs. Our results demonstrate the great feasibility of broadening the absorption bandwidth of the ultrathin high impedance surface absorbers by the MMs incorporation.

Facile and economical synthesis of an electrochromic copolymer for black based on electropolymerization of thiophene and 3,4-ethylenedioxythiophene.

We report the facile and economical synthesis of an electrochromic copolymer for black based on electrochemical copolymerization of thiophene and 3, 4-ethylenedioxythiophene in boron trifluoride diethyl etherate. The resultant copolymer presents multicolor electrochromism with reversible color change between drab color and blue black. Furthermore, in the polar state the resultant copolymer shows strong and broad absorption in the whole visible region and then exhibits black color. The copolymer presents a transmittance variation of 25% at 522 nm, and corresponding response times for bleaching and coloration are 4.2 and 3.3 s, respectively. Good electrochemical stability can be achieved by the copolymer film, which retains 87% of its original electroactivity after 2000 cycles.

[One-stop hybrid cardiac surgery for adults with complex heart disease].

OBJECTIVE: To evaluate the efficacy and security of one-stop hybrid cardiac surgery for the treatment of adult patients with complex heart disease. METHODS: From November 2011 to March 2012, a total of 5 patients [4 male, mean age: (58.8 ± 14.7) years] underwent one-stop hybrid approach in the hybrid operating room. Two patients suffered from multi-coronary lesions, 2 patients were diagnosed with both valvular heart disease and coronary disease, and another 1 patient had valve disease and congenital heart disease (patent ductus arteriosus). Minimally invasive cardiac surgery (coronary artery bypass grafting for the left anterior descending or valvular surgery) and percutaneous intervention were performed in an enhanced operative unit. The efficacy and security of one-stop hybrid cardiac surgery were evaluated after the procedure. RESULTS: The one-stop hybrid procedure was successful in all patients. Left internal mammary artery grafts were unobstructed. A total of 6 non-left anterior descending coronary lesions were treated by percutaneous coronary intervention and 6 drug-eluting stents were implanted. There was no death, perioperative myocardial infarction, heart failure, prosthetic valve dysfunction, respiratory failure, stroke or repeat surgery during the procedure period. All patients remained free from angina, prosthetic valve dysfunction and patent ductus arteriosus recanalisation during the 3.2 months (rang 1 to 5 months) follow-up period. CONCLUSION: One-stop hybrid cardiac surgery provides a reasonable, feasible and safe alternative for treating adult patients with complex heart disease.

Investigating the Mechanical Property and Enhanced Mechanism of Modified Pisha Sandstone Geopolymer via Ion Exchange Solidification.

The Yellow River has the highest sediment concentration in the world, and the Yellow River coarse sediment mainly comes from a particular kind of argillaceous sandstone, Pisha sandstone. This paper reports an investigation of the possibility of development of low-cost engineering materials using Pisha sandstone via ion exchange modification. The effect of modifiers with different concentration on the inhibition of volume expansion and the strength enhancement of modified Pisha sandstone were studied via ion exchange solidification. The effects of the concentration of ten types of modifier solutions and curing age were considered. The hydration of the mineral components, particle surface potential and reaction products were studied, respectively, by XRD, zeta potential, TG/DTG and SEM. Expansion volume and shear strength tests were conducted to assess the volume stability and mechanical property of modified Pisha sandstone. It showed that the expansion of Pisha sandstone was controlled and that the volume stability and shear strength were improved via ion exchange modification. The results of XRD, TG/DTG and SEM showed that the spacing of the crystal layers of the Pisha sandstone clay mineral and the mass lost had decreased significantly. When the concentration of the modifier was 0.05 mol/L, the volume reduced by 54.55% maximum and the shear strength reached the peak of 138 kPa.