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Global deltas are facing severe challenges under the impacts of riverine sediment decline and large estuarine projects. Comparing with abundant research on the Yangtze subaqueous delta, the shoals in shallow waters are poorly understood. The Hengsha Shoal, Yangtze Delta, China, expands during the past ∼65 years, with only slight changes during the pre-projects period and remarkable variations in the projects period. It's now half-surrounded by the Hengsha Reclamation Project and the Deep Waterway Project, both facilitating the recent expansion. The current vertical net rate of change in the study area is −2.2 cm/yr, suggesting an overall balance between sediment deposition and erosion. Spatially, the Hengsha Shoal is currently changing from horizontal expansion to vertical accretion. Considering the spatial patterns of erosion/deposition and residual currents and sediment, modern geomorphic changes in the Hengsha Shoal appear to be dominated by internal sediment transport from deep to shallow waters. Considering further possible changing conditions, the future evolution of this shoal and the resulting potential ecological impacts should be studied further. This case study demonstrates that sediment dynamics in semi-artificial shoals can be totally different from the subaqueous delta, highlighting the importance of human engineering in governing large deltas globally. • The Hengsha Shoal expands from slight changes to remarkable alterations. • This Shoal is currently changing from horizontal expansion to vertical accretion. • This study highlights the importance of engineering in governing deltas globally. [ABSTRACT FROM AUTHOR]

We studied the influence of Al doping on the crystal structure and magnetocaloric properties of Mn 1.2 Fe 0.8 P 1 − x Ge x Al y compounds prepared by spark plasma sintering, with x = 0.24, 0.25, 0.26 and y = 0, 0.004, 0.008, 0.010 or 0.12. These compounds have the same Fe 2 P-type structure (space group P 6 ¯ 2m ) as the undoped system, and we found that the addition of Al had significant effects on the hexagonal unit cell of the compound and its physical properties. As y increased, the lattice parameter a and cell volume increased, the lattice parameter c decreased, the thermal hysteresis (Δ T hys ) decreased, and the Curie temperature ( T c ) became significantly higher than at y = 0. The variations of T c and Δ T hys correlated almost linearly with variation in the c / a ratio, indicating that T c can be increased with Al doping. In addition, Al doping did not have any adverse effects on other magnetocaloric properties, such as the entropy change, adiabatic temperature change, and the temperature range of the coexistence of the paramagnetic and ferromagnetic phases. We also found that the magnetocaloric properties of Mn 1.2 Fe 0.8 P 1 − x Ge x Al y compounds could be improved by homogenous annealing. The particular composition Mn 1.2 Fe 0.8 P 0.74 Ge 0.26 Al 0.010 exhibited a T c close to room temperature (292.2 K) with a hysteresis of Δ T hys 2.1 K, making it a very promising material for magnetic refrigeration around room temperature. [ABSTRACT FROM AUTHOR]

In this paper, an isotherm-evolution-based algorithm is proposed for effective tracking of the phase-change interface in temperature-driven solid-liquid phase-change process in multiphase flows (e.g., droplet freezing in the air). To fulfill the temperature condition on the interface, an interface indicator φ is defined, whose variation between specified maxima and minima marks the passing through the melting temperature. Previous approaches directly generate φ from the temperature field with explicit function and an artificial phase-change temperature interval, which could be affected by uneven temperature gradient and thus loses interfacial sharpness. The new algorithm devices an isotherm evolution equation to fulfill thermodynamic principles on the phase-change interface and maintain interface sharpness. Specifically, diffusive terms with explicit parameter are used to analytically ensure a finite interfacial width; and the migration term is introduced to cope with the phase-change temperature condition. The consistency of the proposed algorithm with the sharp interface limit is verified by comparing with analytical solutions of the Stefan problem. In numerical tests of the freezing droplet on substrate, the new algorithm presents better consistency of interfacial width throughout the computational domain and during the whole evolution process, as compared with the previous approach. The accuracy, convergence and robustness of the method as well as its capability in three-dimensional simulations are also validated through quantitative comparisons with reference results in the literature. [Display omitted] • Isotherm-evolution-based phase-change interface tracking algorithm is proposed. • Physical rational of the proposed evolution equation has been established. • The new algorithm improves interfacial sharpness comparing with previous ones. • Numerical tests have been carried out to validate the accuracy of the algorithm. • Applicability to three-dimensional simulations is also verified through tests. [ABSTRACT FROM AUTHOR]

Highlights: [•] Vibration in longitudinal direction can significantly reduce the adhesion force. [•] The reduction in sticking force was greater than 20 times in horizontal direction. [•] The reduction in sticking force was greater than 5 times in vertical handling. [ABSTRACT FROM AUTHOR]

Abstract: Two CrN(001) films with different thickness were grown on MgO(001) substrates using unbalanced d.c. magnetron sputtering. The morphology and interfacial structure of the films are characterized by using conventional transmission electron microscopy, weak-beam dark-field microscopy and spherical aberration (CS )-corrected high-resolution transmission electron microscopy. The microscopy studies revealed the well-known cube-on-cube orientation relationship. While an interface dislocation network with edge dislocations was identified, only part of the lattice mismatch is relaxed. The misfit dislocation structure and growth defects are analyzed and discussed based on the weak-beam dark-field and high-resolution transmission electron microscopy results. [Copyright &y& Elsevier]

Abstract: In this study the influence of interrupted quenching (IQ) in the temperature range 150–250°C for periods of 15–1080s on artificial aging after long-term natural pre-aging was studied for the Al–Mg–Si alloy AA6061 by atom probe tomography, transmission electron microscopy, electrical resistivity and hardness measurements, and differential scanning calorimetry. Compared with a standard quenching procedure, the results showed that hardening kinetics and the age hardening response were enhanced for IQ at low temperatures but reduced at high temperatures. Quenched-in vacancies were shown to be of particular importance for the nucleation of precipitates occurring during IQ at the lower end of the temperature range, finally leading to the formation of a dense distribution of β″ during artificial aging. For standard water quenching and subsequent natural aging, nucleation is hindered by a low concentration of quenched-in vacancies in the matrix. IQ at high temperatures affects subsequent artificial aging via the formation of precipitates which do not contribute to hardening but consume a significant amount of solute. [Copyright &y& Elsevier]

Abstract: This paper presents a novel three-dimensional finite element for gradient elasticity. The new finite element BR153L9 is a straightforward extension of the two-dimensional element QU34L4 developed by Shu et al. (1999) , which is based on a mixed-type formulation. Within this paper the derivation of the mixed-type finite element scheme is reviewed and details of the implementation are given. Finally, numerical results of an extended patch test and a benchmark test with the three-dimensional finite element are presented in order to validate the formulation and prove the convergence. [Copyright &y& Elsevier]

Abstract: In this paper, top-gate thin-film transistors (TFTs) using amorphous In–Ga–Zn–O as the n-channel active layer and SiO2 as gate insulator were fabricated by radio frequency magnetron sputtering at room temperature. In this device, a SiO layer was used to be a buffer layer between active layer and gate insulator for preventing the damage of the InGaZnO surface by the process of sputtering SiO2 with relatively high sputtering power. The thickness of buffer layers was studied and optimized for enhancing the TFTs performances. Contrasting to the TFTs without buffer layer, the optimized thickness of 10nm SiO buffer layer improved the top-gate TFTs performances greatly: mobility increases 30%, reached 1.29cm2/Vs, the I on/I off ratio increases 3 orders, and the trap density at the interface of channel/insulator decreases about 1 order, indicated that the improvement of semiconductor/dielectric interface by buffering the sputtering power. [Copyright &y& Elsevier]

Abstract: A high-performance ZnO thin film transistor （ZnO-TFT） with SiO2/Ta2O5/SiO2 (STS) multilayer gate insulator is fabricated by sputtering at room temperature. Compared to ZnO-TFTs with sputtering SiO2 gate insulator, its electrical characteristics are significantly improved, such as the field effect mobility enhanced from 11.2 to 52.4cm2/V s, threshold voltage decreased from 4.2 to 2V, and sub-threshold swing improved from 0.61 to 0.28V/dec. The improvements are attributed to the high gate capacitance (from 50 to 150nF/cm2) as well as nice surface morphology by using dielectric with high～k Ta2O5 sandwiched by SiO2 layers. The capacitance–voltage characteristic of a metal–insulator–semiconductor capacitor with the structure of Indium Tin Oxide/STS/ZnO/Al was investigated and the trap charges at the interface or bulk is evaluated to be 2.24×1012 cm− 2. From the slope of C− 2 versus gate voltage, the doping density ND of ZnO is estimated to be 1.49×1016 cm− 3. [Copyright &y& Elsevier]

Thin-film transistors with bottom gate and staggered electrodes using radio frequency sputtering ZnO and SiO2 films as channel layer and gate insulator are fabricated in this work. The performance of ZnO-TFTs with different oxygen partial pressure (15%, 20% and 30%) SiO2 dielectrics are investigated and compared with each other. The experiment results show that the oxygen partial pressure plays an important role in enhancing both the field effect mobility and bias stability of the devices. The best performance device is obtained with 20% oxygen partial pressure SiO2 dielectric, which has the smallest leakage current compared with the other two types of insulators. The field effect mobility, on/off ratio and sub-threshold swing for the 20% oxygen partial pressure SiO2 dielectric based device are 8.1 cm2/V.s, 1.8×108 and 1.35 V/dec, respectively. The 20% oxygen partial pressure insulator based device also shows a much small threshold voltage shift of 2 V after a 20 V gate voltage stressed for 1 h, while these values for the 15% and 30% oxygen partial pressure insulator based devices are 7.3 V and 3 V, respectively. [Copyright &y& Elsevier]

Abstract: In this letter, blue organic light-emitting diodes (OLEDs) with a different hole injection layer (MoO3 or m-MTDATA), and a different electron transport layer (Alq3 or BPhen) have been investigated. With 9,10-bis(2-naphthyl)-2-t-butylanthracene (TBADN) doped with (3wt.%) P-bis(P-N,N-diphenyl-aminostyryl)benzene (DSA-Ph) as an emitting layer, the typical device structure is ITO/HIL (5nm)/NPB (25nm)/EML (35nm)/ETL (15nm)/LiF (0.8nm)/Al (100nm). It has been found that MoO3//BPhen based device shows the lowest driving voltage and highest power efficiency among the referenced devices. At the current density of 20mA/cm2, its driving voltage and power efficiency is 5.2V and 4.2lm/W, which is independently reduced 48% and improved 44% compared with those of the m-MTDATA//Alq3 based one, respectively. The energy level diagram of the devices and single-carrier devices are studied to explain the reasons behind this improvement. The results strongly indicate that carrier injection ability and balance shows significant affects on the performance of OLED. [Copyright &y& Elsevier]

Abstract: Blue organic light-emitting devices based on wide bandgap host material, 2-(t-butyl)-9, 10-di-(2-naphthyl) anthracene (TBADN), blue fluorescent styrylamine dopant, p-bis(p-N,N-diphenyl-amino-styryl)benzene (DSA-Ph) have been realized by using molybdenum oxide (MoO3) as a buffer layer and 4,7-diphenyl-1,10-phenanthroline (BPhen) as the ETL. The typical device structure used was glass substrate/ITO/MoO3 (5nm)/NPB (30nm)/[TBADN: DSA-Ph (3wt%)](35nm)/BPhen (12nm)/LiF (0.8nm)/Al (100nm). It was found that the MoO3∥BPhen-based device shows the lowest driving voltage and highest power efficiency among the referenced devices. At the current density of 20mA/cm2, its driving voltage and power efficiency are 5.4V and 4.7Lm/W, respectively, which is independently reduced 46%, and improved 74% compared with those the m-MTDATA∥Alq3 is based on, respectively. The J–V curves of ‘hole-only’ devices reveal that a small hole injection barrier between MoO3∥NPB leads to a strong hole injection, resulting low driving voltage and high power efficiency. The results strongly indicate that carrier injection ability and balance shows a key significance in OLED performance. [Copyright &y& Elsevier]

Abstract: White OLEDs with a different hole injection layer (MoO3 or m-MTDATA), and a different electron transport layer (Alq3 or Bphen) have been investigated. With 9,10-bis (2-naphthyl)-2-t-butylanthracene (TBADN) doped with 3% P-bis (P-N, N-diphenyl-aminostyryl) benzene (DSA-ph) and 0.05% 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7,-tetramethyl-julolidy-9-enyl)-4H-pyran (DCJTB) as white emitting layer, the MoO3/ /Bphen based device shows the lowest driving voltage and highest power efficiency among the referenced devices. At the current density of 20 mA/cm2, its driving voltage and power efficiency are 5.43 V and 4.54 lm/W respectively, which is independently reduced 40% and improved 57% compared with those of the m-MTDATA/ / Alq3 based one, respectively. The energy level diagram of the devices and single-carrier devices are studied to explain the reasons for the improvement. The results strongly indicate that carrier injection ability and balance shows a key significance in OLED performance. [Copyright &y& Elsevier]

Abstract: We demonstrated efficient red organic light-emitting diodes based on a wide band gap material 9,10-bis(2-naphthyl)anthracene (ADN) doped with 4-(dicyano-methylene)-2-t-butyle-6-(1,1,7,7-tetramethyl-julolidyl-9-enyl)-4H-pyran (DCJTB) as a red dopant and 2,3,6,7-tetrahydro-1,1,7,7,-tetramethyl-1H,5H,11H-10(2-benzothiazolyl)quinolizine-[9,9a,1gh]coumarin (C545T) as an assistant dopant. The typical device structure was glass substrate/ITO/4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine (m-MTDATA)/N,N′-bis(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB)/[ADN:Alq3]:DCJTB:C545T/Alq3/LiF/Al. It was found that C545T dopant did not by itself emit but did assist the energy transfer from the host (ADN) to the red emitting dopant via cascade energy transfer mechanism. The OLEDs realized by this approach significantly improved the EL efficiency. We achieved a significant improvement regarding saturated red color when a polar co-host emitter (Alq3) was incorporated in the matrix of [ADN:Alq3]. Since ADN possesses a considerable high electron mobility of 3.1×10−4 cm2 V−1 s−1, co-host devices with high concentration of ADN (>70%) exhibited low driving voltage and high current efficiency as compared to the devices without ADN. We obtained a device with a current efficiency of 3.6cd/A, Commission International d’Eclairage coordinates of [0.618,0.373] and peak λ max =620nm at a current density of 20mA/cm2. This is a promising way of utilizing wide band gap material as the host to make red OLEDs, which will be useful in improving the electroluminescent performance of devices and simplifying the process of fabricating full color OLEDs. [Copyright &y& Elsevier]

Abstract: An organic thin-film transistor (OTFTs) having OTS/SiO2 bilayer gate insulator and MoO3/Al electrode configuration between gate insulator and source–drain (S–D) electrodes has been investigated. Thermally grown SiO2 layer is used as the OTFT gate dielectric and copper phthalocyanine (CuPc) for an active layer. We have found that using silane coupling agents, octadecyltrichlorosilane (OTS) on SiO2, surface energy of SiO2 gate dielectric is reduced; consequently, the device performance has been improved significantly. This OTS/SiO2 bilayer gate insulator configuration increases the field-effect mobility, reduces the threshold voltage and improves the on/off ratios simultaneously. The device with MoO3/Al electrode has similar source–drain current (I DS) compared to the device with Au electrode at same gate voltage. Our results indicate that using double-layer of insulator and modified electrode is an effective way to improve OTFT performance. [Copyright &y& Elsevier]

In the last few years, Cu is handled as a promising element to improve the corrosion resistance of duplex steels. Although there is a very limited number of studies in the literature describing the influence of Cu on the microstructure of duplex steels in the aged condition, to the authors' knowledge, no comprehensive study has been presented so far that describes in detail its influence on the microstructure and correlated mechanical properties in the solution-annealed condition. Consequently, this work is intended to fill that gap to provide a fundamental base for material design of novel duplex steels. Microstructural investigations showed a preferred formation of austenite combined with an elemental redistribution of Cr and Mo. Especially at the highest Cu content investigations revealed precipitation of Cu particles causing – so far unknown – an intragranular austenite in ferrite. It is proposed that the enrichment of austenite forming elements, i.e. Ni, at their phase boundaries as well as a low misfit between Cu particles and the intragranular austenite nuclei play a significant role during its nucleation. Due to the identified microstructural changes triggered by Cu an increased imbalance of the flow stress between ferrite and austenite, and thus a decrease of the macroscopic yield strength can be proposed. In turn an increased work hardening with Cu addition causes an unaffected ultimate tensile strength. [Display omitted] • Cu increases the austenite content as well as the elemental partitioning of Cr and Mo. • Cu alloying results in precipitation of Cu particles and a formation of intragranular austenite in ferrite. • The formation of intragranular-γ is promoted by an enrichment of Ni and a low misfit to pre-existing Cu particles. • A decreasing global yield strength is due to an increased imbalance of hardness between ferrite and austenite. • An unaffected global ultimate tensile strength is due to an increased work hardening caused by incoherent Cu particles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rhenium behaves as a plastic metal under HPT. • Rhenium demonstrates high plasticity despite huge work-hardening under HPT. • The ultrafine-grained structure is formed in rhenium under HPT. The coarse-grained rhenium's deformation behavior under the high-pressure torsion at room temperature, including its structure evolution, is examined. It showed that this refractory HCP-metal behaves like a ductile metal: i.e., it can withstand severe deformation, while the ultra-fine grain structure is forming in the samples. [ABSTRACT FROM AUTHOR]

The Yangtze River has experienced a sharp sediment decrease as a result of extensive dam constructions since the 1980s, similar to the sediment decline in the Mississippi River since the 1950s. Historical land losses in the Mississippi Delta have been reported extensively, but this issue in the Yangtze Delta is still under debate. Here we presented the morphological responses of deltaic wetlands to the sediment decline with the comparison of hydrodynamic forces in the Yangtze and Mississippi deltas. We found that the wetlands of the Yangtze Delta continued their expansion even after the sediment decline since 2003 when the Three Gorges Dam began operation, in contrast to the historical scenario in the Mississippi. Based on observations at water depth around 10 m in both of the open subaqueous deltas, the bed shear stresses caused by waves and currents (τcw) during neap and spring tides were 0.18–0.30 N/m2 in the Yangtze Delta and 0.09–0.10 N/m2 in the Mississippi Delta under fair weather conditions. The periods of τcw > τcr (the critical bed shear stress for erosion) occupied on average 80% of a tidal cycle in the Yangtze Delta but only 47% of a cycle in the Mississippi Delta. The rates of relative sea-level rise and riverine sediment decrease in these two deltas are similar, but the sediment-supply capacity to the deltaic wetlands from the Yangtze's subaqueous delta is much larger than that of the Mississippi Delta. Thus, we infer that in contrast to the historical land loss after sediment decline in the Mississippi Delta, the Yangtze deltaic wetlands stand still with a good opportunity to survive for years to decades with the aid of abundant sediment from the subaqueous delta due to higher capacity of seabed erodibility by stronger coastal hydrodynamics. [ABSTRACT FROM AUTHOR]

Abstract: Low-voltage-drive ZnO thin-film transistors (TFTs) with room-temperature radio frequency magnetron sputtering SiO2 as the gate insulator were fabricated successfully on the glass substrate. The ZnO-TFT operates in the enhancement mode with a threshold voltage of 4.2 V, a field effect mobility of 11.2 cm2/V s, an on/off ratio of 3.1 × 106 and a subthreshold swing of 0.61 V/dec. The drain current can reach to 1 mA while the gate voltage is only of 12 V and drain voltage of 8 V. The C–V characteristics of a MOS capacitor with the structure of ITO/SiO2/ZnO/Al was investigated. The carrier concentration ND in the ZnO active layer was determined, the calculated ND is 1.81 × 1016 cm−3, which is the typical value of undoped ZnO film used as the channel layer for ZnO-TFT devices. The experiment results show that SiO2 film is a promising insulator for the low voltage and high drive capability oxide TFTs. [Copyright &y& Elsevier]

Abstract: Top-contact Copper phthalocyanine (CuPc) thin-film field-effect transistor (TFT) with SiO2/Ta2O5/SiO2 (STS) multilayer as the dielectric was fabricated and investigated. With the multi-layer dielectric, drive voltage was remarkably reduced. A relatively large on-current of 1.1×10− 7 A at a VGS of −15V was obtained due to the strong coupling capability provided by the STS multilayer gate insulator. The device shows a moderate performance: saturation mobility of μ sat =6.12×10− 4 cm2/Vs, on-current to off-current ratio of I on/I off =1.1×103, threshold voltage of V TH =−3.2V and sub-threshold swing SS=1.6V/dec. Atomic force microscope images show that the STS multilayer has a relative smooth surface. Experiment results indicate that STS multilayer is a promising insulator for the low drive voltage CuPc-based TFTs. [Copyright &y& Elsevier]

We provide an experimental and theoretical description of the high temperature fracture behaviour of TiN thin films. For this, we employ molecular dynamics and density functional theory, to show that the surface energies drop insignificantly between 0 and 1000 K. We utilise these results to predict a slight decrease of the fracture toughness over the aforementioned temperature range. For the experimental perspective, we use unbalanced DC reactive magnetron sputtering to synthesise a TiN film, on which we perform in situ high temperature microcantilever bending tests. Upon increasing the testing temperature from room temperature to 773 K our results present a slight, irreversible decrease of K IC , once the deposition temperature of the film (~653 K) is exceeded. Based on our theoretical groundwork, as well as complementary data produced by X-ray diffraction, nanoindentation, transmission electron microscopy, and wafer curvature measurements, we identify growth defect recovery as the main reason behind the decrease of K IC. We observe no change in the deformation and/or fracture mechanism of TiN across the experimentally investigated temperature range. Using an analytical model based on continuum mechanics, we estimate the influence of macro residual stresses on the temperature-dependent fracture toughness of TiN attached to a Si (100) wafer. Unlabelled Image • Temperature-dependent molecular dynamics calculations of the (100), (110), and (111) surface energies of TiN. • In situ microcantilever bending tests performed at ambient, and elevated temperatures. • Growth defect recovery identified as a decreasing factor for the fracture toughness of TiN thin flims. • Analytical continuum mechanics model consulted to estimate the temperature-dependent apparent fracture toughness of TiN attached to a Si substrate. [ABSTRACT FROM AUTHOR]

Novel low temperature sintered Li 4 Mg 3 [Ti 0.8 (Mg 1/3 Ta 2/3) 0.2 2 O 9 (LMT 0.8 (MT) 0.2) ceramics with 1–5 wt% LiF additives were successfully prepared by the solid-state reaction method. The effects of LiF additives on the phase composition, sintering characteristic, microstructure and microwave dielectric properties of LMT 0.8 (MT) 0.2 ceramics were investigated in detail for the first time. The sintering temperature of LMT 0.8 (MT) 0.2 ceramics could be effectively lowered to 950 °C by the addition of LiF. A single rock salt crystalline phase structure belonging to a space group of Fm-3m (No.225) was obtained through X-ray diffraction patterns. Dense uniform morphology was observed at 950 °C for LMT 0.8 (MT) 0.2 ceramics with 3–5 wt% LiF in terms of scanning electron microscopy photographs. Particularly, the LMT 0.8 (MT) 0.2 -4 wt% LiF ceramics sintered at 950 °C for 4 h possessed optimum microwave dielectric properties of ε r = 16.10, Q·f = 114,313 GHz (at 8.18 GHz) and τ f = −7.72 ppm/°C. In addition, the excellent chemical compatibility with silver metal electrodes indicated that the LMT 0.8 (MT) 0.2 -4 wt% LiF ceramics might be a promising candidate for the low-loss low temperature co-fired ceramics (LTCC) applications in microwave devices. Image 1 • The low-fired LiF-doped Li 4 Mg 3 [Ti 0.8 (Mg 1/3 Ta 2/3) 0.2 2 O 9 composite ceramics are fabricated. • LiF-doping lowered sintering temperature of Li 4 Mg 3 [Ti 0.8 (Mg 1/3 Ta 2/3) 0.2 2 O 9 ceramics to 950 °C. • Li 4 Mg 3 [Ti 0.8 (Mg 1/3 Ta 2/3) 0.2 2 O 9 -4 wt% LiF ceramics exhibited good dielectric properties. • The sample was compatible with Ag electrodes and suitable for LTCC applications. [ABSTRACT FROM AUTHOR]

Background: In acute ischemic stroke, there is uncertainty regarding the benefit and risk of administering intravenous alteplase before endovascular thrombectomy., Methods: We conducted a trial at 41 academic tertiary care centers in China to evaluate endovascular thrombectomy with or without intravenous alteplase in patients with acute ischemic stroke. Patients with acute ischemic stroke from large-vessel occlusion in the anterior circulation were randomly assigned in a 1:1 ratio to undergo endovascular thrombectomy alone (thrombectomy-alone group) or endovascular thrombectomy preceded by intravenous alteplase, at a dose of 0.9 mg per kilogram of body weight, administered within 4.5 hours after symptom onset (combination-therapy group). The primary analysis for noninferiority assessed the between-group difference in the distribution of the modified Rankin scale scores (range, 0 [no symptoms] to 6 [death]) at 90 days on the basis of a lower boundary of the 95% confidence interval of the adjusted common odds ratio equal to or larger than 0.8. We assessed various secondary outcomes, including death and reperfusion of the ischemic area., Results: Of 1586 patients screened, 656 were enrolled, with 327 patients assigned to the thrombectomy-alone group and 329 assigned to the combination-therapy group. Endovascular thrombectomy alone was noninferior to combined intravenous alteplase and endovascular thrombectomy with regard to the primary outcome (adjusted common odds ratio, 1.07; 95% confidence interval, 0.81 to 1.40; P = 0.04 for noninferiority) but was associated with lower percentages of patients with successful reperfusion before thrombectomy (2.4% vs. 7.0%) and overall successful reperfusion (79.4% vs. 84.5%). Mortality at 90 days was 17.7% in the thrombectomy-alone group and 18.8% in the combination-therapy group., Conclusions: In Chinese patients with acute ischemic stroke from large-vessel occlusion, endovascular thrombectomy alone was noninferior with regard to functional outcome, within a 20% margin of confidence, to endovascular thrombectomy preceded by intravenous alteplase administered within 4.5 hours after symptom onset. (Funded by the Stroke Prevention Project of the National Health Commission of the People's Republic of China and the Wu Jieping Medical Foundation; DIRECT-MT ClinicalTrials.gov number, NCT03469206.)., (Copyright © 2020 Massachusetts Medical Society.)