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Two-dimensional (2D) nanocrystals are promising for optoelectronic and microelectronic technologies. However, the performance of 2D nanocrystal light-emitting diodes (LEDs) remains limited. Here, exciton dynamics are rationally controlled by both shell engineering and device engineering, obtaining colloidal quantum well LEDs (CQW-LEDs) with superior performance. The formation of CQW films on charge transport layers shows an excellent photoluminescence quantum yield of 76.63%. An unreported relationship among Auger lifetime, electron confinement energy, and external quantum efficiency (EQE) in 2D nanocrystal devices is directly observed. The optimized CQW-LEDs possess a maximum power efficiency of 6.04 lm W−1 and a current efficiency of 9.20 cd A−1, setting record efficiencies for 2D nanocrystal red LEDs. Additionally, a remarkable EQE of 13.43% has been achieved, accompanied by an exceptionally low efficiency roll-off. Significantly, EQE for flexible CQW-LEDs is 42-fold higher than the previous best results. Furthermore, active-matrix CQW-LEDs on printed circuit boards are developed. The findings not only unlock new possibilities for controlling exciton dynamics but also provide an alternative strategy to achieve high-performance 2D nanocrystal based applications. [ABSTRACT FROM AUTHOR]

In this paper, we developed a new method to construct flexible fully-printed all-carbon thin film transistors (TFTs) with excellent properties and highly sensitive ammonia (NH3) sensors via aerosol jet printing. Here, sorted semiconducting single-walled carbon nanotubes (sc-SWCNTs), carboxyl-functionalized single-walled carbon nanotubes (P3 SWCNTs) and printed ion gels were chosen as channel materials, printed source, drain and side-gate electrodes, and dielectric layers. Flexible printed side-gate TFTs showed high on/off ratios (∼106), good mobility (up to 9.8 cm2 V−1 s−1), low hysteresis and small subthreshold swings (∼80 mV dec−1) at gate voltages of ±1 V. As-prepared TFTs exhibited an extremely high response to NH3 (up to 346.73% within 11 s) with good selectivity, ultralow limit of detection (LOD) (21.35 ppb) and low power consumption (0.49 nW) at room temperature due to the strong adsorption and enrichment of NH3 gas by ionic liquids (ILs) in the ion gels and the signal amplification of printed ion-gel TFTs. Furthermore, all devices can withstand 10 000 times bending with a radius of 5 mm, displaying good mechanical flexibility due to the high mechanical properties of carbon nanotubes. [ABSTRACT FROM AUTHOR]

An integrated study including petrography, mineral chemistry, metamorphic P–T path modelling, and zircon U–Pb dating was conducted on a granitic gneiss and enclosed eclogite from South Dulan, North Qaidam UHP (ultrahigh-pressure) belt. The result shows that the granitic gneiss underwent a clockwise P–T path with a peak-P stage at 655–745°C, 30–34 kbar, and a subsequent peak-T stage at 815–870°C, 14–18 kbar, which is similar to the P–T estimates reported for coesite-bearing continental-type eclogites in this region. The enclosed eclogite resembles an olivine–pyroxene-rich cumulate in Qaidam block. It has a similar prograde P–T path with the country gneiss and experienced a peak-P stage of 682–748°C at 27–34 kbar. Zircon U–Pb dating yields an eclogite-facies metamorphic age of 447 ± 2 Ma for the granitic gneiss and 445 ± 6 Ma for the enclosed eclogite. These ages agree with metamorphic ages obtained from paragneisses (427–439 Ma), coesite-bearing continental-type eclogites (430–451 Ma), and UHPM (ultrahigh-pressure metamorphic) oceanic crust–mantle sequence (440–445 Ma) from South Dulan, as well as UHP eclogites, garnet peridotite, and gneisses from other units (460–420 Ma) within this belt reported by others. Similar metamorphic ages as well as P–T evolution documented in gneisses and intercalated eclogites imply that both rocks experienced a coeval UHP event. Summarizing all the published geochronology data, we argue that the North Qaidam UHP belt was mainly formed by continental deep subduction at ~460 to ~420 Ma. The UHPM oceanic crust-mantle sequence in South Dulan may represent oceanic lithosphere in the transition zone between oceanic and continental crust, which was dragged upward by the exhumed continental rocks after break-off of the dense oceanic crust. [ABSTRACT FROM PUBLISHER]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Radiation-induced skin injury (RISI) is a frequent and severe complication with a complex pathogenesis that often occurs during radiation therapy, nuclear incidents, and nuclear war, for which there is no effective treatment. Hyaluronan (HA) plays an overwhelming role in the skin, and it has been shown that UVB irradiation induces increased HA expression. Nevertheless, to the best of our knowledge, there has been no study regarding the biological correlation between RISI and HA degradation and its underlying mechanisms. Therefore, in our study, we investigated low-molecular-weight HA content using an enzyme-linked immunosorbent assay and changes in the expression of HA-related metabolic enzymes using real-time quantitative polymerase chain reaction and a Western blotting assay. The oxidative stress level of the RISI model was assessed using sodium dismutase, malondialdehyde, and reactive oxygen species assays. We demonstrated that low-molecular-weight HA content was significantly upregulated in skin tissues during the late phase of irradiation exposure in the RISI model and that HA-related metabolic enzymes, oxidative stress levels, the MEK5/ERK5 pathway, and inflammatory factors were consistent with changes in low-molecular-weight HA content. These findings prove that HA degradation is biologically relevant to RISI development and that the HA degradation mechanisms are related to HA-related metabolic enzymes, oxidative stress, and inflammatory factors. The MEK5/ERK5 pathway represents a potential mechanism of HA degradation. In conclusion, we aimed to investigate changes in HA content and preliminarily investigate the HA degradation mechanism in a RISI model under γ-ray irradiation, to consider HA as a new target for RISI and provide ideas for novel drug development. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the clinical efficacy of antibiotic bone cement–coated implants compared with external fixations for treating infected bone defects. Methods: We retrospectively enrolled 119 patients with infected bone defects in our hospital from January 2010 to June 2021, of which 56 were treated with antibiotic bone cement–coated implants and 63 were with external fixation. Results: The pre-operative and post-operative haematological indexes were tested to assess the infection control; the post-operative CRP level in the internal fixation group was lower than that in the external fixation group. No statistical significance was found in the rate of infection recurrence, loosening and rupture of the fixation, and amputation between the two groups. Twelve patients in the external fixation group had pin tract infection. In the evaluation of the Paley score scale, bone healing aspect revealed no significant difference between the two groups, while in the limb function aspect, antibiotic cement–coated implant group showed a much better score than the external fixation group (P = 0.002). The anxiety evaluation scale result also showed lower score in the antibiotic cement implant group (P < 0.001). Conclusions: Compared with external fixation, antibiotic bone cement–coated implant had the same effect on controlling infection and was more effective in recovering limb function and mental health in the first-stage treatment of infected bone defects after debridement. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: The purpose of this paper is to present a simple yet effective force control scheme for collaborative robots by addressing the problem of disturbance rejection in joint torque: inherent actuator flexibility and nonlinear friction. Design/methodology/approach: In this paper, a joint torque controller with an extended state observer is used to decouple the joint actuators from the multi-rigid-body system of a constrained robot and compensate the motor friction. Moreover, to realize robot force control, the authors embed this controller into the impedance control framework. Findings: Results have been given in simulations and experiments in which the proposed joint torque controller with an extended state observer can effectively estimate and compensate the total disturbance. The overall control framework is analytically proved to be stable, and further it is validated in experiments with a robot testbed. Practical implications: With the proposed robot force controller, the robot is able to change its stiffness in real time and therefore take variable tasks without any accessories, such as the RCC or 6-DOF F/T sensor. In addition, programing by demonstration can be realized easily within the proposed framework, which makes the robot accessible to unprofessional users. Originality/value: The main contribution of the presented work is the design of a model-free robot force controller with the ability to reject torque disturbances from robot-actuator coupling effect and motor friction, applicable for both constrained and unconstrained environments. Simulation and experiment results from a 7-DOF robot are given to show the effectiveness and robustness of the proposed controller. [ABSTRACT FROM AUTHOR]

Agricultural production, rural areas, and farmers are three key aspects of agriculture related to sustainable economic and social development in China. Rural development is a process of multi-participation, which involves actors from governments, village committees, villagers, rural economic cooperatives, enterprises, financing institutions, and non-government organizations (NGOs). Based on social network analysis (SNA), this article analyzes the social network structures and characteristics of various actors in different stages of rural development in Yanhe village, Hubei Province, China. The results show that both the village committee and villagers have great influence on rural development; NGOs are the leaders of rural environmental improvement; village cooperatives are the promoters of rural economic development; enterprises are the accelerators of rural construction and development. The study outlines the rural development model in Yanhe village where the village committee is the leader and multiple forms of participation and cooperation are present; there are excellent partnerships and communication mechanisms among the participants. The endogenous and sustainable development model identified from Yanhe village is valuable for other villages in China to adopt. [ABSTRACT FROM AUTHOR]