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دخلت الصين مرحلة جديدة من التطور خلال العقود الثلاثة، مع بدئها بتنفيذ سياسة الإصلاح والانفتاح، فاحتل اقتصادها في العام 2010 م، المرتبة الثانية لأكبر اقتصاد في العالم، نتيجة سنوات طويلة من العمل الشاق، لبناء دولة اشتراكية قوية، والترويج لحوكمة جديدة، إلى جانب التطور المتسارع لكل من العلوم والتكنولوجيا والتعليم، تحت قيادة الرئيس شي جين بينغ الحكيمة التي عكست وجهة نظره الثاقبة والمتمثلة في دمج النظرية بالممارسة لمواكبة الزمن. وبناء عليه، سيعالج هذا الكتاب أهم الخطوط العريضة التي قام عليها فكر شي جين بينغ في حوكمة الصين، وبناء دولة ابتكارية تعطي الأولوية لتطوير العلوم والتكنولوجيا والتعليم، وإغنائها بالمواهب الشابة، بهدف الحفاظ على استمرارية النهضة التي تشهدها الأمة الصينية حاليا، والشير أكثر فأكثر إلى الأمام.

While photoluminescence printing is a widely applied anticounterfeiting technique, there are still challenges in developing new generation anticounterfeiting materials with high security. Here we report the construction of a photoresponsive supramolecular coordination polyelectrolyte (SCP) through hierarchical self-assembly of lanthanide ion, bis-ligand and diarylethene unit, driven by metal-ligand coordination and ionic interaction. Owing to the conformation-dependent photochromic fluorescence resonance energy transfer between the lanthanide donor and diarylethene acceptor, the ring-closure/ring-opening isomerization of the diarylethene unit leads to a photoreversible luminescence on/off switch in the SCP. The SCP is then utilized as security ink to print various patterns, through which photoreversible multiple information patterns with visible/invisible transformations are realized by simply alternating the irradiation with UV and visible light. This work demonstrates the possibility of developing a new class of smart anticounterfeiting materials, which could be operated in a noninvasive manner with a higher level of security. Photoluminescence printing is a widely applied anticounterfeiting technique but there are still challenges in developing new generation anticounterfeiting materials providing a high security level. Here, the authors demonstrate coordination dependent photochromic luminescence in a supramolecular coordination polyelectrolyte for multiple information authentication.

Background The association between corticosteroid use and intensive care unit (ICU)-acquired weakness remains unclear. We evaluated the relationship between corticosteroid use and ICU-acquired weakness in critically ill adult patients. Methods The PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and Cumulative Index of Nursing and Allied Health Literature databases were searched from database inception until October 10, 2017. Two authors independently screened the titles/abstracts and reviewed full-text articles. Randomized controlled trials and prospective cohort studies evaluating the association between corticosteroids and ICU-acquired weakness in adult ICU patients were selected. Data extraction from the included studies was accomplished by two independent reviewers. Meta-analysis was performed using Stata version 12.0. The results were analyzed using odds ratios (ORs) and 95% confidence intervals (CIs). Data were pooled using a random effects model, and heterogeneity was evaluated using the χ 2 and I 2 statistics. Publication bias was qualitatively analyzed with funnel plots, and quantitatively analyzed with Begg’s test and Egger’s test. Results One randomized controlled trial and 17 prospective cohort studies were included in this review. After a meta-analysis, the effect sizes of the included studies indicated a statistically significant association between corticosteroid use and ICU-acquired weakness (OR 1.84; 95% CI 1.26–2.67; I 2  = 67.2%). Subgroup analyses suggested a significant association between corticosteroid use and studies limited to patients with clinical weakness (OR 2.06; 95% CI 1.27–3.33; I 2  = 60.6%), patients with mechanical ventilation (OR 2.00; 95% CI 1.23–3.27; I 2  = 66.0%), and a large sample size (OR 1.61; 95% CI 1.02–2.53; I 2  = 74.9%), and not studies limited to patients with abnormal electrophysiology (OR 1.65; 95% CI 0.92–2.95; I 2  = 70.6%) or patients with sepsis (OR 1.96; 95% CI 0.61–6.30; I 2  = 80.8%); however, statistical heterogeneity was obvious. No significant publication biases were found in the review. The overall quality of the evidence was high for the randomized controlled trial and very low for the included prospective cohort studies. Conclusions The review suggested a significant association between corticosteroid use and ICU-acquired weakness. Thus, exposure to corticosteroids should be limited, or the administration time should be shortened in clinical practice to reduce the risk of ICU-acquired weakness.

Highlights The tunable mechanisms of lateral heterostructures on both homogeneous junctions and heterogeneous junctions are summarized. Electronic and photoelectronic devices with lateral heterostructures have been discussed. Different types of contacts of 2D lateral heterostructures are classified. Recent developments in synthesis and nanofabrication technologies of 2D lateral heterostructures are reviewed. Recent developments in synthesis and nanofabrication technologies offer the tantalizing prospect of realizing various applications from two-dimensional (2D) materials. A revolutionary development is to flexibly construct many different kinds of heterostructures with a diversity of 2D materials. These 2D heterostructures play an important role in semiconductor and condensed matter physics studies and are promising candidates for new device designs in the fields of integrated circuits and quantum sciences. Theoretical and experimental studies have focused on both vertical and lateral 2D heterostructures; the lateral heterostructures are considered to be easier for planner integration and exhibit unique electronic and photoelectronic properties. In this review, we give a summary of the properties of lateral heterostructures with homogeneous junction and heterogeneous junction, where the homogeneous junctions have the same host materials and the heterogeneous junctions are combined with different materials. Afterward, we discuss the applications and experimental synthesis of lateral 2D heterostructures. Moreover, a perspective on lateral 2D heterostructures is given at the end.

Antimony selenide (Sb 2 Se 3 ) has a one-dimensional (1D) crystal structure comprising of covalently bonded (Sb 4 Se 6 ) n ribbons stacking together through van der Waals force. This special structure results in anisotropic optical and electrical properties. Currently, the photovoltaic device performance is dominated by the grain orientation in the Sb 2 Se 3 thin film absorbers. Effective approaches to enhance the carrier collection and overall power-conversion efficiency are urgently required. Here, we report the construction of Sb 2 Se 3 solar cells with high-quality Sb 2 Se 3 nanorod arrays absorber along the [001] direction, which is beneficial for sun-light absorption and charge carrier extraction. An efficiency of 9.2%, which is the highest value reported so far for this type of solar cells, is achieved by junction interface engineering. Our cell design provides an approach to further improve the efficiency of Sb 2 Se 3 -based solar cells. Antimony selenide is a promising thin film solar cell absorber material in which grain orientation is crucial for high device performance. Here Li et al. grow the material in nanorod arrays along the [001] direction and obtain record high efficiency of 9.2%.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages BA.2.12.1, BA.4 and BA.5 exhibit higher transmissibility than the BA.2 lineage 1 . The receptor binding and immune-evasion capability of these recently emerged variants require immediate investigation. Here, coupled with structural comparisons of the spike proteins, we show that BA.2.12.1, BA.4 and BA.5 (BA.4 and BA.5 are hereafter referred collectively to as BA.4/BA.5) exhibit similar binding affinities to BA.2 for the angiotensin-converting enzyme 2 (ACE2) receptor. Of note, BA.2.12.1 and BA.4/BA.5 display increased evasion of neutralizing antibodies compared with BA.2 against plasma from triple-vaccinated individuals or from individuals who developed a BA.1 infection after vaccination. To delineate the underlying antibody-evasion mechanism, we determined the escape mutation profiles 2 , epitope distribution 3 and Omicron-neutralization efficiency of 1,640 neutralizing antibodies directed against the receptor-binding domain of the viral spike protein, including 614 antibodies isolated from people who had recovered from BA.1 infection. BA.1 infection after vaccination predominantly recalls humoral immune memory directed against ancestral (hereafter referred to as wild-type (WT)) SARS-CoV-2 spike protein. The resulting elicited antibodies could neutralize both WT SARS-CoV-2 and BA.1 and are enriched on epitopes on spike that do not bind ACE2. However, most of these cross-reactive neutralizing antibodies are evaded by spike mutants L452Q, L452R and F486V. BA.1 infection can also induce new clones of BA.1-specific antibodies that potently neutralize BA.1. Nevertheless, these neutralizing antibodies are largely evaded by BA.2 and BA.4/BA.5 owing to D405N and F486V mutations, and react weakly to pre-Omicron variants, exhibiting narrow neutralization breadths. The therapeutic neutralizing antibodies bebtelovimab 4 and cilgavimab 5 can effectively neutralize BA.2.12.1 and BA.4/BA.5, whereas the S371F, D405N and R408S mutations undermine most broadly sarbecovirus-neutralizing antibodies. Together, our results indicate that Omicron may evolve mutations to evade the humoral immunity elicited by BA.1 infection, suggesting that BA.1-derived vaccine boosters may not achieve broad-spectrum protection against new Omicron variants. Biochemical and structural studies of the interactions between antibodies and spike proteins from SARS-CoV-2 Omicron subvariants indicate how these variants have evolved to escape antibody-mediated neutralization.

Visual orientation seems to indicate the decline of oral communication, but oral communication has its own living space under the new media ecology. Research has found that in the digital media era, voice communication is manifested as a single-level feature that simulates current interaction and information communication. Although voice communication is a lie constructed by individuals, the interaction between the subject’s discourse and the actual field of interaction separate the emotional distance, but the situation is harmonious and inclusive. The following voice communication and new media technologies are still trustworthy. Aiming at multifactor evolutionary algorithm (MFEA), the most classical multifactor evolutionary algorithm in multitask computation, we theoretically analyze the inherent defects of MFEA in dealing with multitask optimization problems with different subfunction dimensions and propose an improved version of the multifactor evolutionary algorithm, called HD-MFEA. In HD-MFEA, we proposed heterodimensional selection crossover and adaptive elite replacement strategies, enabling HD-MFEA to better carry out gene migration in the heterodimensional multitask environment. At the same time, we propose a benchmark test problem of multitask optimization with different dimensions, and HD-MFEA is superior to MFEA and other improved algorithms in the test problem. Secondly, we extend the application scope of multitask evolutionary computation, and for the first time, the training problem of neural networks with different structures is equivalent to the multitask optimization problem with different dimensions. At the same time, according to the hierarchical characteristics of neural networks, a heterodimensional multifactor neural evolution algorithm HD-MFEA neuro-evolution is proposed to train multiple neural networks simultaneously. Through experiments on chaotic time series data sets, we find that HD-MFEA neuro-evolution algorithm is far superior to other evolutionary algorithms, and its convergence speed and accuracy are better than the gradient algorithm commonly used in neural network training.

Conventional luminescent information is usually visible under either ambient or UV light, hampering their potential application in smart confidential information protection. In order to address this challenge, herein, light‐triggered luminescence ON‐OFF switchable hybrid hydrogels are successfully constructed through in situ copolymerization of acrylamide, lanthanide complex, and diarylethene photochromic unit. The open‐close behavior of the diarylethene ring in the polymer could be controlled by UV and visible light irradiation, where the close form of the ring features fluorescence resonance energy transfer with the lanthanide complex. The hydrogel‐based blocks with tunable emission colors are then employed to construct 3D information codes, which can be read out under a 254 nm UV lamp. The exposure to 300 nm UV light leads to the luminescence quenching of the hydrogels, thus erasing the encoded information. Under visible light (>450 nm) irradiation, the luminescence is recovered to make the confidential information readable again. Thus, by simply alternating the exposure to UV and visible lights, the luminescence signals could become invisible and visible reversibly, allowing for reversible multiple information encryption and decryption. Light‐triggered luminescence ON‐OFF switchable hybrid hydrogels are synthesized through in situ copolymerization. The hydrogel‐based blocks with tunable emission colors are then employed to construct 3D information codes, allowing for reversible multiple information encryption and decryption.

The Arxan volcanic group is one of the largest active volcanic fields in China. Its last eruption occurred ∼2,000 years ago, but it still has a potential of eruption in the future. The spatial distribution and migration channel of its magmatic reservoirs are still unclear. Here we precisely locate microearthquakes and study the detailed 3‐D velocity structure of the volcanic area using a large number of high‐quality P and S wave arrival‐time data recorded at 227 portable seismometers. A swarm of microearthquakes (M < 1.5) related to magmatic activity were recorded, which lasted about 4 days during 13–16 September 2020. Our tomographic results show that 12 Arxan volcanoes share the same magmatic system. The melt fraction of a magma chamber below the Tianchi volcano at ∼0–8 km depths is estimated to be ∼6.1%–8.6% from the seismic velocity reductions. Our results indicate that the Arxan magmatic system is still active at present. Plain Language Summary The detailed crustal structure and magmatic system beneath the Arxan volcanic field in NE China are still unclear due to the lack of a dense seismic network in the area. Local earthquakes associated with the volcanic activity in this area are all very small, so precise location of the seismic events is a challenge. We deployed a dense portable seismic network in the volcanic area to precisely locate 712 microearthquakes. Then we determine a detailed 3‐D seismic velocity model of the crust beneath the volcanic area. As a result, the spatial distribution and migration channel of magmatic reservoirs in the Arxan volcanic area are revealed for the first time. Key Points We precisely locate microearthquakes and study 3‐D Vp and Vs crustal structure beneath the Arxan volcanic area A microearthquake swarm occurred during 13–16 September 2020, reflecting magmatic activity of the Arxan volcanic group 12 Arxan volcanoes share the same magmatic system with a melt fraction of ∼6.1%–8.6%

The Editors-in-Chief have retracted this article [1] because it significantly overlaps with a number of previously published articles from different authors [2–4]. The author has not responded to any correspondence regarding this retraction.