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Steel scraps are renewable resources and indispensable iron resources for the iron and steel industry. In the context of carbon peaking and carbon neutrality, it is crucial to reconstruct the technology system for steel scrap recycling and utilization and innovate the management mode of steel scrap resources, so as to fundamentally crack the bottleneck of high-quality recycling and utilization of steel scraps for the green and low-carbon transformation of the iron and steel industry. This study analyzes the development status of the global steel scrap industry by comparison, predicts the changing trend of raw steel output and steel scrap resources in China, and proposes the possible existence of full steel scrap smelting in China around 2060. Moreover, the development directions of standardization, informatization, digitalization, and intelligentization of the steel scrap industry are summarized. The pressing problems and challenges regarding steel scrap recycling and utilization in China are systematically sorted out in terms of standards and institutional system, precise classification and recycling, material design based on extended producer responsibility (EPR), and digital identity parsing. On this basis, a new “4F5Z” pattern is innovatively proposed for the high-quality recycling and utilization of steel scrap resources, and its organizational framework and implementation strategy are clearly given. Specifically, the EPR system should be implemented in a coordinated manner toward a possible era of full steel scraps and from the aspects of the full life cycle, full production process, and full industrial chain (“4F”) of steel materials, thus to realize the sorted management, recycling, and reuse of steel scrap resources. Meanwhile, the digitalization, informatization, labelling, and networking of full production process management should be strengthened and gradually transition to the robotization of high-quality steel scrap dismantling and recycling (“5Z”). Furthermore, to provide a solid guarantee for the full implementation of the “4F5Z” pattern, we propose the following suggestions: (1) improving the system, technology, and management for EPR implementation in the iron and steel industry, (2) strengthening the construction of a standards system for the steel scrap industry, (3) strengthening the digital labelling and analysis of the entire industrial chain and the whole life cycle of iron and steel materials, and (4) reinforcing the sorted collection, recycling, and reuse of steel scraps in key industries.

Aiming at the problem of low applicability of differential interferometric synthetic aperture radar(DInSAR) and offset tracking(OT) technologies in the intersection area of small-scale and large-scale deformation in the edge and center of the subsidence basin, a method for extracting sub-regional deformation of mining subsidence by fusing cumulative DInSAR and adaptive OT is proposed. The method using the coherence coefficient and surface deformation gradient as thresholds to classify mining subsidence basins into three areas of different deformation scales. This paper takes 52303 working face mining subsidence basin of Daliuta Coal Mine as the study object, by combining with the surface measured data of the same period, the root mean square error(RMSE) of the medium scale deformation results by fusion method is less than 0.05 m, the RMSE of the study area is less than 0.11 m. It provides a new method for achieving fine monitoring of mining subsidence basins.

The close combat in air battle is still inevitable in future.The accurate and agile nose-pointing capability at high-angle-of-attack is still essential and significant for fighter to survive and gain air superiority.According to the high-angle-of-attack flight characteristics of fighter at home and abroad,the high-angle-of-attack aerodynamic,wind tunnel experiments method,aerodynamic modeling method,nonlinear flight dynamics analysis method,high-angle-of-attack control law design and flight test are reviewed.The research direction of high-angle-of-attack flight in the future is prospected.

Kwok Chuen Wong,1 Yan Edgar Sun,2 Shekhar Madhukar Kumta1 1Department of Orthopaedics and Traumatology, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China; 2New Territories, Hong Kong Special Administrative Region, People’s Republic of ChinaCorrespondence: Kwok Chuen Wong, Department of Orthopaedics and Traumatology, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China, Email skcwong@cuhk.edu.hkAbstract: In orthopaedic oncology, surgical planning and intraoperative execution errors may result in positive tumor resection margins that increase the risk of local recurrence and adversely affect patients’ survival. Computer navigation and 3D-printed resection guides have been reported to address surgical inaccuracy by replicating the surgical plans in complex cases. However, limitations include surgeons’ attention shift from the operative field to view the navigation monitor and expensive navigation facilities in computer navigation surgery. Practical concerns are lacking real-time visual feedback of preoperative images and the lead-time in manufacturing 3D-printed objects. Mixed Reality (MR) is a technology of merging real and virtual worlds to produce new environments with enhanced visualizations, where physical and digital objects coexist and allow users to interact with both in real-time. The unique MR features of enhanced medical images visualization and interaction with holograms allow surgeons real-time and on-demand medical information and remote assistance in their immediate working environment. Early application of MR technology has been reported in surgical procedures. Its role is unclear in orthopaedic oncology. This review aims to provide orthopaedic tumor surgeons with up-to-date knowledge of the emerging MR technology. The paper presents its essential features and clinical workflow, reviews the current literature and potential clinical applications, and discusses the limitations and future development in orthopaedic oncology. The emerging MR technology adds a new dimension to digital assistive tools with a more accessible and less costly alternative in orthopaedic oncology. The MR head-mounted display and hand-free control may achieve clinical point-of-care inside or outside the operating room and improve service efficiency and patient safety. However, lacking an accurate hologram-to-patient matching, an MR platform dedicated to orthopaedic oncology, and clinical results may hinder its wide adoption. Industry-academic partnerships are essential to advance the technology with its clinical role determined through future clinical studies.Keywords: mixed reality, augmented reality, virtual reality, cinematic rendering, orthopaedic oncology

Although diverse uranium (U) adsorbents have been explored, it is still a great challenge for high-efficient uranium extraction form seawater. Herein a wood-mimetic oriented porous Ti3C2Tx-MXene/gelatin hydrogel (MGH) has been explored through growing directional ice crystals cooled by liquid nitrogen and subsequently forming pores by freeze-dry (Ice-template) method, for ultrafast and high-efficient U-adsorption from seawater with great enhancement by both electric field and sunlight. Different from disperse Ti3C2Tx-MXene powder, this MGH not only can be easily utilized but also can own ultrahigh specific surface area for high-efficient U-adsorption. The U-adsorbing capacity of this MGH (10 mg) can reach 4.17 mg·g−1 after only 1 week in 100 kg of seawater, which is outstanding in existing adsorbents. Furthermore, on the positive pole of 0.4 V direct current source or under 1-sun irradiation, the U-adsorbing capacity of the MGH can increase by 57.11% and 13.57%, respectively. Most importantly, the U-adsorption of this hydrogel can be greatly enhanced by simultaneously using the above two methods, which can increase the U-adsorbing capacity by 79.95% reaching 7.51 mg·g−1. This work provides a new biomimetic porous MXene-based hydrogel for electric field/sunlight bi-enhanced high-efficient U-extraction from seawater, which will inspire new strategy to design novel U-adsorbents and systems.

Although metal–organic frameworks (MOFs) own excellent uranium adsorption capacity but are still difficult to conveniently extract uranium from seawater due to the discrete powder state. In this study, a new MOF-based macroporous membrane has been explored, which can high-efficiently extract uranium through continuously filtering seawater. Through modifying the UiO-66 with poly(amidoxime) (PAO), it can disperse well in a N,N-dimethylformamide solution of graphene oxide and cotton fibers. Then, the as-prepared super-hydrophilic MOF-based macroporous membrane can be fabricated after simple suction filtration. Compared with nonmodified MOFs, this UiO-66@PAO can be dispersed uniformly in the membrane because it can stabilize well in the solution, which have largely enhanced uranium adsorbing capacity owing to the modified PAO. Last but not least, different from powder MOFs, this UiO-66@PAO membrane provides the convenient and continuously uranium adsorbing process. As a consequence, the uranium extraction capacity of this membrane can reach 579 mg·g−1 in 32 ppm U-added simulated seawater for only 24 h. Most importantly, this UiO-66@PAO membrane (100 mg) can remove 80.6% uranyl ions from 5 L seawater after 50 filtering cycles. This study provides a universal method to design and fabricate a new MOF-based adsorbent for high-efficient uranium recovery from seawater.

Objective To establish and verify a postoperative delirium risk prediction model for elderly patients after individualized hip fracture surgery. Methods Clinical data of 393 elderly patients with hip fracture who underwent surgical treatment in the Department of Orthopedics, Xi'an Central Hospital from December 2016 to January 2021 were collected retrospectively in this study. The data from 333 patients during December 2016 and July 2020 were used as the model training set, and postoperative delirium was regarded as the research endpoint. Based on the model training set, uniuariate and multivariate logistic regression were adopted to screen out independent related factors of postoperative delirium. The model was established by regression coefficient, the nomogram was drawn combined with the rms package of R language, and the discrimination, calibration and clinical applicability of the model were tested. Bootstrap was used to repeatedly sample 1 000 times in the training set for internal verification of the model, and the data of 60 patients treated from August 2020 to January 2021 were employed as the verification set for external verification of the model. Results There were 393 elderly patients with hip fracture, including 333 cases in the training set, and 60 cases in the validation set. Univariate and multivariate logistic analysis showed that dementia, preoperative albumin level and intraoperative hypotension were independent related factors of postoperative delirium in elderly patients with hip fracture. The prediction model is obtained according to the relevant factors and regression coefficients: P=1/(1+e-Z), Z=1.396×dementia or not -0.275× preoperative albumin level +1.420×intraoperative hypotension or not +6.875. The cut-off value of the model in the training set is 0.235, and the specificity and sensitivity is 0.875 and 0.622, respectively. The cut-off value of the model in the validation set is 0.211, and the specificity and sensitivity is 0.800 and 0.800, respectively. The area under curve (AUC) of the receiver operating characteristic curve (ROC) in the training set and the validation set is 0.827 (95%CI: 0.762~0.892) and 0.836 (95%CI: 0.716~0.956) respectively. After 1 000 repeated sampling by bootstrap, the AUC of the internal verification of the model is 0.831. The slopes of the calibration curves of the training set and the validation set is 1 and 1.066, respectively. The P values of the Hosmer-Lemeshow goodness-of-fit test are 0.124 and 0.743, respectively. The clinical decision curve showed that the threshold probability interval of the maximum net benefit value of the postoperative delirium predicted by the model in the training set and the validation set was about 5%~90% and 3%~90% respectively. Conclusion Our established model can predict the risk of postoperative delirium in elderly patients after hip fracture surgery.

Dynamic covalent bond-based shape memory polymers (DCB-SMPs) are one of most important SMPs which have a wide potential application prospect. Different from common strong covalent bonds, DCBs own relatively weak bonding energy, similarly to the supramolecular interactions of noncovalent bonds, and can dynamically combine and dissociate these bonds. DCB-SMP solids, which can be designed to respond for different stimuli, can provide excellent self-healing, good reprocessability, and high mechanical performance, because DCBs can obtain dynamic cross-linking without sacrificing ultrahigh fixing rates. Furthermore, besides DCB-SMP solids, DCB-SMP hydrogels with responsiveness to various stimuli also have been developed recently, which have special biocompatible soft/wet states. Particularly, DCB-SMPs can be combined with emerging 3D-printing techniques to design various original shapes and subsequently complex shape recovery. This review has summarized recent research studies about SMPs based on various DCBs including DCB-SMP solids, DCB-SMP hydrogels, and the introduction of new 3D-printing techniques using them. Last but not least, the advantages/disadvantages of different DCB-SMPs have been analyzed via polymeric structures and the future development trends in this field have been predicted.

The public health harms caused by fine particulate matter (PM2.5) have become a global focus, with PM2.5 exposure recognized as a critical risk factor for global morbidity and mortality. Chronic inflammation is the common pathophysiological feature of respiratory diseases induced by PM2.5 and is the most critical cause of all these diseases. However, presently there is a lack of effective preventive and therapeutic approaches for inflammatory lung injuries caused by PM2.5 exposure. Baicalin is a herb-derived effective flavonoid compound with multiple health benefits. This study established a murine lung inflammatory injury model via inhalation of PM2.5 aerosols. The data showed that after baicalin intervention, lung injury pathological score of baicalin (4.16 ± 0.54, 3.33 ± 0.76, 4.00 ± 0.45) and claricid (3.00 ± 0.78) treatments were markedly lower than PM2.5-treated mice (6.17 ± 0.31), and pathological damage was alleviated. Compared to the PM2.5 group, the spleen and lung indexes in the baicalin and claricid groups were significantly reduced. The inflammatory cytokines of TNF-α, IL-18, and IL-1β in serum, alveolar lavage fluid, and lung tissue were significantly decreased in the baicalin and claricid groups. The expressions of inflammatory pathway-related genes and proteins HMGB1, NLRP3, ASC, and caspase-1 were up-regulated in the PM2.5 group. The expressions of these genes and proteins were significantly decreased following baicalin treatment. The lung function indicators showed that the MV (65.94 ± 8.19 mL), sRaw (1.79 ± 0.08 cm H2O.s), and FRC (0.52 ± 0.01 mL) in the PM2.5 group were higher than in the control and baicalin groups, and respiratory function was improved by baicalin. PM2.5 exposure markedly altered the bacterial composition at the genus level. The dominant flora relative abundances of uncultured_bacterium_f_Muribaculaceae, Streptococcus, and Lactobacillus, were decreased from the control group (9.20%, 8.53%, 6.21%) to PM2.5 group (6.26%, 5.49%, 4.77%), respectively. Following baicalin intervention, the relative abundances were 9.72%, 6.65%, and 3.57%, respectively. Therefore, baicalin could potentially prevent and improve mice lung inflammatory injury induced by PM2.5 exposure. Baicalin might provide a protective role by balancing oropharyngeal microbiota and affecting the expression of the HMGB1/Caspase1 pathway.

Under the innovation-driven development strategy, the improvement of the core competitiveness of enterprises demonstrates increasing dependence on the ability of technological innovation. In this article, data of A-share listed companies in Shanghai and Shenzhen stock markets from 2008 to 2018 were selected as research samples for the analysis of the influencing factors and mechanism of enterprise technological innovation from the dual perspectives of the external economic environment and internal management system based on the use of the fixed-effect model. The results show that government intervention significantly hinders enterprises' investment in resources for technological innovation, and less government intervention can improve the innovation investment of enterprises. The intervention of internal control fails to bring institutional advantages; rather, it aggravates the negative effect of government intervention on enterprise technological innovation. The research enriches the existing academic research results on government intervention, internal control quality, and enterprise technological innovation. The findings provide experience for accelerating the marketization process in China, enterprise governance, and improving the level of enterprise technological innovation.

[Objectives] In order to improve the anti-jamming ability and navigation stability of the unmanned sailing boats in the changeable and unknown environment and to realize accurate control of the heading of sailing boats,a fuzzy adaptive control method combined with the traditional PID technology is proposed.[Methods] The Nomoto motion mathematical model with three degrees of freedom was established,and the fuzzy rules and simulation controller were built with the Simulink modeling tool of Matlab,which could optimize and adjust the PID control parameters in real time and online. In the case of different speeds and random perturbations,a comparison with the traditional PID control was made to analyze the influence of different control methods on the heading and validate it by experiments.[Results] The results show that the fuzzy PID method has good adaptive ability and robustness to control the heading of small unmanned sailing boats.[Conclusions] The study of this paper can provides references for heading control of unmanned sailing boats.

The structure of a complicated fixture is usually designed improperly using common methods,which are usually based on experience and formulas. Modal analysis of the fixture was performed based on the 3D finite element model,thus its natural frequencies and vibration modes were obtained to optimize the design. The natural frequencies、energy magnifying factor、scope of orthogonal motion and differences in vibration response among fixed points of the optimized fixture were analyzed to make sure the design meet the fixture design standardization. The result is verified through the vibration test and shows good performance of the fixture in vibration test.

[This corrects the article DOI: 10.1371/journal.pone.0081393.].

A better understanding of embryo development would provide insights into seed quality and subsequent germination events in the interspecific hybridization of Cymbidium faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’. At the mature stage, 26.1% of the ovules were abnormal. Most of the hybrid embryos could develop normally. Abortions mainly occurred at the zygote (9.5%) and 2-4-celled embryo (15.1%) stages. No germination was observed at 90 and 105 days after pollination (DAP), when the embryo was at the early globular stage, with abundant organelles but no storage materials. During 110-130 DAP, the globular embryo was formed and the starch grains began to accumulate in plastids. The hybrid seeds collected at 120 DAP showed initiation of germination. Germination significantly increased at 135 DAP and was maximal at 150 DAP, during which period the hybrid embryos developed into the late globular stage. The storage materials, i.e. lipid and protein bodies, began to accumulate and the filamentary structures derived from suspensor cells still persisted. After the seeds matured (160 DAP), the germination percentage declined sharply. Safranin staining revealed that the outer seed coat was totally cuticularized and the inner seed coat appeared as a cuticle layer enclosing the embryo proper tightly, which may be the main factor inhibiting the subsequent germination of hybrid seeds. In conclusion, 150 DAP should be the opportune time for the in vitro germination of C. faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’ hybrid seeds.

The neutron-rich nuclei 136Sn and 132Cd have been studied in the purpose of nuclear structure for the nuclei beyond the doubly-magic nucleus 132Sn. The 2+1 → 0+ gs transitions were identified for these two nuclei using in-beam γ-ray spectroscopy in coincidence with one- and two-proton removal reactions, respectively, at the RIKEN Radioactive Isotope Beam Factory. The 2+ 1 state in 136Sn is found to be similar to that for 134Sn indicating the seniority scheme may also hold for the heavy tin isotopes beyond N = 82. For 132Cd, the 2+ 1 state provides the first spectroscopic information in the even-even nuclei locating in the region “southeast” of 132Sn and the result is discussed in terms of proton-neutron configuration mixing. In both these two nuclei, it was found that the valence neutrons play an essential role in their low-lying excitations.