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Tibial plafond fractures, especially the AO/OTA type C3 ones that take place in young patients with excessive facet fragmentation and cartilage loss that preclude anatomical reduction and effective internal fixation, are devastating situations that often subject to primary arthrodesis. The aim of the current study is to introduce a joint preserving technique by using osteochondral autograft to treat such difficult cases and to evaluate its short-term outcome.A total of 11 patients suffering AO-OTA type C3 tibial plafond fractures with irreparable area treated with osteochondral autograft and ORIF, with an average follow-up period of 34 months, were analyzed. Visual analogue scale (VAS), short-form 36 (SF-36), American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, and ankle range of motion (ROM) were assessed for functional outcome evaluation. The weight-bearing AP and lateral radiograph, as well as CT reconstructive images were examined to evaluate bony union and the occurrence of post-traumatic arthritis.At the final follow-up, the mean VAS scale was 2.2. The mean AOFAS and SF-36 scores were 86.3 and 84.5 respectively. Among all the included patients, 8 achieved both AOFAS and SF-36 scores above 80. The average ankle range of motion was 29.9°. No infection, compartment syndrome, post-traumatic arthrosis or donor site pain was noted in the current study. No patient received secondary ankle arthrodesis at the end of the follow-up.Although primary ankle arthrodesis is an effective method, routine ankle arthrodesis should be carried out with second thoughts in patients, especially patients with relatively young age, suffering AO-OTA type C3 tibial plafond fractures with irreducible area. On the other hand, osteochondral autograft transplantation may provide a chance to relieve pain without sacrificing the joint.

Spurs have played an important role in the radiation of the genus Aquilegia, but little is known about how the spurless state arose in A. ecalcarata. Here we aim to characterize the genetic divergence within A. ecalcarata and gain insights into the origin of this species. A total of 19 populations from A. ecalcarata and 23 populations from three of its closest relatives (Aquilegia kansuensis, Aquilegia rockii and Aquilegia yabeana) were sampled in this study. We sequenced fifteen nuclear gene fragments across the genome and three chloroplast loci to conduct phylogenetic, PCoA and STRUCTURE analyses. Our analyses indicate that A. ecalcarata may not be monophyletic and can be divided into two distinct lineages (A. ecalcarata I and A. ecalcarata II). A. ecalcarata I is genetically close to A. kansuensis, whereas A. ecalcarata II is close to A. rockii. Isolation-with-migration analysis suggested that historical gene flow was low between A. ecalcarata I and A. rockii, as well as between A. ecalcarata II and A. kansuensis. The two distinct lineages of A. ecalcarata show significant divergence in 13 floral traits and also have distinct distributions. In addition, both A. ecalcarata I and II are adapted to a stony environment that differs from that of their closest relatives, indicating a habitat shift may have driven new adaptations. Our findings enrich the understanding of how floral evolution contributes to species diversification.

Phagocytosis performed by a macrophage involves complex membrane trafficking and reorganization among various membranous cellular structures including phagosomes and vesicles derived from the phagosomes known as phagosome-derived vesicles. The present work reports on development of a technique that allows to specifically label the phagosome-derived vesicles in macrophages with a membrane dye. The technique is based on the use of microfabricated microparticles that are made of a thermosensitive nonbiodegradable polymer poly(N-isopropylacrylamide) (PNIPAM) or its derivative and contain a membrane dye 1,1′-dialkyl-3,3,3′,3′-tetramethylindodicarbocyanine (DiI). The microparticles can be phagocytosed by RAW264.7 macrophages into their phagosomes, resulting in formation of intracellular DiI-positive vesicles derived from the phagosomes. The DiI-positive vesicles are motile and acidic; can be stained by fluorescently labelled dextran added in the culture medium; and can accumulate around new phagosomes, indicating that they possess properties of lysosomes. This technique is also applicable to another membrane dye 3,3'-dioctadecyloxacarbocyanine (DiO) and holds great potential to be useful for advancing our understanding of phagocytosis. STATEMENT OF SIGNIFICANCE: Phagocytosis performed by macrophages is a cellular process of great importance to various applications of biomaterials such as drug delivery and medical implantation. This work reports on a technique for characterizing phagocytosis based on the use of poly(N-isopropylacrylamide), which is a major biomaterial with numerous applications. This technique is the first of its kind and has generated an original finding about phagocytosis. In addition to drug delivery and medical implantation, phagocytosis plays critical roles in diseases, injuries and vaccination. This work could thus attract immediate and widespread interests in the field of biomaterials science and engineering.

The fault propagation of multistate systems (MSSs) with various operational modes is a critical factor affecting the reliability and safety of systems. However, traditional methods have difficulty describing the influence of function transitions and multiple faults of components on fault propagation, and are inapplicable for accurately evaluating the dynamic reliability of MSSs. To solve these issues, an agent-based method is developed to evaluate the dynamic reliability of MSSs. This study proposes a reliability modeling framework that consists of a management agent and several system agents. Combined with different agents, two types of models are established to describe the logical relationships among components. Moreover, Monte Carlo simulation is used to evaluate the dynamic reliability of MSSs, and a visual failure paths analysis method is proposed to inhibit potential risk. The LH4-1 horizontal Christmas tree is used to verify the effectiveness of proposed method. Under the designed working condition, the dynamic reliability curve of system with three operational modes and the visual failure paths including 15-node are obtained. By comparing the influence of failure rates, it is found that the production choke valve, flowlines, tree cap and MEG chemical control valve have a great impact on the system reliability.

This paper develops a novel optimization method oriented to the resilience of multiple Unmanned Aerial Vehicle (multi-UAV) formations to achieve rapid and accurate reconfiguration under random attacks. First, a resilience metric is applied to reflect the effect and rapidity of multi-UAV formation resisting random attacks. Second, an optimization model based on a parameter optimization problem to maximize the system resilience is established. Third, an Adaptive Learning-based Pigeon-Inspired Optimization (ALPIO) algorithm is designed to optimize the resilience value. Finally, typical formation topologies with six UAVs are investigated as a case study to verify the proposed approach. The experimental results indicate that the proposed scheme can achieve resilience optimization for a multi-UAV formation reconfiguration by increasing the system resilience values to 97.53% and 81.4% after random attacks.

Dark fermentation (DF) is a promising technology for biohydrogen production. Low efficiency of biohydrogen production is a bottleneck of the scale-up prospects for DF. Additives have been extensively studied to improve the biohydrogen production efficiency. Among of them, iron-based additives present a promising application potential due to their demonstrated significant enhancement of DF efficiency and among the low-cost bioactive agents. However, current reviews mainly examined the effects of nano-materials on DF and an in-depth analysis of enhancing mechanisms with addition of iron-based additives in DF is still lacking. To this end, this article comprehensively reviewed and evaluated the effects of iron-based additives on DF. Further, the potential mechanisms, including altering metabolic pathways, improving activities of microbes and enzymes, promoting electron delivery, and enriching hydrogen-producing bacteria, were discussed. Lastly, prospects and challenges of iron-based additives for subsequent research and large-scale application for DF were summarized.

To invest the dynamic response of submerged floating tunnel (SFT) under shock-vehicle load action, this paper develops a SFT math model considering the coupled vibration of the vehicle, tether, and the flexible boundary tube by the Lagrange equation. The four-order Runge-Kutta method is used to solve the vibration differential equations. The model reliability is verified by using the existing theoretical model. The influence law of the tube end stiffness, impact load, vehicle load on the SFT dynamic response is discussed by combine with the data of the proposed SFT. The result show: Compared to existing theoretical models, the coupled SFT model can consider different boundary conditions of tunnel tube and reflect the tube dynamic response more accurately. The system's displacement significantly decreases with the tube end stiffness increase, but the effect is no longer apparent when it decreases to a specific value; The tension ratio between the mid-span tether and the edge tether increases significantly with the tube end stiffness increase. The system's displacement increases significantly with the impact momentum increases, and the vehicle's displacement increment is larger than the tube. The system's displacement increases linearly as the vehicle mass increase; The vehicle speed has a slight effect on the tube displacement, but it has a nonlinear effect on vehicle displacement.