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Due to thrombosis and intimal hyperplasia, small-diameter vascular grafts have poor long-term patency. A combination strategy based on nitric oxide (NO) and anticoagulants has the potential to address those issues. In this study, poly(ethylene terephthalate) (PET) mats were prepared by electrospinning and coated with tannic acid (TA)/copper ion complexes. The chelated copper ions endowed the mats with sustained NO generation by catalytic decomposition of endogenous S-nitrosothiol. Subsequently, zwitterionic carboxybetaine acrylate (CBA) and argatroban (AG) were immobilized on the mats. The introduced AG and CBA had synergistic effects on the improvement of blood compatibility, resulting in reduced platelet adhesion and prolonged blood clotting time. The biocomposite mats selectively promoted the proliferation and migration of human umbilical vein endothelial cells while inhibiting the proliferation and migration of human umbilical arterial smooth muscle cells under physiological conditions. In addition, the prepared mats exhibited antibacterial activity against Escherichia coliand Staphylococcus aureus. Collectively, the prepared mats hold great promise as artificial small-diameter vascular grafts.

This study investigated the impact of coronavirus disease 2019 (COVID‐19) from the perspectives of dental residents in Wuhan, the former COVID‐19 epicenter of China. A survey form was sent to 424 residents in the School of Stomatology, Wuhan University (WHUSS) in September 2020. The form included 23 questions on demographics, study situation of residents during the COVID‐19 outbreak, effect of COVID‐19 on graduates, and status of residents who returned to clinic training. A total of 361 (85%) survey forms were collected. Over 70% of respondents felt anxious during Wuhan lockdown. Most respondents continued studying (94%) mainly through free online resources (79%). The majority reported improvement in didactic knowledge (80%), but the respondents’ perceptions of their clinical skills, especially those in Wuhan, did not change (41%) or worsened (40%) (p< 0.05). Most graduates (88%) reported having found jobs or continued study. Among the 209 responders who returned to clinical training, 52% felt no concern about COVID‐19 infection, 89% thought they were equipped with adequate personal protective equipment (PPE), and 57% indicated that they received sufficient knowledge for preventing COVID‐19 in clinic. Most respondents agreed that the way to gain the knowledge for preventing COVID‐19 in clinic was training at dental school (93%). Although online study has been appreciated by residents, concern about clinical skill learning in the COVID‐19 hardest‐hit area has arisen. Most graduates felt that the impact of COVID‐19 on their immediate postgraduation career was limited. Teaching about infection control in dental schools seemed effective to develop a positive attitude for residents after they returned to clinical training.

Recent studies have demonstrated regional differences in marine ecosystem C:N:P with implications for carbon and nutrient cycles. Due to strong co-variance, temperature and nutrient stress explain variability in C:N:P equally well. A reductionistic approach can link changes in individual environmental drivers with changes in biochemical traits and cell C:N:P. Thus, we quantified effects of temperature and nutrient stress on Synechococcuschemistry using laboratory chemostats, chemical analyses, and data-independent acquisition mass spectrometry proteomics. Nutrient supply accounted for most C:N:Pcellvariability and induced tradeoffs between nutrient acquisition and ribosomal proteins. High temperature prompted heat-shock, whereas thermal effects via the “translation-compensation hypothesis” were only seen under P-stress. A Nonparametric Bayesian Local Clustering algorithm suggested that changes in lipopolysaccharides, peptidoglycans, and C-rich compatible solutes may also contribute to C:N:P regulation. Physiological responses match field-based trends in ecosystem stoichiometry and suggest a hierarchical environmental regulation of current and future ocean C:N:P.

Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments, in which a wearable hand exoskeleton is one of the key devices. Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object. This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain. Each finger has an independent closed-loop kinematic chain, and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction. The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time. Based on the finger exoskeleton, an adaptive hand exoskeleton is consequently developed. In addition, the hand exoskeleton is tested in a master–slave system. The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints, and the slave hand can follow the motions of each human finger. The accuracy and the real-time capability of the force reproduction are validated. The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand, thus, enabling the teleoperation system to complete complex dexterous manipulation tasks.