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Fullerene-based amphiphiles are new types of monomers that form self-assemblies with profound applications. The conical fullerene amphiphiles (CFAs) have attracted attention for their uniquely self-assembled structures and have opened up a new field for amphiphile research. The CFAs and CFAs with different substances embedded in cavities are designed and their self-assembly behaviors are investigated using molecular dynamics (MD) simulations. The surface and internal structures of the micelles are analyzed from various perspectives, including micelle size, shape, and solvent-accessible surface area (SASA). The systems studied are all oblate micelles. In comparison, embedding Cl− or embedding Na+ in the cavities results in larger micelles and a larger deviation from the spherical shape. Two typical configurations of fullerene surfactant micelles, quadrilateral plane and tetrahedral structure, are presented. The dipole moments of the fullerene molecules are also calculated, and the results show that the embedded negatively charged Cl− leads to a decrease in the polarity of the pure fullerene molecules, while the embedded positively charged Na+ leads to an increase. [ABSTRACT FROM AUTHOR]

Soft robotics have found their tremendous application prospects in wearable robots due to the inherent compliance of soft materials when interacting with human bodies. However, the limited load-bearing and output capabilities impeded their application in real world. Variable stiffness design contributes to tackling this problem by enhancing the overall structural rigidity. Nevertheless, most of current jamming-based variable stiffness structures realize their stiffness enhancement by squeezing discrete rigid elements, resulting in the loss of structural compliance in the high stiffness state, which could significantly reduce the deformability and even injure the individuals when utilized in wearable robots. In this paper, we propose a muscle-inspired stiffness-continuously-adjustable flexible fiber jamming (FFJ) structure for soft wearable robots. The FFJ structure can achieve continuous stiffness-variation by controlling the fiber overlapping length, which maintains stretchability even in the high stiffness state. We provide a theoretical model to analyze the mechanical performance of the proposed FFJ structure with different design parameters, and verify the model experimentally. The preliminary results show that we achieved 9 times of stiffness enhancement of the proposed FFJ structure by controlling the vacuum pressure, and the maximum tensile stiffness is 4.1 N mm−1. We further demonstrated the effectiveness of the proposed FFJ structure on wearable robots in three different working scenarios: active finger rehabilitation, active elbow rehabilitation, and passive trunk support. The results show that the FFJ structure was able to provide controllable impedance force for active finger/elbow rehabilitation, and help support the human body during long-term labor. This work broadens the frontiers of soft wearable robots and leads a way to the future design of soft and strong robots and devices. [ABSTRACT FROM AUTHOR]

Despite impressive advances achieved in poly(3‐alkylthiophene)s (P3ATs) and P3AT‐based block copolymers (BCPs), the investigation into their ortho‐connected systems, poly(5‐alkylthiophene)s (P5ATs) and P5AT‐based BCPs is rather limited. Moreover, the aggregation behavior of P5ATs and their BCPs remains largely less understood. Herein, we report, for the first time, the judicious design and synthesis of a family of poly(5‐butylthiophene)‐block‐poly(5‐hexylthiophene) (P5BT‐b‐P5HT) BCPs with adjustable block ratios and reveal the effects of block ratios and thermal annealing process on their aggregated structures. Moreover, the optical properties of P5BT‐b‐P5HT BCPs have been investigated, which differs greatly from P3ATs. Overall, this work offers valuable insight into the aggregation and optical properties of P5AT‐based BCPs, strengthening our fundamental understanding of ortho‐connected P5AT systems. [ABSTRACT FROM AUTHOR]

The threat of microplastics to marine animals and habitats is increasing, which may affect sea turtle nesting grounds. The Qilianyu Islands are the largest remaining green turtle (Chelonia mydas) nesting grounds in China. Despite being far from the mainland, microplastic pollution cannot be ignored. In this study, the level of microplastic pollution in surface sediments from three different zones, namely, the bottom, intertidal, and supratidal zone, was investigated on North Island, Qilianyu Islands. The results showed that the abundance of microplastics in the supratidal zone was significantly higher than that in the bottom zone and intertidal zone (r = 3.65, p = 0.011), with the highest average abundance of microplastics located on the southwest coast of North Island. In the bottom zone, only plastic blocks (88%) and fibers (12%) were found. The main types of microplastics in the intertidal and supratidal zones were plastic blocks (48%) and foam (42%), with polyethylene (PE) (40%) and polystyrene (PS) (34%) being the predominant components. These types and components of microplastics differed from those in the surrounding seawater, but corresponding types and components were found in the plastic debris on the beach. Meanwhile, it was also observed that there were multiple instances of fragmented plastic on the beach. Thus, we suggest that the microplastics on the beach in North Island were mainly derived from the fragmentation of microplastic debris, indicating secondary microplastics. It is recommended to further strengthen the regular cleaning of plastic debris on the beach, especially the removal of small plastic debris, in order to reduce the pollution from secondary microplastics generated by the fragmentation of beach plastic debris and to better protect China's most important sea turtle nesting site in the South China Sea. [ABSTRACT FROM AUTHOR]

Betaine is a kind of zwitterionic surfactant with both positive and negative charge groups on the polar head, showing good surface activity and aggregation behaviors. The interfacial adsorption, structures and properties of n-dodecyl betaine (NDB) at different surface coverages at the air–water interface are studied through molecular dynamics (MD) simulations. Interactions between the polar heads and water molecules, the distribution of water molecules around polar heads, the tilt angle of the NDB molecule, polar head and tail chain with respect to the surface normal, the conformations and lengths of the tail chain, and the interfacial thickness of the NDB monolayer are analyzed. The change of surface coverage hardly affects the locations and spatial distributions of the water molecules around the polar heads. As more NDB molecules are adsorbed at the air–water interface, the number of hydrogen bonds between polar heads and water molecules slightly decreases, while the lifetimes of hydrogen bonds become larger. With the increase in surface coverage, less gauche defects along the alkyl chain and longer NDB chain are obtained. The thickness of the NDB monolayer also increases. At large surface coverages, tilted angles of the polar head, tail chain and whole NDB molecule show little change with the increase in surface area. Surface coverages can change the tendency of polar heads and the tail chain for the surface normal. [ABSTRACT FROM AUTHOR]

The aggregation structure of Triton X (TX) amphiphilic molecules in aqueous solution plays an important role in determining the various properties and applications of surfactant solutions. In this paper, the properties of micelles formed by TX-5, TX-114, and TX-100 molecules with different poly(ethylene oxide) (PEO) chain lengths in TX series of nonionic surfactants were studied via molecular dynamics (MD) simulation. The structural characteristics of three micelles were analyzed at the molecular level, including the shape and size of micelles, the solvent accessible surface area, the radial distribution function, the micelle configuration, and the hydration numbers. With the increase of PEO chain length, the micelle size and solvent accessible surface area also increase. The distribution probability of the polar head oxygen atoms on the surface of the TX-100 micelle is higher than that in the TX-5 or TX-114 micelle. In particular, the tail quaternary carbon atoms in the hydrophobic region are mainly located at the micelle exterior. For TX-5, TX-114, and TX-100 micelles, the interactions between micelles and water molecules are also quite different. These structures and comparisons at the molecular level contribute to the further understanding of the aggregation and applications of TX series surfactants. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the efficacy of surgery combined with triamcinolone acetonide injection in managing the difficult problem of keloid formation after syndactyly release. Twenty-two patients with keloid formation after syndactyly release were retrospectively reviewed. They were divided into a simple surgery group and a surgery plus injection group. Complications, web quality, scar score and satisfaction were assessed and compared. In the surgery plus injection group, three patients (3/13) experienced recurrence and ten webs were good, whereas in the simple surgery group, seven patients (7/9) experienced recurrence and five webs were poor. The mean Vancouver Scar Scale score was significantly lower (4.3 versus 7.8) and the mean Faces Questionnaire satisfaction score was higher (4.2 versus 2.6) in the surgery plus injection group. Combining surgical excision with early and repeated intralesional injection can achieve better results with low recurrence rate and side effects. Level of evidence: IV [ABSTRACT FROM AUTHOR]

Recent achievements in the field of electronic skin (e-skin) have provided promising technology for service robots. However, the development of a bionic perception system that exhibits superior performance in terms of safety and interaction quality remains a challenge. Here, we demonstrate a biomimetic soft e-skin that is composed of an array of capacitors and air pouches. It is a single platform that shows dual-mode sensing capabilities of tactile sensing and proximity perception. We optimized the shape and area of the electrode via simulation of the approach of a robot to an object. Moreover, the compliance and temperature of the e-skin can be actively adjusted by tuning the pressure and heat of the air inside the pouches. The e-skin provided dual-mode sensing feedback and soft touch for humanoid service robots, for example, when a robot hugged a man, which illustrated the potential of this e-skin for applications in human–robot interactions. [ABSTRACT FROM AUTHOR]

Brachydactyly Type D is a congenital condition of the thumb in which there is a short and broad thumbnail. Although the thumb function is often unaffected, some patients seek surgery for cosmetic improvement. This study aimed to describe our method of distraction lengthening to correct nail deformity in brachydactyly Type D. A total of 163 thumbs in 95 patients underwent this surgery between 2018 and 2021.The mean thumbnail length improved from 9 mm to 15 mm, with a mean percentage increase of 62%. The ratio of nail length to width changed from 0.6 to 1.1, which was equal to normal. The mean increased fingernail length/width ratio was 0.5, with a percentage change of 78%. No obvious surgical scar was observed. The thumb function was not significantly affected. We conclude that aesthetic correction of short nail deformity in brachydactyly Type D can be achieved by distraction lengthening with high satisfaction and without functional impairment. Level of evidence: IV [ABSTRACT FROM AUTHOR]

Objective. The objective of this study is to explore the effect of kartogenin (KGN-)-pretreated adipose-derived stem cell-derived exosomes (ADSC-EXOs) on the chondrogenic differentiation ability of ADSCs. Methods. Adipose-derived stem cells (ADSCs) were treated with different doses of KGN, and exosomes (EXOs) were extracted. EXOs were then identified using an electron microscope (EM), nanoparticle tracking analyzer, nanoparticle tracking analysis software, and exosomal protein markers. EXOs were labeled with the fluorescent dye PKH67 and their uptake by cells was evaluated. A cell counting kit-8 (CCK-8) assay, flow cytometry, clonogenic assay, and a cell scratch assay were used to detect the abilities of proliferation, apoptosis, clone formation, and migration of ADSCs, respectively. Subsequently, Alcian blue staining and toluidine blue staining were used to detect the chondrogenic differentiation ability of ADSCs in each group. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot (WB) techniques were used to detect the expression of chondrogenic differentiation-related genes. Results. In this study, ADSCs and KGN-induced ADSC-EXOs were successfully extracted and isolated. EXOs and ADSCs coculturing results showed that KGN-induced ADSC-EXOs can significantly promote proliferation, clone formation, migration, and chondrogenic differentiation of ADSCs and inhibit apoptosis. In addition, KGN-induced ADSC-EXOs can increase the expression of chondrogenic-related genes in ADSCs (Aggrecan, Collagen III, Collagen II, and SOX9), and can significantly decrease the expression of chondrolysis-related genes (MMP-3, ADAMTS4, and ADAMTS5). Conclusion. KGN-induced ADSC-EXOs can enhance the chondrogenic differentiation ability of ADSCs by promoting cell proliferation and migration while inhibiting cell apoptosis. KGN treatment can also increase the expression of chondrogenic differentiation-related genes and decrease the expression of chondrolysis-related genes. These results provide a new approach to cartilage repair and regeneration. [ABSTRACT FROM AUTHOR]

W‐plasty is a very popular scar excisional revision technique. The core of the technique is to break up the scar margins into small triangular components, so as to cause light scattering and make the scar less noticeable. However, due to skin tension, facial incision scars tend to spread. Applying W‐plasty alone cannot achieve the ideal repair effect of facial scars. In this study, we proposed a scar revision technique combined W‐plasty with continuous tension‐reduction (CTR) technique to improve the appearance of facial scars. Sixty patients with facial scar were comprised in this retrospective study. Scars were assessed independently using the scar scale before and at 12‐month follow‐up. Clinical results showed a significant difference in scar appearance between different groups at 12‐month follow‐up. Vancouver scar scale (VSS), visual analogue scale (VAS) scores, and patient satisfaction were significant better in W‐plasty and CTR than other groups at 12‐month follow‐up. No severe complications were reported. The application of the tension offloading device provides an environment where the tension is continuously reduced, which could greatly decrease tension on the surgical incision. Combined with W‐plasty, this technique could significantly improve the scar's aesthetic appearance. [ABSTRACT FROM AUTHOR]

Tendon development requires the coordinated interaction of muscles and tendons. Muscle-derived cells (MDCs), a mixed cell population containing both myogenic and fibroblastic cell subsets, have been found to be ideal seed cells for tendon regeneration. However, the necessity of these cell types for tendon regeneration has not yet been tested. In this study, we aim to explore the possible synergistic effects of myogenic cells and fibroblasts in engineered tendon regeneration. MDCs were separated into rapidly adhering cell (RAC; fibroblasts) and slowly adhering cell (SAC; myogenic cells) populations. Myogenic- and tenogenic-related molecules were analyzed by immunofluorescent staining, RT-PCR and real-time PCR. The proliferative abilities of MDCs, RACs and SACs were also evaluated. Cell-scaffold constructs were implanted into nude mice, and subsequently evaluated for their histologic, ultrastructure, gene expression, and biomechanical characteristics. MDCs have better proliferative activity than RAC and SAC population. RACs could express higher levels of tenogenic-related molecules tenomodulin (TNMD) and scleraxis (SCX) than SACs. Whereas SACs only expressed myogenic-related molecules MyoD. In contrast to the tendons engineered using RACs and SACs, the tendons engineered using MDCs exhibited a relatively more mature and well-organized tissue structure and ultrastructure as well as better mechanical properties. Fibroblasts in muscle may be the primary cell population involved in tendon regeneration and that myogenic cells are an important component of the niche and control the fibroblast activity during tendon regeneration. The synergistic effects between fibroblasts and myogenic cells significantly contribute to efficient and effective regeneration of engineered tendons. [ABSTRACT FROM AUTHOR]

Cutaneous wound healing in diabetes is impaired and would develop into nonhealing ulcerations. However, the molecular mechanism underlying the wound-healing process remains largely obscure. Here, we found that cutaneous PDGFRα+ fibroblast-expressing lncRNA-H19 (lncH19) accelerates the wound-healing process via promoting dermal fibroblast proliferation and macrophage infiltration in injured skin. PDGFRα+ cell-derived lncH19, which is lower in contents in the wound-healing cutaneous tissue of patients and mice with type 2 diabetes, is required for wound healing through promoting proliferative capacity of dermis fibroblasts as well as macrophage recruitments. Mechanistically, lncH19 relieves the cell cycle arrest of fibroblasts and increases macrophage infiltration in injured tissues via inhibiting p53 activity and GDF15 releasement. Furthermore, exosomes derived from adipocyte progenitor cells efficiently restore the impaired diabetic wound healing via delivering lncH19 to injured tissue. Therefore, our study reveals a new role for lncRNA in regulating cutaneous tissue repair and provides a novel promising insight for developing clinical treatment of diabetes. [ABSTRACT FROM AUTHOR]

Cartilage tissue engineering is a promising option for repairing cartilage defects, although harvesting a large number of seeding cells remains a major challenge. Cartilage stem/progenitor cells (CSPCs) seem to be a promising cell source. Hypoxic extracellular vesicles (EVs) may play a major role in cell-cell and tissue-tissue communication. In the current study, we aimed to evaluate the effect of hypoxic adipose-derived stem cells (ADSCs)-derived EVs on CSPCs proliferation and differentiation. The characteristics of ADSCs-derived EVs were identified, and proliferation, migration, and cartilage-related gene expression of CSPCs were measured with or without the presence of hypoxic ADSCs-derived EVs. SEM, histological staining, biochemical and biomechanical analysis was performed to evaluate the effect of hypoxic ADSCs-derived EVs on CSPCs in alginate hydrogel culture. The results indicated that the majority of ADSC-derived EVs exhibited a round-shaped or cup-shaped morphology with a diameter of 40–1000 nm and expressed CD9, CD63, and CD81. CSPCs migration and proliferation were enhanced by hypoxic ADSCs-derived EVs, which also increased the expression of cartilage-related genes. The hypoxic ADSCs-derived EVs induce CSPCs to produce significantly more cartilage matrix and proteoglycan. In conclusion, hypoxic ADSCs-derived EVs improved the proliferation and chondrogenic differentiation of CSPCs for cartilage tissue engineering. [ABSTRACT FROM AUTHOR]

In order to solve the problems of botnets' strong concealment and difficulty in identification, and improve the detection accuracy of botnets, a botnet detection method based on generative adversarial networks was proposed. By reorganizing the data packets in the botnet traffic into streams, the traffic statistics characteristics in the time dimension and the traffic image characteristics in the space dimension were extracted respectively. Then with the botnet traffic feature generation algorithm based on generative adversarial network, botnet feature samples were produced in the two dimensions. Finally combined with the application of deep learning in botnet detection scenarios, a botnet detection model based on DCGAN and a botnet detection model based on BiLSTM-GAN were proposed. Experiments show that the proposed model improves the botnet detection ability and generalization ability. [ABSTRACT FROM AUTHOR]

Hand burns are frequently seen in children, often resulting in digital flexion contractures. Traditional split‐thickness or full‐thickness skin grafts leave notably different skin texture and hyperpigmentation. The purpose of this study was to describe our operation for treating digital flexion contractures with full‐thickness plantar skin grafts, and to evaluate the appearance and function outcomes. Hematoxylin and eosin staining, Masson trichrome staining and Melan A (marker of melanocyte) staining were used to evaluate palmar skin, plantar skin, groin skin and burn scars. Full‐thickness plantar skin grafts were performed between 2008 and 2015 in 24 hand burn patients with digital flexion contracture. The average age at the time of surgery was 39.3 months and the average follow‐up period was 5.5 years. The functional and cosmetic results were assessed. Plantar skin shared similar attributes with palmar skin histologically. Both plantar skin and palmar skin did not express melan A. All of the skin grafts survived well without hematoma, infection and necrosis. The grafts resembled the adjacent normal skin in regards to appearance and texture. The average TAM (total active movement) degree for the fingers was improved from 152.3° to 238.5°. The average VSS (Vancouver Scar Scale) score decreased dramatically from 10.4 to 1.1. Twenty one of twenty four patients (21/24, 87.5%) were very satisfied with function and appearance, and three in twenty four (3/24, 12.5%) were somewhat satisfied. This study indicates that full‐thickness plantar skin grafts can achieve a satisfactory appearance and good function for hand burn child patients with digital flexion contractures. [ABSTRACT FROM AUTHOR]

Background: Macrodactyly is a congenital malformation characterized by aggressive overgrowth of multiple tissues, including subcutaneous fat, nerves, and bones in digits or limbs. In type II macrodactyly, the peripheral nerve is enlarged; however, the morphological and functional characteristics of the affected peripheral nerves have rarely been evaluated. Methods: In this research, six macrodactyly patients and three polydactyly patients (control) were studied. Pre-operative sensory nerve action potential and intra-operative nerve action potential tests were performed. The microstructure and ultrastructure of the enlarged nerves were observed and neurofilament (NF) expression was evaluated using immunofluorescent staining. Results: Axon impairment of the digital nerves originating from the median nerve (MN) was observed. A compensatory reinnervation from the ulnar nerve (UN) was found in two of the six patients, and significant morphological changes were observed in the enlarged nerve. The myelinated nerve fibers decreased, the lamellar structure of the myelin sheath changed, and the density of the NFs of the unmyelinated fibers decreased. There was aberrant distribution of NFs in the macrodactylous nerve tissues. In patients with compensatory UN reinnervation, the number of myelinated and unmyelinated fibers increased to normal levels; however, the diameter of the myelinated fibers apparently decreased. Conclusions: The morphology and function of the macrodactylous enlarged nerve was impaired in type II macrodactyly patients; however, the unaffected UN partially compensated for the lost function of the affected MN under specific situations. Electrophysiological tests should be performed to determine the function of the affected nerve and surgical treatment for type II macrodactyly could be refined. [ABSTRACT FROM AUTHOR]