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Learning calligraphy writing skills in robots is regarded as a sophisticated task. Current robotic researchers have proposed many methods to implement various robotic calligraphy systems. However, several limitations of these methods, such as high computational costs and few diversities of generated results constrain the development of calligraphy robots. This article proposes a robotic writing framework based on a robotic hand–eye coordination method to solve these limitations. Inspired by the internal model control (IMC) system, a vision-motor network and a motor-vision network are built to simulate the direct and reverse models, respectively, in the IMC system of a robotic manipulator. The vision-motor network works as an action generator to convert image inputs to robotic actions, and the motor-vision network assists in the training of the vision-motor network. Thus, a pretraining of the motor-vision network is established by random writing movements of a robotic manipulator. Experimental results demonstrate that the proposed method can successfully write strokes of Chinese characters by inputting target stroke images. Although the proposed method is applied to robotic calligraphy, the underpinning research is readily applicable to many other applications, such as human–robot motion mimicking.

Nitric oxide (NO) is drawing widespread attention in treating pancreatic ductal adenocarcinoma (PDAC) as a safe and therapeutically efficient technique through modulating the dense fibrotic stroma in the tumor microenvironment to enhance drug penetration. Considerable NO nanogenerators and NO releasing molecules have been developed to shield the systemic toxicity caused by free diffusion of NO gas. However, on-demand controlled release of NO and chemotherapy drugs at tumor sites remains a problem limited by the complex and dynamic tumor microenvironment. Herein, we present an ultrasound-responsive nanoprodrug of CPT-t-R-PEG2000@BaTiO3(CRB) which encapsulates piezoelectric nanomaterials barium titanate nanoparticle (BaTiO3) with amphiphilic prodrug molecules that consisted of thioketal bond (t) linked chemotherapy drug camptothecin (CPT) and NO-donor l-arginine (R). Based on ultrasound-triggered piezocatalysis, BaTiO3can continuously generate ROS in the hypoxic tumor environment, which induces a cascade of reaction processes to break the thioketal bond to release CPT and oxidize R to release NO, simultaneously delivering CPT and NO to the tumor site. It is revealed that CRB shows a uniform size distribution, prolonged blood circulation time, and excellent tumor targeting ability. Moreover, controlled release of CPT and NO were observed both in vitroand in vivounder the stimulation of ultrasound, which is beneficial to the depletion of dense stroma and subsequently enhanced delivery and efficacy of CPT. Taken together, CRB significantly increased the antitumor efficacy against highly malignant Panc02 tumors in mice through inhibiting chemoresistance, representing a feasible approach for targeted therapies against Panc02 and other PDAC.

The penetration of a peritoneal dialysis catheter into the intestinal cavity is a clinically rare complication. In the present retrospective clinical case series, 11 patients with uraemia who received continuous ambulatory peritoneal dialysis and attended hospital between 2019 and 2023 are described. The median patient age was 61.91 ± 11.33 years. All patients had previously experienced peritoneal dialysis-related peritonitis and were clinically cured by infusing sensitive antibiotics into the abdominal cavity. Colonoscopy was utilised to locate the penetrating catheter and close the perforation with a titanium clip once the catheter had been removed via an external approach. Following a 2–4-week fast, the perforations healed in all 11 patients. The present authors’ experience illustrates that directly removing the catheter and clamping the perforation opening under the guidance of colonoscopy is simple to operate with few complications compared with traditional open surgery.

The ability of robots to write Chinese strokes, which is recognized as a sophisticated task, involves complicated kinematic control algorithms. The conventional approaches for robotic writing of Chinese strokes often suffer from limited font generation methods, which limits the ability of robots to perform high-quality writing. This article instead proposes a developmental evolutionary learning framework that enables a robot to learn to write fundamental Chinese strokes. The framework first considers the learning process of robotic writing as an evolutionary easy-to-difficult procedure. Then, a developmental learning mechanism called “Lift-constraint, act and saturate” that stems from developmental robotics is used to determine how the robot learns tasks ranging from simple to difficult by building on the learning results from the easy tasks. The developmental constraints, which include altitude adjustments, number of mutation points, and stroke trajectory points, determine the learning complexity of robot writing. The developmental algorithm divides the evolutionary procedure into three developmental learning stages. In each stage, the stroke trajectory points gradually increase, while the number of mutation points and adjustment altitudes gradually decrease, allowing the learning difficulties involved in these three stages to be categorized as easy, medium, and difficult. Our robot starts with an easy learning task and then gradually progresses to the medium and difficult tasks. Under various developmental constraint setups in each stage, the robot applies an evolutionary algorithm to handle the basic shapes of the Chinese strokes and eventually acquires the ability to write with good quality. The experimental results demonstrate that the proposed framework allows a calligraphic robot to gradually learn to write five fundamental Chinese strokes and also reveals a developmental pattern similar to that of humans. Compared to an evolutionary algorithm without the developmental mechanism, the proposed framework achieves good writing quality more rapidly.

Immune checkpoint blockade (ICB) therapy still suffers from insufficient immune response and adverse effect of ICB antibodies. Chemodynamic therapy (CDT) has been demonstrated to be an effective way to synergize with ICB therapy. However, a low generation rate of reactive oxygen species and poor tumor penetration of CDT platforms still decline the immune effects. Herein, a charge-reversal nanohybrid Met@BF containing both Fe3O4and BaTiO3nanoparticles in the core and Metformin (Met) on the surface was fabricated for tumor microenvironment (TME)- and ultrasound (US)-activated piezocatalysis-chemodynamic immunotherapy of cancer. Interestingly, Met@BF had a negative charge in blood circulation, which was rapidly changed into positive when exposed to acidic TME attributed to quaternization of tertiary amine in Met, facilitating deep tumor penetration. Subsequently, with US irradiation, Met@BF produced H2O2based on piezocatalysis of BaTiO3, which greatly enhanced the Fenton reaction of Fe3O4, thus boosting robust antitumor immune response. Furthermore, PD-L1 expression was inhibited by the local released Met to further augment the antitumor immune effect, achieving effective inhibitions for both primary and metastatic tumors. Such a combination of piezocatalysis-enhanced chemodynamic therapy and Met-mediated deep tumor penetration and downregulation of PD-L1 provides a promising strategy to augment cancer immunotherapy.

Rotator cuff tear (RCT) is a prevalent shoulder injury that poses challenges for achieving continuous and functional regeneration of the tendon-to-bone interface (TBI). In this study, we controlled the delivery of growth factors (GFs) from liposomal nanohybrid cerasomes by ultrasound and implanted three-dimensional printed polycaprolactone (PCL) scaffolds modified with polydopamine loaded with bone marrow mesenchymal stem cells (BMSCs) to repair tears of the infraspinatus tendon in a lapine model. Direct suturing (control, CTL) was used as a control. The PCL/BMSC/cerasome (PBC) devices are sutured with the enthesis of the infraspinatus tendon. The cerasomes and PCL scaffolds are highly stable with excellent biocompatibility. The roles of GFs BMP2, TGFβ1, and FGF2 in tissue-specific differentiation are validated. Compared with the CTL group, the PBC group had significantly greater proteoglycan deposition (P= 0.0218), collagen volume fraction (P= 0.0078), and proportions of collagen I (P= 0.0085) and collagen III (P= 0.0048). Biotin-labeled in situ hybridization revealed a high rate of survival for transplanted BMSCs. Collagen type co-staining at the TBI is consistent with multiple collagen regeneration. Our studies demonstrate the validity of biomimetic scaffolds of TBI with BMSC-seeded PCL scaffolds and GF-loaded cerasomes to enhance the treatment outcomes for RCTs.

Conventional NO gas generation based on l-arginine (l-Arg) is usually dependent on H2O2and O2, both of which are very limited within the tumor microenvironment, thus greatly limiting l-Arg’s therapeutic effect. Herein, a novel nanoplatform for efficiently triggering NO production based on ultrasound-induced piezocatalysis was developed, which was fabricated by coating amphiphilic poly-l-arginine (DSPE-PEG2000-Arg, DPA) on the piezoelectric material of barium titanate (BTO). The resulting BTO@DPA nanoparticles can efficiently generate H2O2, 1O2, and O2via ultrasound-induced piezocatalysis based on BTO and oxidize the surface arginine to produce NO, which can even further interact with the reactive oxygen species (ROS) to produce more reactive peroxynitrite, thus inducing serious tumor cell apoptosis both in hypoxia and normoxia. After intravenous injection, BTO@DPA accumulated well at the tumor tissue at 4 h postinjection; later, ultrasound irradiation on the tumor not only achieved the best tumor inhibition rate of ∼70% but also completely inhibited tumor metastasis to the lungs via the alleviation of tumor hypoxia. Such a strategy was not dependent on the tumor microenvironment and can be well controlled by ultrasound irradiation, providing a simple and efficient therapy paradigm for hypoxic tumor.

In this study, cubic Cu2O (c-Cu2O) and octahedral Cu2O (o-Cu2O) were prepared through a simple method and applied to activate peroxymonosulfate (PMS) for the degradation of Orange Ⅰ (OⅠ). o-Cu2O exhibited excellent activity for PMS activation with 85.68 % of OⅠ being removed within 30 min, and its catalytic activity remained high even if it was used repeated six times. The effects of PMS concentration, initial pH, anions (Cl–, HCO3–and NO3–) and natural organic matter (NOM) on OⅠ degradation in the o-Cu2O/PMS system were investigated. The mechanism study implied that OⅠ was oxidized via radical (SO4•–, •OH and O2•–) and non-radical (1O2and electron transfer) pathways in the o-Cu2O/PMS system. This work provides an interesting insight into PMS activation by Cu-based catalysts for wastewater treatment.

Si has been considered as one of the most potential new-generation anode materials for high-capacity lithium-ion batteries. However, the lithiation and delithiation of lithium ions during the charge-discharge processes of the Si electrode would give rise to almost four-fold volume expansion, causing structural changes and cracks of the conductive network, limiting the application of Si-based anode material. In this paper, the lithium ions inserting into Si material at various positions and at different doping concentrations of lithium ions was studied by first-principles method. The stability of different insertion sites, the structural changes, band structures and density of States after Li insertion were analyzed. It has been found that the lithium ions doping is an interstitial doping rather than a substitutional one and the tetrahedral center (Td) site is the most stable insertion position. From the band structure analysis, it can be seen that the Si material with the insertion of lithium ions becomes metal-like, and as the concentration changes, silicon changes from an indirect gap semiconductor to a direct gap semiconductor. When the concentration reaches 12.5%, the structural expansion rate increases obviously. This work provides a strategy for the improvement of the Si based anode material used in high-capacity lithium-ion batteries.