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Abstract Objective To investigate the correlation between acetylcholine receptor antibodies (AChR‐Ab) concentration levels and individualized clinical symptoms in patients with AChR myasthenia gravis (AChR‐MG) in China. Methods ELISA was used to determine the concentration of AChR‐Ab in patients with MG. The Myasthenia Gravis Foundation of America (MGFA) Clinical Classification, Quantitative Myasthenia Gravis (QMG) score, and MG‐specific activities of daily living (MG‐ADL) scoring systems were used to evaluate the clinical status of patients. Spearman correlation analysis was used to determine the correlation between the AChR‐Ab concentration and clinical score. The changes in the antibody concentration and clinical score are shown in MGFA‐antibody concentration–treatment plots. Results Autoantibody detection tests were performed in 67 patients, and their clinical scores were recorded. Forty‐nine patients received immunosuppressive therapy, 17 patients received pyridostigmine only, and 1 patient under thymectomy without any medication. The AChR‐Ab concentration correlated with the MGFA Classification in 5 (29.4%) patients in the pyridostigmine‐only group and 15 (30.6%) patients in the immunosuppressive drug group. The changes in the MGFA Classification preceded the changes in the AChR‐Ab concentration in 4 (23.5%) patients treated with pyridostigmine and 10 (20.4%) patients on immunosuppressive drugs. In patients on oral non‐steroidal immunosuppressants, the AChR‐Ab concentration changed by more than 50%, whereas the MGFA Classification did not increase. The AChR‐Ab concentration decreased in 17/32 (53.1%) patients after thymectomy, and then increased, whereas the AChR‐Ab concentration increased in 15/32 (46.9%) patients and the MGFA Classification decreased in 27/32 (81.8%) patients after thymectomy. The AChR‐Ab concentration presented a slight correlation with the corresponding MGFA, QMG, and MG‐ADL in patients with thymoma. Discussion In the Chinese AChR‐MG population, the Changes in the AChR‐Ab concentration in individuals with AChR‐MG did not consistently correlate with the severity of clinical symptoms.

At present, large-scale and high-efficiency microalgal cultivation is the key to realizing the technology for carbon capture and storage (CCS) and bioresource recovery. Meanwhile, tubular photobioreactors (PBRs) have great potential for microalgal cultivation due to their high productivity. To improve the mixing performance and flashing-light effect, a novel tube PBR with the inner tube tangential to the outer tube was developed, whose radial aeration pores are situated along the length of the inner tube. The direction of aeration, aeration rate, light/dark cycle period (L/D), light-time ratio, average turbulent kinetic energy (TKE), and degree of synergy between the velocity and direction of the light field in the PBR were optimized by a computational fluid dynamics (CFD) simulation and field synergy theory. The results show that a downwards aeration direction of 30° and an aeration rate of 0.7 vvm are the most conducive to reducing the dead zone and improving the light/dark cycle frequency. Compared to the concentric double-tube PBR, the light/dark cycle frequency and light time of the tangent double-tube PBR increased by 78.2% and 36.2% to 1.8 Hz and 47.8%, respectively, and the TKE was enhanced by 48.1% from 54 to 80 cm2·s−2. Meanwhile, field synergy theory can be extended and applied to the design of tubular microalgae PBRs, and the average synergy of the light and velocity gradients across the cross-section increased by 38% to 0.69. The tangential inner tube aeration structure generated symmetrical vertical vortices between the light and dark areas in the PBR, which significantly improved the mixing performance and flashing-light effect. This novel design can provide a more suitable microenvironment for microalgal cultivation and is promising for bioresource recovery applications and improving the yield of microalgae.

Abstract Background Accumulating researches have shown that epithelial-mesenchymal transition (EMT) contributes to tumor metastasis. Leptin, a key adipokine secreted from adipocytes, shapes the tumor microenvironment, potentiates the migration of breast cancer cells and angiogenesis, and is also involved in EMT. However, the potential mechanism remains unknown. This study aims to explore the effect of leptin on EMT in breast cancer cells and the underlying mechanism. Methods With the assessment of EMT-associated marker expression in MCF-7, SK-BR-3, and MDA-MB-468 cells, the effect of leptin on breast cancer cells was analyzed. Besides, an array of pathway inhibitors as well as RNA interference targeting pyruvate kinase M2 (PKM2) were used to clarify the underlying mechanism of leptin-mediated EMT in vitro and in vivo. Results The results demonstrated that leptin promoted breast cancer cells EMT, visibly activated the PI3K/AKT signaling pathway, and upregulated PKM2 expression. An antibody against the leptin receptor (anti-ObR) and the PI3K/AKT signaling pathway inhibitor LY294002 significantly abolished leptin-induced PKM2 expression and EMT-associated marker expression. SiRNA targeting PKM2 partially abolished leptin-induced migration, invasion, and EMT-associated marker expression. In vivo xenograft experiments indicated that RNA interference against PKM2 suppressed breast cancer growth and metastasis. Conclusions Our data suggest that leptin promotes EMT in breast cancer cells via the upregulation of PKM2 expression as well as activation of PI3K/AKT signaling pathway, and PKM2 might be one of the key points and potential targets for breast cancer therapy.

Fructose-1,6-bisphosphatase 1, a rate-limiting enzyme in gluconeogenesis, was recently shown to be a tumor suppressor. However, the functions of fructose-1,6-bisphosphatase 1 in the regulation of mitophagy and apoptosis remain unknown. Here, we investigated the effects of fructose-1,6-bisphosphatase 1 on mitophagy and apoptosis as well as their underlying mechanisms in breast cancer cells. In this work, the messenger RNA and protein expression of various molecules were determined by quantitative realtime polymerase chain reaction and western blot, respectively. Gene-expression correlations were obtained from The Cancer Genome Atlas Breast Cancer database and analyzed using cBioPortal. The levels of cellular reactive oxygen species and apoptotic index were detected by flow cytometry. The mitochondrial membrane potentials were assessed with a JC-1 fluorescent sensor. Subcellular structures were observed under a transmission electron microscope. The intracellular distribution of translocase of outer membrane 20 was detected by immunofluorescence staining. Protein–protein interactions were analyzed by immunoprecipitation. Our results indicated that fructose-1,6-bisphosphatase 1 expression was negatively correlated with autophagy level in breast cancer. Fructose-1,6-bisphosphatase 1 restrained autophagy activity by increasing the level of p62 and decreasing the levels of LC3 and Beclin 1. Additionally, fructose-1,6-bisphosphatase 1 promoted cell apoptosis by upregulating the levels of intracellular ROS and expression of pro-apoptotic proteins such as cleaved PARP, cleaved Caspase 3, and Bax and downregulating the levels of anti-apoptotic proteins such as PARP, Caspase 3, and Bcl-2. Finally, fructose-1,6-bisphosphatase 1 limited the efficient removal of diseased mitochondria and reduced the messenger RNA and protein expressions of HIF-1α, BNIP3L/NIX, and BNIP3. More importantly, fructose-1,6-bisphosphatase 1 facilitated co-action between Bcl-2 and Beclin 1, which may be important in the mechanism of fructose-1,6-bisphosphatase 1–mediated mitophagy inhibition. In summary, loss of mitophagy by fructose-1,6-bisphosphatase 1–mediated repression promotes apoptosis in breast cancer.

Co-pelletization of waste biomass and microalgae is an attractive option for using bioenergy efficiently. This work investigates the potential of microalgae as a binder to improve the energy consumption and physical and thermal properties of a novel pellet. Wood waste biomass was blended with microalgae in proportions of 15%, 30%, and 50% to investigate its properties using a single pelleting device and thermodynamic analysis. The results showed that, under the conditions of temperature (80−160 °C), pressure (120−200 MPa), and moisture content (6%−14%), blending microalgae can effectively increase the bulk density and mechanical durability of the pellets by 9%−36% and 0.7%−1.6%, respectively, and can significantly reduce the energy consumption of pelleting by 23.5%−40.4%. Blending microalgae can significantly reduce the energy consumption of pelleting by 23.5%−40.4%. Moreover, when the amount of Chlorella vulgaris powder (CVP) is 50%, a maximum bulk density (BD) of 1580.2 kg/m3, a durability (DU) of 98%, and a minimum energy consumption of 25.2 kJ/kg were obtained under the optimum conditions of temperature (120 °C), pressure (120 MPa), and moisture content (10%), respectively. Besides, the interaction between the microalgae and sawdust does exist, and their effect on the co-combustion process is inhibitive (0−300 °C) and accelerative (300−780 °C). When the amount of microalgae was 15%, the average activation energy of the pellet was a minimum value, which was 133.21 kJ/mol and 134.60 kJ/mol calculated by the Kissinger−Akahira−Sunose method and Ozawa−Flynn−Wall method, respectively. Therefore, the energy consumption, physical, and thermal properties of the novel pellet could be improved and meet the ISO standard (International Organization for Standardization of 17225, Geneva, Switzerland, 2016) by blending 15% of microalgae. Overall, the use of microalgae as a binder can indeed improve pellet quality, and it can be considered a significant way to utilize microalgae in the future.

At present, mobile robotic manipulators have been greatly developed. However, these further promotions are limited by a low load capacity and short operation time. The above problems can be improved by using a hydraulic drive mode and increasing the system energy efficiency. In this paper, a novel energy-efficient wobble plate hydraulic joint is presented, which has the characteristics of having a small size, lightweight, large load capacity, and high energy efficiency. Based on the efficiency analysis in traditional robotic manipulators, this paper presents a novel hydraulic joint with a multi-chamber drive structure. Kinematics model and dynamics model are both established for the analysis of the mechanical characteristics, and the functional relationship between the input and output is depicted by numerical simulation. Based on the structural characteristics and control principle, the load matching controller is designed and specific control processes are formulated. Combined with a strategy of load matching, the servo control system is established and the energy-saving effect is verified by simulation. The result shows that the wobble plate hydraulic joint can change connections between a high-pressure circuit and different working chambers, which realizes the match between the output torque and load torque. With the load matching controller, the energy consumption of the wobble plate joint is greatly reduced, which contributes to a considerably improved energy efficiency. The research in this paper not only lays a theoretical foundation for the development of a wobble plate hydraulic joint, but also provides guidance for the improvement of the hydraulic system energy efficiency in mobile robotic manipulators.

The frictional modelling literature is reviewed, and it is demonstrated that unrealistic drift results when the shape coefficient is 1.0 for the LuGre and the integral friction models. Drift will not occur but other dynamic friction characteristics can't be represented when the shape coefficient is 0. Based on the above, the LuGre friction model and the Integral friction model are improved. The velocity-friction characteristic, the stick-slip and the cycling caused by friction and the drift are compared in simulation. The results show that the improved friction model well reflects realistic friction dynamic characteristics and avoids drift. Finally, the improved friction model is used in a nonlinear mathematic model of a valve controlled hydraulic cylinder system. The cylinder's motion at low velocity is simulated and the related experimental results are presented. The results show that the improved friction model gives realistic low velocity motion of the cylinder.

In this paper, we present an innovative bilaterally-controllable self-locking mechanism that can be applied to the micro in-pipe robot. The background and state of the art of the inchworm micro in-pipe robot is briefly described in the very beginning of the paper, where the main factors that influence the traction ability are also discussed. Afterwards, the micro in-pipe robots’ propulsion principle based on a unidirectional self-locking mechanism is discussed. Then, several kinds of self-locking mechanisms are compared, and a new bilaterally-controllable self-locking mechanism is proposed. By implementing the self-locking mechanism, the robot's tractive force is no longer restricted by the friction force, and both two-way motion and position locking for the robot can be achieved. Finally, the traction experiment is conducted using a prototype robot with the new bilaterally-controllable self-locking mechanism. Test results show that this new self-locking mechanism can adapt itself to a diameter of >17~>20 mm and has a blocking force up to 25N, and the maximum tractive force of the in-pipe robot based on such a locking mechanism is 12N under the maximum velocity of 10mm/s.