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BACKGROUND The corona virus disease 2019 (COVID-19) has been a pandemic for more than one year and estimated to affect the whole world in the near future. CASE SUMMARY Here we reported that one COVID-19 patient with vesicles was treated by bullectomy. The patient’s perioperative laboratory tests were analyzed. The pathological findings of bullectomy were described and compared with those of common bulla cases. CONCLUSION This patient with vesicles underwent bullectomy and had a poor prognosis. He showed diffuse alveolar damage and extensive necrosis in bullectomy specimen. We hope our report will be of interest for clinicians who will treat COVID-19 patients in the future.

In this paper, the mechanical gripper driven by pneumatic artificial muscle is taken as the research object, through theoretical analysis and experimental verification, the feasibility of force feedback control and incremental PID control applied to the mechanical gripper driven by pneumatic muscle is deeply studied, and the results of nondestructive and flexible grasping are obtained. The adaptive control process and deviation comparison link are designed to determine the expected output force of different items. Subsequently, the incremental PID control algorithm is used to eliminate the steady-state error, so as to achieve the self-adaptability of the control system to determine the expected force according to different items.

Background: Protein Kinase C-α (PKC-α) and epidermal growth factor receptor (EGFR) are both involved in diabetic kidney disease; however, the connection between these two proteins during high glucose-induced podocyte injury remains uncertain. Methods: Diabetes was induced in SD rats by streptozotocin (STZ). Fourteen days later, the kidney cortex was removed and subjected to plasma membrane isolation and lipid raft fractionation. In vitro study human podocyte cell line was differentiated and subjected to various treatments. The levels of membranous protein and endocytosis were assessed by biotinylation and sodium 2-mercaptoethane sulfonate (MesNa) treatment. Gö6976 and PYR-41 were used as inhibitors of PKC-α and ubiquitin activating E1 enzyme, respectively. Results: In diabetic rats, the abundance of PKC-α in the membranous fraction and the lipid raft domain is elevated, whereas the EGFR level is reduced. Consistently, in vitro high glucose treated podocytes, membranous EGFR is downregulated with increased PKC-α. Furthermore, the ubiquitination and endocytosis of EGFR are enhanced accompanied by extracellular signal–regulated kinase (ERK) signaling activation and podocyte damage during hyperglycemia. However, these processes can be ameliorated by inhibition of either PKC-α or ubiquitin activating E1 enzyme. Conclusion: During hyperglycemia, PKC-α mediates podocytic EGFR ubiquitination, endocytosis from cell surface and the subsequent ERK activation, which contributes to podocyte injury.

In this paper, the static characteristics of pneumatic muscles are studied by means of theoretical modelling, numerical simulation and experimental verification. Firstly, on the basis of ideal mathematical model, the static mathematical model of pneumatic muscle considering elasticity and friction of rubber is given. Based on the established mathematical model, a pneumatic muscle simulation model is established by using SIMULINK toolbox in MATLAB software environment, which includes model parameter assignment module, pneumatic muscle ideal module, elastic force simulation module, friction simulation module and so on. The influence of elastic force and frictional force of rubber layer on the output force of pneumatic muscle during pneumatic filling is studied by numerical simulation. Finally, a mechanical gripper test rig driven by pneumatic muscle is built. The experimental results show that pneumatic muscle actuator has certain flexible grasping characteristics. The research results provide a reference for the wide application of pneumatic muscle.

Few study was about the fine particulate matter (PM2.5) in Nanning. This paper analyzed the time-space distribution character and influences of PM2.5in Nanning. We collected data of 4 monitoring stations in 2013 year in Nanning, Guangxi. Our results showed that concentration of PM2.5in Nanning were Dec. > Jan > Oct. > Nov. > Mar. > Apr. = Sep. > Feb. > May = Aug. > June > July. The obvious hazy day occurred in winter and autumn. The monitoring stations located in the north suffered higher PM2.5pollution compared with the other stations. Concentration of PM2.5was significantly higher in the month when currents came from island than the month when currents from sea. The increased monthly concentration of PM2.5was associated with the northwest and northeast currents from inland. A combination of lower speed of wind, northwestly wind and regional transport made contribution to the evaluated PM2.5concentration.

Mingzhou bridge in Ningbo is a half-through steel box arch bridge with 450m main-span. The bridge adopts welded steel structures except that abutments are made of steel composite structure. High requirements for the bridge construction technology are put forward because of the restrictions including poor geological conditions for bridge site, height limit for aircraft, narrow channel, frequent typhoon. The mid-span arch rib adopts cable hoisting and stayed buckle cable technology for the construction. This paper introduces the construction method during the assembled process of the mid-span arch rib. The numerical simulation analysis for the construction process is carried out. Stress and deformation of the main arch are in a reasonable range, which indicates completing the bridge construction control target successfully.

Reproductive division in termites is the most significant biological process that leads to the formation of caste-specific differences in tasks and status. However, little is known about the mechanism of reproductive division that underlies caste differentiation. In the present study, ovarian development and stage-specific apoptotic patterns are investigated during oogenesis in reproductive, worker and soldier termites Reticulitermes aculabialis Tsai & Hwang. The results show that the mean lengths of the ovaries of reproductives are two-fold longer compared with those of workers and six-fold longer compared with soldiers. By contrast to the reproductives, the process of oogenesis in the workers includes only the oogonium differentiation stage (stage I) and oocyte growth stage (stage II), and oogenesis in the soldiers stops at stage I. Vitelogenic oocytes (stage III) are absent from workers and soldiers. During stage II in the reproductives and workers, the layer of follicle cells has a thickness of 7.56 ± 0.52 and 2.81 ± 0.34 µm, respectively. In addition, there are significant differences in the number and size of the germ cells at the same stage in the various castes. The existence of two apoptotic patterns during oogenesis is demonstrated by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) assay. First, the majority of the cells showing apoptosis occur at stage I of oogenesis in reproductives, workers and soldiers. Second, DNA fragmentation is demonstrated by TUNEL staining of the follicle cell layers and oocytes at stage II in reproductives. Finally, the proliferation activity of follicle cells in the reproductives is observed by 5-bromo-2′-deoxy-uridine labelling. The level of oogenesis may explain the significant discrepancies in the reproductive capacity among the reproductives, soldiers and workers. These large discrepancies are controlled by apoptosis during early oogenesis.