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Deployable structures based on origami are widely used in the application of actuators. In this paper, we present a novel family of origami-based deployable structures with constant curvature. Two categories of non-flat-foldable and non-developable degree-4 vertices (NFND degree-4 vertices) are introduced. Pyramid structures are constructed based on the NFND degree-4 vertices. Doubly symmetric and singly symmetric spherical origami tubular cells (SOTCs) are established based on pyramid structures. To construct deployable origami modules using SOTCs, linking units are introduced. The mobility of the SOTCs and origami modules is analyzed using constraint screws. To realize the construction and simulation of deployable structures, kinematic and geometric analyses of the doubly symmetric and singly symmetric SOTCs are performed. Finally, we introduce four cases for deployable structures in spherical actuators based on the combination of multiple origami modules. These case studies demonstrate the potential of these deployable origami structures in the design of spherical actuators. [ABSTRACT FROM AUTHOR]

The flight load test technology is of great importance for load designing, strength flight test and life monitoring of the aircraft. In order to realize the real-time distributed aerodynamic load test on the complex wing surface, the data-driven load estimation method based on refine finite element simulation is proposed. The artificial neural network is established with deep-learning method. The data set of the structural response is constructed by the high-precision finite element method, which is used to train the model. The wing load estimation results based on deep learning method is compared and verified with the finite element calculation results. The results show that the average error of the total load is about 0.2%, and the position error of the pressure center is about 1%. The method using several strain test points can estimate and reconstruct the load distribution of the whole wing in real time.

Background: Ventilator dependency following coronary artery bypass grafting (CABG) is often associated with significant morbidity and mortality. However, few reports have focused on the independent risk factors for ventilator dependency following CABG. This study aimed to evaluate the independent risk factors for ventilator dependency following coronary artery bypass grafting (CABG). Methods: The relevant pre-, intra- and post-operative data of patients without a history of chronic obstructive pulmonary disease undergoing isolated CABG from January 2003 to December 2008 in our center were retrospectively analyzed. Elapsed time between CABG and extubation of more than 48 hours was defined as postoperative ventilator dependency (PVD). Results: The incidence of PVD was 13.8% (81/588). The in-hospital mortality in the PVD group was significantly higher than that in the non-PVD group (8.6% versus 2.4%, p=0.0092). Besides the length of ICU and hospital stay, PVD correlated with negative respiratory outcomes. The independent risk factors for PVD were preoperative congestive heart failure (OR=2.456, 95%CI 1.426-6.879), preoperative hypoalbuminemia (OR=1.353, 95%CI 1.125-3.232), preoperative arterial oxygen partial pressure (PO2) (OR=0.462, 95%CI 0.235-0.783) and postoperative anaemia (OR=1.541, 95%CI 1.231-3.783). Conclusions: Preoperative congestive heart failure, preoperative hypoalbuminemia, low preoperative PO2 and postoperative anaemia were identified as four independent risk factors for ventilator dependency following CABG.

Parkinson's disease (PD) is the most frequent neurodegenerative movement disorder. Mutations in the PINK1 gene are linked to the autosomal recessive early onset familial form of PD. The physiological function of PINK1 and pathological abnormality of PD-associated PINK1 mutants are largely unknown. We here show that inactivation of Drosophila PINK1 (dPINK1) using RNAi results in progressive loss of dopaminergic neurons and in ommatidial degeneration of the compound eye, which is rescued by expression of human PINK1 (hPINK1). Expression of human SOD1 suppresses neurodegeneration induced by dPINK1 inactivation. Moreover, treatment of dPINK1 RNAi flies with the antioxidants SOD and vitamin E significantly inhibits ommatidial degeneration. Thus, dPINK1 plays an essential role in maintaining neuronal survival by preventing neurons from undergoing oxidative stress, thereby suggesting a potential mechanism by which a reduction in PINK1 function leads to PD-associated neurodegeneration. neurodegeneration | oxidative stress | Parkinson's disease | SOD1

Abstract: The abnormal hyperphosphorylation of tau protein is one of the hallmarks of Alzheimer disease and other tauopathies; as yet the exact role of various tau kinases in this pathology is not fully understood. Here, we show that injection of isoproterenol, an activator of cAMP-dependent kinase (PKA), into rat hippocampus bilaterally results in the activation of PKA, calcium/calmodulin-dependent kinase II and cyclin-dependent kinase-5, inhibition of protein phosphatase-2A, hyperphosphorylation of tau at several Alzheimer-like epitopes and a disturbance of spatial memory retention 48 h after the drug injection. These findings suggest the involvement of PKA and PKA-mediated signaling pathway in the Alzheimer-like tau hyperphosphorylation and memory impairment. [Copyright &y& Elsevier]