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The free vibration of rotating bending-torsional composite Timoshenko beams (CTBs) with arbitrary boundary conditions is analyzed. The composite material coupled rigidity, Coriolis effects and the separation of the cross-section’s mass and shear centers are considered and they will cause the bending-torsion coupled vibration of the beam. Based on the Hamilton’s principle, the governing partial differential matrix equation of motion of the beam are formulated with variable coefficients. Those equations containing variable coefficients are expressed in a special matrix form in terms of the flexural translation, rotation of cross section and torsional rotation of the beam. The differential transform matrix method (DTMM), which is an improved approach from the traditional differential transform method (DTM), is proposed to deal with the governing matrix equation with corresponding boundary conditions. The mode shapes and natural frequencies of the beam are obtained. Cantilevers are calculated as examples to verify the present theory and investigate the dynamic characteristics of the rotating CTB. The present results are consistent with those reported in the literature and those calculated from COMSOL. The influence of the composite material rigidity, rotation speed, hub radius and axial load on the natural frequencies and mode shapes of the beam are studied, while the frequency veering and mode shift phenomena are observed. Furthermore, the beam’s critical buckling loads corresponding to the axial load are found.

PURPOSE We investigated the effectiveness, safety and compliance of Zheng's Supine Rehabilitation Exercise (ZSRE) as a rehabilitation programme among elderly patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). PATIENTS AND METHODS About 82 elderly patients with AECOPD were divided into a rehabilitation group and control group on their admission day, and both groups received routine medical treatment. Patients in the rehabilitation group started ZSRE on the second day of admission and continued until 8 weeks after discharge. RESULTS At the 9th week after discharge, the COPD Assessment Test (CAT), 6-minute walking distance (6MWD) and Modified Medical Research Council Dyspnea Scale (mMRC) in the rehabilitation group were all significantly better than those in the control group (P

A novel nonlinear dynamic modeling approach is proposed for the T-shaped beam structures widely used in the field of aerospace. All of the geometrical nonlinearities including the terms in the deformation of the beams, the terms at the connections, and the free ends of beams are considered in the dynamic modeling process. The global mode method is employed to determine the natural frequencies and global mode shapes of the linearized system. The validity and accuracy of the derived model are verified by comparing the natural frequencies obtained with those calculated from FEM. Adopting the Galerkin truncation procedure, a set of reduced-order nonlinear ODEs is obtained for the structure. A study on the variation of dynamic responses taking the different numbers of global modes into account is performed to determine the number of modes taken in nonlinear vibration analysis. A comparison between the responses of the system with linear or nonlinear matching and boundary conditions is given to evaluate the importance of neglecting and reserving the nonlinear terms in matching and boundary conditions. It is shown that ignoring the nonlinear terms in both matching and boundary conditions may significantly alter the responses while developing the discretized governing ODEs of the structure.

High mobility group protein B1 (HMGB1), a highly conversed non-histone nucleoproteins with strong pro-inflammatory property, is one of the inflammatory mediator of the acute respiratory distress syndrome (ARDS). Numerous studies have confirmed that HMGB1 regulates ARDS by binding to receptor for advanced glycation end product (RAGE), Toll-like receptor (TLR) and etc. And it can significantly increase the mortality of ARDS. But the mechanism of HMGB1 release is still unclear. This study focuses on the HMGB1 release progress, which connected with Janus kinases/signal transducer and activator of transcription (JAK/STAT), nuclear factor-κB (NF-κB), Notch, inflammasome, tumor necrosis factor (TNF), mitogen-activated protein kinase (MAPK), reactive oxygen species (ROS), peroxisome proliferator-activated receptor (PPAR) and other signaling or dependent pathways in ARDS.

SARS-CoV-2 vaccination has been launched worldwide to build effective population-level immunity to curb the spread of this virus. The effectiveness and duration of protective immunity is a critical factor for public health. Here, we report the kinetics of the SARS-CoV-2 specific immune response in 204 individuals up to 1-year after recovery from COVID-19. RBD-IgG and full-length spike-IgG concentrations and serum neutralizing capacity decreases during the first 6-months, but is maintained stably up to 1-year after hospital discharge. Even individuals who had generated high IgG levels during early convalescent stages had IgG levels that had decreased to a similar level one year later. Notably, the RBD-IgG level positively correlates with serum neutralizing capacity, suggesting the representative role of RBD-IgG in predicting serum protection. Moreover, viral-specific cellular immune protection, including spike and nucleoprotein specific, persisted between 6 months and 12 months. Altogether, our study supports the persistence of viral-specific protective immunity over 1 year., The quality of immune response to SARS-CoV-2 is thought to wane over time, but it is unclear how long it can persist. Here the authors show persistent immune responses in a large number of patients over the course of a 1-year follow-up from the time of recovery from COVID-19.

Ambient temperatures influence plant growth and development, however very little is known about changes in root growth in response to ambient temperature change. Here, we performed transcriptome profiling and compared the differences in gene expression at lower and higher temperatures compared with normal plant growth temperatures. Our analysis of the biological processes and molecular functions regulated by differentially expressed genes revealed that low temperature upregulated carbohydrate metabolism and transmembrane transport, and downregulated signal transduction and defense. High temperature upregulated metabolic processes, transport, and auxin biosynthesis, and downregulated catabolic processes. We found that increased temperature specifically affected the levels of Arabidopsis response regulators, ARR1 and ARR12, to decrease cytokinin signaling, altered the level of the brassinosteroid receptor BRI1 to downregulate brassinosteroid signaling, and changed the level of the gibberellin receptor DELLA to upregulate gibberellin signaling and mediate root elongation. These data contribute to our knowledge of how root growth adapts to elevated ambient temperature under climate warming.

Purpose To use radionuclide imaging to investigate silent aspiration among patients recovering from an acute exacerbation of chronic obstructive pulmonary disease (AECOPD). We also evaluated the effects of exercise-induced dyspnoea on silent aspiration in COPD patients. Patients and methods Recovering AECOPD patients admitted to the First Affiliated Hospital of Guangzhou Medical University between December 2013 and December 2015 were selected for the radionuclide aspiration test along with healthy volunteers of similar age. Aspiration-negative AECOPD patients were randomized into two subgroups. Patients in group A performed symptom-limited incremental cycle exercise test. Patients in group B were resting on the exercise bicycles. Aspiration-negative healthy volunteers performed symptom-limited incremental cycle exercise test (group C). Three groups performed a radionuclide aspiration test 30 min after exercise. Results The silent aspiration rates among recovering AECOPD patients and healthy volunteers were 44.19% (57/129) and 0 (0/18) (P = 0.00). The aspiration rates in groups A and B were 33.33% (10/30) and 23.33% (7/30), (P = 0.39) and groups A and C were 33.33% (10/30) and 0% (0/12), (P = 0.04). Conclusion Recovering AECOPD patients had significantly higher silent aspiration rates than healthy volunteers of similar age. The evidence is not strong enough to support the patients with exercise-induced dyspnoea-increased aspiration rate.

Nanoscale Cu1−xMnxO powder is prepared by using the combustion synthesis technique with two different fuels. The structural properties of the powder are determined using Rietveld refinement of X-ray diffraction data, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy, while its magnetic properties are analyzed by means of hysteresis loop and temperature dependence of magnetization. The results show that (1) the Cu1−xMnxO nanocrystal is of monoclinic CuO structure, with grain size of 10–30 nm varying with the type of fuel, the nitrate/fuel ratio (N/F), and the Mn concentration, the doping of Mn has a little influence on the lattice parameters; (2) when the Mn concentration is higher than 7%, a small amount of impurity phase of CuMn2O4 appears and annihilates the potential cation vacancies; (3) all of the samples with x≥5% exhibit low-temperature ferromagnetism with the Curie temperature of ∼90 K, which increases slightly by raising the Mn concentration; (4) the paramagnetic moment per Mn ion is around 2–4 bohr magneton above the Curie temperature, which decreases with increasing Mn concentration, implying that the nearest Mn ions are antiferromagnetically coupled and the ferromagnetic order could originate from the super-exchange of next nearest Mn ions along the [1 0 1] direction.

Fe-doped CuO (Cu1−xFexO) nanocrystals (NCs) (x=0, 0.02, 0.05, 0.1, 0.15, 0.2, 0.25, and 0.3) are prepared by using the urea nitrate combustion method. X-ray diffraction (XRD) analysis confirmed the monoclinic structure of CuO. Single-phase structure is obtained for the 0%–20% Fe-doped CuO, whereas for the 25% and 30% Fe-doped CuO material, secondary phase, α-Fe2O3, is presented. Rietveld refinements of XRD data revealed that with an increase in Fe doping level, there is a monotonic increase in cation vacancies in the Fe-doped samples. X-ray photoelectron spectroscopy measurements on the Cu0.98Fe0.02O sample revealed that the Cu2+ sites are partly substituted by Fe3+ ions. The microstructure is investigated by high-resolution transmission electron microscopy. The magnetic hysteresis loops and the temperature dependence of magnetization of the samples indicated that the samples are mictomagnetic of ferromagnetic domains originated from ferromagnetic coupling between the doping Fe ions in Cu1−xFexO NCs rando...