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The article presents a prospective, multicenter survey to evaluate the causes of chronic cough across five regions in China using a modified diagnostic algorithm. It also investigated the effects of geography, seasonality, age and sex which were deemed not associated with the spectrum of chronic cough. It finds that cough variant asthma (CVA), upper airway cough syndrome (UACS), eosinophilic bronchitis (EB) and atopic cough (AC) were the most common causes, accounting for 75.2-87.6% of cases.

Nonlinear dynamic behaviors of drilling shaft system in boring and trepanning association deep hole drilling are investigated. The effects of the mass eccentricity and the cutting force fluctuating can be taken into consideration in the model of drilling shaft system. Nonlinear hydrodynamic forces are adopted to increase the numerical accuracy. Based on the isoparametric finite element with eight nodal points method, the nonlinear hydrodynamic forces and their Jacobian matrices of compatible accuracy are calculated simultaneously. To solve the nonlinear dynamic orbit of drilling shaft system, the period T of the periodic orbit of the nonlinear drilling shaft system is drawn into the governing equation of the system explicitly by changing the time scale. Then, the period T is taken as a parameter in the iterations of the shooting method. The periodic orbit and its period of the drilling shaft system are determined rapidly by generalized shooting method. The local stability and dynamic behaviors of periodic motion with the change of the drilling shaft design parameters value are obtained by the Floquet theory. The numerical results indicate the rich and complex dynamic behaviors of the drilling shaft system, such as periodic, quasiperiodic, jumped solution, and coexistence of multisolution and can make a good reference for the dynamic design of drilling shaft system in deep hole drilling. [ABSTRACT FROM AUTHOR]

Background and objective: Nerve growth factor (NGF)/tyrosine kinase receptor A (TrkA) signalling may play an important role in the pathogenesis of asthma, and SH2-Bβ, a TrkA-binding protein, modulates the NGF signalling pathway. In this study, SH2-Bβ expression in alveolar macrophages (AM) in guinea pig BAL fluid and its role in asthma pathogenesis through the NGF–TrkA signalling pathway were investigated. Methods: Guinea pigs were randomized into five groups: control, a model of asthma, anti-SH2-Bβ antibody treatment, anti-NGF antibody treatment and anti-TrkA antibody treatment. The asthmatic model was established in guinea pigs by inhalation of ovalbumin. Specific anti-SH2-Bβ, anti-NGF and anti-TrkA antibodies were administered and AM were isolated from BAL fluid to assess SH2-Bβ expression using an immunofluorescence assay. SH2-Bβ and TrkA protein expression were determined by western blotting, IL-1β and IL-4 levels in the BAL fluid supernatants were determined by ELISA, and pathological changes in the bronchi and lung tissues were examined by HE staining. Results: Lymphocyte, eosinophil and total inflammatory cell numbers in BAL fluid were significantly higher in the asthma model group than in the other groups ( P < 0.01). NGF expression in the asthma model group was significantly higher than that in the PBS control group ( P < 0.01). SH2-Bβ was expressed in AM of control animals and expression was significantly higher in the asthma model than in the other groups ( P < 0.01). TrkA protein expression was significantly higher in the asthma model group than in the PBS group ( P < 0.01), and treatment with anti-NGF antibody resulted in significant reduction of TrkA expression ( P < 0.01). Conclusions: SH2-Bβ is expressed in AM of normal guinea pigs, and SH2-Bβ may participate in asthma pathogenesis through the NGF–TrkA signalling pathway. [ABSTRACT FROM AUTHOR]

It is significant to perform bonding state detection of explosive clad structure to avoid serious accidents. Due to the complexity of its bonding interface, constructing the detection index which is sensitive to the change of the bonding state has turned into a challenging task. Therefore, a novel method based on the Hilbert envelop energy ratio of mono-model signals is proposed for this task. Benefiting from the advantage of only related with intrinsic property parameters such as damping ratios, natural frequencies and principal modes; the Hilbert envelope energy ratio of arbitrary two order model signals from impulse vibration response can reflect the inherent property of the multi-degree-of-freedom (MDOF) system. In addition, it has been found that the bonding state of explosive clad structure is mainly related with the structural damping ratio. Introduce the general characteristic of MDOF system into explosive clad structure, the detection index based on the Hilbert envelope energy ratio of mono-model signals is constructed for the bonding state detection of explosive clad structure. The proposed method is applied to the bonding state detection of explosive clad pipes to validate its robustness and effectiveness. Compared with the detection method based on optimized dual-tree complex wavelet transform (ODTCWT) and time entropy index proposed by the authors in previous research, the results indicate that the robustness and effectiveness of the proposed method in this paper is more superior to that of the detection method based on ODTCWT and time entropy index. [ABSTRACT FROM AUTHOR]