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This paper analyzes the shortcomings of the existing pure tone audiometers, and proposes a system to realize pure tone audiometry and speech audiometry with a new DSP processor. The pure tone test signal produced by the system has accurate frequency, high signal-to-noise ratio, and small harmonic distortion. The noise generator that comes with DSP adds a band-pass filter to realize the generation of narrow-band noise. At the same time, due to the modular structure of software design, the system has good ease of use and scalability. The test results show that the hearing test system has excellent performance and can be better used in hearing medical diagnosis.

Dynamic strain-based methods are promising for bridge status assessment; however, the influences of vehicle parameters variations on their capabilities for damage identification are usually indeterminate. In this paper, parametric study for highway bridge rapid assessment method is conducted under moving vehicle loads, which is based on the distributed macro-strain envelope line. First, the relationship between the average bending stiffness and macro-strain history is studied according to the theory of the strain influence line. To determine the influence of different vehicle parameters (velocity, weight and axle numbers) on the method, a 1:10 scale model of a bridge-vehicle system is established for the parametric experimental study. A type of long-gauge Fiber Bragg Grating (FBG) sensor is used in the experiment. The empirical mode decomposition method (EMD) is applied to extract the static macro-strain component, and the maximum values of the static macro-strain histories are accumulated as the long-gauge strain envelope line. The experimental results show that the proposed method not only effectively identifies the location of damage but also damage extent and is not affected by the parameters of the vehicle. This method has engineering significance in bearing capacity evaluation and post-bridge structure reinforcement design.

In situ monitoring was conducted throughout the construction period to investigate the abnormal deformation of a bridge under construction subjected to sudden cooling by Typhoon Lekima. An FE model considering the temperature field based on measurement data was also established to reveal the exact causes of the bridge’s abnormal deformation and provide theoretical guidance for rehabilitation measures. The FE model simulation and measurement results showed that (1) the exact cause of the abnormal deformation of the bridge was the inconsistency of the temperature field between the top and bottom plates, and the sudden approach of the typhoon aggravated the inconsistency; (2) the abnormal deformation of the construction bridge caused by the typhoon could be addressed with rehabilitation before forming the bridge; (3) an extreme temperature field should be considered in the design of a beam–arch combination bridge. These results can provide a reference for the design and construction of similar bridges.

Structural health monitoring is an important means of obtaining the state information of bridges, and the extracted quasi-static strain signal can reflect the stress state of bridges directly. However, the strain signals acquired during the operation stage of bridges are dynamic, and the strain gauges used in the health monitoring system are short (no more than 10 cm), which means they are easily affected by small damage at the installation parts of bridges and thereby the monitoring signal abnormalities occur. A type of externally affixed long-gauge fiber strain gauge is used to monitor the health of bridges, and the dynamic and quasi-static signal separation method for long-gauge strain sensors is studied under different vehicle loads; at the same time, the dynamic monitoring performance of the long-gauge sensor is investigated in this paper. The quasi-static strain signal extracted from the dynamic macro-strain signal can be used to directly monitor the stress status of the bridge. The results show that the method proposed in this paper is feasible for extracting the quasi-static macro-strain from a dynamic long-gauge strain signal.

A novel damage identification method for concrete continuous girder bridges based on spatially-distributed long-gauge strain sensing is presented in this paper. First, the variation regularity of the long-gauge strain influence line of continuous girder bridges which changes with the location of vehicles on the bridge is studied. According to this variation regularity, a calculation method for the distribution regularity of the area of long-gauge strain history is investigated. Second, a numerical simulation of damage identification based on the distribution regularity of the area of long-gauge strain history is conducted, and the results indicate that this method is effective for identifying damage and is not affected by the speed, axle number and weight of vehicles. Finally, a real bridge test on a highway is conducted, and the experimental results also show that this method is very effective for identifying damage in continuous girder bridges, and the local element stiffness distribution regularity can be revealed at the same time. This identified information is useful for maintaining of continuous girder bridges on highways.

With dramatical population growth and aging worldwide, cancer incidence and mortality become the major public health concern affecting more than millions of people each year [1].

Currently, there have been plenty of researches conducted for two main problems in structural health monitoring, damage and vehicle parameter identification on bridges. However, only a handful of methods could achieve these two functions synchronously, which would cause the redundancy of sensors also the rise of cost in monitoring system. In this paper, a method to identify damage and vehicle parameters, such as axle load, wheelbase and velocity on a bridge simultaneously was proposed, based on the influence line of long-gauge strain. The influence line of long-gauge strain was derived primarily according to conventional strain influence line theory, at the basis of which the relationships among the local element bending stiffness of bridge, vehicle parameters and long-gauge strain were figured out then. The two order difference of long-gauge strain was chosen as the key index to found this identification method. Finally, to verify the reliability of this method, a set of numerical simulations was conducted, whose results showed that this method exhibited good performance.

Long non-coding RNAs (lncRNAs) have been shown to play a critical role in cancer biology and are frequently aberrantly expressed. Despite their important role in pathology, little is known mechanistically regarding their role in gastric cancer (GC) pathogenesis. To characterize the role of lncRNAs in GC pathogenesis, 8 paired human GC tissue samples and matched adjacent normal tissue were examined. Large scale expression profiling of lncRNA and mRNA was performed utilizing microarray technology and validated by qPCR. Differentially expressed lncRNAs were subjected to bioinformatic analysis to predict target genes, followed by the integration of differentially expressed mRNA data and GO and network analysis to further characterize potential interactions. In our study, 2,621 lncRNAs and 3,121 mRNAs were identified to be differentially expressed (≥2.0-fold change) in GC samples relative to their matched counterparts. lncRNA target prediction revealed the presence of 221 potential lncRNA-mRNA target pairs for the 75 differentially expressed lncRNAs and 60 differentially expressed genes. KEGG pathway analysis showed that these target genes were significantly enriched in 7 different pathways, of which the p53 signaling pathway was the most significant and has been previously implicated in GC pathogenesis. Construction of a lncRNA-mRNA correlation network revealed 10 differentially expressed lncRNAs potentially regulating the p53 signaling pathway. Overall, this is the first study perform global expression profiling of lncRNAs and mRNAs relating to GC. These results may provide important information for further insights into the pathogenesis of GC and provide potential targets for future therapeutics.

Ambient vibration tests and analyses of a long-span rigid-frame bridge were conducted using distributed long-gauge fiber-optic sensors. The concept of a long-gauge fiber-optic sensor and it...

Interleukin-12 (IL-12) serves an important role in immune responses and antitumor activity. The study of the association between autophagy and cancer cells remains controversial. The present study aimed to investigate the effect of IL‑12 on autophagy in the human breast cancer cell lines MDA‑MB‑231 and MCF‑7, and the possible molecular mechanism. Breast cancer cells were treated with different concentrations of recombinant IL‑12. The expression of the autophagy-associated protein microtubule‑associated protein light chain 3 (LC3) was determined using western blot analysis, fluorescein isothiocyanate‑labeled LC3 was detected using fluorescence microscopy and autophagosomes were examined using transmission electron microscopy. Alterations in the phosphatidylinositol 3‑kinase/Rac‑α serine/threonine protein kinase (PI3K/Akt) and 5'‑AMP‑activated protein kinase subunit β‑1 (AMPK) pathways, in addition to pathway‑associated proteins, were detected using western blotting, following treatment with IL‑12 and pretreatment with the PI3K/Akt activator insulin‑like growth factor or the AMPK inhibitor compound C. It was observed that IL‑12 was able to upregulate the expression of the autophagy‑associated protein LC3 in a concentration‑ and time‑dependent manner, and induce the formation of autophagosomes in the two cell lines, and that the above effects involved the inhibition of the PI3K/Akt signaling pathway and the activation of the AMPK signaling pathway.

Objective To investigate the effect of endogenous interferon β (IFN-β) on the polarization of M1 macrophages as well as the proliferation and invasion activities of hepatocellular carcinoma cells (HCCs) mediated by M1 macrophages. Methods U937-M1 macrophages derived from human monocytic tumor cells U937 was established and the cell phenotypes were identified by real-time quantitative PCR, ELISA and flow cytometry. After IFN-β gene was knocked down with siRNA or IFN-β was neutralized with IFN-β monoantibody in U937-M1 macrophages, the change of M1/M2 phenotype was again analyzed by the above methods. The expressions of interferon regulatory factor 1 (IRF1) and IRF5 were detected by real-time quantitative PCR and Western blotting. The proliferation and invasion activities of HCCs, which were cultured with conditioned medium (CM) collected from different macrophage groups, were analyzed by CCK-8 assay and Transwell(TM) experiments, respectively. Results U937-M1 macrophages showed higher expressions of interleukin 12p35 (IL-12p35), interleukin 12p40 (IL-12p40), interleukin 12p70 (IL-12p70), interleukin 23p19 (IL-23p19), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and CD86 than U937-M0 did. But both U937-M0 macrophages and U937-M1 macrophages showed low expression of CD206. However, compared with the U937-M1 macrophages, the IFN-β-blocked U937-M1 macrophages presented decreased expressions of the above M1 macrophages-associated markers, but increased expressions of M2 macrophages-associated markers IL-10 and CD206, as well as lower expressions of IRF1 and IRF5. The inhibited proliferation/invasion activities of HCCs mediated by U937-M1 macrophages were reversed by IFN-β-blocked U937-M1 macrophages. Conclusion Blocking endogenous IFN-β could inhibit the U937-M1 polarization status and U937-M1 macrophages-mediated anti-tumor activity of HCCs. IFN-β might be involved in modulating the expressions of IRF1 and IRF5 as well as maintaining the M1 polarization status and its function.

Objective To investigate the effect of IL-12 on autophagy and the relative possible mechanism in HepG2 and SMMC-7721 human hepatoma cells. Methods The hepatoma cells were treated with IL-12 (10 ng/mL) for 6 hours. Western blotting was applied to detect the expressions of microtubule-associated protein 1 light chain 3 (LC-3), Beclin 1 and the phosphorylated levels of protein kinase B (AKT), mammalian target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3); immunofluorescence assay (IFA) and transmission electron microscopy (TEM) were used to observe the formation of autophagosome. After STAT3 was inhibited by STATTIC or siSTAT3 and AKT was activated by insulin-like growth factor (IGF-1), Western blotting and IFA were performed again to analyze the change of IL-12-induced autophagy. After the cells were treated with IL-12 (10 ng/mL) for 1, 2, 3, 4, 5 days, CCK-8 assay was used to determine the growth ability. After the hepatoma cells were treated with IL-12 (10 ng/mL) for 48 hours, trypan blue staining was used to detect the death rate of the cells. After cell autophagy was inhibit by siBeclin 1, CCK-8 assay and trypan blue staining were performed again to study the effect of IL-12 on the proliferation and death of human hepatoma cells. Results IL-12 induced autophagy and inhibited cell growth in the hepatoma cells. Silencing Beclin 1 gene enhanced IL-12-mediated growth inhibition and cell death. Furthermore, IL-12 treatment also decreased the expressions of p-AKT, p-mTOR and p-STAT3. The pretreatment of siSTAT3 or STATTIC inhibited STAT3-enhanced IL-12-induced autophagy. Accordingly, activation of AKT with IGF-1 decreased IL-12-induced autophagy. Conclusion IL-12 could induce autophagy through AKT/mTOR/STAT3 signaling pathways and the induction of autophagy attenuates the growth-inhibitory effect of IL-12 on hepatoma cells.

Interleukin-12 (IL-12), a member of interleukin family, plays a critical role in immune responses and anti-tumor activity. In this study, the effects of IL-12 on monocytic tumor cell lines differentiation to macrophagocyte and its likely mechanism was investigated. We examined the differentiation markers, morphological and functional changes, and possible mechanism in IL-12-treated THP-1 and U937 cells. It was found that IL-12 could up-regulated macrophage surface marker CD68 and CD11b expression in a time-dependent manner. Morphologically, after IL-12 treatment, THP-1 and U937 cells became round or irregular shape, even stretched many cell membrane protuberances; some cell nuclei became fuzzy or completely disappeared, and the chromatin appeared dense and cordlike. Furthermore, IL-12-induced monocytic tumor cell differentiation was accompanied by the growth arrest with G1-phase accumulation and S-phase reduction; apoptosis increased with anti-apoptosis protein Bcl-2 down-expression and pro-apoptosis protein Fas up-regulation, and enhanced phagocytosis function. The IL-12-induced macrophage differentiation of THP-1 and U937 cells was associated with the up-regulation of c-fms expression and the CSF-1R Tyr 809 site phosphorylation. These findings have revealed that IL-12 could induce monocytic tumor cells directional differentiation into macrophage-like cells, and its mechanism is possible connected with the up-regulation of c-fms expression and the phosphorylation of CSF-1R Tyr-809 site.

Designed a contrast pinhole detect testing including water leak method, electrical method and improved electrical method, and concluded that the water leak method is most suitable as the arbitration method, and recommended the national standard add the requirement on electrolytic liquid filling volume of electrical test in order to improve detection accuracy.

Fiber optic sensing technology has been widely used in civil infrastructure health monitoring due to its various advantages, e.g., anti-electromagnetic interference, corrosion resistance, etc. This paper investigates a new method for stiffness monitoring and damage identification of bridges under moving vehicle loads using spatially-distributed optical fiber sensors. The relationship between the element stiffness of the bridge and the long-gauge strain history is firstly studied, and a formula which is expressed by the long-gauge strain history is derived for the calculation of the bridge stiffness. Meanwhile, the stiffness coefficient from the formula can be used to identify the damage extent of the bridge. In order to verify the proposed method, a model test of a 1:10 scale bridge-vehicle system is conducted and the long-gauge strain history is obtained through fiber Bragg grating sensors. The test results indicate that the proposed method is suitable for stiffness monitoring and damage assessment of bridges under moving vehicular loads.