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The core-tube method is a common method to measure the coal seam gas content (CSGC). However, cutting heat and friction heat will be generated in the core-tube coring process, which will increase the coal core temperature and the coal core gas loss, thus resulting in a large error in the determination of the gas content. The accuracy of the gas content determination is closely related to the temperature variation of coal core during core-taking. Based on this, the team developed the "thermal effect simulation device of coal core in the core-taking process" and carried out the temperature change test experiment of the coal core in the core-taking process under different conditions. The results show that the temperature variation of the coal core during the core-taking process shows four stages: constant temperature, rapid temperature rise, slow temperature rise, and temperature drop. The temperature rise rate, temperature rise duration, and temperature rise peak of the coal core increase with the increase in rotate speed, coal strength, friction area, and frictional load. In the axial direction, the closer to the upper end of the core pipe, the higher the core temperature. In the radial direction, the closer the core is to the wall of the core pipe, the higher the core temperature is. Under the influence of cutting heat and friction heat in the process of core-taking, the maximum heating rate of the core-taking tube wall within 8 min is 20 °C/min, the peak temperature is 158.4 °C, the average temperature of the wall is above 100 °C, and the average temperature rise of the coal core reaches 55.7 °C. Within 60 min, the average temperature of the coal core remained above 50 °C. The order of influence of coal core temperature from large to small is as follows: rotate speed, frictional load, friction area, and coal strength. It can provide a reference for accurately determining CSGC using the core-tube method or designing a coring device to eliminate or reduce the thermal effect during coring.

DNA viruses, such as hepatitis B virus (HBV), human papillomavirus (HPV), human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), and herpes simplex virus (HSV), can cause a wide range of diseases and are considered a global threat to human health. Interferon-inducible protein 16 (IFI16) binds virus DNA and triggers antiviral innate immune responses to restrict viral infection.

The accurate determination of coalbed methane (CBM) content is of great significance for its development and utilization as well as for the prevention and control of coal mine gas disaster. In the process of determining CBM content, the coal–gas adsorption system existing in the natural environment is affected by variable temperature–pressure interactions. In this study, methane (CH4) adsorption tests were carried out on coals at different initial equilibrium pressures (IEPs) and in different cooling processes (CPs). The test results indicate that dominant and retrograde adsorption processes existed in the cooling and adsorption processes of the coal sample reaction chamber. During the adsorption process, the temperature variation broke the original adsorption equilibrium, which in turn induced the pressure change in the coal sample reaction chamber, thus resulting in the retrograde adsorption. The intensity of the dominant adsorption increased and then decreased, causing an increase and then a decrease in the retrograde adsorption rate. The commonly used adsorption kinetic models were modified, including the modified pseudo-first-order kinetic model, modified pseudo-second-order kinetic model, modified Bangham kinetic model (MBKM), modified intra-particle diffusion model and modified double exponential model (MDEM). These modified models were used to describe the kinetic characteristics of the dominant process of CH4 adsorption on coals in a variable temperature and pressure environment. The results show that among the modified kinetic models, the MDEM can describe better the kinetic process of the dominant adsorption, followed by the MBKM. The IEP showed positive correlation with the dominant adsorption rate at the initial stage of cooling. For the two CPs (i.e., 293.15–283.15 K and 273.15–263.15 K), the initial adsorption rates at the IEP of 3.83 MPa were, respectively, about 4 and 3 times higher than those at the IEP of 0.72 MPa. The retrograde adsorption process can be described better by a linear model. A peak retrograde adsorption rate existed throughout the adsorption process and increased with increasing IEP. The study of the kinetic process of CH4 adsorption on the coal matrix under the effect of low temperatures and variable pressures will improve understanding of the CH4 adsorption mechanism in a low temperature and variable pressure environment, and provide theoretical support for the development and application of new techniques for CBM content determination.

Based on the hologram inpainting via a two-stage Generative Adversarial Network (GAN), we present a precise phase aberration compensation method in digital holographic microscopy (DHM). In the proposed methodology, the interference fringes of the sample area in the hologram are firstly removed by the background segmentation via edge detection and morphological image processing. The vacancy area is then inpainted with the fringes generated by a deep learning algorithm. The image inpainting finally results in a sample-free reference hologram containing the total aberration of the system. The phase aberrations could be deleted by subtracting the unwrapped phase of the sample-free hologram from our inpainting network results, in no need of any complex spectrum centering procedure, prior knowledge of the system, or manual intervention. With a full and proper training of the two-stage GAN, our approach can robustly realize a distinct phase mapping, which overcomes the drawbacks of multiple iterations, noise interference or limited field of view in the recent methods using self-extension, Zernike polynomials fitting (ZPF) or geometrical transformations. The validity of the proposed procedure is confirmed by measuring the surface of preprocessed silicon wafer with a Michelson interferometer digital holographic inspection platform. The results of our experiment indicate the viability and accuracy of the presented method. Additionally, this work can pave the way for the evaluation of new applications of GAN in DHM.

The dynamic response of micro-diaphragms vibrating in contact with the surrounding air is of great interest in numerical applications in transducing, sensing and physical measurements. Therefore, effects of air damping and residual stress on the resonant frequencies of circular micromechanical resonators were theoretically analysed in this paper. Thin circular SiC (100) micro-diaphragms of different dimensions subjected to tensile residual stress were fabricated to validate the theoretical model experimentally. In order to study the added mass effect of air, dynamic properties of the micro-diaphragms vibrating in different air pressure were measured. It was found that the virtually added mass effect played a major role in damping the vibration of a diaphragm in air and the magnitude of air damping accordingly exhibited dependence on the environmental pressure ratio. An increase in this ratio led to a stronger effect of air damping on the diaphragm. Residual stress also had a significant effect on the non-dimensional added virtual mass incremental (NAVMI) factor. The NAVMI factor was found to have a continuous plate-membrane transition behaviour when the residual stress of a diaphragm falls in a certain range.

We present a theoretical investigation on the dynamic characteristics of a nanomechanical resonator attached with an adsorbate at an arbitrary position. Cantilevered and bridged configurations are both considered for the resonators. Closed-form expressions relating the exact mode shape and the resonant frequency of the loaded resonator are obtained analytically using the Rayleigh–Ritz theorem, from which the relationship between the adsorbate mass and changes in the dynamic characteristics can be obtained. The results indicate that the mode shape change due to adsorption of a relatively large particle can influence the performance of the nanomechanical resonator considerably.

Mediator of IRF3 activation (MITA, also named as STING/ERIS/MPYS/TMEM173), is essential to DNA virus- or cytosolic DNA-triggered innate immune responses. In this study, we demonstrated the negative regulatory role of RING-finger protein (RNF) 90 in innate immune responses targeting MITA. RNF90 promoted K48-linked ubiquitination of MITA and its proteasome-dependent degradation. Overexpression of RNF90 inhibited HSV-1- or cytosolic DNA-induced immune responses whereas RNF90 knockdown had the opposite effects. Moreover, RNF90-deficient bone marrow-derived dendritic cells (BMDCs), bone marrow-derived macrophages (BMMs) and mouse embryonic fibroblasts (MEFs) exhibited increased DNA virus- or cytosolic DNA-triggered signaling and RNF90 deficiency protected mice from DNA virus infection. Taken together, our findings suggested a novel function of RNF90 in innate immunity., Author summary After the invasion of viruses, the genetic materials, RNA and DNA generated by the viruses, could be recognized by the cytosolic RNA or DNA sensors and then these sensors will initiate the innate immune signaling pathway and protect the host from viral invasion. However, excessive immune responses may cause tissue damage and do harm to the host. Therefore, the innate immune responses should be tightly controlled and turned off timely. MITA is a key adaptor in DNA-sensor signaling pathway. Here, we find that RNF90, a known E3 ubiquitin-protein ligase, interacted with MITA, enhanced the ubiquitination of MITA and promoted the degradation of MITA. RNF90-defient mice showed increased innate immune responses upon DNA virus HSV-1 infection. Our research revealed a new negative regulatory mechanism of the host to manipulate the antiviral innate immune responses.

The fusion of visual and inertial odometry has matured greatly due to the complementarity of the two sensors. However, the use of high-quality sensors and powerful processors in some applications is difficult due to size and cost limitations, and there are also many challenges in terms of robustness of the algorithm and computational efficiency. In this work, we present VIO-Stereo, a stereo visual-inertial odometry (VIO), which jointly combines the measurements of the stereo cameras and an inexpensive inertial measurement unit (IMU). We use nonlinear optimization to integrate visual measurements with IMU readings in VIO tightly. To decrease the cost of computation, we use the FAST feature detector to improve its efficiency and track features by the KLT sparse optical flow algorithm. We also incorporate accelerometer bias into the measurement model and optimize it together with other variables. Additionally, we perform circular matching between the previous and current stereo image pairs in order to remove outliers in the stereo matching and feature tracking steps, thus reducing the mismatch of feature points and improving the robustness and accuracy of the system. Finally, this work contributes to the experimental comparison of monocular visual-inertial odometry and stereo visual-inertial odometry by evaluating our method using the public EuRoC dataset. Experimental results demonstrate that our method exhibits competitive performance with the most advanced techniques.

This paper studies the vibrational behaviors of a distributive mass-loaded microscale circular diaphragm submerged in a fluid. The vibration of the diaphragm involving loadings simultaneously induced by an acoustic field and the adhesion of distributive mass has been investigated. Two different types of adsorbates, namely, in the form of discrete particles (mass only) and a uniform layer (mass and rigidity), are considered and compared. Moreover, the pre-existing stress in the diaphragm has also been taken into consideration. Based on Lamb's hypotheses of the fluid-loaded structure in conjunction with the Rayleigh–Ritz theorem, an analytical solution for the dynamic characteristics of the coupling system, including the resonant frequency, mode shape, and the quality factor, is developed. The results have been compared with those of the finite element simulations, and a good agreement has been obtained. The results reveal that the adsorbate properties contribute differently to the dynamic response of the micro-diaphragm in the fluid, and the contribution may be intervened by tuning the pre-stress. The theoretical model and novel analytical solution are of interest in the design of micro-diaphragm-based biosensing devices.

We present a theoretical analysis of the vibration of a suspended circular diaphragm resonator with a particle at an arbitrary location when considering the effects of plate stiffness and membrane tension in the diaphragm. The analytical expression relating position and mass of a particle attached on a stretched diaphragm with varying residual stress to the resulting shifts in diaphragm resonant frequency is derived. It has been shown that the particle position and mass for the diaphragm configuration can be unambiguously resolved by combining resonant frequencies of the first three consecutive symmetric vibration modes. This finding is verified numerically in finite element modeling using a freestanding circular diaphragm with and without an added particle, and it proves that the method resolves the particle position and mass with high accuracy.

Significant progress was observed in studies of the relationship between oral Helicobacter pylori and gastric cancer and tumors. Based on three distinct and close relationships, namely, the relationship between oral H. pylori and gastric cancer, between oral microbial communities and oral squamous cell carcinoma, and between oral microbial communities of human immunodeficiency virus-infected patients and tumors, this work reviews the relationship between oral microbial communities and tumors. This research also provides reference for further analysis of the relationship between oral microorganisms and tumors to realize early diagnosis of tumor patients through detecting oral microorganisms under adjuvant therapy.

Out-of-plane vibrations of a cantilevered micro-plate attached with a particle are analyzed by using the Rayleigh-Ritz method with deflection functions as the product of mode shapes of beams having the boundary conditions of the plate. An inverse model is then proposed to simultaneously identify the mass and position of the attached particle by the vibration of a micro-plate. The identification procedure has been tested on cantilevered Si micro-plates of different length-to-width ratios deposited with a tiny Pt pad atop. The mass and positions (both in length and width directions) of the Pt pad have been extracted from observed changes in the frequency response of both flexural and torsional vibrations of the micro-plate before and after the Pt deposition. The identified results are in good agreement with estimations based on scanning electron microscopy (SEM) observations. It is thus expected that the use of a micro-plate can significantly enhance mass and position sensing capabilities in comparison to the existing slender microcantilever in applications in biology, medicine and chemistry.

Steam generator has been one of the key equipment in the primary circuit of nuclear power plant. Its safety and economic operation is very vital for nuclear power plant. According to the homogeneous assumption, a vertical U-tube natural circulation two-phase flow steam generator mechanism model was set up with main heat and mass transfer equations depend on modular modeling method in this paper. The simulation results show that, the steady-state parameters errors are small and the dynamic parameters trends are in line with the theoretical analysis, which verifies the rationality of the mechanism model built in this paper.

Tripalmitoyl-S-glycero-Cys-(Lys) 4 (Pam3CSK4) interacted with TLR2 induces inflammatory responses through the mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) signal pathway. Rapamycin can suppress TLR-induced inflammatory responses; however, the detailed molecular mechanism is not fully understood. Here, the mechanism by which rapamycin suppresses TLR2-induced inflammatory responses was investigated. It was found that Pam3CSK4-induced pro-inflammatory cytokines were significantly down-regulated at both the mRNA and protein levels in THP-1 cells pre-treated with various concentrations of rapamycin. Inhibition of phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) signaling did not suppress the expression of pro-inflammatory cytokines, indicating that the immunosuppression mediated by rapamycin in THP1 cells is independent of the PI3K/AKT pathway. RT-PCR showed that Erk and NF-κB signal pathways are related to the production of pro-inflammatory cytokines. Inhibition of Erk or NF-κB signaling significantly down-regulated production of pro-inflammatory cytokines. Additionally, western blot showed that pre-treatment of THP-1 cells with rapamycin down-regulates MAPKs and NF-κB signaling induced by Pam3CSK4 stimulation, suggesting that rapamycin suppresses Pam3CSK4-induced pro-inflammatory cytokines via inhibition of TLR2 signaling. It was concluded that rapamycin suppresses TLR2-induced inflammatory responses by down-regulation of Erk and NF-κB signaling.

Infection rate of hepatitis B virus (HBV) in our country remains high. Many patients showed combined HBV infection; the most common blood system disease is non-Hodgkin’s lymphoma (NHL)-combined HBV infection. Drugs used in treating lymphoma may induce different degrees of HBV reactivation. Such condition may lead to hepatic failure or death. Currently, scholars pay increasing attention to reactivation of HBV by rituximab and/or chemotherapy for NHL-combined HBV patients. This study summarizes research advances in this topic, with a view of providing background information for further research.

By measuring the resonant frequencies of cantilever beams without and with thin films deposited and with the use of the Euler–Bernoulli beam theory, elastic modulus and density of thin films can be determined simultaneously. This simple resonant method was validated using a sputtered Ni film/Si substrate system. The elastic modulus of the Ni film obtained from this method was in excellent agreement with that measured by use of nanoindentation.

This paper presents a theoretical model, based on the Rayleigh-Ritz method, to analyze the dynamic response of circular micro-diaphragms in contact with a fluid. The fluid is assumed to be incompressible, inviscid, and irrotational. In the model, a linear combination of polynomials is utilized to construct the mode shapes, and the Rayleigh quotient for fluid-structure coupling system is implemented to obtain the dynamic characteristics of pre-stressed diaphragms. Theoretical calculations are well validated by a finite element model. The relationships of the natural frequencies and quality factors to the mode shape are systematically investigated. The investigation proves that it is necessary to adopt exact mode shapes, instead of approximate mode shapes, to ensure the accuracy in the theoretical evaluation of the vibration of the diaphragm in the fluid. Furthermore, the quality factor associated with acoustic radiation losses is mode dependent, and its dependency on the mode number shows plate, membrane, and plate-membrane transition behaviors as pre-stress varies. These findings can be useful in the applications of diaphragm-based resonators.This paper presents a theoretical model, based on the Rayleigh-Ritz method, to analyze the dynamic response of circular micro-diaphragms in contact with a fluid. The fluid is assumed to be incompressible, inviscid, and irrotational. In the model, a linear combination of polynomials is utilized to construct the mode shapes, and the Rayleigh quotient for fluid-structure coupling system is implemented to obtain the dynamic characteristics of pre-stressed diaphragms. Theoretical calculations are well validated by a finite element model. The relationships of the natural frequencies and quality factors to the mode shape are systematically investigated. The investigation proves that it is necessary to adopt exact mode shapes, instead of approximate mode shapes, to ensure the accuracy in the theoretical evaluation of the vibration of the diaphragm in the fluid. Furthermore, the quality factor associated with acoustic radiation losses is mode dependent, and its dependency on the mode number shows plate, membrane, ...

The free vibration of circular diaphragms subjected to in-plane tensile biaxial stress while in contact with a fluid is analyzed using the Rayleigh-Ritz method, in which the linear superposition of a number of polynomial functions is used to describe the displacement of the diaphragm. The diaphragm is placed into a hole in an infinite rigid wall, and the fluid is assumed to be incompressible and inviscid. Analytical expressions for the nondimensional added virtual mass incremental factor and the quality factor are easily derived using the proposed method. Our numerical results are validated by comparisons with published theoretical results and a finite element model. This work demonstrates the thermal stress contribution to the nondimensional added virtual mass incremental factor and the quality factor, which is important in the design of circular-diaphragm-based sensors.

Internalization is one of the key steps for anticancer immunoconjugates to deliver the drugs inside of cancer cells. Herein, the internalization property of antiepidermal growth factor receptor (EGFR) monoclonal antibody (mAb) LA22 was evaluated.The binding and internalization properties of LA22 on A549 cells were investigated by using 125I-LA22. In vitro internalization was also confirmed by indirect fluorescent staining. In vivo tumor targeting and internalization of 125I-LA22 were evaluated in the A549 nude mice model.The mAb LA22 showed a high affinity to EGFRs expressed on A549 cells (Kd = 0.69 +/- 0.13 nM). The in vitro internalization of LA22 was time- and temperature dependent. The cell-surface-bound LA22 was rapidly internalized at 37 degrees C. The experimental results of LA22 internalization obtained from radioassay and fluorescent staining were consistent with a good linear correlation. At 72 hours postinjection, a clear gamma-image of tumor was obtain in A549 tumor xenografts, and the tumor uptake of 125I-LA22 was 8.00 +/- 0.61 percent injected dose per gram (%ID/g) (2.19 +/- 0.37 %ID/g for 125I-mIgG). Similar to the in vitro observation, 64.06% of the cell-bound mAb LA22 was internalized into the tumor cells in vivo.The mAb, LA22, is a rapid, high-internalizing antibody, and this property makes it a promising vehicle for tumor-targeted drug delivery.

Tripalmitoyl-S-glycero-Cys-(Lys) 4 (Pam3CSK4) interacted with TLR2 induces inflammatory responses through the mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) signal pathway. Rapamycin can suppress TLR-induced inflammatory responses; however, the detailed molecular mechanism is not fully understood. Here, the mechanism by which rapamycin suppresses TLR2-induced inflammatory responses was investigated. It was found that Pam3CSK4-induced pro-inflammatory cytokines were significantly down-regulated at both the mRNA and protein levels in THP-1 cells pre-treated with various concentrations of rapamycin. Inhibition of phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) signaling did not suppress the expression of pro-inflammatory cytokines, indicating that the immunosuppression mediated by rapamycin in THP1 cells is independent of the PI3K/AKT pathway. RT-PCR showed that Erk and NF-κB signal pathways are related to the production of pro-inflammatory cytokines. Inhibition of Erk or NF-κB signaling significantly down-regulated production of pro-inflammatory cytokines. Additionally, western blot showed that pre-treatment of THP-1 cells with rapamycin down-regulates MAPKs and NF-κB signaling induced by Pam3CSK4 stimulation, suggesting that rapamycin suppresses Pam3CSK4-induced pro-inflammatory cytokines via inhibition of TLR2 signaling. It was concluded that rapamycin suppresses TLR2-induced inflammatory responses by down-regulation of Erk and NF-κB signaling.

This paper proposes a real-time electroencephalogram (EEG)-based detection method of the potential danger during fatigue driving. To determine driver fatigue in real time, wavelet entropy with a sliding window and pulse coupled neural network (PCNN) were used to process the EEG signals in the visual area (the main information input route). To detect the fatigue danger, the neural mechanism of driver fatigue was analyzed. The functional brain networks were employed to track the fatigue impact on processing capacity of brain. The results show the overall functional connectivity of the subjects is weakened after long time driving tasks. The regularity is summarized as the fatigue convergence phenomenon. Based on the fatigue convergence phenomenon, we combined both the input and global synchronizations of brain together to calculate the residual amount of the information processing capacity of brain to obtain the dangerous points in real time. Finally, the danger detection system of the driver fatigue based on the neural mechanism was validated using accident EEG. The time distributions of the output danger points of the system have a good agreement with those of the real accident points.

Enterovirus 71 (EV71) has led to recent outbreaks of hand, foot and mouth disease (HFMD) in China, resulting in high mortality. In this study, several monoclonal antibodies were generated by immunizing mice with two synthetic peptides, SP55 and SP70, containing amino acids 163-177 and 208-222 of VP1. The specificities of the anti-EV71 peptide monoclonal antibodies were confirmed by Western blot analysis and immunocytochemistry against EV71 virus. Most importantly, we have identified a monoclonal antibody, clone 22A12, which shows strong neutralizing activity against EV71 in an in vitro neutralization assay. Because there is no vaccine available and treatment is very limited, mouse anti-EV71 monoclonal antibody, clone 22A12, could be a promising candidate to be humanized and used for treatment of EV71 infection.

Single-crystal tungsten nanobelts with thicknesses from tens to hundreds of nanometers, widths of several micrometers and lengths of tens of micrometers were synthesized using chemical vapor deposition. Surface energy minimization was believed to have played a crucial role in the growth of the synthesized nanobelts enclosed by the low-energy {110} crystal planes of body-centered-cubic structure. The anisotropic growth of the crystallographically equivalent {110} crystal planes could be attributable to the asymmetric concentration distribution of the tungsten atom vapor around the nanobelts during the growth process. The elastic moduli of the synthesized tungsten nanobelts with thicknesses ranging from 65 to 306 nm were accurately measured using a newly developed thermal vibration method. The measured modulus values of the tungsten nanobelts were thickness-dependent. After eliminating the effect of surface oxidization using a core-shell model, the elastic modulus of tungsten nanobelts became constant, which is close to that of the bulk tungsten value of 410 GPa.

Since 2008, enterovirus 71 (EV71) has been responsible for high-mortality seasonal epidemics of hand, foot and mouth disease in China. Currently many groups in the world are in the process of developing EV71 vaccines to combat this deadly disease. We have developed three EV71-specific monoclonal antibodies, and in this study we report the establishment of a fast and cost-effective sandwich ELISA kit for measurement of virus concentration in EV71 vaccines using a pair of mouse anti-EV71 monoclonal antibodies. The system is specific for EV71 virus, with no cross-reactivity to coxsackievirus A16, H1N1, rabies, and hepatitis A. Using a reference EV71 vaccine standard, the sensitivity of the assay kit was determined to be 0.82 U/ml, with a linear range between 3.75 and 120 U/ml.

We present a generalized theoretical analysis of the vibration of a micro/nano bridge resonator with a particle at an arbitrary location by considering the combined effect of the beam stiffness and string tension in the resonator. By combining resonant frequencies of at most three consecutive symmetric vibration modes, the developed model can unambiguously resolve the particle mass and position. The methodology is verified using published results. The finding is further validated numerically by finite element modeling using a microbridge with and without an added particle, which proves that the method resolves the particle mass and position with high accuracy.

Photocrosslinking of the halogen-free flame retardant linear low density polyethylene /poly(ethylene-co-vinyl acetate) (LLDPE/EVA) blends with the intumescent flame retardant (IFR) of phosphorous-nitrogen compound (NP) in the presence of photoinitiator and multifunctional crosslinker and the characterization of related properties have been investigated successfully. The results from the gel content and heat extension rate (HER) show that the LLDPE/EVA/IFR blends filled with NP are readily photocrosslinked by UV-irradiation of 5 s to obtain a gel content of above 75% and reach the HER value of about 50 %. The data from the LOI, UL-94, water-resistant, and mechanical measurements show that photocrosslinking can considerably enhance the mecnanical, flame retardant, and water-resistant properties of the LLDPE/EVA/NP samples.

Recent developments on photoinitiated crosslinking of polyethylene and its industrial application for manufacturing XLPE-insulated wire and cable have been reported in detail. This advanced technology is also very promising for photocrosslinking of halogen-free flame retardant polyolefins and EPDM rabber and their applications of related crosslinked wire and cable.