Search

The high temperature generated on the contact interfaces of the conical friction element in clutches due to the sliding frictional heat should be responsible for the synchronization failure. In this study, an analytic model taking account of the capsizing moment and stress singularity at the end of the contact interface is established to solve the contact pressure distribution. Then, a three-dimensional finite element model has been developed to analyze the transient thermal behavior of the conical friction element. The contact pressure and temperature distribution generated along the contact interfaces are investigated and compared between the proposed new model, the combined wear assumption, and the uniform pressure assumption. Furthermore, the variations in temperature obtained from the new model and the other two assumptions are compared to the experimental results. The results show that the temperature simulated by the new model has a good agreement with reality. The maximum temperatures obtained by the new model are 95.53 °C and 71.67 °C, and the measured values are respectively 84.98 °C and 65.46 °C at the measuring position under the given two working conditions.

Background: This study aims to explore the potential molecular mechanism of Er Miao San (EMS) in rheumatoid arthritis (RA) on the basis of network pharmacology and molecular docking. Methods: The active ingredients and targets of EMS, RA and pathways were obtained through multiple databases. Common targets were analyzed by protein-protein interactions (PPIs) with the STRING database. Gene Ontology (GO) and KEGG enrichment analyses were conducted with the DAVID database to annotate targets of RA and common targets. Hub genes were obtained by the degree algorithm with the cytoHubba plug-in. Based on the determined network pharmacology, experimental validation was performed. Results: In this study, 45 active ingredients, 3162 potential drug targets and 343 pathway targets were uncovered via databases. The top 3 hub targets were obtained by the degree algorithm for 34 common target genes, including NFKBIA (encodes the IκBα protein), RELA (also named p65) and TNF. Molecular docking demonstrated that the core components fumarine, berberine and wogonin (Degree: 19, 16, 16, respectively) bind well to hub targets. In vivo experiments showed that EMS has better protective effects on adjuvant arthritis (AA) rats. In vitro studies demonstrated that EMS could inhibit the proliferation of TNF-ɑ-induced FLSs and attenuate the production of inflammatory cytokines in a dose-dependent manner. Moreover, treatment with EMS significantly decreased the ratio of p-NF-κB p65/NF-κB p65 and p-IκBα/IκBα in FLSs. Furthermore, as shown in the investigations, treatment of FLSs with 10% EMS remarkably suppressed TNF-ɑ-induced nuclear translocation of NF-κB p65 to FLSs. Conclusion: The potential mechanisms and therapeutic effects of EMS on RA may be attributed to the regulation of inflammation, which provides a reference for elucidating the mechanism of action of EMS.

Gene mutation detection and the resulted precision-medicine therapy is transforming clinical practice. Here, we report the use of a custom-developed, medium-sized, pan-cancer probe panel for the detection of somatic and germline mutations. We used a hybridization capture-based NGS assay for targeted deep sequencing of all exons and selected introns of 181 key cancer driver genes, covering both inherited risks and somatic mutations. We performed paired-variant calling on tumor samples and their matched normal samples. We processed clinical patient samples of formalin-fixed, paraffin embedded tumors (FFPE samples) and cell-free peripheral blood (cfDNA samples). We found germline mutations of inherited cancer risk at 9%; and discovered a novel germline mutation in BRCA1. Somatic mutation rate in driver genes is at 73.1%, much higher than previously reported. On recommending precision-medicine therapeutics, we achieved 91.6% for patients with FFPE samples.

Background: Atherosclerosis is the leading cause of cardiovascular disease worldwide, including in China. Primary prevention, through lipid-lowering, could avert development of atherosclerosis. Carotid intima-media thickness (CIMT) is a well-validated measure of atherosclerosis used in intervention studies as the primary outcome and alternative end point for cardiovascular disease events. Methods: This randomized, double-blind, placebo-controlled, multicenter, parallel-group study assessed the effects of rosuvastatin 20 mg/d compared with placebo on progression of CIMT over 104 weeks in Chinese people with subclinical atherosclerosis. The primary end point was the annualized rate of change in mean of the maximum CIMT measurements taken 7× over the study period from each of 12 carotid artery sites (near and far walls of the right and left common carotid artery, carotid bulb, and internal carotid artery). Secondary end points included CIMT changes at different artery sites and lipid-parameter changes. Safety was also assessed. Results: Participants were randomized (1:1) to receive rosuvastatin (n=272) or placebo (n=271). Baseline characteristics were well balanced between groups. The change in mean of the maximum CIMT of the 12 carotid sites was 0.0038 mm/y (95% CI, −0.0023–0.0100) for the rosuvastatin group versus 0.0142 mm/y (95% CI, 0.0080–0.0204) for the placebo group, with a difference of −0.0103 mm/y (95% CI, −0.0191 to −0.0016; P =0.020). For the CIMT secondary end points, the results were generally consistent with the primary end point. There were clinically relevant improvements in lipid parameters with rosuvastatin. We observed an adverse-event profile consistent with the known safety profile of rosuvastatin. Conclusions: Rosuvastatin 20 mg/d significantly reduced the progression of CIMT over 2 years in Chinese adults with subclinical atherosclerosis and was well tolerated. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02546323.

Microwave sterilization technology is an environmentally friendly non-incineration disposal method for medical waste. The core sterilization technology of "microwave sterilization, steam makes the system heat up quickly" was adopted to build a microwave sterilization screw conveyor system that can continuously and dynamically type microwave sterilization. The platinum resistance temperature sensor is used to measure the temperature of the steam at the outlet of the system and the temperature of the material at the outlet. The microwave sterilization process for medical waste was studied on the microwave sterilization test platform, and the influence and regularity of three factors on the microwave sterilization effect were explored and the microwave sterilization process was optimized using the orthogonal test method. Bacillus subtilis var. black spore (ATCC 9372) was used as the detection object of microwave sterilization effect, and the sterilization rate was calculated by the total number of colonies after culture. The results show that, microwave sterilization time has the greatest influence on sterilization effect, the greater the microwave power, the longer the sterilization time, the higher the water content, the higher the sterilization rate. The orthogonal test results show that the optimal process parameters of the microwave sterilization system are the microwave power of 22 kW, the sterilization time of 480 s, and the moisture content of 90%, the sterilization rate is 99.9996%, the sterilization effect is good. When the microwave power is 25 kW or 28 kW, the sterilization time is 480 s or 600 s, and the water content is 90%, the sterilization rate is 100%. Considering the germicidal effect, equipment cost, saving power consumption, shortening the germicidal process time and other comprehensive factors, this process parameter can obtain the best benefit. It can be seen that the use of microwave sterilization technology to treat medical waste is fast and efficient, and does not produce dioxins and other harmful substances, safe and environmental protection, simple operation, excellent sterilization effect.

In this work, an implantable and minimally invasive micro-aptasensor for adenosine monitoring in vivo, based on flexible integrated electrodes, was developed. Firstly the sensor was made by the modification of a needle-type electrode with reduced graphene oxide and gold nanoclusters (rGO-AuNCs) using two-step electrodeposition. Secondly Sulfhydryl-terminated capture probe (ssDNA1) was immobilized on rGO-AuNCs modified electrode surface by self-assembly, and then it was hybridized with adenosine aptamer (ssDNA2). Lastly methylene blue (MB) as an electrochemical indicator was adsorbed on the aptamer through specific interaction of MB with guanine base. The peak current of MB decreased linearly with increasing adenosine concentration due to the formation of aptamer-adenosine complex and displacement of the aptamer from the modified electrode surface. The sensor showed a low detection limit of 0.1 nM with signal-to-noise ratio equal to 3 as well as a wide linear response range (0.1 nM-1 mM) in vitro. Also, a high selectivity was demonstrated for adenosine in relation to uridine, guanosine, and cytidine. Experiments in vivo demonstrated fast responses for a range of adenosine concentrations. This work demonstrates a promising path for implantable devices for the determination of biomolecules in vivo, thus allowing for health tests, detection of infectious diseases, and other medical conditions.

We retrieved and analyzed the articles with the subject term words or key words of the "cupping spot" from January 1, 1990 to May 20, 2018. The negative pressure, cup-retaining time, temperature and the other factors about cupping spot were compared. There was a single stimulus for the negative pressure and cupping time. Pressure and time, pressure and temperature could be considered interactively, and the best group was on research. The color standard of canister spot diagnosis had not been unified, which could be analyzed from its color characteristic and color spectrum. At present, there is no agreement on the measurement of pressure and temperature, selection criteria of subjects, etc. The experimental researchmethods on the spot are becoming more and more diverse, with modern instruments for cupping spot on clinical efficacy and biological mechanism research.

An investigation was conducted of the ion current characteristics at various excess air ratios λ in a spark ignition engine fuelled with natural-gas–hydrogen blends. The Gaussian mathematical method was employed to fit the pure ion current signal without a spark tail generated by the ignition discharge. The cylinder pressure was recorded, and the Pauta criterion static threshold was used to deal with the outlier errors in the testing data for given cycles. The results show that the spark tail and the ion current can be separated by fitting the ion current with the Gaussian method, and the fitted pure ion current includes the flame-front stage and the post-flame stage. The timing with respect to the flame-front peak exhibits an irregular variation with λ. The maximum current in the flame-front stage increases with increasing λ.The timing of the maximum current in the post-flame stage occurs earlier at the stoichiometric ratio than at other air-to-fuel ratios. The correlation coefficient between the ion current in the post-flame stage and the pressure data treated with the Pauta criterion method increases. In addition, there are high correlation coefficients between the ion current and the pressure.

In this work, effects of direct-current (DC) electric fields on the flame propagation and combustion characteristics of premixed CH4/O2/N2 mixtures were experimentally investigated at excess air ratios of 0.8, 1.0, and 1.2, room temperature, and atmospheric pressure. Results show that the existence of the DC electric fields significantly affects the flame propagation and combustion properties. Specifically, the flame shape becomes a prolate spheroid, with the major axis in the electric field direction as a result of the movement of positive ions by the electric body force, and a further increase in the applied voltage distorts the flame front more significantly. Additionally, the flame propagation speed in the electric field direction (Sn) and corresponding unstretched laminar burning velocity (ul) are increased as the electric field becomes more intense, and this behavior is more pronounced for lean mixtures. Finally, the initial and main combustion durations defined by the pressure evolution profiles ar...

The relationship between ion current and local temperature was investigated with compressed natural gas (CNG) as a fuel. The ion current was measured using a pair of ignition electrodes and a pair of detector electrodes inside of a constant volume combustion bomb. The average temperature of the whole gas and the temperature at electrode gap were calculated using AVL-FIRE software. Meanwhile, flame development and pressure were recorded by a high-speed camera and a pressure sensor, respectively. The study indicates that, when ignition electrodes were used for detection, the current showed ignition, front-flame and post-flame stages. However, the ignition and part of the front-flame current were lost, when detector electrodes were used. The critical temperature for NO + generation and the appearance of post-flame current was about 2000 K. There were a linear relationship between the temperature and the number of NO + . With the increase in the distance between the two pair electrodes, the ion current and temperature decreased and the appearances of the front-flame and post-flame currents were postponed. The lower the temperature at the electrode gap was, the more obvious the influence of the contact area between the flame and the internal bomb wall on the post-flame current was.

Investigation on ionization current characteristic in a spark-ignition engine fueled with natural gas, natural gas–hydrogen bends and gasoline was conducted. Blind Source Separation (BSS) de-noising method is employed to separate the ionization current signal from the interference of spark tail generated by ignition discharge. Cylinder pressure was recorded, and local temperature at spark plug gap is calculated using AVL-FIRE simulation code. Results show that the simulated cylinder pressures are in good agreement with those of measured and the spark tail and ionization current can be separated using BSS method. Front flame stage and post flame stage in ionization current can be used to analyze the combustion characteristics of natural gas–hydrogen blends. De-noised current shows that the appearance of front flame stage and post flame stage (including the peaks in the stages) fueled with natural gas is postponed and compared with that fueled with gasoline, and the appearance of front flame stage and post flame stage advance with the increase of hydrogen fraction in natural gas–hydrogen blends. In addition, the amplitude of ionization currents in both front flame and post flame (including the two peaks) fueled with natural gas gives lower values compared with those fueled with gasoline and hydrogen addition can increase the amplitude. Maximum post flame current shows similar trend to maximum cylinder pressure and it has good correlation between the timing of maximum post flame current and the timing of maximum cylinder pressure. High correlation coefficient between maximum post flame current and maximum pressure is presented.

The metal hydride reactors are widely used in many industrial applications, for example, hydrogen storage, heat pump, thermal compression, gas separation, etc. The performance of the reactor is greatly affected by its design, which deserves careful study. Given the complicated nature of the hydride formation/decomposition processes, a series of technical issues are involved in the design of metal hydride reactors, such as primary configuration, thermal management, hydrogen transfer and mechanistic strength. These issues should be well addressed to fulfil the requirement of specific application. In this paper, the representative achievements with regards to the design issues so far were reviewed in detail, and some comments were made accordingly. It was concluded that an optimized reactor design comes from integrated considerations of numerous factors, particularly requirements for the applications and characteristics of the metal hydride system. The analytic hierarchy process was recommended for use in the selection of the optimum reactor scheme.

We developed a polymerase chain reaction (PCR) assay to detect Helicobacter pylori in gastric and/or gastroesophageal biopsy specimens of adults with dyspepsia, compared the method with immunohistochemical analysis and CLOtest (Ballard Medical Products, Draper, UT), and correlated the results of each test with the histologic features of infection. H pylori was identified in 36 (60%) of 60 patients irrespective of biopsy site and testing method. In the gastric biopsy specimens, PCR detected H pylori in 29 (52%) of 56 cases, including 11 (100%) of 11 immunohistochemically and/or CLOtest-positive cases. PCR-positive gastric biopsy specimens correlated with a higher average cumulative inflammatory score compared with PCR-negative specimens (P = .001). In gastroesophageal biopsy specimens, PCR detected H pylori in 15 (34%) of 44 cases, including 1 (20%) of 5 immunohistochemically positive specimens. PCR-positive gastroesophageal junction biopsy specimens did not correlate with a higher average cumulative inflammatory score. Overall, PCR detected an additional 23 cases negative by immunohistochemical analysis and/or CLOtest. This PCR assay identified a significant number of H pylori infections that would not be detected by immunohistochemical analysis and/or CLOtest.

In order to investigate the analgesic effect of needling at "Sitian" points for the nerve root-involved cervical spondylopathy, 68 cases of the nerve root-involved cervical spondylopathy were randomly divided into a treatment group of 46 cases treated by needling at "Sitian" points, and a control group of 22 cases treated by needling at cervical Jiaji points. After 2 therapeutic courses, the therapeutic effects were evaluated by using the visual analogue scale (VAS) and the semeiographic format. The results showed that the markedly effective rate was 78.3% and 54.5%, respectively in the treatment group and the control group, and the difference between the two groups was of significance (P0.05). It can be concluded that needling at "Sitian" points can bring about a better therapeutic effect on the improvement of clinical symptoms, physical signs and pain than that of the needling at the cervical Jiaji points.

Updated Sydney system graded from 0 to 3 based on morphologic parameters. Results: 39 of 41 (95%) patients with the R pattern were negative for HP infection with a Sydney score of 0. On the other hand 10/10 (100%) patients with the O pattern were HP positive. 15/23 (65%) of the I pattern were HP positive. The sensitivity, specificity, positive predictive value and negative predictive value of the ‘‘R’’ pattern as indicator for absence of infection were 85.45%, 93.10%, 95.92% and 77.14% respectively. The sensitivity, specificity, PPV and NPV of the ‘‘O’’ pattern for the presence of infection were 61.36%, 100%, 100% and 73.4%. The Updated Sydney scores for the ‘‘I’’ and ‘‘O’’ pattern were significantly higher than the R pattern (p ! 0.01). Conclusion: The pattern and visibility of the microvascular network of the corpus is influenced by HP induced gastritis. NBI can reliably predict HP induced gastritis as well as HP free status. High resolution narrow band imaging could be a potential tool for the instantaneous real time diagnosis of HP infection.