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An outbreak of a novel coronavirus was reported in Wuhan, China, in late 2019. It has spread rapidly through China and many other countries, causing a global pandemic. Since February 2020, over 28 countries/regions have reported confirmed cases. Individuals with the infection known as coronavirus disease-19 (COVID-19) have similar clinical features as severe acute respiratory syndrome first encountered 17 years ago, with fever, cough, and upper airway congestion, along with high production of proinflammatory cytokines (PICs), which form a cytokine storm. PICs induced by COVID-19 include interleukin (IL)-6, IL-17, and monocyte chemoattractant protein-1. The production of cytokines is regulated by activated nuclear factor-kB and involves downstream pathways such as Janus kinase/signal transducers and activators transcription. Protein expression is also regulated by post-translational modification of chromosomal markers. Lysine residues in the peptide tails stretching out from the core of histones bind the sequence upstream of the coding portion of genomic DNA. Covalent modification, particularly methylation, activates or represses gene transcription. PICs have been reported to be induced by histone modification and stimulate exudation of hyaluronic acid, which is implicated in the occurrence of COVID-19. These findings indicate the impact of the expression of PICs on the pathogenesis and therapeutic targeting of COVID-19.

To explore the anti-inflammatory effect and the potential mechanism of dexmedetomidine in ARDS/ALI.C57BL/6 mice and EL-4 cells were used in this research. The ALI model was established by CLP. The level of inflammatory cytokines in the lung and blood, the severity of lung injury, the expression of Foxp3, and the proportion of Tregs were detected before and after dexmedetomidine treatment. The expression of the AMPK/SIRT1 after dexmedetomidine treatment was detected in vivo and in vitro. After blocking the AMPK/SIRT1 pathway or depleting Tregs in vivo, the level of the inflammatory response, tissue injury, and Tregs differentiation were detected again to clarify the effect of dexmedetomidine.Dexmedetomidine significantly reduced systemic inflammation and lung injury in CLP mice. Dexmedetomidine enhanced the Foxp3 expression in the lungs and the frequency of Tregs in the spleen. Dexmedetomidine up-regulated the protein expression of p-AMPK and SIRT1 in lungs and EL-4 cells and facilitated the differentiation of naïve CD4DEX could improve ARDS/ALI by facilitating the differentiation of Tregs from naïve CD4

BACKGROUND Dieulafoy’s lesion is a rare vascular abnormality characterized by a small abnormally dilated artery that runs a tortuous course in the submucosa. There is usually no ulcer present in Dieulafoy’s lesions and the overlying mucosa is most often normal. Bleeding caused by a Dieulafoy’s lesion is usually urgent, massive, life-threatening and prone to recurrence. Dieulafoy’s lesions have been reported throughout the digestive tract although the majority of them have been found in the upper digestive tract especially the stomach and duodenum. However, a Dieulafoy’s lesion occurring inside a duodenal diverticulum is very rare. CASE SUMMARY A 74-year-old Asian male with epigastric pain, hematemesis and melena was admitted to our clinic. Before admission, the patient had vomited 500 mL of dark red blood, and passed 200 g of black tarry stool. Conservative management was first undertaken as the patient had not been fasting. However, hemorrhage recurred and the patient went into shock. Urgent endoscopy was performed and a diverticulum of 1.8 cm × 1.2 cm × 0.8 cm was found on the anterior wall of the descending duodenum. The diverticulum was covered with a blood clot. After the clot was removed, an artery stump was observed in the diverticulum with a diameter of 2-3 mm. Two titanium hemostatic clips were inserted to clamp the vessel stump. The patient was discharged 7 d post-endoscopy and followed for 6 mo with no recurrence. CONCLUSION This case was diagnosed with a Dieulafoy’s lesion inside a duodenal diverticulum which has rarely been reported. Hematemesis was stopped by clamping the vessel stump with titanium clips. No complications occurred.

Effect of various silicon sources, such as TEOS, MTES mixed with TEOS and 1,3,5-tris(triethoxymethyl) on SiO2 films was investigated. The synthesized solutions were used as silicon sources to prepare silica-like backbone films. The investigation showed that all precursors can able to produce the flat and uniform films. An FTIR spectrum confirmed the formation of SiO2 in film matrix. The results indicated that the internal microstructure of each film is different. The incorporation of less polar bonds such as F and C was carried out using various Si sources, while the introduction of these sources confirmed through FTIR spectra. Optical properties of the films were carried out by using ellipsometric porosometry (EP) measurement. The leakage current density for the films prepared by using TEOS, MTES and 135TTEB was observed to be 2.8 × 10-7 A/cm2, 2.9 × 10-8 A / cm2, and 4.1 × 10-6 A / cm2, respectively, at 1 MV/cm electric field strength by the IV curves obtained by semiconductor characterization after fabricating MIS devices. The calculated dielectric constants from RI of the deposited SiO2 films were 2.0, 1.9 and 2.5 respectively. When the microstructure of the precursor solution changed, the introduction of atomic morphology or terminal inerted group ratio changed the internal bridging mode of SiO2, and thereby significantly reduced the dielectric constant and improved insulation.

Based on the generalized bilinear operators in a prime number p = 3, we introduce a (2+1)-dimensional coupled nonlinear partial differential like equation. By combining an exponential function with a quadratic function, an interaction between a lump wave and a one-kink soliton is generated. In addition, an interaction between a lump wave and a two-kink soliton, which is called a special rogue wave, can be obtained by adding two additional exponential functions. The dynamic properties of these interactions are depicted by selecting appropriate parameters.

Brachial plexus avulsion often results in massive motor neuron death and severe functional deficits of target muscles. However, no satisfactory treatment is currently available. Hypoxia-inducible factor 1α is a critical molecule targeting several genes associated with ischemia-hypoxia damage and angiogenesis. In this study, a rat model of brachial plexus avulsion-reimplantation was established, in which C5-7 ventral nerve roots were avulsed and only the C6 root reimplanted. Different implants were immediately injected using a microsyringe into the avulsion-reimplantation site of the C6 root post-brachial plexus avulsion. Rats were randomly divided into five groups: phosphate-buffered saline, negative control of lentivirus, hypoxia-inducible factor 1α (hypoxia-inducible factor 1α overexpression lentivirus), gel (pluronic F-127 hydrogel), and gel + hypoxia-inducible factor 1α (pluronic F-127 hydrogel + hypoxia-inducible factor 1α overexpression lentivirus). The Terzis grooming test was performed to assess recovery of motor function. Scores were higher in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor 1α groups (in particular the gel + hypoxia-inducible factor 1α group) compared with the phosphate-buffered saline group. Electrophysiology, fluorogold retrograde tracing, and immunofluorescent staining were further performed to investigate neural pathway reconstruction and changes of neurons, motor endplates, and angiogenesis. Compared with the phosphate-buffered saline group, action potential latency of musculocutaneous nerves was markedly shortened in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor 1α groups. Meanwhile, the number of fluorogold-positive cells and ChAT-positive neurons, neovascular area (labeled by CD31 around avulsed sites in ipsilateral spinal cord segments), and the number of motor endplates in biceps brachii (identified by α-bungarotoxin) were all visibly increased, as well as the morphology of motor endplate in biceps brachil was clear in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor 1α groups. Taken together, delivery of hypoxia-inducible factor 1α overexpression lentiviral vectors mediated by pluronic F-127 effectively promotes spinal root regeneration and functional recovery post-brachial plexus avulsion. All animal procedures were approved by the Institutional Animal Care and Use Committee of Guangdong Medical University, China.

C14orf166, a 28 kD protein regulating RNA transcription and translation, may serve a critical role in oncogenesis. The aim of the current study was to explore the association between C14orf166 expression and esophageal squamous cell carcinoma (ESCC) and to draw attention to the association between C14orf166 and the initiation, progression and prognosis of ESCC. C14orf166 expression in ESCC and paired normal tissues was detected by immunohistochemical staining, western blotting and reverse transcription-quantitative polymerase chain reaction, and the association between C14orf166 expression and clinicopathological characters of ESCC was analyzed. Survival analysis was used to assess the prognostic significance of C14orf166 and it was observed that C14orf166 expression was higher in the ESCC tissues when compared with adjacent non-cancerous tissues at protein (P

Graphite nanoplatelets were prepared by a novel magnetic-grinding method using self-made equipments. Under a variant magnetic field, magnetic needles collided at a high rotating speed and exfoliated pristine graphite into graphite nanoplatelets with high efficiency. The obtained graphite nanoplatelets are highly crystalline, and the thickness is less than 10 nm. Moreover, the surface area could reached 738.1 m2/g with a grinding time of 4 h. Silanized graphite nanoplatelets can disperse well in SG 15W-40 engine oil and serve as lubricant additive. Tribological results indicate that the friction coefficient and wear-scar of the friction pairs are lower than 76% and 41%, respectively, by adding 1.5‰ (mass fraction) of silanized graphite nanoplatelets. Notably, the functionalized graphite nanoplatelets can realize large-scale production and commercial application.

A method of fabricating convex plate-shaped micro electrode was proposed based on the electrochemical etching principle. The square sectional electrodes were prepared in advanced using wire-EDM, The micro cylindrical electrode was fabricated firstly by using the eletrochechemical etching method. Then the top end was insulated to protect it from etching. Then the convex plate-shaped micro electrode was obtained in subsequent etching. Comparative experiments in drilling micro-hole in stainless steel with the thickness of 1mm were done by using the cylindrical and convex plate-shaped micro electrode. Results shows that the better locality, smaller side-gap and hole taper could be obtain by using convex plate-shaped micro electrode.

With continuous improvement and update of embedded Linux kernel, embedded technology has been widely used in handheld devices and industrial control field. Therefore, a user-friendly graphical user interface (GUI) is essential for these applications. This paper firstly presents the design method for transplanting Qt on embedded platform of ARM9. Secondly it elaborates the device driver development and Qt interface development in Linux system with a Qt test program. All transplantation method of Qt and test program have been tested and verified on the ARM9 platform.

In this paper, 0.05 grade three-phase main control system of multi-station meter testing equipment (MTE) is presented. This design is based on the S3C2440 core board as the control core, and the software is based on Windows CE(WINCE) embedded operating system. The device is displayed and controlled by 7-inch Touch Screen. The main control system communicate with the error instrument and PC through Controller Area Network (CAN) bus, and the largest number of error instruments can connect to CAN bus is 100. The main control system communicates through RS232 bus with three-phase signal source and standard electric energy meter, through RS485 bus with programmable power amplifier. In this device, calibration of energy meters can not only through the PC software, but also use the main control system. Compared to the traditional design of the electric energy meter calibration device, the design’s the man-machine interface is more optimized, the number of electric energy meters can be test in the same time is more, faster communication, stronger anti-interference ability, and calibration is more efficiency.

The preparation of mesoporous SiO2 with electric field (EF) induced different molecular templates method was reported. The effect of EF on the microstructure of the material has been investigated by scanning electron microscopy and static nitrogen adsorption analyzer. Results showed that the molecular regularly arranged by high voltage electrostatic field could effectively affect the porosity of the samples. The dielectric constant estimated from the Rayleigh and Lorentz-Lorenz classic models, was1.90.

The deep levels of carbon doped high resistivity (HR) GaN samples grown by metal-organic chemical vapor deposition (MOCVD) has been investigated using thermally stimulated current (TSC) spectroscopy and high temperature (HT) Hall measurement. Two different thickness of 100 and 300 nm were used to be compared. It was found that four distinct deep levels by TSC and one deep level by HT Hall measurement were observed in both samples, which means great help for the decrease of leakage current and lifetime limitations of device utilizing the structure. The activation energy of these levels was calculated and their possible origins were also proposed. The low temperature traps, might be related to VN, 0.50 and 0.52eV related to incorporate a high level carbon, 0.57eV related to VGa, 0.59eV related to CGaor NGa, 0.91 and 0.97eV related to interstitial N1.

This paper is about how to design an improved anti-ribboning method for the winder system. The system is based on the principle of a brushless DC motor control, which constantly changes relative velocity between the grooved drum and the yarn bobbin. This in turn, causes the changing of the winding ratio value. Therefore, it will accomplish the anti-ribboning control. Compared with the traditional anti-ribboning methods, the improved method can save more mechanical components and maintenance costs. Also, this method can develop different programs for different yarns. Therefore, this method is more efficient and versatile.

In order to improve the step accuracy of two-phase hybrid stepping motors, this paper presents a high-performance stepping motor driver based on controllable dead-time compensation. After CPLD(Complex Programmable Logic Device) logical processing, the subdivision drive signal created by microcontroller STM32 becomes a complementary dead-time compensation drive signal which can realize precise control of stepper motor. The experiment shows that this program not only has effectively reduced the power consumption of the stepping motor, but also made whole system cost less.

In this paper, a gas stove and range hood integrated intelligent control system based on wireless communication is introduced. This system enables range hood running through wireless communication without human intervention, and gas stove can directly and automatically control the opening, the wind speed and closed of range hood. Compared to traditional gas stove and range hood, it implements the gas stove and range hood work together to make the operation more safe, convenient and fast. Through experimental test, the proposed design is feasible to achieve the gas stove and range hood integrated intelligent control system design requirements.

In this paper, a kind of variable frequency and multi-pressure water supply control system based on STM32 processor is designed. It can adjust the water pressure dynamically, according to the changes of water flow. Therefore, it can economize the energy consumption significantly. In order to improve real-time performance, the system adopts STs STM32F407 series processor which is based on ARM® CortexTM-M4 32-bit RISC core. It is used to collect the water flow, pressure and other data in real time, and automatically adjust the output frequency to control the motor speed, according to the set pressure value, and ultimately control the flow and pressure of the water supply system. According to the test, this variable frequency and multi-pressure water supply control system based on STM32 processor can meet the design requirements.

A (2[Formula: see text]+[Formula: see text]1)-dimensional high-order nonlinear evolution (HNE) equation is considered in this paper. A Hirota bilinear form of the HNE equation is constructed by the dependent variable function. Solitary waves are derived by solving the Hirota bilinear form of the HNE equation. Lump waves of the HNE equation are obtained by introducing a positive quadratic function. By mixing an exponential function or two exponential functions with a quadratic function, interaction solutions between a lump and a one-soliton, and between a lump and a two-soliton are presented. For the interaction solution between a lump and a two-soliton, this kind of solution can be considered as a special rogue wave. The propagation phenomena of these explicit solutions are illustrated by some graphs.

Water-soluble fluorescent carbon dots (CDs) have been synthesized in one step by hydrothermal treatment of potato. Effects of the hydrothermal treatment time, temperature, potato additive amount and pH on the light emissions of the CDs were also studied. HRTEM images of the CDs showed spherical particles with fairly uniform diameter of approximate 2~3 nm, which also dispersed excellently in water. The characteristic absorption peak of CDs appeared at about 280 nm and exhibits a strong bright blue light emission with a high quantum yield (14.2%). The mechanism of the fluorescent emission from CDs was proposed. Moreover, some highly fluorescent CDs were also prepared with other vegetables under the same condition.

We have designed a photoelectric yarn signal acquisition system, which is based on the STM32 processor, having a sample rate up to 270kHz, and uploading data collection through synchronous parallel communication mode; Owing to the large noise of yarn signal and the unobviousness of yarn defect, we respectively adopting wiener filter and mean filter to filter this signal; The simulation result of matlab has manifested that both the wiener filter and mean filter can effectively decrease the noise level of the yarn signal and make the nep defects easier to identify, and that the wiener filter applies to application where the yarn speed is higher , while the mean filter is appropriate to the lower speed spinner.

According to the size and connecting characters of soil particles, soil is discomposed into two components as matrix and reinforcement particles respectively with a demarcation size fixed at 0.075mm to investigate the influence of the microstructures on soil strength. Based on the strain gradient theory, a multi-scale matrix-reinforcement particle model was established to study the trans-scale properties of soil strength which indicates that the soil strength is related to the intrinsic length scale, the strain gradient, the matrix properties and the gradation and size of reinforcement particles. A series of consolidated and undrained compression tests of unsaturated remoulded soil were designed to study the trans-scale properties of soil strength. The results showed that: the yield stress of soil increased as the reinforcement particle size decreased, displaying the trans-scale properties of soil strength. The research result is significant to the development of strength theory of soil.

Calcium phosphate cement (CPC) has been widely used in orthopedic and dental applications. A critical limitation of CPC is low strength and high susceptibility to severe fracture. Surgeons can use it only to reconstruct non-stress bearing bone, raising the need for a tougher new generation of CPC. Fibers have been used as a reinforcement of CPC to improve the strength of a pure CPC scaffold. The RGD peptides (Arg-Gly-Asp) have been used to improve the biocompatibility of the scaffold, via physical adsorption. The purpose of this study was to develop a novel CPC scaffold reinforced by RGD peptide-bearing chitosan fibers (RGD-fiber-CPC). Our data showed that the RGD-fiber-CPC scaffold had an increased flexural strength, and stimulated new bone formation in an animal model. The RGD-fiber-CPC is a novel bone graft substitute in orthopedic surgery. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 68–75, 2014.

A number of studies have indicated that Nurr1, which belongs to a novel class of orphan nuclear receptors (the NR4A family), is important for carcinogenesis. Here we investigated expression of Nurr1 protein in benign and malignant human prostate tissues and association with clinicopathologic features using immunohistochemical techniques. Moreover, we also investigated the ability of Nurr1 to influence proliferation, migration, invasion and apoptosis of human prostate cancer cells using small interfering RNA silencing. Immunohistochemical analysis revealed that the expression of Nurr1 protein was higher in prostate cancer tissues than in benign prostate tissue (P < 0.001), levels being positively correlated with tumor T classification (P = 0.003), N classification (P = 0.017), M classification (P = 0.011) and the Gleason score (P = 0.020) of prostate cancer patients. In vitro, silencing of endogenous Nurr1 attenuated cell proliferation, migration and invasion, and induced apoptosis of prostate cancer cells. These results suggest that Nurr1 may be used as an indicator for prostate cancer progression and be useful for novel potential therapeutic strategies.

CPUs in embedded systems sometimes have limited performance for the sake of cost, so there may be impossible for these systems to drive a LCD display with a high frame rate. An FPGA based schema is proposed to increase the frame rate of the LCD display so that the texts etc. can be seen fluently. The frame rate enhancer is composed of three parts, an FPGA for receiving the data to be displayed, an SDRAM for data storage and an LCD controller for display control. The designed frame rate enhancer can be used in an embedded system, which has a large LCD display but a low performance CPU, without any flicker.