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Purpose: To investigate the effect of miR-486 on rats with acute myocardial infarction (AMI), and its mechanism of action.Methods: A rat model of AMI was established. They were randomly divided into 4 groups, namely, sham, model, agomiR-486 and antagomiR-486 groups, respectively. Rats in these different groups were treated with agomiR-21 (5 μL, 40 nmol/mL), antagomiR-21 (5 μL, 40 nmol/mL) or agomiR-NC (5 μL, 40 nmol/mL), respectively. Then, key miRNAs were sorted out using gene-chip assay and verified by quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. Luciferase reporter gene assay was conducted to determine the interaction between miR-486 and gene of PTEN. After intraperitoneal injection of agomiR-486 and antagomiR-486, hemodynamics was measured to determine the effect of miR-486 on myocardial function of the rats. The effect of miR-486 expression level on the expression of myocardial enzymes in serum, the morphology of myocardial tissues, and the apoptosis of myocardial tissues in rats, were investigated. Additionally, the effect of miR-486 expression level on PTEN/AKT signaling pathway in the rats was determined by Western blotting.Results: The results of gene-chip and qRT-PCR assays revealed that there were 8 differentially expressed genes in rat myocardial tissues in the model group when compared with the sham group. MiR-486 improved the cardiac function of rats and the morphology of myocardial tissues, but reduced AMI-induced apoptosis of myocardial cells and the expression of myocardial enzymes (markers of myocardial injury) in a dose-dependent manner (p < 0.05). The results of luciferase reporter gene assay showed that PTEN was a direct target of miR-486. In rat models of AMI, a raised expression of miR-486 remarkably suppressed the protein expression level of PTEN and up-regulated that of p-AKT/AKT (p < 0.05).Conclusion: MiR-486 protects against AMI in rats probably by targeting PTEN and activating the AKT signaling pathway. The results of the current study may provide new insights for the treatment of AMI.

Using Northeast China as the research area and three time nodes (2007, 2012, and 2017), the gravitational model and Euclidean distance method were used to measure the spatial economic connections and geoeconomic relations between four regional central cities and other small- and medium-sized cities. The complexity of urban economic relations was systematically analyzed based on matching urban economic connections and geoeconomic relations. This paper provides suggestions on how to strengthen and build a benign and sustainable urban economic relations system in Northeast China. The results of the study show that, from 2007 to 2017, the economic links between the four central cities and other cities continued to strengthen. Shenyang had the highest total of economic links, and Changchun, the fastest growth rate. From 2007 to 2017, the geoeconomic relations between the four central and other cities generally improved, shifting from competitiveness to complementarity. Competition intensified for Shenyang and Dalian with cities in Liaoning province, and their complementarity strengthened with cities outside the province. The relationship between the four central cities with other cities is to strengthen cooperation and complementarity. Therefore, the cities in Northeast China need to strengthen economic ties and the complementarity of geoeconomic relations and optimize the matching relationship. They should focus on the role of regional central cities in promoting the economic integration of the entire Northeast China and jointly promote the orderly urban niche system and full coordination. The formation and stability of the developing regional cooperative community are discussed.

In this paper, the tested chip was directly immersed in subcooled (ΔTsub = 3 K) FC-72 for boiling heat transfer, and an experimental apparatus with suction tube was designed. A smooth silicon chip with the dimension of 10 × 10 × 0.5 mm3 (length × width × thickness) was used as a heater. The effects of inner diameter of suction tube (D = 2.2, 5.5 and 9.6 mm) and the distance from the suction tube inlet to the tested chip surface (H = 1, 3 and 5 mm) on boiling heat transfer performance were explored. For comparison, experiment without suction on a smooth surface was also conducted. The experimental results showed that the suction boiling has a significant heat transfer enhancement compared with the traditional pool boiling without suction. The suction tube with the diameter of 5.5 mm has the best boiling heat transfer performance, and then 9.6 mm followed by 2.2 mm under the same variables, and the suction distance of 1 mm shows the largest heat transfer enhancement. The heat transfer coefficient (HTC) increases with the decrease of the distance from the suction tube inlet to the tested heating surface. At D = 5.5 mm and H = 1 mm, the maximum critical heat flux (CHF) increased by 39.22% compared with pool boiling without suction, while the maximum CHF increased to 33.4 W·cm−2, and the maximum HTC increased by 79.77% compared with pool boiling without suction, while the maximum HTC increased to 1.093W·cm−2·K−1. The mechanism of the enhancement of the boiling heat transfer performance is attributed to that the liquid supplement is enhanced and the bubbles departure velocity is accelerated due to the local low pressure and shear lift force generated by the suction.

In material research, it is often highly desirable to observe images of whole microscopic sections with high resolution. So that micrograph stitching is an important technology to produce a panorama or larger image by combining multiple images with overlapping areas, while retaining microscopic resolution. However, due to high complexity and variety of microstructure, most traditional methods could not balance speed and accuracy of stitching strategy. To overcome this problem, we develop a method named very fast sequential micrograph stitching (VFSMS), which employ incremental searching strategy and GPU acceleration to guarantee the accuracy and the speed of stitching results. Experimental results demonstrate that the VFSMS achieve state-of-art performance on three types’ microscopic datasets on both accuracy and speed aspects. Besides, it significantly outperforms the most famous and commonly used software, such as ImageJ, Photoshop and Autostitch. The software is available at https://www.mgedata.cn/app_entrance/microscope .

Abstract:The battery health plays a key and decisive role in the use of lithium batteries. In this paper, the battery data detected offline is used to predict SOH through the big data platform algorithm model, in order to acknowledge the current health of the battery. The construction of the learning model is carried out through the historical data of 1000 batteries data set, so that the MAE(mean absolute error) is lower than 0.095%.

In this paper, we propose an multi-scene automatic monitoring system based on edge cloud cooperation, which uses multiple high sampling-rate robotic total stations and reflectors to observe in multiple directions, and the data information is transmitted to the edge nodes in real time. The embedded gateway device is deployed at the edge of the network, which provides lightweight connection management through network connection, protocol conversion and other functions to realize the device connection to the cloud. Data is uploaded to the cloud through differential processing. The cloud provides cloud applications, cloud services and cloud storage, and analyzes, processes, stores and real-time monitoring and warning of the collected information. After actual testing, the system can achieve continuous, real-time and high-precision collection deformation data and early warning.

In this study, Mtb8.4 and HspX, which are expressed at proliferating and dormant stages of Mycobacterium tuberculosis (M. tuberculosis), respectively, were chosen to construct two fusion proteins, Mtb8.4-HspX (8.4H) and HspX-Mtb8.4 (H8.4), and we investigated whether the antigen dose and protein sequential order could impact the immunogenicity and protective efficacy of these fusion protein vaccines against M. tuberculosis. C57BL/6 mice were vaccinated with new constructions containing a fusion protein with adjuvant of N, N'-dimethyl-N, N'-dioctadecylammonium bromide (DDA) or a mixed adjuvant composed of DDA, polyribocytidylic acid and gelatin (DPG), and the antigen specific immune responses and protective efficacy against M. tuberculosis H37Rv were evaluated. The results showed that both antigens, Mtb8.4-HspX and HspX-Mtb8.4, could elicit strong human T cell responses. With the existing of DDA adjuvant, HspX-Mtb8.4 induced significantly higher secretion level of IFN-γ and TNF-α in spleen cells than Mtb8.4-HspX (p

Guanine-rich DNA sequences can undergo self-assembly into unique G-quadruplex structures that interfere with the binding of proteins to the same DNA region. The formation of DNA G-quadruplexes requires monovalent cations (Na+ and K+) or small molecules known as G-quadruplex (G4) ligands. Phenanthroline is a type of G4 ligand scaffold known for its coordination with metal ions to form complexes with a large aromatic surface area, which aptly stack with G-quartets. In this report, we have investigated the side chain effect on G-quadruplex recognition by evaluating a series of 5-substituted phenanthroline-based metal complexes (Phen-Ni) binding to telomeric G-quadruplex DNA. Results from biophysical methods including fluorescence and circular dichroism (CD) thermal denaturation, CD titration, and the fluorescent intercalator displacement (FID) assay suggest that several Phen-Ni complexes bind to G-quadruplex DNA with submicromolar G4DC50 values. Arylsulfanyl groups at the 5 position of 1,10-phenanthroline are the best side chains regarding binding affinity and selectivity towards G-quadruplex DNA. Most of the G-quadruplex binding Phen-Ni complexes can inhibit telomerase activity in vitro as indicated by the telomeric repeat amplification protocol (TRAP) assay and such inhibition is clearly concentration dependent. Our results here provide a guidance of utilizing 5-substituted phenanthroline derivatives as a viable and facile approach to design novel G4 ligands.

Quantitative analysis through image processing is a key step to gain information regarding the microstructure of materials. In this paper, we develop a deep learning-based method to address the task of image segmentation for microscopic images using an Al–La alloy. Our work makes three key contributions. (1) We train a deep convolutional neural network based on DeepLab to achieve image segmentation and have significant results. (2) We adopt a local processing method based on symmetric overlap-tile strategy which makes it possible to analyze the microscopic images with high resolution. Additionally, it achieves seamless segmentation. (3) We apply symmetric rectification to enhance the accuracy of results with 3D information. Experimental results showed that our method outperforms existing segmentation methods.

An Electroencephalogram (EEG)-based Brain Computer Interface (BCI) system is put forward to implement the continuous control of an Unmanned Aerial Vehicle (UAV) in the indoor 2D space using the motor imagery (MI) tasks. This BCI system utilizes the discriminative time- and frequency-dependent spatial filter to extract the EEG features of MI tasks. The adaptive linear discriminant analysis (LDA) method is utilized to accomplish the classification of these extracted features. The calibration experiment and actual indoor 2D space controlling experiment presented the effectiveness and feasibility of using this BCI system to achieve the indoor 2D space continuous control of UAV.

Hepatoblastoma (HB) is the most common primary malignant tumor of the liver in young children. The aim of this study is to identify the diagnostic and prognostic values of serum exosomal miR-21 in Chinese patients with HB. We retrospectively reviewed 32 children with HB. The expressions of miR-21 were detected by real-time PCR. The comparison of diagnostic performance of plasmatic, exosomal miR-21 and AFP levels was measured using the Area Under ROC Curve. For patients in HB group, miR-21 concentration was significantly higher in the exosomes compared with the exosome-depleted supernatants and whole plasma. Expression of miR-21 was significantly higher in patients with HB compared with control group in both plasma and exosomes. With respect to the diagnosis of patients with HB, exosomal miR-21 was significantly more accurate compared with the Alpha-fetoprotein levels. Moreover, exosomal miR-21 was an independent predictor of Even-free survival for patients with HB. In this study, we found that expression of miR-21 was significantly higher in patients with HB compared with control group in both plasma and exosomes, and we confirmed that exosomal miR-21 could be defined as a diagnostic and prognostic biomarker for patients with HB.

Native DNA lesions in general destabilize DNA secondary structures such as duplex and G-quadruplex because they disrupt optimized interactions in DNA defined by nature. In this paper, we report the first example of a native DNA lesion (8-oxo-7,8-dihydrodeoxyadenosine, OxodA) that stabilizes human telomeric G-quadruplex DNA. CD thermal denaturation studies explicitly displayed increased melting temperatures of telomeric G-quadruplex DNAs that contain OxodA(s) in different DNA loops, suggesting enhanced thermal stability. Conformation studies of G-quadruplex DNAs containing OxodA(s) in the loops using CD and native PAGE revealed that they adopt a similar antiparallel conformation in Na + but have much more versatile conformations in K + . According to computational calculations, the observed stabilization may result from the tight binding of K + into the pocket formed by the O8 of OxodA and its loop. The study reported here may provide better understanding of the effect of DNA lesions on G-quadruplex stability and conformation.

In this study, calix[4]arene derivatives (11–14) bearing a single nucleobase (adenine, thymine, cytosine or guanine) were synthesised via click chemistry. The complexation ability of the synthesised derivatives with alkali metal ions was measured using MALDI-TOF mass spectrometry, and their molecular assembly in CDCl3 was determined using 1H NMR. Calix[4]arene derivatives (11–14) formed 1:1 complexes with all alkali metal ions and the rank order for the complexation selectivity was Rb+ > Cs+ > K+ ≅ Na+ > Li+. The attachment of nucleobase at the upper rim of calix[4]arene had little effect on its complexation selectivity for alkali metal ions. Thymine-, adenine- and guanine-calix[4]arenes formed self-assembled structures in CDCl3 via base–base interactions. In addition, adenine-calix[4]arene (11) bound to thymine-calix[4]arene (12) to form a discrete species via Hoogsteen hydrogen bonding.

A thymine and acridine conjugate (1), containing a benzylic carbon of thymine and an electron-rich aromatic ring (acridine) within the same molecule, was synthesized. Treatment of 1 with N-bromosuccinimide (NBS) in anhydrous chloroform in the presence of azobisisobutylnitrile produced a dibromo-substituted thymine–acridine conjugate (7) as a major product, in which the bromination was only observed on the acridine ring. Nuclear Overhauser effect (NOE) difference spectroscopy revealed that the actual bromination substitution was on C-2 and C-7 of acridine. Our results suggest that electrophilic aromatic substitution, not the expected benzylic radical reaction, takes place predominantly even when 1 is subjected to the NBS reaction condition, which favors radical processes. In addition, such selectivity is clearly solvent dependent.

The level of mycotoxin fumonisins in corn-based food and feed collected from Linxian County, a high-risk area for esophageal cancer in China, has been analyzed using high-performance liquid chromatographic coupled with evaporative laser scattering detector (HPLC-ELSD). A total of 104 corn kernel samples were obtained from local households, granaries, wholesale markets (central markets), and retail markets (stores and supermarkets). Fumonisin B 1 (FB 1 ) was detected in the samples from households, granaries, central markets, and stores, with a positive rate of 61.5%, 50%, 33.3%, and 17%, respectively. No fumonisin was detected in samples from the supermarket. The highest FB 1 levels (0.30–3.20 μg/g; mean, 1.42 μg/g) were found in samples from the granary, followed by household (0.25–1.80 μg/g; mean, 0.73 μg/g), central market (0.25–1.10 μg/g; mean, 0.51 μg/g), and store (0.22–0.34 μg/g; mean, 0.28 μg/g). Among the 80 corn kernel samples collected from local households, 18 of 24 (75.0%) moldy samples contained high levels of FB 1 (0.28–3.30 μg/g; mean, 1.58 μg/g), and 20 of 56 (35.7%) apparently healthy samples contained low levels of FB 1 (0.21–0.82 μg/g; mean, 0.46 μg/g). As the central market plays an important role in trade of corn-based food and feed in China, a total of 115 corn-based food and feed samples were collected from the local central market. The highest FB 1 levels (0.30–3.13 μg/g; mean, 1.50 μg/g) were found in feed, followed by unprocessed food (0.31–0.63 μg/g; mean, 0.47 μg/g) and processed food (0.21–0.28 μg/g; mean, 0.25 μg/g). The positive incidence of FB 1 in feed, unprocessed, and processed food were 53.6%, 33.3% and 17.9%, respectively. In conclusion, the results showed that corn-based food and feed from Linxian County contained low level of FB 1 (

The Power Input Method (PIM) is used both experimentally and a nalytically to estimate the system loss factor for sandwich panels with various configurations of Constrained Layer Damping (CLD) treatments over a broad frequency range. The experimental power input method is applied to both uniformly and non -uniformly da mped structures. Results are compared with results from other experimental methods. A new analytical power input method is proposed for evaluating the loss factor of built -up structures, based on the finite element model with assigned properties of the con stituents. The new analytical power input method is evaluated by comparison with the commonly used Modal Strain Energy (MSE) method. Instead of making an approximate correction of the constant material properties, this analytical power input method directl y takes into account the frequency -dependent material properties of the viscoelastic material using the MSC/NASTRAN direct frequency response solution. Results of experimental and analytical methods are presented, compared and discussed. It is shown that: 1) all three currently available experimental methods yield consistent results, while the power input method gives damping estimation other than just at several discrete frequencies basically in the low frequency range; 2) both the analytical power input m ethod and the modal strain energy method yield consistent results with the experimental power input method. Furthermore, both experimental and analytical power input methods are used to investigate how loss factors change as the excitation position change. This shows another merit of the analytical power input method, because analytical modal methods cannot take into account the change of excitation position.

In this paper, we investigate a classical periodic Lotka–Volterra competing system with impulsive perturbations. The conditions for the linear stability of trivial periodic solution and semi-trivial periodic solutions are given by applying Floquet theory of linear periodic impulsive equation, and we also give the conditions for the global stability of these solutions as a consequence of some abstract monotone iterative schemes introduced in this paper, which will be also used to get some sufficient conditions for persistence. By using the method of coincidence degree, the conditions for the existence of at least one strictly positive (componentwise) periodic solution are derived. The theoretical results are confirmed by a specific example and numerical simulations. It shows that the dynamic behaviors of the system we consider are quite different from the corresponding system without pulses.

Existing methods for wing weight estimation are compared and steps to refine and expand the procedure are proposed. Results show that the refined procedure yields more accurate wing weight estimation. Literature on wing Center of Gravity (C.G.) estimation is scarce and existing methods are only empirical span and chord percentages. A new procedure is proposed, discussed and verified. C.G. results compare well with available data.

A suite of snow and ice penetrating radar arrays, used for polar remote sensing, have been developed by a team of University of Kansas and DARcorporation engineers in support of the NASA Operation Ice-Bridge program. This collaborative industry/academic partnership provided design, analysis, fabrication and testing of antenna fairings for the above mentioned radar array, as well as subsequent installation and flight testing on a Lockheed P-3 Orion aircraft. This installation has since flown multiple successful missions, generating in excess of 150TB of snow and ice data. This paper discusses the effect of the antennas on the aerodynamics, and performance, as well as the structure and manufacturing of the pylons and the antenna fairings.

Weight investigation is carried out on a novel airplane wing layout configuration where the two wings are split and staggered along the fuselage. This special layout excludes the need of horizontal tails by using the aft wing control surfaces for pitch control. Finite element analyses are carried out to investigate stress, deformation and buckling characteristics. As a comparison, a baseline finite element model is built with conventional wing layout beside the split-wing finite element model. Key failure modes are identified and causes are investigated. Besides finite element analysis, analytical methods are also explored to enable parametric trade studies.

Snow and ice penetrating radar antenna arrays have been developed and flown on NASA DC-8 and P-3 aircraft as part of the NASA Operation Ice-Bridge program. These arrays required custom, externally-mounted fairings to house the antennas. This paper documents the method for generating project requirements, load development, and subsequent structural design and analysis. Static load and modal tests were also performed to verify the physics based simulations. Involvement in such interdisciplinary work provides the basis for large numbers of graduate and undergraduate students to gain practical experience in designing, fabricating, ground testing and flight testing aerospace structures.

Fuel cell technology based on natural gas is a kind of promising and cleaning energy conversion technology under development. The generation mechanism of fuel cell is different from the traditional power generation device, and the efficiency of fuel cell is not restricted to Carnot cycle, therefore, it has almost the highest efficiency in most of the power generation device. Fuel cell as the motor of building cogeneration system is the integration of high efficiency energy conversion type with high efficiency energy utilization method. In this paper, a Solid oxide fuel cell (SOFC)-based Building Combined Cooling, Heating and Power (BCHP) system is simulated, and it can meet the basically electrical and heating (cooling) load of the end users. The peak power load could be supplied by power grid, and the peak heating (cooling) load could be supplied by the backup equipments. In this paper, the restricted nonlinear optimization model is built in order to solve the economic load balancing problem of the system, and the sequential quadratic programming (SQP) is used to successfully solve the optimal equipment capacity for the production costs minimization on the equality constraint of customer’s heat and power requirement, and the other inequality constraint of equipment capacity. The computation results show that it is a good method to size SOFC power generation capacity meet the electrical base load of a building. The model can be used to provide guidance in the SOFC based BCHP system design and optimization.Copyright © 2009 by ASME

This paper describes the preliminary design, structural layout, detailed sizing and manufacturing of an uninhabited air vehicle (UAV) that will primarily be used to measure changes in glacial conditions in Antarctica and Greenland. This includes a brief description of the requirements definition and preliminary configuration design. Preliminary component weight estimations are created using empirical formulas then compared to the results of structural sizing using finite element analyses. The goal of this effort is to design an aircraft capable of autonomous operation in extreme climates that can carry various sensors including radar depth sounders and magnetometers.

Constrained layer damping (CLD) treatments, wherein a viscoelastic sheet is sandwiched between a structural sheet or plate and a covering or constraining sheet, are widely used to suppress vibration and noise. Techniques for predicting the damping loss factor for such a construction include the Ross-Ungar-Kerwin (RUK) complex modulus technique [1] (which is only applicable when the treatment completely covers the structural sheet), the Modal Strain Energy Method [2] and the Analytical Power Input Method [3].

Damping loss factors are evaluated for honeycomb composite beams with differ ent configurations of particle damping . Damping effectiveness is evaluated in two ways. First, measured frequency response functions are used in a conventional, polynomial curve -fitting modal method to evaluate damping loss factors at several natural res onanc es in the low frequency range. Secondly, the power input method is applied to evaluate damping loss factors over a broad frequency range. Both damping estimation methods (modal method and power input method) yield consistent loss factor estimations. The effect of different damping configurations has been studied, showing substantial differences in loss factor. Most interestingly, loss factors as high as 0.1 9 have been measured, corroborating reports by others. Further, a simplified fluid model of t he partially -filled honeycomb cell has been found to predict the frequency band of peak damping . This technology then, shows the potential for designing high levels of damping in distinct frequency bands, which is of interest for aircraft interior noise su ppression.

In this paper, we propose a piecewise smooth SI pest control system to model the process of spraying pesticides and releasing infectious pests. We assume that the pest population consists of susceptible pests and infectious pests, and that the disease spreads horizontally between pests. We take the susceptible pest as the control index on whether to implement chemical control and biological control strategies. Based on the theory of Filippov system, the sliding-mode domain and conditions for the existence of real equilibria, virtual equilibria, pseudo-equilibrium and boundary equilibria are given. Further, we show the global stability of real equilibria (or boundary equilibria) and pseudo-equilibrium. Our results can provide theoretical guidance for the problem of pest control.