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Ischemic brain injury is a disease with high incidence rate, high disability rate and high mortality rate. The insufficiency of cerebral blood supply makes cerebral ischemia and hypoxia, leading to severe oxidative stress, severe inflammatory reaction and ultimately irreversible brain tissue damage or apoptosis.Metformin(Met,Abdominal inject,20 mg/kg,28days)is a guanidine derivative extracted from goats and is the first choice for first-line treatment of type 2 diabetes.In this study, the rat model of middle cerebral artery occlusion(MCAO) reperfusion injury and the hippocampal HT22 cell oxygen glucose privatization / reoxygenation (OGD/R) cell model were used to observe the effects of Met on the morphology of hippocampus, Nrf2, apoptosis factors, oxidative stress factors and inflammatory factors after CI/RI in rats ,it was further revealed that Met by using LY294002 antagonist, a specific kinase (phosphoinositide-3 kinase,PI3K) phosphoinositol-3 kinase, regulates the PI3K/Akt/Nrf2 signaling pathway in role in CI/RI.

Exploring a strategy to effectively repair cerebral ischemic injury is a critical requirement for neuroregeneration. Herein, we transplanted a neural stem cell (NSC)-laden self-healing and injectable hydrogel into the brains of ischemic rats and evaluated its therapeutic effects. We observed an improvement in neurological functions in rats transplanted with the NSC-laden hydrogel. This strategy is sufficiently efficient to support neuroregeneration evidenced by NSC proliferation, differentiation, and athletic movement recovery of rats. This therapeutic effect relates to the inhibition of the astrocyte reaction and the increased expression of vascular endothelial growth factor. This work provides a novel approach to repair cerebral ischemic injury.

Metformin (Met) is a commonly used drug in the treatment of type 2 diabetes. Currently, it has been found that Met can effectively reduce the incidence of stroke and exert anti‐inflammatory effects. However, its role in ischemia‐reperfusion (I/R)‐induced nerve injury remains unclear. This study aims to investigate the neuroprotective effects of Met in I/R‐induced neuron injury as well as the underlying mechanism. A middle cerebral artery occlusion (MCAO) model was established in Sprague Dawley (SD) rats, which were then treated with different doses of Met. Neurological deficits of rats were measured at different times post‐surgery. TTC staining was done to observe the volume of cerebral infarction. HE staining was performed to observe pathological changes of brain tissues. Immunohistochemistry was performed to observe the expression of inflammatory factors in the cerebral tissues. qRT‐PCR method was used to detect the relative expression of PI3K, Akt mRNA in cells after 24 h of drug action. Western blot method was used to detect the expression of PI3K, p‐PI3K, Akt, and p‐Akt in hippocampus. What is more, in vitro experiments were performed on BV2 microglia to verify the role of Met against oxygen‐glucose deprivation (OGD). As a result, Met dose‐dependently attenuated neurological deficits and neuronal apoptosis. Besides, Met administration also significantly reduced BV2 cells apoptosis and inflammatory response. Mechanistically, Met inactivated PI3K/Akt pathway induced by I/R and OGD, while it upregulated PI3K. In conclusion, Met protected rats from cerebral I/R injury via reducing neuronal apoptosis and microglial inflammation through PI3K/Akt pathway., This study investigated the new use of metformin (Met), a conventional treatment for type 2 diabetes mellitus, and the neuroprotective effect of Met on cerebral ischemia‐reperfusion injury of brain by inhibiting inflammation, oxidative stress, apoptosis, etc. It belongs to old medicine and new use and has important research value.

Midazolam, a widely used anesthetic, inhibits proliferation of neural stem cells (NSCs) and induces neuroapoptosis in neonates. Dexmedetomidine, an effective auxiliary medicine in clinical anesthesia, protects the developing brain against volatile anesthetic-induced neuroapoptosis. Whether dexmedetomidine protects against neurogenesis damage induced by midazolam remains unknown. This study aims to clarify the protective effect of dexmedetomidine on midazolam-induced neurogenesis damage and explore its potential mechanism. Postnatal 7-day-old Sprague-Dawley (SD) rats and cultured NSCs were treated with either normal saline, midazolam, or dexmedetomidine combined with midazolam. The rats were sacrificed at 1, 3, and 7 days after treatment. Cell proliferation was assessed by 5-bromodeoxyurdine (BrdU) incorporation. Cell viability was determined using MTT assay. Cell differentiation and apoptosis were detected by immunofluorescent staining and terminal dUTP nick-end labeling (TUNEL), respectively. The protein levels of p-JNK, p-P38, and cleaved caspase-3 were quantified using Western blotting. Midazolam decreased cell proliferation and increased cell apoptosis in the subventricular zone (SVZ), the subgranular zone (SGZ) of the hippocampus, and cultured NSCs. Moreover, midazolam decreased cell viability and increased the expression of p-JNK and p-P38 in cultured NSCs. Co-treatment with dexmedetomidine attenuated midazolam-induced changes in cell proliferation, viability, apoptosis, and protein expression of p-JNK and p-P38 in cultured NSCs. Midazolam and dexmedetomidine did not affect the differentiation of the cultured NSCs. These results indicate that dexmedetomidine alleviated midazolam-induced neurogenesis damage via JNK and P38 MAPK pathways.

In an electric power system with a high penetration of wind power, wind power ramps events (WPREs) has been an important factor of wind power integration and development. To predict them accurately and adopt a timely response, it is important to understand their characteristics. Wind power ramps are affected by various factors and in a complicated way that differ in different wind farms. To give insight into wind power ramps and their dependencies, an impact factors model of wind power ramps has been developed based on orthogonal test theory. By classifying the possible impact factors of wind power ramps into several grade levels and comparing the difference of orthogonal test results brought by each factor, the model enables: compare the effect strength of factors quantitatively; and determine the dominant factors, as well as grade level combinations of these factors with the highest risk of wind power ramps. A wind farm from China is used to illustrate the analysis and verify its feasibility. The main advantage of this model is shown to be: (1) The model can be generalized to any wind farm to explore the factors affecting the wind power ramps; (2) Not only the impact of factors themselves but also the interaction among the factors can be assessed; (3) Any parameter of wind power ramps could be analyzed as experimental index, realizing the analysis of wind power ramps from various aspects.

In the era of rapid development of the Internet, network media has become a new window for people to understand the outside world due to its fast speed and wide spread. News is a channel for people to know about Surrounding Information, but thousands of news are produced every day on the Internet. These news are needed or not in inside. How to efficiently and accurately obtain the news content we need from the website is a great need in people’s life. This system aims to collect news on specific websites and return it to users with concise and clear pages. Users can search specific keywords to select news that they are interested in so as to realize personalization for users. This system crawls and processes the domestic financial news content, which is convenient for people to process the information. In order to avoid duplication of information, the system has also implemented a self-defined deduplication rule. In the specific implementation, the system is written using Python in conjunction with the Scrapy framework and Django framework, which can simplify the system code to a certain extent. The practical value of this system lies in the timely, efficient and convenient access to domestic financial news that people care about, need and are interested in.

Piezoelectric transducers have been widely employed in the field of structural health monitoring (SHM). Currently, most piezoelectric transducers based non-destructive monitoring method lays basis on wave-based method. The change of wave after propagating in the target medium can reflect the internal state of the structure, such as damage and porosity. Owing to that concrete is a severely heterogeneous material at micro scale, the relationship between stress wave parameters and microstructure of concrete such as pores and preexisting cracks in concrete is still unclear, which limits the generalization of monitoring system in different concrete structures. This paper presents an experimental study by setting up a kind of monitoring platform with piezoelectric transducers to investigate the relationship between porosity in cement paste and stress wave parameters. Meanwhile, 3D models of cement paste specimens were built with X-ray computed tomography (CT) scanning method, and the actual pore structure and distribution inside the specimens were obtained. The test and numerical results share similar decreasing trend of amplitude and velocity with an increment of porosity. It indicates that the proposed 3D model building method provides a vivid way to investigate the influence of micro-structure on stress wave transferring in cement based materials. Additionally, it also provides a promising approach to assess the porosity in cementitious materials using smart aggregate (SA)-based non-destructive monitoring method.

At present, DC supply technology has become a research hotspot again. And the wide application of all-controlling power electronics devices also makes DC distribution system usher in a new opportunity for development. Through the analysis of the possible power quality problems existing in DC power distribution network, a set of comprehensive evaluating method for DC power quality is proposed in this paper. To avoid the excessive subjectivity or objectivity of weight coefficients, the combination weighting method based on maximizing deviation is adopted to allocate the subjective and objective weight proportion fairly, thus making the decision of comprehensive weights more accurate. Fuzzy matter-element model is built to evaluate power quality of DC distribution network in order to solve the problems in DC power quality evaluation process, such as fuzziness and uncertainty. Finally, numerical examples show that the proposed comprehensive evaluation model can be used to evaluate DC power quality with feasible and practicability results.

With the advantages of low loss, low cost, high efficiency and high reliability, DC distribution network has become the new trend of the future grid development. There are some power quality problems distinct from AC system in DC distribution network. Through modeling and simulations, the impact on bus voltage power quality of LVDC distribution network is studied under different faults occurred in DC and AC side. Research suggests that faults in DC and AC side will cause voltage fluctuations, voltage sags and harmonics of DC bus, and the difference of the impact on DC bus power quality is obvious with different fault locations, fault impedance and fault types.

Background: A rat model for neonatal hypoxic-ischemic brain damage (HIBD) was established to observe the effect of ischemic postconditioning (IPostC) on cerebral edema and the AQP4 expression following HIBD and to verify the neuroprotection of IPostC and the relationship between changes of AQP4 expression and cerebral edema. Methods: Water content was measured with drywet method, and AQP4 transcription and the protein expression of the lesions were detected with real-time PCR and immunohistochemistry staining, respectively. Results: Within 6-48 hours, the degree of ipsilateral cerebral edema was significantly lower in IPostC-15 s/15 s group than in HIBD group. Similar to the HIBD group, the AQP4 transcription and expression in the IPostC group showed a downward and then upward trend. But the expression was still more evident in the HIBD group than in the IPostC-15 s/15 s group. From 24 to 48 hours, IPostC-15 s/15 s decreased the slowing down expression of AQP4 . Conclusion: IPostC has neuroprotective effect on neonatal rats with HIBD and it may relieve cerebral edema by regulating the expression of AQP4.

The retinal ischemia-reperfusion injury (RIR) is a common pathological process that leads to progressive visual loss and blindness in many retinal diseases such as retinal vascular occlusion disease, diabetic retinopathy, and acute glaucoma. Currently, there has been no effective therapy. The purpose of this study was to investigate the effects of transplantation of retinal progenitor cells (RPCs) into the subretinal space (SRS) and the superior colliculus (SC) in a rat model of RIR injury. We used cultured postnatal day 1 rat RPCs transfected with adeno-associated virus containing the cDNA encoding enhanced green fluorescence protein (EGFP) for transplantation. RIR injury was induced by increases in the intraocular pressure to 110 mmHg for 60 min. The effects of transplantation were evaluated by immunohistochemistry, electroretinography (ERG), and visual evoked potentials (VEP). We found that in rats with RIR injury, RPCs transplanted into the SRS and the SC survived for at least 8 weeks, migrated into surrounding tissues, and improved the ERG and VEP responses. Cells transplanted into the SC improved the VEP response more than those transplanted into the SRS. Our data suggest that transplantation of RPCs into the SRS and the SC may be a possible method for cell replacement therapy for retinal diseases.

Combined with the flying speed, altitude and comfort features of fixed-wing propeller aircraft, and the vertical taking off and landing characteristics of rotorcraft, the tiltrotor aircraft has unique advantages. As a result, many researchers, represented by U.S. aviation industry, are involved in the research and development of tiltrotor aircraft, and think that it has comprehensive application prospects in the military and civil domains. However, dispute has never stopped in the past years along with the development of tiltrotor aircraft. Although it has splendid advantages and good prospects in the future, there are also many inherent deficiencies at present. Including but not limited to the following areas: lower hover performance contrasted to helicopter, reduced forward flight performance against to propeller aircraft, defective reliability and maintainability, burdensome cost, and issues about airworthiness and safety. Mainly from the airworthiness point of view, the impact to the development of tiltrotor aircraft is analyzed in this paper. Based on the analysis above, the evolution trend of tiltrotor aircraft in the next period of time is discussed, so as to provide reference for the related research in aviation industry.

There is no explicit definition for critical ice shapes, and it is only mentioned in some ACs. Here, a rational and applicable definition for critical ice shapes is given based on well understanding of present literatures. Then, the available icing certification guidance concerning the various “critical ice shapes” is outlined. Different methods for determination of ice shapes as well as procedures are presented, and their characteristics are compared and analyzed. Based on the Combination Airfoil Assumption first presented by Glahn et al and developed by Farooq Saeed, we suggest a simple and useful method to determine the critical ice shapes on a normal airfoil which can be called combination airfoil comparison method. This method can be used to quickly get a preliminary ice shape for icing certification, but its criticality should be verified by other means of determining critical ice shapes. In order to examine the availability of this method, examples of Airbus aircraft types that have passed icing certification will be given. We hope that our findings and recommendations will be helpful to the applicant and icing certification team during aircraft icing certification.

Particle Swarm Optimization (PSO) algorithm is easy to fall into premature local convergence. In this paper, inheriting the crossover particle swarm optimization combined with the crossover operator, we proposed Crossover Particle Swarm Optimization with Incremental Learning (ILCPSO). ILCPSO builds two levels to overcome the local convergence and obtain the optimal solution. Firstly we introduce cross-operation into PSO, which exchanges good “genes” of particles in population according to certain crossover probability. It takes full advantage of information of the particle swarm to get the global optimal solution. Followed by the introduction of incremental learning, we add two sets of particles in prior to choose their own “first teacher”, then according to the diversity of the population use two different learning methods to update their knowledge again. After competition with the respective “first teacher” the fittest will be survival, in order to ensure that the population size will not expand. Final validation as opposed to the crossover particle swarm optimization algorithm, the complexity of the algorithm has not increased significantly when the performance is greatly improved.

Ionospheric delay is one of the major error sources in GNSS navigation and positioning. Nowadays, the dual-frequency technique is the most widely used in ionospheric refraction correction. However, dual-frequency measurements can only eliminate the first-order term of ionospheric delay, while the effect of the second-order term on GNSS observations may be several centimeters. In this paper, two models, the International Reference Ionosphere (IRI) 2007 and International Geomagnetic Reference Field (IGRF) 11 are used to estimate the second-order term through the integral calculation method. Besides, the simplified single layer ionosphere model in a dipole moment approximation for the earth magnetic field is used. Since the traditional integral calculation method requires large calculation load and takes much time, it is not convenient for practical use. Additionally, although the simplified single layer ionosphere model is simple to implement, it results in larger errors. In this study, second-order term ionospheric correction formula proposed by Hoque (2007) is improved for estimating the second-order term at a global scale. Thus, it is more practicable to estimate the second-order term. More importantly, its results have a higher precision of the sub-millimeter level for a global scale in normal conditions. Compared with Hoque’s original regional correction model, which calculates coefficients through polynomial fitting of elevation and latitudes, this study proposes a piece-wise look-up table and interpolation technique to modify Hoque model. Through utilizing a table file, the modified Hoque model can be conveniently implemented in an engineering software package, like as PANDA in this study. Through applying the proposed scheme for the second-order ionospheric correction into GNSS precise positioning in both PPP daily and epoch solutions, the results have shown south-shift characteristics in daily solution at a global scale and periodic change with VTEC daily variation in epoch positioning solution.

An Oilfield Completion depth error calculation method based on DTW is put forward in this paper. According to the position of oil reservoir is not change in the stratum, and two Natural Gamma Curves which are from Open Hole Logging and Cased Hole Logging, are similar to each other, Activity Analysis is used to recognize the oil layer interface, DTW algorithm is used to compare the similarity between two natural gamma curves. Finally, by moving the Natural Gamma Curves got from Cased Hole Logging, to get the best matches position where the bending path is minimum in all of the best bending path, we could calculate the precise Depth Error Value.

FAA has issued a Notice of Proposed Rulemaking (NPRM) on supercooled large drops (SLD) icing conditions[1]. Based on following up and studying of the newest SLD icing materials, the paper gives a detailed analysis of SLD icing conditions for transport category airplanes airworthiness problems. The proposed Part 25, Appendix O about SLD icing conditions are analyzed and compared with Part 25, Appendix C, including icing clouds extend or range, altitude-temperature envelop, liquid water content (LWC) and drop diameter distribution. The changes of icing envelopes used by IPS design and certification are detailed analyzed. The proposed SLD amendment related regulations are summarized, and the proposed new §25.1420 are deeply analyzed, including the requirements of each subsection, and the requirements of the three SLD icing certification options. Moreover, the certification and compliance of the proposed §25.1420(a) directly referring to the three certification options are discussed, respectively.

Background Sesame is an important oil crop, but limited transcriptomic and genomic data are currently available. This information is essential to clarify the fatty acid and lignan biosynthesis molecular mechanism. In addition, a shortage of sesame molecular markers limits the efficiency and accuracy of genetic breeding. High-throughput transcriptomic sequencing is essential to generate a large transcriptome sequence dataset for gene discovery and molecular marker development. Results Sesame transcriptomes from five tissues were sequenced using Illumina paired-end sequencing technology. The cleaned raw reads were assembled into a total of 86,222 unigenes with an average length of 629 bp. Of the unigenes, 46,584 (54.03%) had significant similarity with proteins in the NCBI nonredundant protein database and Swiss-Prot database (E-value < 10-5). Of these annotated unigenes, 10,805 and 27,588 unigenes were assigned to gene ontology categories and clusters of orthologous groups, respectively. In total, 22,003 (25.52%) unigenes were mapped onto 119 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway database (KEGG). Furthermore, 44,750 unigenes showed homology to 15,460 Arabidopsis genes based on BLASTx analysis against The Arabidopsis Information Resource (TAIR, Version 10) and revealed relatively high gene coverage. In total, 7,702 unigenes were converted into SSR markers (EST-SSR). Dinucleotide SSRs were the dominant repeat motif (67.07%, 5,166), followed by trinucleotide (24.89%, 1,917), tetranucleotide (4.31%, 332), hexanucleotide (2.62%, 202), and pentanucleotide (1.10%, 85) SSRs. AG/CT (46.29%) was the dominant repeat motif, followed by AC/GT (16.07%), AT/AT (10.53%), AAG/CTT (6.23%), and AGG/CCT (3.39%). Fifty EST-SSRs were randomly selected to validate amplification and to determine the degree of polymorphism in the genomic DNA pools. Forty primer pairs successfully amplified DNA fragments and detected significant amounts of polymorphism among 24 sesame accessions. Conclusions This study demonstrates that Illumina paired-end sequencing is a fast and cost-effective approach to gene discovery and molecular marker development in non-model organisms. Our results provide a comprehensive sequence resource for sesame research.