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The detection for internal defects of the practical aviation carbon fiber reinforced polymer (CFRP) using different modes of laser was discussed in this paper. The results show that the effect of the laser with long pulsed wave heating mode is the best, and then sawtooth wave mode is followed by sine wave mode. Besides, the valid image processing method plays a significant role in improving the effect of differential laser infrared thermography. Compared with the detection results of thermal lamp thermography, the effect of differential laser thermography is better. There are two main advantages of using a planar laser to heat the aviation carbon fiber composites: (1) the detection speed is so fast, which only takes a few seconds to complete the whole detection process; (2) laser method is more flexible than thermal lamp thermography because of the range detected can be adjusted according to the aim of experiments.

Delirium is the most common postoperative complication in older patients after prolonged anesthesia and surgery and is associated with accelerated cognitive decline and dementia. The neuronal pathogenesis of postoperative delirium is largely unknown. The unfolded protein response (UPR) is an adaptive reaction of cells to perturbations in endoplasmic reticulum function. Dysregulation of UPR has been implicated in a variety of diseases including Alzheimer's disease and related dementias. However, whether UPR plays a role in anesthesia-induced cognitive impairment remains unexplored. By performing in vivo calcium imaging in the mouse frontal cortex, we showed that exposure of aged mice to the inhalational anesthetic sevoflurane for 2 hours resulted in a marked elevation of neuronal activity during recovery, which lasted for at least 24 hours after the end of exposure. Concomitantly, sevoflurane anesthesia caused a prolonged increase in phosphorylation of PERK and eIF2α, the markers of UPR activation. Genetic deletion or pharmacological inhibition of PERK prevented neuronal hyperactivity and memory impairment induced by sevoflurane. Moreover, we showed that PERK suppression also reversed various molecular and synaptic changes induced by sevoflurane anesthesia, including alterations of synaptic NMDA receptors, tau protein phosphorylation, and dendritic spine loss. Together, these findings suggest that sevoflurane anesthesia causes abnormal UPR in the aged brain, which contributes to neuronal hyperactivity, synapse loss and cognitive decline in aged mice.

Curvature of wavefront is very large near source point. However, plane wavefront assumption is adopted when calculating traveltimes by use of finite-difference scheme. Therefore, source singularity problem exists for all finite-difference based eikonal solvers. Traveltime error caused by the source singularity can spread from source to the whole computational domain, and make traveltimes inaccurate. The factored eikonal equation can deal with source singularity very well. The fast sweeping method (FSM) is chosen to solve the factored eikonal equation in this article (factored FSM). In principle, it decomposes solution of general eikonal equation into product of two factors. The first factor can be calculated analytically or numerically, while the second factor is the underlying function. Eikonal solver plays a significant role in velocity inversion. An accurate and efficient eikonal solver can improve the effect of tomogram. The factored FSM is adopted in the following velocity inversion. Three evaluation criteria are defined to test accuracy and convergence of velocity inversion. The first method is the root-mean-square (RMS) of traveltime residuals. The second method is the percentage perturbation of inverted agaist initial velocity model. The third method is the percentage ratio of inverted against real velocity model. When inversion incorporating with the factored FSM, numerical examples show that: (1) RMS of traveltime residuals can converge to a smaller level, (2) percentage perturbation of inverted against initial velocity model is also smaller, (3) percentage ratio of inverted against real velocity model can reach up to a greater value.

Perioperative neurocognitive disorder may develop in vulnerable patients following major operation. While neuroinflammation is linked to the cognitive effects of surgery, how surgery and immune signaling modulate neuronal circuits, leading to learning and memory impairment remains unknown. Using in vivo two-photon microscopy, Ca

The structure and fractal characteristics of nanopores of high-rank coal were investigated using an approach that integrates N2 adsorption and field emission scanning electron microscopy (FE-SEM). The results indicated that the high-rank coal of the Shanxi Formation has a complex pore-fracture network composed of organic matter pores, mineral-related pores, and microfractures. The pore type of high-rank coal tends to be complicated, and the main pore types are inkbottle pores and open pores, which are more conducive to methane enrichment. The Ro,max has a negative relationship with the total pore volume. In addition, the ash and inertinite contents show a positive correlation with the average pore size (APS), while the fixed carbon content exhibits a negative relationship with the APS. The pore structure of high-rank coal is controlled not only by the degree of metamorphism but also by coal composition, which leads to the variation in pore structure becoming more complicated. With the increase in coal metamorphism, high-rank coal with high amounts of fixed carbon content generally possesses a higher irregularity in pore structure. No obvious relationship was observed between D2 and the coal components, which indicates that the pore structure, ash content, moisture content and other factors controlled by the metamorphism of coal have different effects on D2 that lead to this inapparent relationship. A negative relationship exists between adsorption volume and D1, which indicates that the high irregularity of the pore structure is not conducive to methane absorption and that no obvious correlation exists between the adsorption volume and D2. In the high-rank coal, the high D1 value represents the complexity and heterogeneity of the pore structure and represents a low adsorption affinity for methane molecules; in addition, D2 has no effect on the methane adsorption capacity.

Due to the unique adsorption and desorption characteristics of coal, coal reservoir permeability changes dynamically during coalbed methane (CBM) development. Coal reservoirs can be classified using a permeability dynamic characterization in different production stages. In the single-phase water flow stage, four demarcating pressures are defined based on the damage from the effective stress on reservoir permeability. Coal reservoirs are classified into vulnerable, alleviative, and invulnerable reservoirs. In the gas desorption stage, two demarcating pressures are used to quantitatively characterize the recovery properties of permeability based on the recovery effect of the matrix shrinkage on permeability, namely the rebound pressure (the pressure corresponding to the lowest permeability) and recovery pressure (the pressure when permeability returns to initial permeability). Coal reservoirs are further classified into recoverable and unrecoverable reservoirs. The physical properties and influencing factors of these demarcating pressures are analyzed. Twenty-six wells from the Shizhuangnan Block in the southern Qinshui Basin of China were examined as a case study, showing that there is a significant correspondence between coal reservoir types and CBM well gas production. This study is helpful for identifying geological conditions of coal reservoirs as well as the productivity potential of CBM wells.

This study was to investigate the spectral characteristics of aeronautical composite matrix resins (ACMRs) that differ in dielectric properties in terahertz frequency range. Terahertz time-domain spectroscopy was employed to examine the spectral absorption and dielectric dispersion characteristics of five ACMRs of three major types, namely, epoxy resins 3238A and BA9916, cyanate ester (CE) resin 9915, and bismaleimide (BMI) resins QY8911 and QY9611, between 0.2 THz to 1.6 THz. The refractive index n , the absorption coefficient α and the real part e ′ and imaginary part e ″ of the dielectric constant of each resin were calculated. On this basis, the relaxation process of dipoles was theoretically analyzed using the Debye model. The results showed that, e ″ of each epoxy resin was higher than that of each BMI resin, while e ″ of the CE resin was the lowest. The CE resins had the lowest e ′ and exhibited the highest and most stable dielectric performance, followed by the BMI resins, whereas the epoxy resins exhibited fluctuating and slightly less stable dielectric performance. This study gives, for the first time, the basic parameters of five ACMRs (epoxy, CE and BMI resins) in terahertz frequency range, and provides an important reference for THz nondestructive testing of aeronautical composites.

With the development of infrared technology, the cost of detector is decreasing and the application of staring imaging is becoming more and more extensive, which promotes the improvement of the antimissile warning level of the weapon platform. In the paper, a method for the antitank missile warning and precise recognition is presented based on the infrared characteristics of missile exhaust plume and the motion features of ballistic target. Firstly, the current status of missle warning technology is summarized. A hemispherical infrared staring detector of actual application is designed for ground weapon platform. The key technical indicators are given, and the technical routine of point target imaging warning is illustrated. Based on the above warning devices and typical observation scenarios, the relationship between target infrared radiation, observation distance and motion velocity is established, and a detection warning model is established. Combining with the actual application scene, the infrared warning distance window optimization, velocity calculation precision and point target recognition threshold are synthetically verified, and the analysis and quantification of critical data are gived. It showes that in typical scene detection and warning, the modeling of infrared characteristics and motion features can effectively achieve the antitank missile warning; under the control of observation conditions, the uncertainty of infrared radiation and motion velocity are less than 10%, which can be used to precise recognition the target under threshold of 30%.

In this paper, the feasibility of differential spread laser infrared thermography (DSLIT) to detect delamination and impact damage in carbon fiber reinforced polymer (CFRP) is investigated. The proposed method can significantly eliminate the influence of the uneven laser energy distribution and improve the detectability of laser infrared thermography. First, numerical simulation is carried out following the procedure of DSLIT to verify the feasibility of this method. Secondly, through experiments on the detection of defects both in practical aviation CFRP and common CFRP, the feasibility of DSLIT is confirmed. For the common CFRP, this technique has excellent performance: a defect at a depth of 2.5 mm was detected successfully, with the width-to-depth ratio reaches to 2.4. Comparatively speaking, the defect detection results for the aviation CFRP are not as good as those for the common CFRP. However, defects at a depth of 1.125 mm were detected, with the width-to-depth ratio reaching 2.67. In addition, defects caused by a low-velocity impact in practical aviation CFRP were successfully detected. Finally, the thermal data were processed by image processing methods such as sequence differential preprocessing (SDP), phase analysis (PA) and principal component analysis (PCA) to enhance the defect imaging results.

Composite structures have played a significant role in enhancing airplane’s performance However, defects inside can be a potential threat to flight safety. To resolve the hazard. FMECA was applied to the defect analysis of composite structures on airplane’s wing. And the failure mode of the highest criticality was found to be the impact damage. Then impact test on typical composite laminates was carried out. The caused damage was qualitatively analysed and proved impact of low energy brings latent risk. Practical solution was put forward to improve the safety or reliability of the applied composites in the airplane.

The imaging tracking systems often face different backgrounds,such as the ground, the sky, the sea, the jungle, the Gobi, tec. This paper is based on the complexity of different backgrounds and the mechanism and method of automatic optimization of the tracking algorithm under different background conditions. The paper presents a comprehensive decision model of background complexity, which combines the statistical characteristics of gray scale, image texture features, edge characteristics and high frequency features of the image. The model can realize the scientific and effective combination of multi algorithm fusion and tracking algorithm of autonomous scheduling. It can improve the adaptive and autonomous decision-making tracking ability when the diversity tasks are carried out.

To provide a more effective auxiliary tool for maintenance and inspection in small space, a miniature camera optical system is designed. According to the real work situation, a small camera structure with 25 mm long and 16 mm of the focal length has been formed in this paper. At the same time, Zemax software is utilized to analyze the image quality of the camera lens. The results show that the field curvature is less than 0.1 in optical band and the maximum distortion is less than 0.5%.The RMS and GEO of the image formed under the selection of height condition is small. Under the condition of different temperature and pressure, the image quality can be ensured and the MTF of this system is greater than 0.35 which meets the design requirements. This structure can be a reference structure for the optical part of a maintenance support system.

The radome composing of GFRP with sandwich structure is easy to generate impact damage, core material shedding and fiber delamination during the service causing the structural strength and the performance of the waves to fall. Then it affects the normal operation of the radar antenna system. The characteristics of terahertz wave contain the low photon energy, the strong penetrating ability of dielectric material, the transient, broadband and coherence. The simulation experiment of reflective NDT (nondestructive testing) of overlapped multi-delamination defects in the skin of the radome was realized by terahertz wave in CST STUDIO SUITE software simulation platform. The energy, reflection and transmission coefficient of THz wave were analyzed in time domain and frequency domain, and a relatively ideal result had been obtained by using the principle of THz-TDS technology. The paper verified a favorable effect of the related technology of THz at NDT and the exploration of material characteristics on composites with sandwich structure.

Flos Chrysanthemi Indici (FCI) is a Chinese herbal medicine used in China for over 2000 years. In this study, its ethanol extract (EFCL) was found to protect against hydroxyl radical ( OH) induced oxidative damages to mesenchymal stem cells (MSCs) and DNA. To explore the mechanism, EFCL was further determined by chemical and antioxidant assays. Folin–Ciocalteu colorimetric assay suggested that content of total phenolics was 93.85 ± 3.56 mg catechin/g and HPLC analysis indicated a content of 10.05 ± 1.44 mg/g as chlorogenic acid in EFCI. Antioxidant assays revealed that EFCI could also scavenge O 2 − radical (IC 50 58.74 ± 1.30 μg/mL), DPPH radical (IC 50 46.46 ± 1.35 μg/mL) and ABTS + radical (IC 50 20.59 ± 0.52 μg/mL), bind Fe 2+ (IC 50 364.27 ± 19.57 μg/mL) and Cu 2+ (IC 50 734.77 ± 34.69 μg/mL), reduce Fe 3+ (IC 50 147.11 ± 11.09 μg/mL) and Cu 2+ (IC 50 35.69 ± 3.14 μg/mL). On the basis of mechanistic analysis, we concluded that FCI can effectively protect against hydroxyl-induced damages to DNA and MSCs, therefore FCI shows promise as a possible therapeutic reagent for many diseases. The effect may be mainly attributed to phenolics especially chlorogenic acid, which exerts the antioxidant action possibly through metal-chelating, and radical-scavenging which is via hydrogen atom transfer (HAT) and/or sequential electron proton transfer (SEPT) mechanisms.

The mitogen-activated protein kinase (MAPK) pathway is aberrantly activated in many human cancers, including breast cancer. Activation of MAPK signaling is associated with the increased expression of a wide range of genes that promote cell survival, proliferation, and migration. This report investigated the influence of MAPK signaling on the regulation and expression of JUNB in human breast cancer cell lines. JUNB has been associated with tumor suppressor and oncogenic functions, with most reports describing JUNB as an oncogene in breast cancer. Our results indicated that JUNB expression is elevated in MCF10A(met), SKBR3, and MDA-MB-231 human breast cancer cell lines compared to nontransformed MCF10A mammary epithelial cells. Increased RAS/MAPK signaling in MCF10A(met) cells correlates with the increased association of RNA polymerase II (Pol II) phosphorylated on serine 5 (Pol IIser5p) with the JUNB proximal promoter. Pol IIser5p is the "transcription initiating" form of Pol II. Treatment with U0126, a MAPK pathway inhibitor, reduces Pol IIser5p association with the JUNB proximal promoter and reduces JUNB expression. Oncostatin M (OSM) enhances MAPK and STAT3 signaling and significantly induces JUNB expression. U0126 treatment reduces OSM-induced Pol IIser5p binding to the JUNB proximal promoter and JUNB expression, but does not reduce pSTAT3 levels or the association of pSTAT3 with the JUNB proximal promoter. These results demonstrate that the MAPK pathway plays a primary role in the control of JUNB gene expression by promoting the association of Pol IIser5p with the JUNB proximal promoter.

The use of infrared sensors to detect and obtain the real image of the moving target is an important means for the test of weapon equipment and the monitoring of space launch. To better play the advantages of infrared devices visibility at day and night, the role of distance, solved the details of the image display effect by eye gray resolution constraints problem for ground multisensor surveillance system field situation awareness requirements, proposed color visible image and infrared image registration and image processing based on color transfer and contrast equalization enhancement method. First, analyzed the implementation of dynamic monitoring system based on ground live monitoring system, through the acquisition of color image and infrared image, and multi frame color images combining to construct the scene, established the acquisition, processing, application process of the visible-infrared image registration; Then, analyzed the representation of color transfer process of color space and the features of real-time processing, will color scene graph expressed as geometry, color space, comprehensive expression of brightness distribution, According to the correspondence between the infrared image and the color scene image, obtained the color space representation of the infrared image; Next, Improved the infrared image gray distribution by contrast equalization method, by contrast limited adaptive histogram equalization to improve the display effect of gray details. As for the validation of the proposed method, using the method in the paper to enhance the infrared image, the experimental results show that the integrated color transfer and contrast balance, improved the visual effect of image display and showed more details information, Presented more detailed information, improved the image display effect.

A new rhodamine B derivative bearing a hydrazone group has been designed and prepared. The synthesized colorimetric and fluorescent molecular chemosensor can be used as a dual probe, selectively detecting Al3+ and Cu2+ in acetonitrile solution by monitoring changes in the absorption and fluorescence spectral patterns. The results show that Al3+ ions can induce a greater fluorescence enhancement, while the addition of Cu2+ ions induces a strong UV–vis absorption enhancement with weak fluorescence. The limits of detection of Cu2+ and Al3+ were estimated to be 2.9 × 10−7 M and 8.3 × 10−9 M, respectively.

Chemotherapy resistance is a major obstacle to achieving durable progression-free-survival in breast cancer patients. Identifying resistance mechanisms is crucial to the development of effective breast cancer therapies. Immediate early genes (IEGs) function in the initial cellular reprogramming response to alterations in the extracellular environment and IEGs have been implicated in cancer cell development and progression. The purpose of this study was to investigate the influence of kinase inhibitors on IEG expression in breast cancer cells. The results demonstrated that Flavopiridol (FP), a CDK9 inhibitor, effectively reduced gene expression. FP treatment, however, consistently produced a delayed induction of JUNB gene expression in multiple breast cancer cell lines. Similar results were obtained with Sorafenib, a multi-kinase inhibitor and U0126, a MEK1 inhibitor. Functional studies revealed that JUNB plays a pro-survival role in kinase inhibitor treated breast cancer cells. These results demonstrate a unique induction of JUNB in response to kinase inhibitor therapies that may be among the earliest events in the progression to treatment resistance.

A novel N-(3-aminopropyl)-imidazole-appended rhodamine-based fluorescent chemosensor was synthesized. The sensing behavior and selectivity of the synthesized chemosensor toward metal cations were studied by UV/vis and fluorescence spectroscopy. The chemosensor recognized Al3+ ions by a significantly enhanced fluorescence and a visible color change due to opening of the spirolactam ring triggered by the addition of Al3+ ions.

A new infrared preprocessing modality called sequence differential processing is proposed. Different from the cold image subtraction which only decreases the background noise, the proposed modality takes the parallel test into account to preprocess the raw thermal data sequence prior to applying the advanced postprocessing techniques such as principal component thermography and pulsed phase thermography. The results show that the preprocessing method not only effectively reduces the influence of uneven laser energy distribution on detection efficiency but also enhances internal defect information. Moreover, the combination of the proposed preprocessing method with the pulsed phase thermography and principal component analysis algorithms improves the ability of laser infrared thermography to detect defects inside aviation carbon-fiber-reinforced plastics.

Mediator recently has emerged as a central player in the direct transduction of signals from transcription factors to the general transcriptional machinery. In the case of nuclear receptors, in vitro studies have shown that the transcriptional coactivator function of the Mediator involves direct ligand-dependent interactions of the MED1 subunit, through its two classical LxxLL motifs, with the receptor AF2 domain. However, despite the strong in vitro evidence, there currently is little information regarding in vivo functions of the LxxLL motifs either in MED1 or in other coactivators. Toward this end, we have generated MED1 LxxLL motif-mutant knockin mice. Interestingly, these mice are both viable and fertile and do not exhibit any apparent gross abnormalities. However, they do exhibit severe defects in pubertal mammary gland development. Consistent with this phenotype, as well as loss of the strong ligand-dependent estrogen receptor (ER)α-Mediator interaction, expression of a number of known ERα-regulated genes was down-regulated in MED1-mutant mammary epithelial cells and could no longer respond to estrogen stimulation. Related, estrogen-stimulated mammary duct growth in MED1-mutant mice was also greatly diminished. Finally, additional studies show that MED1 is differentially expressed in different types of mammary epithelial cells and that its LxxLL motifs play a role in mammary luminal epithelial cell differentiation and progenitor/stem cell determination. Our results establish a key nuclear receptor- and cell-specific in vivo role for MED1 LxxLL motifs, through Mediator-ERα interactions, in mammary gland development.

Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, a significant cause of morbidity in China and the Philippines. Here we present a draft genomic sequence for the worm, which is the first reported for any flatworm, indeed for the superphylum Lophotrochozoa. The genome provides a global insight into the molecular architecture and host interaction of this complex metazoan pathogen, revealing that it can exploit host nutrients, neuroendocrine hormones and signaling pathways for growth, development and maturation. Having a complex nervous system and a well developed sensory system, S. japonicum can accept stimulation of the corresponding ligands as a physiological response to different environments, such as fresh water or the tissues of its intermediate and mammalian hosts. Numerous proteinases, including cercarial elastase, are implicated in mammalian skin penetration and haemoglobin degradation. The genomic information will serve as a valuable platform to facilitate development of new interventions for schistosomiasis control.

Aims Cardiac injury is accompanied by dynamic changes in the expression of microRNAs (miRs). For example, miR-150 is down-regulated in patients with acute myocardial infarction, atrial fibrillation, dilated and ischaemic cardiomyopathy as well as in various mouse heart failure (HF) models. Circulating miR-150 has been recently proposed as a better biomarker of HF than traditional clinical markers such as brain natriuretic peptide. We recently showed using the β-arrestin-biased β-blocker, carvedilol that β-arrestin1-biased β1-adrenergic receptor cardioprotective signalling stimulates the processing of miR-150 in the heart. However, the potential role of miR-150 in ischaemic injury and HF is unknown. Methods and results Here, we show that genetic deletion of miR-150 in mice causes abnormalities in cardiac structural and functional remodelling after MI. The cardioprotective roles of miR-150 during ischaemic injury were in part attributed to direct repression of the pro-apoptotic genes egr2 (zinc-binding transcription factor induced by ischaemia) and p2x7r (pro-inflammatory ATP receptor) in cardiomyocytes. Conclusion These findings reveal a pivotal role for miR-150 as a regulator of cardiomyocyte survival during cardiac injury.

A recent report on the mechanism of synaptic targeting of Cav2.2 channel suggested that this process depends upon the presence of long C-terminal tail and that protein interactions mediated by SH3-binding and PDZ-binding motifs in the tail region are important. To examine the possibility that C-terminal tail of the Cav2.1 channel and the polyglutamine stretch therein are also involved in the mechanism for channel localization, we constructed several expression plasmids for human Cav2.1 channel tagged with enhanced green fluorescent protein (EGFP) and introduced them into mouse hippocampal neuronal culture. HC construct encodes short version of Cav2.1, and HS and HL encode Cav2.1 channel with a long C-terminal tail, which contains polyglutamine tract of 13 (normal range) and 28 (SCA6 disease range) repeat units, respectively. Surprisingly, transfection with HC, HS, and HL gave essentially the same results: EGFP signal was observed in cell soma, dendrites, and the axon as well. Furthermore, mutation of the PDZ-binding motif located at the C-terminus of the long version of Cav2.1, by adding FLAG tag, did not affect the localization patterns of HS and HL as well. Therefore, the C-terminal region is not indispensable for the subcellular localization of Cav2.1 channel, nor expansion of polyglutamine length affected the localization of the channel. Thus, it is possible that the localization mechanism of Cav2.1 channel is different from that of Cav2.2, though these channels share various structural and functional characteristics.

Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a close correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis.