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Lung cancer is a leading cause of cancer death in many countries. Notch signaling has been demonstrated to frequently participate in the process of lung carcinogenesis. Delta-like ligand 4 (Dll4) is a vascular-specific ligand of Notch, and has a critical role in the angiogenesis of numerous cancers. However, the role of Dll4 in the cross-talk between endothelial cells (ECs) and tumor cells remains obscure. Herein, our study revealed that Dll4-expressing ECs (EC-Dll4) significantly suppressed the proliferation of neighboring non-small cell lung cancer (NSCLC) cells and attenuated the growth of NSCLC xenograft in nude mice. On the contrary, silencing endothelial Dll4 by its specific interference RNA reversed these effects of Dll4 on NSCLC cell proliferation and tumor formation. Furthermore, activation of Notch1, but not Notch2 or Notch3, was enhanced in NSCLC cells cultured with EC-Dll4, as well as in xenografts induced by a mixture of NSCLC cells and EC-Dll4. Interference of Notch1 significantly attenuated Dll4-mediated suppression of NSCLC cell proliferations, indicating that Dll4/Notch1 signaling negatively modulates the NSCLC growth. Moreover, PTEN expression in NSCLC cells was increased by EC-Dll4 or rhDll4 (recombinant human-Dll4 protein), and the induction was impaired by Notch1 interference suggesting that Dll4 could upregulate PTEN expression by Notch1. Taken together, we conclude that the cross-talk between ECs and NSCLC cells by Dll4/Notch1/PTEN signaling pathway inhibits the growth of NSCLC.

Weather radar echo is one of the fundamental data for meteorological workers to weather systems identification and classification. Through the technique of weather radar echo extrapolation, the future short-term weather conditions can be predicted and severe convection storms can be warned. However, traditional extrapolation methods cannot offer accurate enough extrapolation results since their modeling capacity is limited, the recent deep learning based methods make some progress but still remains a problem of blurry prediction when making deeper extrapolation, which may due to they choose the mean square error as their loss function and that will lead to losing echo details. To address this problem and make a more realistic and accurate extrapolation, we propose a deep learning model called Adversarial Extrapolation Neural Network (AENN), which is a Generative Adversarial Network (GAN) structure and consist of a conditional generator and two discriminators, echo-frame discriminator and echo-sequence discriminator. The generator and discriminators are trained alternately in an adversarial way to make the final extrapolation results be realistic and accurate. To evaluate the model, we conduct experiments on extrapolating 0.5h, 1h, and 1.5h imminent future echoes, the results show that our proposed AENN can achieve the expected effect and outperforms other models significantly, which has a powerful potential application value for short-term weather forecasting.

Clinical endometritis is an important disease of dairy cattle and results in decreased reproductive performance. This disease is caused by contamination of the uterus with a broad spectrum of microorganisms after calving. In this study, staphylococcal isolates from the uterus of dairy cows with clinical endometritis were tested for their distribution of superantigen (SAg) genes and antimicrobial resistance. Between the 127 staphylococcal isolates collected in this study, 10 species were identified. The predominant strain identified was Staphylococcus aureus (n=53), followed by Staphylococcus saprophyticus (n=38) and Staphylococcus chromogenes (n=22). PCR analysis demonstrated that most isolates (63.0 per cent) harboured at least one SAg gene. The most commonly observed SAg gene and genotype was selj (38.6 per cent) and sec-selj-seln (24.0 per cent), respectively. Most isolates were resistant to penicillin (79.5 per cent), ampicillin (71.7 per cent), erythromycin (56.7 per cent), and tetracycline (52.0 per cent). PCR analysis demonstrated that the antimicrobial resistance determinants ermA, ermB, ermC, tetK, tetM and blaZ were detected in 0 per cent, 44.4 per cent, 51.4 per cent, 68.2 per cent, 13.6 per cent and 86.1 per cent of the erythromycin, tetracycline and β-lactam resistant isolates, respectively. There were 22 (17.3 per cent of all isolates) coagulase-negative staphylococci shown to be methicillin resistant. In the methicillin-resistant isolates, significant resistances to ampicillin, erythromycin and penicillin were observed (P<0.01). The results of this study demonstrate that staphylococci recovered from dairy cows with clinical endometritis contain an extensive and complex prevalence of SAg genes. Significant resistances to antibiotics were also seen, highlighting the need for the rational appliance of antibiotics in veterinary medicine.

In order to explore the effect of several common crops (wheat, corn, rice) straw on the properties of cement-based materials, the straw fiber-cement composites were prepared by dividing the straw into cement. The physical and mechanical properties of the three composites were investigated by different pretreatment methods, fiber content and fiber length. The results show that the hemicellulose content in straw decreases greatly in three pretreatment methods (cold water, 4% NaOH solution and hot alkali), and the effect of straw on retarding time of cement is weakened obviously. The increase of dimension length is disadvantageous to the mechanical strength of the composites; after pretreatment, the physical and mechanical properties of the three kinds of straw fiber-cement composites are improved. The optimum order of the three kinds of straw as cement additives is wheat > corn > rice.

Objective To describe clinical features of patients with multiple sclerosis (MS) in Shanghai, China. Methods Prevalent patients with MS were identified and investigated by a network of physicians in 11 districts of Shanghai during the period from 1 September 2004 to 31 August 2005. Admission registries of each hospital in the study area were checked systematically for patients with a diagnosis of MS, neuromyelitis optica or other demyelinating disorders. All patients with collected information were evaluated by four senior neurologists according to the McDonald criteria. Results There were 249 (146 female and 103 male) patients with a confirmed MS diagnosis, at a female-to-male ratio of 1.4. The mean age at onset of MS was 37.4 years for the 249 patients with MS and, on the prevalence day, 42.7 years. The most frequent location of clinical MS lesions in the central nervous system was the spinal cord (61%), followed by the cerebrum (55%) and optic nerves (41%). Nearly all (96%) of the patients with MS had been examined by magnetic resonance imaging, and 226 (94%) patients of those examined were suggestive of MS. No family history of MS was found in any of the patients. Most (86%) of the patients had no or mild disability on the prevalence day (31 December 2004). Almost all (96%) patients with MS had been treated with corticosteroids. Conclusion Clinical features of patients with MS are described based on the information from the largest case series reported among Chinese. Comparisons and discussions are made with findings from the other populations.

To improve the productivity of automated forging production units, reasonable layout is very important. In this paper, the layout optimization method of the robot working unit was studied to improve the production efficiency of forged crankshaft products, the bottleneck production unit is taken as the research object to find a satisfactory solution to the layout planning. Based on a mathematical model, a hierarchical description method of robot workspace and a prediction method of transition points were proposed. The robot running time and operability were used as evaluation indexes of the layout. The NSGA-II algorithm was used to optimize the layout scheme to obtain a better solution, and the optimized solution has better operability and runtime performance. The simulation results of professional software showed that the proposed layout optimization method and layout scheme were reasonable and significantly improved.

The rising attention to Moon-based Earth observation provides a new way to monitor Earth. Among Moon-based detectors, the SAR method has the advantage of long-term, stable, unique observations compared to space-borne SAR. Unlike space-borne SAR, however, the complicated relative motion of a Moon-based sensor makes its Doppler centroid estimation more difficult. This paper proposes a method for two-dimensional attitude steering to compensate for the Doppler centroid of Moon-based SAR. In the periodic movement between Earth and the Moon, the track speed of sites distributed around the near side of the Moon are almost perpendicular to vectors from the sites to the Earth centroid. This situation indicates the feasibility of attitude steering to guide antennas into a zero Doppler plane intersecting Earth’s surface. Therefore, this paper proposes a method for two-dimensional attitude steering to compensate the Doppler centroid to zero. In this method, the Moon is no longer deemed as a point but a natural celestial body with an average radius. Sites distributed around the hemisphere of the near side are also considered separately because of differences in spatial position and speed. Through the proposed method, the pointing of SAR antennas will be steered to a place on Earth where the Doppler centroid is compensated to zero. The JPL DE430 and EOP data are closer to reality and are used for accurate simulation. In this paper, the twodimensional attitude steering method is compared with no attitude steering and a onedimensional attitude steering method, and the results show its effectiveness.

Metamaterial absorber (MMA) has great potential application in many scientific and technical fields due to its perfect absorption characteristics. For most practical applications, the absorption bandwidth is one of the most important performance metrics. In this paper, we demonstrate a design of wideband tunable MMA based on graphene. The proposed absorber shows tunable wideband absorption at different externally applied voltage. The simulated absorption exceeds 90% from 7.6 THz to 8.5THz and the full width at half maximum is 75% (from 7.505THz to 8.705THz), which is achieved by using a single layer of multiple SRRs. Further study demonstrates that the absorption wideband can be greatly tuned by applying different externally applied voltage. The absorption band shifts to lower frequency with the increasing of externally applied voltage. This work opens up the possibility for designing intelligent terahertz active filter.

A kind of wideband metamaterial absorber at E band is designed in this paper; it is composed of round metal cells with defect, dielectric substrate and metal film. The electromagnetic parameters of unit cell are calculated by using the finite element method. The results show that the wideband metamaterial absorber presents nearly perfect absorption above 90% with absorption ranging from 65.38GHz to 67.86GHz; the reason of wideband absorption is the overlap of different absorption frequency which is caused by electromagnetic resonance; the size parameters and position of defect has important effect on its absorption property. It has many advantages, such as simply, easy to preparation and so on. It has potential application on aerospace measurement and control, remote data communication, LTE wideband mobile communication and other fields.

The experimental microgrid could provide a platform for operation and testing of the tested microgrid, so that the performance of the tested microgrid could be obtained before it was put into use. The microgrid had different structures, configurations, distributed generations and three-phase unbalanced load, so the voltage, current and power of the experimental microgrid would inevitably oscillate. First, the power oscillations mechanism of multi-source microgrid was deeply analysed, that was, the analytical relationship between active power pulsation and reactive power pulsation was derived and the influence of positive and negative sequence electrical quantities on power pulsation was revealed. Then, a power oscillations suppression strategy based on power optimal control was proposed. Finally, we built a multi-source microgrid simulation model and a power oscillations control system simulation model on MATLAB. The results showed that the control strategy proposed in this paper could significantly reduce the amplitude of power oscillations caused by unbalanced voltage and current. It could be verified that the control strategy was correct and effective.