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C28H28N10O6Cu, triclinic, P1‾$P\bar{1}$ (no. 2), a = 8.6869(7) Å, b = 9.0094(6) Å, c = 9.5839(8) Å, α = 74.288(7)°, β = 87.672(9)°, γ = 76.110(7)°, V = 700.69(11) Å3, Z = 1, Rgt(F) = 0.0492, wRref(F2) = 0.0979, T = 293(2) K.

Reproductive systems play an important role in the ecological function of species, but little is known about how climate change, such as global warming, may affect the reproductive systems of microbes. In this study, 116 Phytophthora infestans isolates sampled from five different altitudes along a mountain were evaluated under five temperature regimes to determine the effects of historical and experimental temperature on the reproductive system of the pathogen. Both altitude, a proxy for historical pathogen adaptation to temperature, and temperature used in the experiment affected the sexual reproduction of the pathogen, with experimental temperature, that is, contemporary temperature, playing a role several times more important than historical temperature. Furthermore, the potential of sexual reproduction, measured by the number of oospores quantified, increased with the temperature breadth (i.e., difference between the highest and lowest temperature at which sexual reproduction takes place) of the pathogen and reached the maximum at the experimental temperature of 21°C, which is higher than the annual average temperature in many potato‐producing areas. The results suggest that rising air temperature associated with global warming may increase the potential of sexual reproduction in P. infestans. Given the importance of sexuality in pathogenicity and ecological adaptation of pathogens, these results suggest that global warming may increase the threat of P. infestans to agricultural production and other ecological services and highlight that new epidemiological strategies may need to be implemented for future food security and ecological resilience. [ABSTRACT FROM AUTHOR]

Objective This study aimed to investigate the epidemiology and changes in antibacterial susceptibility of children in Shenmu City, northern Shaanxi, and provide a basis for rational drug use. Methods The distribution and drug resistance pattern of pathogenic bacteria isolated from children were retrospectively analysed. Results A total of 573 strains of pathogens were cultivated. A total of 201 (35.07%) strains of Gram-positive cocci and 183 (31.93%) strains of Gram-negative cocci were detected. A total of 189 (32.98%) strains of fungi were detected. The resistance rate of Staphylococcus to penicillin was 100% and that to erythromycin was 90.69%. There were varying degrees of resistance to other drugs, but no single strain had vancomycin resistance. Gram-negative bacilli were generally resistant to ampicillin, but had low resistance to the combined preparation of enzyme inhibitors, quinolones, and aminoglycosides, and were highly sensitive to imipenem and meropenem. Conclusion Gram-negative bacilli are the main pathogens of bacterial infection in the paediatric ward. Strengthening clinical monitoring of bacterial distribution in paediatric clinical isolates and understanding changes in drug resistance are important for guiding the rational use of antibiotics. These measures could also prevent emergence and spreading of resistant strains.

Airborne array antenna SAR is used to obtain three-dimensional imaging; however it is impaired by motion errors. In particular, rotation error changes the relative position among the different antenna units and strongly affects the image quality. Unfortunately, the presently available algorithm can not compensate for the rotation error. In this study, an airborne array antenna SAR three-dimensional imaging model is discussed along with the effect of rotation errors, and more specifically, the yaw angle error. The analysis reveals that along- and cross-track wavenumbers can be obtained from the echo phase, and when used to calculate the range error, these wavenumbers lead to a target position irrelevant result that eliminates the error's spatial variance. Therefore, a wavenumber-domain subblock compensation method is proposed by computing the range error in the subblock of the along- and cross-track 2-D wavenumber domain and precisely compensating for the error in the space domain. Simulations show that the algorithm can compensate for the effect of yaw angle error.

The concept of Geosynchronous Circular SAR (Geo-CSAR) is introduced in this paper. With the design of the geosynchronous orbit parameters, a near-circular satellite sub-track could be formed to enable the staring imaging mode, which supports the advanced applications for wide-field and 3-D information acquisition under long-term consistent observation. This paper also analyzes Geo-CSAR's imaging formation capabilities, and concludes its attractive advantages over low-earth orbit spaceborne SAR in terms of instantaneous coverage, consistent observing area, 3-D positioning accuracy and etc.. Encouraging expectations for Geo-CSAR thus could be positively predicted in military investigation and disaster monitoring management applications.

C22H22N2O9, monoclinic, P21/c (no. 14), a = 7.7374(3) Å, b = 29.1082(11) Å, c = 8.7595(3) Å, β = 96.853 (3) ∘ , V = 1958.74(13) Å3, Z = 4, Rgt(F) = 0.0520, wRref (F2) = 0.1501, T = 100 K. [ABSTRACT FROM AUTHOR]

Density Tapered Arrays (DTA) with nonperiodic spaced elements have many interesting features when compared to traditional DTA in which antenna elements are located only at the intersections of periodic grid; however, a design method is yet to be fully develoed. A new approach is presented using Centroidal Voronoi Tessellations (CVT) to design DTA with nonperiodic element distributions proportional to the desired amplitude taper and with nonperiodic and ‘uniform’ properties. A 32.8λ diameter circular aperture array with 1656 elements is discussed and theoretical patterns are computed for density tapers modeled after −25 dB,−30 dB,−35 dB, and −40 dB circular Taylor distributions. The obtained sidelobe levels and aperture efficiency are better than heretofore reported.

The Array 3D SAR has the ability of resolving imaging in three dimensions using the novel combination of linear array antennas and synthetic aperture. A practical array SAR system has the problem of multi-channel amplitude and phase errors, which can degrade the quality of the reconstruction image. The echo model with amplitude and phase errors is presented. The effect of each errors are analyzed and a calibration method based on Single Prominent Point Like Target Echo Data is proposed. For the application of 3D imaging, the range migration algorithm with calibration scheme is also proposed. Simulations and real data processing are performed to validate the proposed calibration scheme.

Combined with Frequency-Modulated Continuous-Wave (FMCW) technology, airborne forward-looking Synthetic Aperture Radar (SAR) with linear array antennas can obtain the image in front of the aircraft and also have the advantages of FMCW radar such as small size and lightweight. Moreover, it is suitable to be installed on platform like helicopter and small unmanned aerial vehicle. Motion compensation for forward-looking SAR with linear array antennas is one of the key problems to obtain the image in front of the aircraft in practice. This paper analyses the influence of motion error in aircraft on echo model based on the geometry of forward looking SAR with linear array antennas, and proposes a motion compensation scheme. Moreover, the compensation scheme is applicable to an improved frequency scaling algorithm (FSA) for FMCW forward looking SAR with linear array antennas. Finally, the compensation scheme is verified with the simulation.

The experiment was to investigate the effect of alfalfa meal replaced by silage with equal dry matter on growth performance, nutrient apparent digestibility and antioxidant performance of meat rabbits. A total of 100 rabbits with similar body weight and age of (30±2) days were randomly divided into five groups: Control group (no silage alfalfa), group A (8% silage alfalfa), group B (12% silage alfalfa), group C (16% silage alfalfa) and group D (20% silage alfalfa), with 20 replicates in each group and one rabbit in each replicate. The pre-test period lasted for 5 d and the formal test period lasted for 35 d. The results showed that compared with control group, the average daily gain, final weight and apparent digestibility of crude fat, acid detergent fiber, crude protein and crude fiber of meat rabbits in group B were significantly increased (P<0.05), and feed to gain ratio was significantly decreased (P<0.05). The content of MDA in serum and muscle of meat rabbits in group B was significantly decreased (P<0.05), while SOD, GSH-Px and T-AOC were significantly increased (P<0.05). The experiment indicates that using a certain proportion of equal dry matter alfalfa silage instead of alfalfa meal can improve the growth performance, nutrient apparent digestibility, antioxidant capacity of serum and muscle of meat rabbits, and the replacement proportion of 12% is better. [ABSTRACT FROM AUTHOR]