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Because the designed frequency band of Geosynchronous synthetic aperture radar(GEO SAR) satellite signal possibly shares or overlaps with the frequency band of various Global Navigation Satellite System(GNSS) signals which have been put into use, the ground GNSS receiver may be subject to the pulse radio frequency interference generated by GEO SAR signal. In order to evaluate the influence of GEO SAR signal on the performance of GNSS ground receiver, a parametric theoretical model based on International Telecommunication Union(ITU) related standards is proposed in this paper. The model uses the "source-path-receiver" analysis method to extract parameters from the three aspects of GEO SAR signal, signal propagation path and receiver model for interference evaluation. Then, according to ITU standards, the influence of high-orbit SAR signal as additive pulse radio frequency interference on the performance of GNSS receiver is evaluated. Taking the representative B3I signal as an example, this paper evaluates the performance of different types of B3I receivers for GEO SAR signal under the condition of the assumed design parameters. The results show that the performance of the receiver decreases slightly in the presence of high-orbit SAR signal interference, but it can still work normally.

Doppler shift is an important measurement for localization and synchronization (LAS), and is available in various practical systems. Existing studies on LAS techniques in a time division broadcast LAS system (TDBS) only use sequential time-of-arrival (TOA) measurements from the broadcast signals. In this paper, we develop a new optimal LAS method in the TDBS, namely LAS-SDT, by taking advantage of the sequential Doppler shift and TOA measurements. It achieves higher accuracy compared with the conventional TOA-only method for user devices (UDs) with motion and clock drift. Another two variant methods, LAS-SDT-v for the case with UD velocity aiding, and LAS-SDT-k for the case with UD clock drift aiding, are developed. We derive the Cramer-Rao lower bound (CRLB) for these different cases. We show analytically that the accuracies of the estimated UD position, clock offset, velocity and clock drift are all significantly higher than those of the conventional LAS method using TOAs only. Numerical results corroborate the theoretical analysis and show the optimal estimation performance of the LAS-SDT.

The oasis-desert transition zone (TZ) is an ecological buffer zone between a mobile desert and an oasis, which are important in reducing the forward mobility of sand dunes and wind and sand hazards in an oasis. In this study, the Dunhuang Oasis and its TZ in the Hexi Corridor (China) were examined. Based on the annual normalized vegetation index (NDVI) at each buffer distance of the TZ from 1987 to 2015, combing the watershed hydrology, oasis crop cultivation structure and industrial economic status, partial least squares regression models and a correlation analysis were used to examine the spatial and temporal changes in the vegetation gradient of the oasis TZ and the factors influencing those changes. (1) Spatially, the NDVI values in the TZ generally decreased gradually before stabilizing with a buffer distance (average decrease of 0.01–0.03 per 300 m). (2) Temporally, the mean values of the NDVI in the TZ show an overall wavelike variation across years. The annual average maximum NDVI value was 0.11 in 1987, whereas the annual average minimum value was 0.07 in 2014. (3) During the 1987–2015, runoff, tourist populations and water consumption for orchards were significantly and positively correlated with the NDVI; the year-end arable land area and the total industrial output value were significantly and negatively correlated with the NDVI; the rural per capita net income and water consumption for grain planting were not significantly and positively correlated with the NDVI; water consumption for the sum of vegetable and melon planting, water consumption for cotton planting, urbanization and rural populations were not significantly and negatively correlated with the NDVI. (4) The farm TZ NDVI is more strongly influenced by human activities than the undisturbed natural TZ.

Based on the solvothermal method, two new MOFs with 3-(1-Oxo-1H-2,3-dihydroisoindol-2-yl)benzoic acid as the organic ligand, Zn-HBPA and Zn-bpy-HBPA were synthesized. The structure of MOFs was characterized by 1H-NMR, XRD, FT-IR and SEM. A series of modified cellulose paper-based functional materials with different spraying times were prepared by flame spraying method, and the fluorescence property of MOFs modified cellulose paper to EtOH small molecules was investigated by fluorescence spectrometer. The results of FT-IR and SEM showed that the flame spraying method could effectively improve the retention rate of MOFs on cellulose paper materials. The PL characterization results displayed that Zn-HBPA@PFP exhibited a decrease in fluorescence after UV irradiation, while Zn-bpy-HBPA@PFP demenstrated an increase in fluorescence at λ=338 nm. The above results indicated that Zn-bpy-HBPA@PFP had an excellent response ability to EtOH small molecules, and when Cycle=7 times, Zn-bpy-HBPA@PFP had the best fluorescence enhancement effect.

Peyronellaea arachidicola is the causal agent of peanut (Arachis hypogaea L.) web blotch. Here, we report an assembled draft genome sequence of P. arachidicola strain YY187 obtained from the symptomatic leaf of peanut in China. The genome size is 47.3 Mb, consisting of 26 contigs (N50 = 2.2 Mb) with G+C content of 56.37%. This genome will provide a valuable foundation for further research on genetics and comparative genomics of P. arachidicola.

Botrytis cinerea (teleomorph: Botryotinia fuckeliana) is an airborne, necrotrophic ascomycete plant pathogen, which has been reported to infect over 200 crop hosts worldwide (Boddy 2016; Kim et al. 2016). B. cinerea can cause severe damage to plants, such as gray mold on leaves or rot on fruit, both pre- and postharvest (Dean et al. 2012). In September 2015, brown, irregular-shaped lesions were observed on peanut leaves from Jilin province in China. Disease incidence in approximately a 10-ha area in each of 15 examined fields was 20 to 30%. Symptoms were initially observed on the apex and/or margin of the older leaves, were not restricted by the leaf veins, and enlarged to result in leaf necrosis and defoliation. Symptomatic leaf samples were collected, surface sterilized (75% ethanol, 30 s; 3% NaClO, 2 min), rinsed in sterile water three times, and air dried; small sections were plated on potato dextrose agar (PDA) medium and incubated at 25 ± 1°C (12-h photoperiod). Colonies on PDA medium were initially gray and covered the entire plate with aerial mycelium in 2 days. Black sclerotia were first observed at the edge of colonies after 3 days and then formed unevenly among the colonies after 6 days. Conidia were transparent, elliptical or ovoid, and measured 4.4 to 8.6 µm long × 3.4 to 5.8 µm wide (n = 50). For pathogenicity tests, a conidial suspension (10⁵ conidia/ml) was sprayed onto leaves of peanut plants grown in five 16 × 12-cm pots with six plants per pot. A similar number of plants were inoculated with sterile water to serve as controls. Inoculated plants were incubated in a growth cabinet with a high relative humidity (80%) for 72 h at 25°C, followed by 60 to 70% relative humidity at 25°C with a 12-h photoperiod of dark and light. Symptoms on leaves emerged between 7 and 10 days and were similar to those described on the field-collected leaves, whereas no symptoms were observed on the control plants. The pathogen that was reisolated from the inoculated leaves using the same method described above had the same morphology on PDA medium as described above. As for molecular identification, the internal transcribed spacer (ITS) and three nuclear protein-coding genes (glyceraldehydes-3-phosphate dehydrogenase gene [G3PDH], heat-shock protein 60 gene [HSP60], and DNA-dependent RNA polymerase subunit gene [RPB2]) were amplified using primer pairs ITS1/ITS4 (White et al. 1990), G3PDH-F/G3PDH-R, HSP60-F/HSP60-R, and RPB2-F/RPB2-R (Staats et al. 2005), respectively. The sequences were submitted to GenBank (ITS, MN272329; G3PDH, MK791186; HSP60, MK791187; RPB2, MK791188). BLASTn analysis showed 500/501, 994/994, 1,120/1,120, and 1,240/1,240 base pairs matched with sequences of B. cinerea deposited for ITS (MH763647), G3PDH, (MH479930), HSP60 (MH796663), and RPB2 (MH713610), respectively. To our knowledge, this is the first report of B. cinerea found on peanut plant in China. B. cinerea usually causes soft rotting of aerial plant parts and postharvest rotting of vegetables, fruits, and flowers (Williamson et al. 2007). The threat of this pathogen to peanut pods needs to be further investigated, because it could potentially lower the peanut quality and may be a threat to human health.

Ginseng is a traditional Chinese medicine with a wide range of pharmacological activities. Ginsenosides are the major constituents of ginseng. Ginsenosides have the unique biological activity and medicinal value, such as antitumor, anti-inflammatory, antioxidation, and inhibition of cell apoptosis. With the increase of stress in life, the incidence of nervous system diseases is also increasing. Neurological diseases pose a huge burden on people’s life and health. In recent years, some studies have shown that ginsenosides have a certain role in the prevention and treatment of neurological diseases. However, the research is still in its infancy, and the relevant mechanisms are complex. In the paper, we review the effects and mechanisms of ginsenosides on epilepsy, depression, cerebral ischemia reperfusion injury, Alzheimer’s disease, and Parkinson’s disease. We hope to provide a theoretical basis for the treatment of nervous system diseases by ginsenosides.

Positioning with one single communication between base stations and user devices can effectively save air time and thus expand the user volume to infinite. However, this usually demands accurate synchronization between base stations. Wireless synchronization between base stations can simplify the deployment of the positioning system but requires accurate clock offset estimation between base stations. A time division multiple access (TDMA) localization system in which user devices only receive signals from base stations to generate time of arrival (TOA) measurements to position themselves and no cables are needed to interconnect base stations for clock synchronization is proposed, implemented and tested. In this system, the user devices can easily join in or exit without influence to other users and the update rate of each user can be easily adjusted independently according to its specific requirement.

Virtual reality (VR) related technologies have been regarded as a future hotspot in various kinds of application areas. In most of the existing VR game systems, players have to stay at a fixed location wearing a head-mounted display (HMD) and interact with the moving virtual scenarios, which may cause the feeling of sickness. VR games that uses a localization system enable the players to move inside a specific area which enhances the sense of immersion. However, due to the imprecise position information that cannot correctly reflect the user movement, players still feel dizzy. In order to solve this problem, we develop an indoor navigation system and propose a localization algorithm for VR game applications to provide accurate and smooth positioning information for virtual environment generation so that players can move in the real world and interact with the virtual scenario that is consistent with their real positions and movements. We implement this system with both ranging devices based on ultra wide band (UWB) technology and inertial measurement unit (IMU). Extended Kalman Filter (EKF) is applied in the positioning algorithm to fuse the range and IMU measurements. Zero velocity update (ZUPT) correction and robust estimation to detect and remove outliers are also used in our algorithm. Experiments in indoor environment prove that the algorithm can provide positioning results accurately and smoothly.

Using molybdenum tailings in Shangluo as a core sample and the cement as gelled material, the unfired brick is prepared by mixing molybdenum tailings, cement, sand, silica powder and accelerating admixture, and then stirring and vibration. The effects of molybdenum tailings content, the ratio of molybdenum tailings to river sand and the addition of the silica powder on mechanical properties of the unfired brick. Results show that With the addition of molybdenum tailings increased, the mechanical properties of the unfired brick was decreased. When the addition of molybdenum tailings is below 75%, the flexural strength and compressive strengh are above 4.83MPa and 15.69MPa respectively, it meets MU15 standard. With the ratio molybdenum tailings to river sand increasing, the mechanical properties decreased firstly, and then increased. The mechanical properties of unfired brick is decreased with increasing of the silica powder.

Peanut is an economical crop of global importance and grown widely in both tropics and subtropics. Currently, China is the largest peanut production, consumption and trade countries around the world. In August 2014, light-brown foliar spots with dark brown, irregular borders were found on peanut (Yuhua 22) at Xinyang in Henan province, China. Symptomatic leaf samples were collected, and surface-sterilized (75% ethanol, 30 s; 3% NaClO, 2 min), rinsed in sterile water for three times, air-dried, plated on potato dextrose agar (PDA) medium, and incubated at 25°C under a 12-h dark/light cycle. Colonies on PDA were initially gray, fluffy mycelium with unevenly distributed mycelial pellets, then becoming dark gray with age. Conidia were oblong, slightly curved, and light-brown with 6 to 10 septa. Conidial sizes (length × width) were 57.5 to 144.7×8.4 to 21.4 (average 102.0×13.8) μm. Pathogenicity tests were conducted with 6-week-old peanut plants. Ten 16×12-cm pots with six plants per pot were inoculated onto t...

Multilayered space-time coded modulation is an approach of combining array processing and space-time coding. Because different coded layers have different diversity gain, so unequal power levels should be allocated to the different coded layers for achieving best performance. This paper transforms the power allocation problem into two standard optimization problems. Simulation results demonstrate that new power allocation is 2/spl sim/2.5 dB better than equal power manner and 0.5/spl sim/1 dB better than experimental scheme in Tarokh et al. [May 1999].

Fairness of resource allocation scheme is very important for realizing quality of service (QoS) in Internet. However, the current scheme implementing TCP protocol is unfair for the users with different round trip times (RTTs). In this paper; we introduce a new model based on dynamic congestion price that can guarantee fairness of allocating resource between users with different RTTs. Thereby, the scheme on this model can provide differential services easily.