357 research outputs found

    Effect of Forage Brassica on Subsequent Soil Water Content and Yield of Dual-Purpose Winter Wheat in Rainfed Region of Northwestern China

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    The dual-purpose performance of winter wheat used for both forage and grain production has been explored as an alternative practice for filling the feed gap during winter and spring in agricultural areas of the Loess Plateau. Profit-ability is still restricted however, because of a three month summer fallow period between harvest and planting of the subsequent wheat crop. During this 3 month period 60% of the annual precipitation occurs, limiting the effective use of soil water and compounding the risk of soil erosion. Thus it is important to cultivate some forage crops with higher water consumption, protecting the ecological environment during this period and enlarging the forage resource base through their high forage yield and good quality. A previous study has shown that inclusion of rapeseed into crop rotations could reduce disease in subsequent plantings, leading to an increase in production of the following wheat crop (Brendan and John 2004). Accordingly, dual-purpose winter wheat after forage brassica may be an effective option to meet these requirements. Other studies have shown however, that wheat yield of grazed plots following brassica was reduced by 29% compared with that of grazed plots following fallow, and that average grain yield in grazed plots was reduced by 38% compared with that in ungrazed plots (Kelman and Dove 2007). Additionally, the possibility of severe water stress occurring after forage crop harvest is an important concern. In this study, soil moisture status and forage and grain yield of dual-purpose winter wheat following forage brassica were investigated and compared with those of winter wheat after fallow

    Retrieval of Raindrop Size Distribution, Vertical Air Velocity and Water Vapor Attenuation Using Dual-Wavelength Doppler Radar Observations

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    Two techniques for retrieving the slope and intercept parameters of an assumed exponential raindrop size distribution (RSD), vertical air velocity, and attenuation by precipitation and water vapor in light stratiform rain using observations by airborne, nadir looking dual-wavelength (X-band, 3.2 cm and W-band, 3.2 mm) radars are presented. In both techniques, the slope parameter of the RSD and the vertical air velocity are retrieved using only the mean Doppler velocities at the two wavelengths. In the first method, the intercept of the RSD is estimated from the observed reflectivity at the longer wavelength assuming no attenuation at that wavelength. The attenuation of the shorter wavelength radiation by precipitation and water vapor are retrieved using the observed reflectivity at the shorter wavelength. In the second technique, it is assumed that the longer wavelength suffers attenuation only in the melting band. Then, assuming a distribution of water vapor, the melting band attenuation at both wavelengths and the rain attenuation at the shorter wavelength are retrieved. Results of the retrievals are discussed and several physically meaningful results are presented

    PSYCHOSOCIAL FACTORS LEAD TO DELINQUENCY ITENTION ON ONLINE PEER-TO-PEER LENDING PLATFORM: A SURVEY EVIDENCE

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    In recent years, online P2P lending grows remarkably. Past studies mainly used direct second-hand data from P2P platforms to conclude many factors are related to people\u27s delinquency and default behaviours, lacking further exploration on how people\u27s social and psychological status could impact their behaviour during the borrowing and repayment process. On foundation of general strain theory (GST) and the model of frame selection (MFS), we used survey method and collected data from more than 700 Chinese subjects. A two-stage structural equation model was proposed. In the first stage, we investigated how people\u27s psychosocial factors (e.g. economic capacity, sense of fairness and sociability etc.) could shape their individual feelings and attitudes in social context (e.g. life satisfaction and self-esteem) as well as morality. In the second stage, we tested the relationship between life satisfaction, self-esteem, moral norm and people\u27s delinquency intention on P2P lending platform. The empirical results suggest that higher psychosocial status will be conductive to better individual feelings of life satisfaction and self-esteem. Moreover, better psychosocial factors will mostly lead to a higher moral norm of people. Therefore, these favourable feelings and morality further contribute to less delinquency intention on P2P lending platform. Our research has both academic and practical implications

    The Role of Alfalfa and Forage Resources in Crop-Livestock Systems in a Rain-Fed Region of North-Western China

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    Western China has been facing the challenges of both environmental sustainability and economic development. Current government policies and interventions support the development of integrated crop-livestock production systems for enhancing food security and environment sustainability. Compared with traditional grain-based faming systems, integrated systems have better resource utilisation, however annual forage supply deficits estimated at 1.37 t DM forage/farm are experienced in the region, especially in late winter and early spring. Accordingly, optimising the use of available forage resources is a priority for regional researchers and extension officers, with research seeking pathways for better fodder conservation and greater and more effective use of fodder sources to close the spring feed gap. This paper presents relevant research activities relating to alfalfa (Medicago sativa L.) and winter wheat (Triticum aestivum L.) management in integrated crop-livestock production systems. As the planting of alfalfa is strongly encouraged in northern China, alfalfa species selection and optimised harvesting management are essential to ensure the full benefits of alfalfa are available for livestock intensification. The capacity for a prevalent grain crop, winter wheat to be managed as a dual-purpose fodder and grain source shows potential as a means to alleviate deficits of animal feed supply. The present information expands our understanding of integrated forage-livestock production in rain-fed areas, exploring options that can improve productivity in small-farm households leading to income generation

    Analysis of influencing factors of multiple urethrocutaneous fistula after urethroplasty in children with hypospadias

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    ObjectiveThe objective of this study was to investigate the influencing factors of multiple urethrocutaneous fistula (UF) after urethroplasty in children with hypospadias.MethodsThe clinical data of 195 children with UF after urethroplasty treated surgically in the Third Affiliated Hospital of Zhengzhou University from August 2015 to August 2022 were retrospectively analyzed and divided into the single UF group (n = 134) and the multiple UF group (n = 61) according to whether multiple UF occurred after urethroplasty. The possible correlated factors were collected and compared between the two groups, including hypospadias degree, length of formed urethra, time of urethroplasty, pre-urethroplasty weight, age at urethroplasty, urethroplasty style, season of urethroplasty, the first fistula repair method, season of the first fistula repair, diameter of the largest fistula of the first fistula repair, time of the first fistula repair surgery, and other 13 factors.ResultsBy univariate analysis, statistically significant differences were found between the two groups in age at urethroplasty, length of the formed urethra, method of urinary drainage after urethroplasty, whether or not purulent urethral drainage after first fistula repair was present, the first fistula repair method, and diameter of the largest fistula of the first fistula repair (P < 0.05). After multifactorial analysis, the independent risk factors associated with multiple UF after urethroplasty were determined to be use of a vesicostomy tube as the urinary drainage method after urethroplasty (P < 0.05, OR = 6.574, 95% CI: 2.720–15.891) and the presence of purulent urethral drainage after first fistula repair (P < 0.05, OR = 2.723, 95% CI: 1.214–6.109).ConclusionsA catheter as the drainage method after urethroplasty is an independent protective factor for multiple urethrocutaneous fistula, and the existence of purulent urethral secretions after the first fistula repair is an independent risk factor

    Airborne Radar Observations of Severe Hailstorms: Implications for Future Spaceborne Radar

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    A new dual-frequency (Ku and Ka band) nadir-pointing Doppler radar on the high-altitude NASA ER-2 aircraft, called the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP), has collected data over severe thunderstorms in Oklahoma and Kansas during the Midlatitude Continental Convective Clouds Experiment (MC3E). The overarching motivation for this study is to understand the behavior of the dualwavelength airborne radar measurements in a global variety of thunderstorms and how these may relate to future spaceborne-radar measurements. HIWRAP is operated at frequencies that are similar to those of the precipitation radar on the Tropical Rainfall Measuring Mission (Ku band) and the upcoming Global Precipitation Measurement mission satellite's dual-frequency (Ku and Ka bands) precipitation radar. The aircraft measurements of strong hailstorms have been combined with ground-based polarimetric measurements to obtain a better understanding of the response of the Ku- and Ka-band radar to the vertical distribution of the hydrometeors, including hail. Data from two flight lines on 24 May 2011 are presented. Doppler velocities were approx. 39m/s2at 10.7-km altitude from the first flight line early on 24 May, and the lower value of approx. 25m/s on a second flight line later in the day. Vertical motions estimated using a fall speed estimate for large graupel and hail suggested that the first storm had an updraft that possibly exceeded 60m/s for the more intense part of the storm. This large updraft speed along with reports of 5-cm hail at the surface, reflectivities reaching 70 dBZ at S band in the storm cores, and hail signals from polarimetric data provide a highly challenging situation for spaceborne-radar measurements in intense convective systems. The Ku- and Ka-band reflectivities rarely exceed approx. 47 and approx. 37 dBZ, respectively, in these storms
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