Evaluation of the management practice for controlling herbicide runoff from paddy fields using intermittent and spillover-irrigation schemes

Two water management practices, an intermittent irrigation scheme using automatic irrigation system (AI) and a spillover-irrigation scheme (SI), were compared for the fate and transport of commonly used herbicides, mefenacet (MF) and bensulfuron-methyl (BSM) in experimental paddy plots. Maximum mefenacet concentrations in paddy water were 660 and 540 μg L⁻¹ for AI and SI plot, respectively. The corresponding values for bensulfuron-methyl were 46.0 and 42.0 μg L⁻¹. Dissipation of the herbicides in paddy water appeared to follow the first-order kinetics with half-lives (DT₅₀) of 1.9–4.5 days and DT₉₀ (90% mass dissipation) of 7.8–11.3 days. The AI plot had no surface drainage, hence no herbicide was lost through paddy-water discharge. However, SI plot lost about 38 and 49% of applied mefenacet and bensulfuron-methyl, respectively. The intermittent irrigation scheme using automatic irrigation system with a high drainage gate was recommended to be a best management practice for controlling the herbicide losses from paddy fields. The paddy field managed by spillover-irrigation scheme may cause significant water and herbicide losses depending on the volume of irrigation and precipitation. The water holding period after herbicide application was suggested to be at least 10 days according to the DT₉₀ index.     

嘉道年间河费使用问题探析

论述了嘉道时期河费激增的概况及其使用效率问题,认为河费除了治河所必需的部分以外,在清代形成了一个仰食河费的庞大社会阶层,影响了河费的正常使用。     

浅谈战略转型条件下海南橡胶资产的保护

对番木瓜传统的单芽腹接法种苗繁殖进行芽接技术的创新研究，并采用3种嫁接方法进行比较试验。结果表明：不同品种的番木瓜采用创新研究技术的单芽腹接创新法的发芽率为67.50%，比传统单芽切接法高23.6%；单芽腹接创新法比切接法的发芽率高14.8%；芽接技术的创新研究取得了突破性进展，其研究结果对番木瓜产业化的发展具有重要的促进作用。     

Kinetic analysis of oxytetracycline residues in Chinese mitten crab,Eriocheir sinensis,muscle following intramuscular administration

Crab culture is a very important economic industry in China. An epidemic of tremor disease of Chinese mitten crabs, Eriocheir sinensis, has become a serious problem in recent years. A spiroplasm has been proved to be the causative agent of this disease. Oxytetracycline (OTC) is used widely in aquaculture and was confirmed to be very effective against this pathogen. In this study, the distribution and depletion patterns of OTC in crab muscle were evaluated following single intramuscular doses of 2, 8 and 40 mg kg^?1 body weight. OTC was detected with a validated HPLC method. Concentration–time profiles were well described by a three‐compartment model with first‐order absorption after a single dose of 8 and 40 mg kg^?1. For comparison, a non‐compartment model was employed. A withdrawal time of 48.29 and 55.92 days was suggested prior to consumption after receiving 8 and 40 mg kg^?1. A recommended therapeutic dose of OTC in theory was calculated to be 36.37 mg kg^?1. OTC was distributed well throughout the body. The elimination of OTC in muscle was slower compared with fish and other crustaceans. A dose of 40 mg kg^?1 is suggested for practical use.     

诱导Badila提早开花的主要气象因子初探

通过连续两年人工诱导结果表明，提早诱导时间、暗期气温高低、光照期间破坏性高温天数是诱导Badfla提早开花的主要原因。     

橡胶树种子短期贮藏最佳环境条件的研究

利用正交试验在人工气候箱内对橡胶树种子短期贮藏过程中的温度、湿度、包膜度最佳组合进行研究,通过对不同处理条件下种子的发芽率、超氧化物岐化酶(SOD)活性、电导率、碱性磷酸酶等指标的测定分析和比较,建议生产实践中,橡胶树种子短期贮藏最佳的温度、湿度和包膜度应为19℃～22℃、95％、65％～75％.     

经理人长期激励方案与股东利益的一致性研究

假设供应商向零售商提供信用支付期的同时，零售商也向顾客提供信用支付期, 研究了两货栈的变质物品库存模型，并讨论了模型最优解的唯一性, 最后给出了最优订购策略的算法步骤与数值例子.     

果树有效授粉期研究进展

为给果树栽培和育种确定最佳授粉时期提供科学依据,综述了自果树有效授粉期概念提出至今的相关研究概况,阐述了柱头可授性、花粉管动力学与胚珠寿命这三个重要参数对果树有效授粉期的意义,概述了花器官败育、胚珠发育迟缓、自交不亲和性、温度及营养水平等内外因子对这三个主要参数的影响情况,在此基础上对果树有效授粉期的研究前景进行了展望,并分析了其在育种和栽培上的指导意义。     

Preemptive Analgesia,Including Morphine,Does Not Affect Recovery Quality and Times in Either Pain-Free Horses or Horses Undergoing Orchiectomy

Recovery quality and times from general anesthesia in horses may be influenced by surgery, analgesia with morphine or combinations of both. Twenty-three adult healthy horses were enrolled in this prospective experimental trial in a clinical setting and were randomly allocated to one of the following groups: anesthesia only (GA; n = 6), preemptive analgesia and anesthesia (GAA; n = 5), anesthesia and castration (GC; n = 6), or preemptive analgesia, anesthesia, castration, and intraoperative local analgesia (GCA; n = 6). All horses were sedated with intramuscular (IM) xylazine (0.5 mg/kg). Anesthesia was induced with intravenous (IV) guaifenesin (100 mg/kg) and thiopental (5 mg/kg) and maintained with isoflurane in oxygen. Animals in groups with preemptive analgesia received IM morphine (0.2 mg/kg) and dipyrone (10 mg/kg) and IV flunixin meglumine (1.0 mg/kg) immediately before sedation. Recoveries from general anesthesia were rope-assisted. Recovery scores (from 8 [excellent recovery] to 70 [worst recovery]) and times were compared between groups, using a one-way analysis of variance followed by a Tukey's test (P < .05). Mean ± standard deviation (SD) and range recovery scores were 22 ± 14 (8–45), 9 ± 2 (8–12), 14 ± 5 (8–22), and 12 ± 1 (10–13) in groups GA, GAA, GC, and GCA, respectively. Mean ± SD times to stand in minutes were 21 ± 10, 18 ± 7, 33 ± 12, and 35 ± 21 in groups GA, GAA, GC and GCA, respectively. No statistically significant differences were found for any of the variables. Neither preoperative administration of analgesics, including morphine, nor castration interfered with the recovery qualities and times in horses undergoing general anesthesia. Preemptive morphine did not worsen anesthetic recovery quality in horses.     

乌龙茶生产高峰期调控技术

介绍乌龙茶生产高峰期的4种调控技术,包括优化种植品种法、遮阴覆盖法、叶面追肥法、修剪调控法。