Reproductive biology of the female Japanese mantis shrimp Oratosquilla oratoria (Stomatopoda) in relation to changes in the seasonal pattern of larval occurrence in Tokyo Bay, Japan

ABSTRACT:   The reproductive traits and the monthly larval abundance of the mantis shrimp Oratosquilla oratoria were investigated in Tokyo Bay, Japan, in 2002. The goal of the study was to elucidate the cause of changes in the monthly pattern of larval abundance from the 1980s to the 1990s as these changes relate to variation in the stock size of the adult shrimp. Oogenesis was divided into 10 stages by histological observation. The developmental stage of oocytes in an individual's ovary was synchronous, suggesting that almost all the oocytes in an ovary are spawned at the same time. The size at first maturity was estimated to be 7 ≤ body length ( BL ) < 8 cm. Fecundity was expressed as a function of BL , ranging from 19 300 eggs for 8 cm BL to 92 100 eggs for 14 cm BL . Small female shrimps (<10 cm BL ) spawned around August. Most large female shrimps (≥10 cm BL ) spawned around May, and some large female shrimps also spawned until September. Although most large female shrimps spawned in spring, the larval abundance was low before July and high from August onwards. The results suggest that a substantial decrease in the stock size of large individuals causes the low larval abundance before July.     

Modifying the response to defoliation during vegetative growth in CERES-Maize

CERES-Maize (Vl. 0) predicted no grain yield when 100% defoliation occurred during vegetative growth. This result conflicted with field observations where 100% defoliation early in the vegetative stage did not materially reduce grain yield. CERES-Maize was modified to realistically predict yields when defoliation greater than 50% occurred during vegetative growth by taking into account stem (stem proper and sheath) photosynthesis and translocation of dry matter from the stem to the developing leaves. With these modifications, predictions from CERES-Maize were in good agreement with field measurements when defoliation occurred both early and later in the vegetative stage. This modified version of CERES-Maize can be the basis of a decision support system for defoliating pests of corn where yields can be evaluated under different management strategies and climate scenarios.     

Characterization of and radioimmunoassay for canine thyroglobulin

Canine thyroglobulin (cTg) has been isolated and purified. It has similar electrophoretic patterns as Tg from other mammalian species. The main fraction had a MW of 660,000, whereas also fractions of a MW of approximately 1,300,000 (dimer) and 330,000 (subunit) were present. The iodine content was 0.8 to 1.0 % (w/w). cTg did not cross-react with antibodies against human Tg to a degree that would allow the use of a radioimmunoassay for human Tg for the determination of cTg in serum or plasma. Therefore a polyclonal antiserum was raised against cTg and a homologous radioimmunoassay was developed, which was sensitive (0.4 μg/l) and specific (cross-reactivity in cTg assay of human Tg, goat Tg, T₄, T₃, and DIT < 0.01 %).

Plasma Tg levels in normal dogs of both sexes and aged 3–15 years amounted to 192 ± 73 μg/l (mean ± SD, n=30). There was no relation between plasma Tg and T₄ levels.     

山洪对房屋的破坏及防患

山洪对房屋的破坏随着生态环境的恶化而加剧,其损失又随人民生活水平的提高而增加。防患房屋遭受山洪破坏刻不容缓。本文客观地总结了山洪破坏房屋具有的区域性、多样性、毁灭性特征,通过分析房屋遭受山洪破坏的沉痼陋习,初步揭示了山洪惩罚人为性大失误的沉痛教训,进而提出防患山洪破坏房屋要非工程措施与工程措施相结合,运用社会、经济、法律的手段,加以减灾引导,加强建房管理,采取开撇水沟、挖水平槽、刨鱼鳞坑、砌护坡墙、打挡水桩等直接有效的工程措施,加速隐患补救,实现减灾目的。     

木瓜剖分原理研究及新机型设计

针对我国目前对木瓜剖半设备研究较少,剖切方式不合理,切割效果差等问题,设计开发了新型木瓜剖半机。该机切割方式选用滑切切割的方式,由运料系统、切割系统、出料系统组成,设计合理,结构简单。为此,计算了滑切角、切割角等主要切割参数,并给出了新型剖半机的主要技术参数。试验表明:该机切割效果好,能够有效提高生产效率。     

2009年4月全国饲料生产形势分析

1全国总体概况 4月份，国内畜禽产品消费增加，禽类产品价格有所回升，饲料产量继续增长，水产饲料增长幅度尤为明显。根据对全国29个省（自治区、直辖市）167家饲料企业的调查显示，其总产量为270．4万t，同比上涨5．1％，环比上涨12．2％（表1）。