黄河上游灌区稻田N2O排放特征

黄河上游灌区稻田高产区过量施肥现象十分突出,氮肥过量施用引起土壤氮素盈余,导致N₂O排放量增大,由此引起的温室效应引起广泛关注。采用静态箱-气相色谱法研究黄河上游灌区稻田不同施肥处理下N₂O排放特征。试验设置5个施肥处理,包括常规氮肥300 kg/hm²下单施尿素和有机肥配施2个处理,分别用N300和N300-OM代表;优化氮肥240 kg/hm²下单施尿素和有机肥配施2个处理,分别用N240和N240-OM代表;对照不施氮肥用N0代表。试验结果得出,灌区水稻生长季稻田土壤N₂O排放主要集中在水稻分蘖前及水稻生长的中后期,稻田氮肥施用、灌水及土壤温度的变化对N₂O排放通量影响较大,不同处理水稻各生育阶段N₂O累积排放量与稻田土壤耕层NO^-₃-N含量动态变化显著相关。稻田N₂O排放不是黄河上游灌区稻田氮素损失的主要途径,但灌区稻田N₂O排放的增温潜势较大;稻田氮肥过量施用会显著增加N₂O排放量,在相同氮素水平下,有机肥配施会显著增加稻田土壤N₂O的排放量(P＜0.01)。优化施氮能有效减少灌区稻田水稻生长季N₂O排放量。稻田不同处理的水稻整个生长季土壤N₂O排放总量为2.69-3.87 kg/hm²,肥料氮通过N₂O排放损失的百分率仅为0.43%-0.64%。在灌区习惯灌水和高氮肥300 kg/hm²时,N300-OM处理的稻田N₂O排放量达3.87 kg/hm²,在100 a时间尺度上的全球增温潜势(GWPs)为20.76×10⁷ kg CO₂/hm²;优化施氮240 kg/hm²水平下,N240和N240-OM处理的N₂O累计排放量较N300-OM处理,分别降低了1.18 kg/hm²和0.57 kg/hm²,在100 a尺度上每年由稻田N₂O排放引起的GWPs分别降低了6.33×10⁷ kg CO₂/hm²和3.06×10⁷ kg CO₂/hm²。     

Courtship in Drosophila quadrilineata with a unique male behavioral element, abdomen bending

This paper describes courtship of Drosophila quadrilineata of the immigrans group and reports a species-specific element, abdomen bending, that has not been described in Drosophila. The male bends his abdomen right and left as a display to the female. During courtship the male circles around the female, bends his abdomen, and taps her. The male licks the female ovipositor repeatedly, often after the females extrusion. Although the females ovipositor extrusion is thought to indicate rejection of a courting male in many species, the male of D. quadrilineata continues courtship. It is possible that the extrusion is a females mating signal to the courting male. The male of D. quadrilineata mounts the female in a rearward position and the genitalia of both sexes couple after mounting. This mounting position is shared by the species belonging to the immigrans group. We never observed behavior in which it appeared as if the male displayed the black stripes to the female. Males court one another and a courtship chain is frequently formed even in the absence of females. The males abdomen bending and the females extrusion followed by the males licking are discussed.     

Syntheses and characterizations of two lanthanide(III)-copper(II) coordination polymers constructed by pyridine-2,6-dicarboxylic acid

The hydrothermal reaction of La₂O₃ and Pr₂O₃ with pyridine-2,6-dicarboxylic acid (H₂pydc), CuO, and H₂O with a mole ratio of 1:2:4:300 resulted in the formation of two polymeric Cu(II)-Ln(III) complexes, [{Ln₄Cu₂(pydc)₈(H₂O)₈} · 18H₂O]_n (Ln = La (1); Pr (2)). 1 and 2 are isomorphous and crystallize in monoclinic space group C2/c. Complexes 1 and 2 have one-dimensional infinite chains with “∞” shape. The 1D chains are linked by the hydrogen bonds and π?π stacking interactions to form layer structures which are further linked by the hydrogen bonds and π?π stacking interactions to form the three-dimensional (3D) structures with nanoscale porosities. Temperature-dependent magnetic susceptibilities and the thermal stabilities of complexes 1 and 2 were studied.     

民族植物学定量研究中的取样方法

定量方法在民族植物学研究中越来越占有重要的地住,但民族植物学定量研究中有关取样方面还存在着一些不同的看法。笔者针对云南省金平苗族瑶族傣族自治县的拉祜族民间草医所使用的药用植物资源和草医对不同生境中药用植物的利用情况进行了取样,并以此对民族植物学中有关取样中存在的问题进行了讨论。结果表明不同生境中民族植物学的取样面积与植物生态学中的取样面积比较相近。所以在进行民族植物学野外取样时,司以针对具体的生境和植被特点来借用植物生态学中对该类生境或植被所采用的最小取样面积。     

巫山蓝家寨遗址家畜的动物骨骼

2012年巫山蓝家寨遗址考古发掘中,出土了春秋时期的马(Equus caballus)、黄牛(Bos taurus)、山羊(Capra hircus)、鸡(Gallus gallus domesticus)、狗(Canis familiaris)、猪(Sus domestica)6种家畜的骨骼。这是三峡地区唯一一个在先秦时期六畜兼备的古文化遗址。遗址中的马、牛,是三峡地区同类家畜中时代最早的发现资料。三峡地区早期历史时期,人类肉食资源以野生动物为主,家畜动物骨骼发现材料较少。蓝家寨遗址出现种类较多的家畜动物种类,为全面分析和认识三峡地区经济形态发展过程、古居民行为模式和区域文化等,提供了重要资料。遗址中在春秋时期出现的家畜马和黄牛,与该时期各种区域文化在三峡地区的碰撞、交流、融合有关。     

山东鲁中南地区周-汉代人骨研究

本文对 11例出土于山东省鲁中南地区保存较好的周 -汉代颅骨进行测量研究。在颅、面部测量特征的比较上 ,这批头骨与鲁北地区同时代头骨特征类似 ,都属于东亚蒙古人种类型。与周邻地区古代人群的聚类分析与主成分分析结果表明 ,鲁中南周 -汉代组人群与黄河流域古代类群的亲缘关系比与华南组的更接近 ,这组人群与西日本弥生人接近的程度明显大于与绳文人接近的程度。本研究支持在现代日本人的起源中有源自中国大陆特别是华北东部地区的因素。     

Mechanism of steroid action in inflammation: Inhibition of prostaglandin synthesis and release

Acute arthritis was induced by injection of cell-free extract of group A Streptococci into the knee joints of mature male rats. Slices of control and inflamed synovia were incubated for 30 to 240 minutes and the rate of prostaglandin E (PGE) released into the medium was measured by radioimmunoassay. PGE release from inflamed synovia was 5–8 fold higher than that in normal tissue. Incubation of inflamed synovia with corticosterone acetate, dexamethasone or prednisone (100 μg/ml) for one or four hours reduced PGE release by 33% and 55% respectively. Lower concentrations of corticosterone (10 – 30 μg/ml) were ineffective. Aldosterone and progesterone (100 μg/ml) had no effect on PGE release throughout the incubation period. Chloroquine (10 μg/ml) inhibited PGE release from inflamed synovia by 50%. Indomethacin (1 μg/ml) abolished PGE release by 90%. Corticosterone, dexamethasone and prednisone reduced PGE content of inflamed synovia by approximately 45% during a 4-h incubation period. Aldosterone and progesterone were ineffective, while indomethacin reduced PGE content by 70%. The suppressive action of corticosterone on PGE release was prevented by addition to the medium of arachidonic acid (2 μg/ml). By contrast, the inhibitory action of indomethacin was not affected by provision of exogenous substrate. We suggest that glucocorticosteroids reduce PGE release by limiting the availability of the substrate for prostaglandin biosynthesis, and this may well explain some of their anti-inflammatory properties.     

抗生素含量测定方法的分析概述

抗生素作为一种抗菌物质,在现代医疗中起着非常重要的作用。2015版中华人民共和国药典共收录抗生素药品363种,所介绍的抗生素含量测定方法有4种。根据抗生素测定方法的统计,在这363种抗生素中,有275种采用高效液相色谱法;有75种采用抗生素微生物检定法;有8 种采用紫外-可见分光光度法;只有5种采用了滴定法。以最新的2015版中华人民共和国药典为基础,对抗生素的测定方法进行了分析概述,期望能在环境抗生素残留量的测定方面提供可借鉴的内容。     

Assessing regional sustainable development through an integration of nonlinear principal component analysis and Gram Schmidt orthogonalization

The regional sustainable development level (SDL), sustainability of regional development (SRD) and system coordination (SC) make up the triangular truss of regional sustainable development assessment, but it is debated how should traditional practice best weight and calculate the whole sustainable development system level. The Bohai Rim, covering three provinces and two municipalities in China, lies in a region that is sensitive to profound conflict between socioeconomic development and environment pollution in the process of sustainable development. Considering the defects of traditional models and the multidimensionality of regional sustainability issues, we proposed an integrated model of nonlinear principal component analysis and Gram Schmidt orthogonalization and presented a novel regional sustainable development assessment method and framework from three perspectives for the society–economy–environment system of the Bohai Rim region. The results show that: (a) the integration of nonlinear principal component analysis and Gram Schmidt orthogonalization can well remedy the defects of traditional methods and provide a more objective conceptual framework; (b) the sustainability of regional development and system coordination models graphically demonstrate the essence and connotation of a dynamic sustainable development system; (c) the empirical study demonstrated that the Bohai Rim region has experienced a distinct development period in which the SRD experienced a steady decline and the SDL and SC generally increased; (d) the coordination ability can be improved by a decline in the environmental sustainability, which reveals the importance of environment subsystem optimization; and (e) the weight distribution of variables demonstrates that the most significant factors affecting sustainable development are the indicators from the dimensions of people's standard of living, economic structure and environmental pollution. This study enriches the sustainable development assessment theory and methodology, and lays the foundation for further sustainable development research in the Bohai Rim region.     

Ships in Distress,Environmental Threats to Coastal States,and Places of Refuge: New Directions for an Ancien Regime ?

Places of refuge for ships in distress is a topic before the International Maritime Organization as a result of several recent well-publicized refusals by maritime authorities of coastal states to allow such ships to enter sheltered waters within national jurisdiction. The traditional right of refuge of the crew, ship, and cargo is pitted against threat perceptions held by coastal states resulting in a "not in my backyard" syndrome. Instances of modern state practice seem to restrict the right of refuge to a purely humanitarian dimension. There is a need to reevaluate the right of refuge and to establish a system of places of refuge on the basis of regional cooperation to counter the potential threat of stricken ships that are unable to effect necessary repairs in sheltered areas within national jurisdiction.