Complete maps of IS1, IS2, IS3, IS4, IS5, IS30 and IS150 locations in Escherichia coli K12

Summary In this paper complete distribution maps are presented of the seven IS elements 1, 2, 3, 4, 5, 30 and 150. These maps were obtained during the construction of an almost complete restriction map of the Escherichia coli genome of K12 strain BHB2600. The positions of IS elements were correlated to this map. The distribution of integration sites of all IS types is nonrandom. Besides a large gap from 79 min to 96 min, there is a pronounced IS cluster at 6 min and another at 97 min, map locations that have low gene incidences on the classical map. One cluster coincides with a region of IS induced rearrangements. The IS distribution pattern was compared to patterns of strains W3110 and HB101.     

四川围栏养殖林麝采食植物种类调查

对四川都江堰人工养殖围栏内林麝采食的野生及栽种植物种类进行调查.结果表明,围栏内共有林麝采食植物64种,隶属于31科,多属于农田野草、野菜,少数是栽种的饲草、树木.分析了林麝采食利用植物的特点及这些植物作为饲料在生产中的潜在应用价值.     

高速逆流色谱法同时分离制备头花蓼中没食子酸和原儿茶酸

对蓼科蓼属头状蓼组植物头花蓼进行化学成分的研究。本研究建立了HPLC测定中药头花蓼水提喷雾干燥粉末中化学成分含量的方法,然后应用高速逆流色谱法对头花蓼水提喷雾干燥粉末的乙酸乙酯粗提物的化学成分进行了半制备性分离研究,通过对分离方法和溶剂系统的筛选,寻找到最佳的溶剂系统(正己烷∶乙酸乙酯∶甲醇∶水=1∶5∶1∶5),上相为固定相,转速840 r/min,流速2.0 mL/min,进样量756 mg,检测波长272 nm。结果显示,在该条件下经一步分离可同时得到质量为148.5 mg和9.2 mg的两种产物,纯度为99.8%和97.4%,经紫外、红外、质谱及核磁共振等方法进行结构分析,确定分别为没食子酸和原儿茶酸。     

Establishment, Growth kinetics, and Susceptibility to AcMNPV of Heat Tolerant Lepidop teran Cell Lines

Lepidopteran heat-tolerant(ht)cell lines have been obtained with sf-9,sf-21 and several Bombyx cells.They have a distinct karyotype,membrane lipid composition,morphology and growth kinetics from the parental cell lines.In this paper,we report the development of ht cell lines from other insect species and examination of their growth characteristics and virus susceptibility.Adaptation of cell lines sf-9,BTI-TN-5131-4(High5)and BTI-TN-MG1(MG 1)to 33℃ and 35℃ was carried out by shifting the culture temperature between 28℃ and higher temperatures by a gradual stepwise increase in temperature.The process of adaption to a higher culture temperature was accomplished over a period of 2 months.The cell lines with the temperature adaption were designated as sf9-ht33,sf9-ht35,High5-ht33,High5-ht35,MG1-ht33,MG1-ht35.These cell lines have been subcultured over 70 passages.Adaption to high temperatures was confirmed by a constant population doubling time with individual cell lines.The population doubling time of heat adapted cell lines were 1-4 h less than these of parental cell lines.Cell shapes did not show obvious change,however,the cell size of sf9-ht cells was enlarged and those of High5 and MG1 ht cells were reduced after heat adaption.When the cell lines were infected with Autographa californica nuclear polyhedrosis virus(AcMNPV)at 28℃,33℃,35℃ and 37℃,production of budded virus and occlusion bodies in each cell line was optimum at its own adapted temperature.     

LPS response and endotoxin tolerance in Flt-3L-induced bone marrow-derived dendritic cells

Fms-like tyrosine kinase-3 ligand (Flt-3L) stimulates the differentiation of bone marrow cells into dendritic cells (DCs) and was used as an adjuvant therapy in the experimental model of burn wound sepsis. In this study, we describe the phenotypical characteristics of an Flt-3L-dependent DC culture (FLDC) system following LPS stimulation, which induces an inflammatory response, and after a second LPS stimulation, which induces tolerance. Priming of FLDCs with LPS via TLR4 has been shown to induce the activation of all three mitogen-activated protein kinase (MAPK) families and enhance NF-κB complex translocation into the nucleus. Stimulated FLDCs express all maturation markers and exhibit an increase in IL-12p40 production and to a lesser extent, IL-10 production. In contrast, LPS stimulation of tolerized FLDCs was not associated with TLR4 up-regulation and led to MAPK inhibition. The decrease in p38 and JNK activation was correlated with an impairment of IL-12p40 production. Endotoxin tolerance in FLDCs was associated with enhanced ERK1/2 activation, an increase in MKP-1 phosphatase expression, a decrease in NF-κB translocation to the nucleus and an increase in IL-10 production. Overall, DCs generated from bone marrow with Flt-3 ligand have similar characteristics to DC subtypes found in the steady state in vivo, which can acquire endotoxin tolerance in some circumstances.     

中国东南沿海裸鞘花水母一新属及三新种记述

记述了采自中国东南沿海台湾海峡南部、福建南部东山湾和福建东部宁德三都湾裸鞘花水母1新属——拟长管水母属Dipurenella gen.nov.和3新种,即刺胞海帽水母Halitiara knides sp.nov.,东山拟长管水母Dipurenella dongshanensis sp.nov.和粗管外肋水母Ectopleura crassocanalis sp.nov.。详细描述其形态特征,并与近似种进行比较。模式标本保存于厦门大学海洋与环境学院。     

Chemistry and selection

Life is the product of chemistry, which obeys deterministic laws, and of natural selection, which operates on variants offered to it by chance, but may, in a number of cases, have been provided with a sufficiently extensive array of variants to be optimizing. Thus, the origin and evolution of life have been largely shaped by the contingency of environmental conditions. The possibility remaining open for consideration is that certain critical conditions are sufficiently reproducible for life to arise and even to evolve into conscious, intelligent beings elsewhere in the universe.     

Integrating ecological features of species in spatial pattern analysis of a plant community

Objective: This empirical study was designed to explore the role of ecological features of species in the spatial patterning of a grassland community. Location: Banks of the river Rhône in France. Material and Methods: First, we explored the spatial pattern of 29 species recorded in the community using spatial autocorrelation analysis of species cover values. Second, we then explored the relationship between the patterns found and a set of life attributes that characterized the ecological features of species for resource foraging or dispersion. Finally, we explored the spatial relationship of groups of species that shared the same ecological features using cross‐correlation analysis. Results: We found a significant relationship between the spatial pattern and life attributes of the species highlighting three groups of species: (1) species characterized as competitors, reproducing by runner clonal organs and forming large, dense patches; (2) species characterized as competitive‐rud‐erals, dispersing exclusively by seed production and forming small periodic patches; and (3) species classified as CSR, characterized by rosette morphology and short rhizomes as clonal organs without any significant spatial autocorrelation. Spatial segregation was found between group 1 and group 2 up to 14 m; no significant cross‐correlation between groups 1 and 3 between 0 and 3.5 m, and association between groups 2 and 3 up to 14 m. Conclusions: These results helped to understand how species attributes (relative to stature or dispersion abilities); external factors (such as disturbance) and biotic processes (competition) interplay in structuring the plant community under study in space.     

内蒙古多伦县土地沙漠化景观格局变化特征

利用景观分析软件Fragstats 3.3和内蒙古多伦县1960、1975、1987、1995、2000、2005年6期遥感影像解译结果,分析了1960—2005年间土地沙漠化景观格局变化.结果表明:1960—1995年间研究区土地沙漠化面积呈先增后减趋势,总沙漠化面积增加212.70km2,沙漠化斑块数先增多后减少,景观多样性和均匀性上升,轻度、中度、重度沙漠化斑块形状趋向简单;1995—2005年间研究区沙漠化斑块数大幅增加,景观多样性和均匀性下降,轻度、中度、重度沙漠化斑块形状趋向复杂;严重沙漠化斑块形状在1960年以后一直趋向复杂化.整个景观在研究期间表现为完整-破碎-完整-破碎的趋势,由轻度到严重沙漠化,其景观类型的破碎化程度逐渐降低.     

小毛茛(Ranunculus ternatus Thunb.)花粉流潜能初探

在自然居群中对小毛茛传粉机制与距离作了观测,并对开花后花粉萌发能力的变化作了研究,结果是：该种兼具虫媒或风媒传粉机制,以虫媒传粉为主;传粉距离多数局限于２ｍ以内,但不排除远距离传粉的可能性;体外萌发试验表明,该种花粉萌发率在开花第一天甚低,开花后２４ｈ达到最高值。作者推测,小毛茛花粉以近距离散布为主,但具有远距离传播的潜能。