Science Letters:Differentiation of xanthomonads causing the bacterial leaf spot of poinsettia in China from the pathotype strain of Xanthomonas axonopodis pv. Poinsettiicola

In October 2003, a new bacterial disease with symptoms similar to those caused by Xanthomonas axonopodis pv.poinsettiicola was observed on poinsettia leaves at a flower nursery in Zhejiang Province of China. Three Xanthomonas strains were isolated from infected plants and classified as X. axonopodis. They were differentiated from the pathotype strain LMG849 of X. axonopodis pv. poinsettiicola causing bacterial leaf spot of poinsettia by comparison of pathogenicity, substrate utilization and BOX-PCR genomic fingerprints.     

烟草野火病病原细菌的鉴定

烟草野火病是一种在烟草上普遍发生的毁灭性细菌病害,由烟草野火病菌引起,近年来,云南省主要产烟区连年发生,危害严重,论述了烟草野火病菌的鉴定方法。     

不同时期可溶性蛋白质含量与猕猴桃抗溃疡病之间的关系

实验以安徽省岳西县感、抗性不同的猕猴桃品种为研究对象,分别在2005-2006年的不同季节对它们一年生枝条韧皮部可溶性蛋白质含量与抗病性的表现进行相关性研究.结果如下:2005年10月和2006年1月测得可溶性蛋白质含量与相对感病指数之间存在着线性相关性,相关系数为-0.969,-0.887,线性回归方程分别为Y=8.712-50.718 X,Y=34.590-226.357X,且达到显著水平.     

浅谈矮生一品红的栽培

通过对一品红进行扦插、矮化处理、花期调控、病虫害防治等方面的试验,从而摸索出一品红在山区露地栽培的一些关键技术     

一品红天然色素提取工艺的探讨

本文对从“一品红”中提取红色天然食用色素进行了研究和试验 ,探索了影响提取率的各种因素 ,提出了最佳工艺条件     

甘蔗糖蜜发酵产黄原胶优良菌株的选育

黄原胶是由野油菜黄单胞菌发酵生产的重要的商业微生物多糖产品,实验通过微波诱变处理保藏菌株,筛选到一株能以甘蔗糖蜜为碳源发酵生产黄原胶的优良正突变株X12,实验结果表明:在初步确定的实验条件下,该菌株发酵生产黄原胶的产量达22.14 g/L,是未诱变菌株20183的1.53倍,传代实验表明,突变菌株X12的黄原胶产量及性状无大变化,遗传性状稳定。     

Microbial control of diamondback moth, Plutella xylostella L.(Lepidoptera:Yponomeutidae) using bacteria (Xenorhabdus nematophila) and its metabolites from the entomopathogenic nematode Steinernema carpocapsae

Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.     

Microbial control of diamondback moth, Plutella xylostella L.(Lepidoptera: Yponomeutidae) using bacteria (Xenorhabdus nematophila) and its metabolites from the entomopathogenic nematode Steinernema carpocapsae

Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.     

Microbial control of diamondback moth,Plutella xylostella L. (Lepidoptera: Yponomeutidae) using bacteria (Xenorhabdus nematophila) and its metabolites from the entomopathogenic nematode Steinernema carpocapsae

Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.     

福建沿海地区电子信息产业空间结构优化研究

电子信息产业是福建省发展最快的三大支柱产业之一,主要分布于福建沿海地区.文章通过区位商方法分析了福建沿海地区电子信息产业空间结构特征、存在的问题,并在问题原因剖析的基础上提出福建沿海地区电子信息产业空间结构优化思路.认为：福州应重点发展计算机和显示器产业,厦门重点发展光电、通讯和动漫产业,漳州重点发展智能小家电,泉州重点发展微波通讯和光伏产业,莆田和宁德重点生产小型消费类电子产品.     

华中神农架气候梯度上的维管束植物物种多样性

Ｆｒｏｍａｇｌｏｂａｌｖｉｅｗｐｏｉｎｔ ,ｔｈｅｄｉｓｔｒｉｂｕｔｉｏｎｏｆｂｉｏｄｉ ｖｅｒｓｉｔｙｃａｎｂｅａｓｓｏｃｉａｔｅｄｗｉｔｈｃｌｉｍａｔｅ[1] .Ａｍａｊｏｒｉｔｙｏｆｐａｔｔｅｒｎｓｏｆｓｐｅｃｉｅｓｄｉｖｅｒｓｉｔｙｃａｎａｌｓｏｂｅｅｘｐｌａｉｎｅｄｉｎｔｅｒｍｓｏｆｃｌｉｍａｔｉｃｇｒａｄｉｅｎｔｓ[2 5] .Ｗｉｔｈｉｎａｇｉｖｅｎｍｏｕｎ ｔａｉｎｒａｎｇｅ ,ｃｌｉｍａｔｅｍａｙａｆｆｅｃｔｔｈｅｄｉｓｔｒｉｂｕｔｉｏｎａｎｄａｂｕｎｄａｎｃｅｏｆｐｌａｎｔｓｐｅｃｉｅｓｓｉ…     

四种植物提取液抑菌作用的分析

选择三种野生有毒植物白屈菜、胡桃楸和细叶杜香及常见植物蒲公英,研究了它们对三种黄单胞菌属植物病原细菌的抑菌作用．提取四种植物有效成分的提取液,采用96孔板法测定四种植物的最低抑菌浓度（MIC）,并用带药平板法检验．试验结果表明,白屈菜、胡桃楸和蒲公英对三种植物病原细菌都有不同程度的抑菌活性．白屈菜（茎叶）和蒲公英抑菌活性较强,对三种植物病原细菌的最低抑菌浓度分别为0．1g／ml、0．1g/ml、0．05g/ml,白屈菜（根）和胡桃楸抑菌活性稍差,细叶杜香提取液未检测到抑菌能力．     

Pathogenicity of bacterium, Xenorhabdus nematophila isolated from entomopathogenic nematode （Steinernema carpocapsae） and its secretion against Galleria mellonella larvae

INTRODUCTION Entomopathogenic nematodes of the generaSteinernema and Heterorhabditis have been used tocontrol a wide range of agriculturally important insectpests (Kaya and Gaugler, 1993). The mechanism bywhich these nematodes are able to infect and repro-duce in the insect host involves a mutual relationshipbetween the nematode and the symbiotic bacteria,Xenorhabdus spp. and Photorhabdus spp. (Akhurstand Dunphy, 1993; Forst and Nealson, 1996). Poinarand Thomas (1966) established tha…     

A Womanist Experience of Caring: Understanding the Pedagogy of Exemplary Black Women Teachers

In recent years, a compelling discussion in education has centered on caring. In this paper, I contribute to this dialogue by suggesting that there is a particular form of caring exhibited in the pedagogy of exemplary black women teachers. It is the purpose of this paper to illuminate central aspects of their pedagogy as facets of womanism, an epistemological perspective based on the collective experiences of black women. As educators who exhibit womanist caring, such teachers demonstrate the following three characteristics: an embrace of the maternal, political clarity, and an ethic of risk. In describing each characteristic, I provide both contemporary and historical evidence to demonstrate that womanism is part of a long-standing tradition among African-American women teachers. I conclude the paper by suggesting that we can better inform pre- and in-service educators about the types of teachers that our students need from an understanding of how and why exemplary teachers exhibit their womanist caring.     

超白玻璃唇砖更换工艺以及材质的研究

伴随光伏新能源产业的发展,光伏超白压延玻璃生产效率和相关技术得到进一步提升。唇砖是太阳能超白压延玻璃生产中的关键设备之一,其材质的选择以及质量和安装工艺直接决定了太阳能超白压延玻璃的良品率以及使用周期等。本文介绍了多种超白压延玻璃唇砖材质,并根据实际生产情况选出了最佳材质选择,同时对相关技术要求做了详细的介绍。本文根据业内已有成就,结合自身特点以及经验,完善并优化了唇砖更换工艺程序,最大限度延长了唇砖使用寿命,提高了超白压延玻璃的综合良品率。     

青木香(Aristolochia debillis Sieb.et Zucc.)的抗菌活性

通过琼脂平板扩散试验和双倍稀释试验,对青木香(Aristolochia debillis Sieb.et Zucc.)的石油醚提取物、乙酸乙酯提取物和甲醇提取物进行了抗细菌和抗真菌作用的研究,在三种提取物中,只有甲醇提取物对试验的所有革兰氏阳性和革兰氏阴性细菌都表现出显著的抗菌作用,乙酸乙酯提取物只对测试的部分细菌显示出抗菌作用,石油醚提取物不具有抗菌活性.甲醇提取物比乙酸乙酯提取物具有更强的抗菌作用和更广的抗菌谱.三种提取物对所有试验的真菌都没有显示出抗菌作用.     

关于BCI一代数的诣零理想

本文讨论BCI一代数X的N_k(x)、N(x)的性质。进一步给出它们的剩余刻划。     

“数 ＋量 ＋动”结构的名词性及其生成机制

借鉴构式语法理论对“数＋量＋动”结构进行分析。在典型构式“数＋量＋名”的基础上形成的“数＋量＋x”构式,其构式义有三项内容,即1、“数＋量”对“X”进行计量;2、构式整体上是名词性的。且这种名词性不随其内部成分的变化而变化;3、X位置上的词语在该构式的层面上表现为名词性。而在语义层面上这个位置上的词语可以是名词,也可以是动词、形容词等。因此,“数＋量＋动”作为非典型构式,是典型构式“数＋量＋名”的继承和引申,其“动词”及整个结构的名词性是“数＋量＋X”这一构式赋予的,是一定认知机制制导下构式压制的结果。     

Detection of bacterial DNA by PCR and reverse hybridization in the 16s rRNA gene

The clinical diagnosis of sepsis is difficult, particularly in neonates. To devise a rapid and reliable method for identifing bacteria in blood and cerebrospinal fluid (CSF), we developed a pair of primers according to the gene encoding 16 s rRNA, found in all bacteria. DNA fragments from different bacterial species and from clinical samples were detected with polymerase chain reaction (PCR), and with reverse hybridization using a universal bacterial probe, a gram-positive probe and a gram-negative probe. Our results showed that a 371 bp DNA fragment was amplified from 20 different bacterial species. No signal was observed when human DNA and viruses were used as templates. The sensitivity could be improved to 10⁻¹² g. All 26 culture-positive clinical samples (22 blood samples and 4 CSF samples), were positive with PCR. The gram-negative and gram-positive probe hybridized to clinical samples and to known bacterial controls, as predicted by Gram’s stain characteristics. Our results suggest that the method of PCR and reverse hybridization is rapid, sensitive and specific in detecting bacterial infections. This finding may be significant in the clinical diagnosis of sepsis in neonates. Project (396457) supported by the Zhejiang Provincal Natural Science Foundation.     

三种草坪草的核型研究

通过对禾本科的黑麦草、燕麦草和高羊茅的根尖细胞的染色体数目及核型的研究,结果表明:黑麦草是二倍体,2N=2X=42,染色体核型公式为:2N=2X=18m(2SAT) 18sm 6st,核型类别为2C;燕麦草是二倍体2N=2X=28,染色体核型公式为:2N=2X=26m 2sm,核型类别为2B;高羊茅是二倍体2N=2X=36,染色体核型公式为:2N=2X=20m 16sm,核型类别为2B。