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1.
Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra. showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Heli-coverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that 相似文献
2.
Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate,
linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited
stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either
enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph
could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde
combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These
results suggested that some volatiles should modify sex pheromone caused behavior and that some of them couldpossibly be used
as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field.
Project supported by Knowledge Innovation Program from Chinese Academy of Sciences (CAS) (No. KSCX2-02-5-2) and Shanghai Commission
of Science and Technology (Nos. 023912004 and 01JC14051), China 相似文献
3.
Xuan Cai Rong-zhang Mai Jing-jing Zou Hong-yan Zhang Xiang-ling Zeng Ri-ru Zheng Cai-yun Wang 《Journal of Zhejiang University. Science. B》2014,15(7):638-648
Objective: Aroma is the core factor in aromatherapy. Sensory evaluation of aromas differed among three sweet osmanthus (Osmanthus fragrans) cultivar groups. The purpose of this study was to investigate the aroma-active compounds responsible for these differences. Methods: Gas chromatography-olfactometry (GC-O) and GC-mass spectrometry (GC-MS) were used to analyze the aroma-active compounds and volatiles of creamy-white (’Houban Yingui’, HBYG), yellow (’Liuye Jingui’, LYJG), and orange (’Gecheng Dangui’, GCDG) cultivars. Results: Seventeen aroma-active compounds were detected among 54 volatiles. trans-β-Ocimene, trans-β-ionone, and linalool, which were major volatiles, were identified as aroma-active, while cis-3-hexenyl butanoate, γ-terpinene, and hexyl butanoate were also aroma-active compounds, although their contents were low. Analysis of the odors was based on the sum of the modified frequency (MF) values of aroma-active compounds in different odor groups. HBYG contained more herb odors, contributed by cis-β-ocimene and trans-β-ocimene, while LYJG had more woody/violet/fruity odors released by trans-β-ionone, α-ionone, and hexyl butanoate. In GCDG, the more floral odors were the result of cis-linalool oxide, trans-linalool oxide, and linalool. Conclusions: Aroma-active compounds were not necessarily only the major volatiles: some volatiles with low content also contributed to aroma. The aroma differences among the three cultivars resulted from variation in the content of different odor groups and in the intensities of aroma-active compounds. 相似文献
4.
林伟忠 《广东轻工职业技术学院学报》2006,5(1):22-23
在常温下对羟乙基氧苯乙酮与苯甲醛合成了对羟乙基氧苯乙酮缩苯甲醛。在同样的条件甚至更高温度下，对羟基苯乙酮等类似结构的酮不与苯甲醛发生缩合反应。 相似文献
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以南京地区610名公务员为研究对象,使用Sonost 2000超声骨密度仪测试受试者跟骨骨质状态的T值、Z值、骨强度指数、骨折风险等指标。结果显示:男、女性同性别40～50岁年龄组的骨密度状态指标中的T值、骨强度指数和骨折风险,与30～40岁年龄组均有显著差异(P<0.05或P<0.01),男性50～60岁年龄组的Z值的绝对值明显小于其他年龄组(P<0.01);同年龄组男、女性在各指标上均无显著性差异(P>0.05),男性各项骨密度指标值均优于同龄组女性。研究男、女性公务员骨密度的衰减明显期,可为其提高骨密度或防止骨密度衰减提供适宜的干预时机。 相似文献
7.
Oliván G 《Child abuse & neglect》2003,27(1):103-108
OBJECTIVE: To assess the catch-up growth of long-term physically neglected and emotionally abused preschool male children who have entered foster residential care and remained 1 year after initial placement. METHOD: Longitudinal study over a 7-year period (1994-2001). So that a child was eligible for the study, three selection criteria were included: (1) aged between 24 and 48 months at the time of entry into residential facility, (2) having suffered both long-term (more than 6 months) physically neglected and emotionally abused, and (3) having stayed in foster care for 1 year after initial placement. Weight, height, and head circumference were established upon entry and re-assessed 1 year after initial placement, calculating the annual growth velocity. Results were compared with normal regional longitudinal standards of reference (Z score). Student's t test was used to assess statistically significant differences. RESULTS: During the study period, 87 children aged between 24 and 48 months (54 male/33 female) were admitted to residential facility after having suffered both long-term physical neglect and emotional abuse. Nevertheless, only 20 children (23% of the total admissions) met the third selection criteria (having remained 1 year after initial placement). Of these children, all were males and at placement they were between the ages of 30 and 42 months, with an average age of 36 months (1.9 SD). At placement, the analyzed parameters were below the normal standards, showing a statistically significant difference for height (Z score = -1.29; p = .008) and weight (Z score = -.75; p = .038). The annual growth velocity for all parameters was above the normal standards showing a statistically significant difference for height (Z score = +1.43; p = .009). One year after initial placement, the significant differences for height (Z score = -.68; p = .102) and weight (Z score = -.31; p = .435) with respect to the normal standards disappeared, though still remained below, showing a significant catch-up growth for height (improvement height Z = +.61 SD). CONCLUSIONS: At placement, the both long-term physically neglected and emotionally abused preschool age male children showed a mild form of chronic malnutrition with growth failure. Growth failure was reversible after the first year of stay, which demonstrates that this delay in growth was secondary to nutritional and psychosocial factors. Placement in foster residential care was beneficial for the catch-up growth of these patients. 相似文献
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A novel UV-curable prepolymer neopentyl glycol diglycidyl ether diacrylate(NPGGEA)was synthesized by using neopentyl glycol diglycidyl ether(NPGGE)and acrylic acid(AA)as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were taken as follows: The concentration of N,N-dimethylbenzylamine, 0.80% of reactants; the concentration of p-hydroxyanisole, 0.3% of reactants; the reaction temperature, 90-110℃; the molar ratio of NPGGE to AA, 1:2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-cured initiator was added to the synthesized NPGGEA to prepare a kind of UV-cured coating. Mechanical properties of the UV-cured films were determined, giving 28.75 MPa of tensile strength, 923.82 MPa of Young‘s modulus and 5.51% of elongation at tear. 相似文献
9.
郑哲民 《商丘师范学院学报》2012,(6):1-18
系统地记录中国蚱总科中羊角蚱属、柯蚱属及台蚱属的种类,以检索表形式进行分类研究,共记述羊角蚱属33种,柯蚱属29种,台蚱属55种,其中包括7新种,即广东羊角蚱Criotettix guangdongensis sp.nov.、广州柯蚱Coptotettix guangzhouensis sp.nov.、尖峰柯蚱Coptotettix jianfengensis sp.nov.、直缘柯蚱Coptotettix orthomarginis sp.nov.、海南台蚱Formosatettix hainanensis sp.nov.、波股台蚱Formosatettix undulatifemura sp.nov.及黑胫台蚱Formosatettix nigritibia sp.nov..模式标本保存于陕西师范大学动物研究所. 相似文献
10.
《Learning and individual differences》2007,17(3):260-268
It is often questioned as to why fewer women enter science. This study assesses whether a cognitive style characterized by systemizing being at a higher level than empathizing (S > E) is better than sex in predicating entry into the physical sciences compared to humanities. 415 students in both types of discipline (203 males, 212 females) were given questionnaire and performance measures of systemizing and empathy. 59.1% of the science students were male and 70.1% of the humanities students were female. There were significant sex differences on the Empathy Quotient (EQ) (females on average scoring higher) and on the Systemizing Quotient (SQ) (males on average scoring higher), confirming earlier studies. Scientists also scored higher on the SQ, and scored lower on the EQ, compared to those in the humanities. Thus, independent of sex, SQ was a significant predictor of entry into the physical sciences. Results from questionnaire data and performance data indicate an S > E profile for physical science students as a group, and an E > S profile for humanities students as a group, regardless of sex. We interpret this as evidence that whilst on average males show stronger systemizing and females show stronger empathizing, individuals with a strong systemizing drive are more likely to enter the physical sciences, irrespective of their sex. 相似文献
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以红霉素A为起始原料,经红霉素腙法合成红霉素胺,再与制备的侧链溴代乙醛缩二乙醇进行缩合生成地红霉素,同时对产物结构进行了表征．该工艺合成地红零素的总收率为19．2％． 相似文献
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刘小平 《阜阳师范学院学报(社会科学版)》2001,(5):21-23
本文认为妇女为争取更大的生存空间和思想自由的努力,并非必须从过分专注地言说“性”开始,女性主义及其文学对现存的性观念的反叛在消解和对抗男性中心主义文化的同时,也有意地忽略了文明的一些基本规范和根本精神。在市场经济社会里,这种言说和反叛还会被消费主义所利用,为“欲望的狂欢”提供舞台,这样最终导致了女性主义及其文学在目标上的窘困和意义上的迷失。 相似文献
13.
Alain Savoie 《The International Journal of Art & Design Education》2009,28(1):25-36
Fine arts teachers' concerns about male underachievement in a Quebec coeducational high school, and a related survey showing boys' negative perceptions of fine arts motivated this interdisciplinary literature review. Referring to biology and cognitive science, the article explores concepts of sex‐related cognitive traits to help in designing sex‐adapted approaches to individual learning in art education. The nature‐nurture controversy still surrounds sex‐based cognitive differences studies, though science agrees that natural and socio‐cultural factors are somehow closely interwoven in the complex gender identity construction process. Sex‐related biological predispositions influencing cognition are proposed notably in ‘instrumentality‐expressiveness' and ‘empathising‐systemising (E‐S)’ theories. The article suggests that in the context of art education, these sex‐related cognitive models deserve study, because they could initiate sex‐adapted teaching strategies with the necessary flexibility and wider scope to overcome gender‐stereotyped biases and stimulate boys' interest in the arts. This suggested approach should not be confused with stereotype‐based pedagogy, which merely strengthens learned gender characteristics, producing or maintaining academic underachievement. 相似文献
14.
《诗经》中的鱼与性爱 总被引：2，自引：0，他引：2
金荣权 《南阳师范学院学报》2004,3(10):54-56
鱼是人类所钟爱的动物，在漫长的中国化史中，鱼被赋予了丰富的化内涵，形成了别具一格的“鱼”化。因为鱼是生殖力很强的一种生物，又因鱼可以充饥，正如婚姻可以满足人的情欲需要，所以鱼在《诗经》中就与性爱联系起来了。以鱼隐喻男女性爱与性要求，以网鱼比得妻，以网破喻失妻，以钓鱼喻求爱。可以说《诗经》中凡是涉及“鱼”的作品大部分都与性爱有关。 相似文献
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采用顶空固相微萃取( HS-SPME)技术提取干、鲜杏花的挥发性成分,经气相色谱-质谱测定,比较分析干、鲜杏花的香气成分变化.分析结果表明：鲜杏花中鉴定出2种挥发组分,占总挥发组分相对百分含量的95.09%,苯甲醛占总挥发组分的93.55%;干杏花中鉴定出20种挥发组分,占总挥发组分相对百分含量的92.17%,其中苯甲醛占总挥发组分的25.07%.可见干、鲜杏花挥发油化学成分种类和含量均有明显的差别. 相似文献
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文章以贵州五个少数民族男性为对象,进行男性人口性行为现状进行研究。通过分层整群抽样法抽取苗族、侗族、布依族、仡佬族和水族男性人口,认为少数民族地区学生性观念相对保守;青少年性与生殖健康教育仍然是空白;而已婚人群性与生殖健康水平也有待提高。 相似文献
17.
尹伟 《广东教育学院学报》2005,25(3):61-66
稀土元素铕与双Schiff碱N，N’-二(亚水杨基)-1，4-二氨基丁烷(L1)、N，N-二(亚水杨基)-1，5-二氨基戊烷(L3)和双Schiff碱还原产物N，N'-二(水杨基)-1，4-二氨基丁烷(L2)形成配合物的荧光是以配体发光为主．当双Schiff碱和TTA共存于同一配合物时，配体的协同发光效应使得络合物的发光表现为强的Eu^3 特征光谱，其最大荧光量子产率为0．21．络合物的能量传递过程主要是由配体的n→π^*跃迁吸收辐射能并直接向中心离子转递能量，中心离子被激发至激发态^5LJ(J=10，8，7，5)，然后无辐射弛豫至^5D0，发生^5D0→^7FJ(J=0，1，2，3，4)的跃迁，发射出Eu^3 特征光谱．络合物Eu(Lx)(TTA)(NO3)3(x=1，3)分子发光器件是由络合物中配体的苯环和噻吩环——天线的底座，S、O和N原子——接受光信号的原子天线和中心Eu^3 离子——原子信号发射器所组成． 相似文献
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N. G. McCrum 《牛津教育评论》2013,39(4):369-397
Abstract The academic efficiency and social justice of entry procedures at Oxford and Cambridge Universities are examined over the past quarter of a century. For each major subject the mean A‐level scores of males and females entering from state and independent schools are compared with mean final examination scores in the major subjects. In any comparison of state and independent cohorts of the same gender, within the bounds of normal statistical fluctuation, the difference in A‐level score is a good predictor of the difference in finals score. For example, when between state men and independent men the difference in A‐level score is zero, the difference between mean finals score is zero also. The origin of female under‐achievement is examined. In most subjects there is pronounced gender inequality due to the following chain of circumstances: (1) to break‐even in finals women require at entry better grades at Advanced Level than men; (2) women used to have much the better A‐levels and so, in finals a quarter of a century ago, they matched and even — in some subjects — surpassed the men; (3) the A‐levels of women entering Oxford and Cambridge Universities fell off during the 1970s; (4) today female A‐level scores are slightly worse than male A‐level scores, and so female finals scores are much worse, in most subjects, than male finals scores. The concept of an ideal subject is defined; this is a subject in which zero difference in A‐level score between male and female yields zero difference in finals score. Law at Cambridge and chemistry at Oxford are ideal subjects. Ideal subjects are rare at Oxbridge: most subjects exhibit a significant male lead in finals when male and female have equal A‐level scores. The most non‐ideal subject at Oxford is mathematics, in which zero difference in A‐level score between males and females yields a male lead in finals score of 13%: at Oxford the other non‐ideal subjects are physics (male lead at equal A‐levels 11%), philosophy, politics and economics (9%), history (8%), modem languages (8%) and English (5%). An ideal subject is a paradigm which requires even‐handedness between male and female cohorts in the following parameters: (1) efficiency of course selection from school; (2) efficiency of teaching; (3) efficiency of finals assessment; (4) latent ability. A pronounced relative decline in the A‐level scores of girls educated in state maintained schools entering English and Welsh universities occurred in the 1970s; it is attributed to the reform of the state school system, particularly the growth in mixed‐sex comprehensive schools and the decline in the number of female single‐sex grammar schools. A peculiar aspect of the admissions filters at both Oxford and Cambridge ensures that state‐school educated men gaining entry do so with A‐level scores markedly superior to those of the other three cohorts. 相似文献
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Associations are usually assumed to have only a predictive directionality, from Event 1 (E1) to Event 2 (E2). However, this unidirectionality, if it really exists, could be specific to the use of conditioned responses as the index of learning (i.e., conditioned responses are ordinarily elicited only when a conditioned stimulus [CS] predicts an unconditioned stimulus [US]). The present research used neutral stimuli, devoid of CS-US directionality, in order to test whether the underlying associative mechanism was unidirectional in nature. We used colors and figures as E1s and E2s. In Experiment 1, human subjects saw the events in the E1→E2 direction during training. In theconsistent group, the same E1 was always followed by the same E2; in theinconsistent group, E1s and E2s were paired randomly. In a subsequent test phase, we presented an E2 and subjects had to judge whether a particular E1 was associated with it. The judgments of the consistent group were higher than those of the inconsistent group, thereby suggesting that the association that the consistent subjects had learned was bidirectional. Experiments 2 and 3 confirmed the results of Experiment 1 while controlling for some alternative interpretations based on the representation-mediated formation of associations. 相似文献