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251.
Hiroe Yasui Sadao Wakamura Norio Arakaki Mitsunobu Kishita Yasutsune Sadoyama 《Chemoecology》2003,13(2):75-80
Summary. Ether extract of the abdominal gland of female black
chafers Holotrichia loochooana loochooana (Sawada) (Coleoptera:
Scarabaeidae) induced a series of pre-mating behaviors that included
short-distance orientation, mounting and abdominal bending toward
females in the laboratory. When the extract was chromatographed on a
silica gel column, the activity was eluted with 50% ether in hexane and
ether fractions. GC-MS analyses revealed that both the active fractions
contained anthranilic acid (2-aminobenzoic acid) as a major compound.
When partitioned to basic, acidic and amphoteric fractions, pheromonal
activity was observed with the latter two fractions and anthranilic acid
was detected in these fractions by HPLC analyses. The amount of
anthranilic acid in the female extract was estimated to be ca. 1.3
μg/female. Authentic anthranilic acid induced pre-mating behavior in
males of at levels equal to that elicited by the compound in the
extract. It also attracted male beetles to the traps in the field.
Received 29 October 2002; accepted 9 January 2003.
R1D="
Correspondence to:Hiroe Yasui, e-mail:yasui@affrc.go.jp 相似文献
252.
An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 atcoastal region, Cape D'Aguilar, in Hong Kong. The trace element composition of aerosol particles(TSP and PM10)were measured and analyzed by using the Instrumental Neutron Activation Analysis (INAA) and Inductive CouplePlasma-Mass Spectrometry(ICP-MS) techniques. The results showed that the polluted elements such as: V, Zn,As, Pb, Cd, Sb, I, Se, Bi, with high enrichment factor( E. F) values, are derived from anthropogenic sources ,while Sc, Al, Fe, Mn, Sm, La, Sr are less than 10 in E. F, these elements are related the crust and soil. Theconcentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the Vor noncrustal V(V* ) present summer high and winter low, this phenomenon might be explained by local or regionaloil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn* /V* and Bi/Al indicate that both TSPand PM10 of La/Sm ratios are mainly related to soil and dust, Mn*/V* are probably represent fossil combustion andBi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimaxrotation factor analysis for trace elements was performed. By means of the absolute principal component analysis(APCA) and multiple regression, the contribution of trace elements to possible sources and overall means of traceelements were estimated. The results showed that the present station is impacted by the anthropogenic species,although the quantities are different during the summertime and wintertime. 相似文献
253.
U.C. Kulshrestha L.A.K. Reddy J. Satyanarayana Monika J. Kulshrestha 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):5123-5127
Real-time simultaneous studies on chemical characteristics of rainwater and PM10 aerosols were carried out to understand the scavenging of major chemical components in Indian region. The concentrations of Ca2+, NH4+, SO42− and NO3− were observed to be lower in the aerosol samples collected during rain as compared to before and after rain events. The most significant reduction was noticed for Ca2+ (74%) during rain which showed highest scavenging ratio (SR) and indicated that below-cloud scavenging is an effective removal process for Ca2+ in Indian region. Among non-sea salt components, Ca2+ had highest SR at Hyderabad indicating typical characteristics of crustal influence as abundance of calcium carbonate in soil dust has been reported in India. However, the levels of these major chemical components gradually got build-up in due course of time. After rain events, the levels of SO42− aerosols were noticed to be substantially higher (more than double) within 24 h. In general, scavenging ratios for all components (except Ca2+, NH4+ and K+) were higher over BOB as compared to Hyderabad. The maximum fall in aerosol levels (BR minus AR) was observed during continuous and low intensity rain events that did not allow building up of aerosol concentrations. 相似文献
254.
四种不同植物湿地对不同C/N比生活污水的净化效果与季节动态 总被引:2,自引:0,他引:2
进水浓度、C/N比、植物种类是影响垂直流型人工湿地对生活污水净化效果的重要因素.本文主要研究了菖蒲(Acorus calamus)、香蒲(Typha orientalis)、千屈菜(Lythrum salicaria)和水葱(Scirpus Validus)等4种植物湿地在不同碳添加及C/N比处理条件下对模拟生活污水的净化效果和季节动态.结果表明,4种湿地植物在不同C/N比(2.5∶1、5∶1和10∶1)进水条件下均能正常生长.在一个生长季内4种湿地植物对主要污染物的平均去除效率为:COD 63.41%~78.02%,TN 33.19%~52.86%,TP 52.64%~73.16%.当C/N为5∶1时,香蒲湿地的COD和TP去除效果最佳,而当C/N为2.5∶1时,菖蒲湿地的TN去除率最高.夏末秋初(7—9月)人工湿地的净化效果较好,而冬季(11月—翌年1月)去除效果明显下降.总体而言,合理地调控进水浓度、C/N比,选择最佳的湿地植物,可显著提高垂直流型人工湿地对生活污水的净化效果. 相似文献
255.
IntroductionThehealthofcoastalenvironmenthasbeendrawingthepeople′sattentionsallovertheworld.Thebudgetsofnutrientsinthisareaareoneofthemainfocuses.Althoughnitrogenistheprimarylimitingnutrientformarinephytoplanktononaglobalbasis,exceptionsareoftenseenandparticularkindsofnutrientlimitationseemtobesituationspecificinmostcases.Inrecentyears,phosphorushasbeenfrequentlyreportedtobethelimitingnutrientforphytoplanktonproductivityincoastalwaterswithhighinputfromlandrunoff(Bonin,1989;Mahoney,1989;Heis… 相似文献
256.
Municipal solid waste(MSW) incineration has become an important anthropogenic source of heavy metals(HMs) to the environment. However, assessing the impact of MSW incineration on HMs in the environment, especially soils, can be a challenging task because of various HM sources. To investigate the effect of MSW incineration on HMs in soils, soil samples collected at different distances from four MSW incinerators in Shanghai, China were analyzed for their contents of eight HMs(antimony, cadmium, chromium, copper,lead, mercury, nickel, and zinc) and lead(Pb) isotope ratios. Source identification and apportionment of HMs were accomplished using principal component analysis and Pb isotope analysis. Results indicated that the relatively high contents of cadmium, lead,antimony, and zinc in the soils at 250 m and 750–1250 m away from the MSW incinerators were related to MSW incineration, while the elevated contents of the other four HMs were associated with other anthropogenic activities. Based on Pb isotope analysis, the contribution ratio of MSW incineration(which had been operated for more than 14 years)to the accumulation of Pb in soil was approximately 10% on average, which was lower than coal combustion only. Incinerator emissions of Pb could have a measurable effect on the soil contamination within a limited area(≤1500 m). 相似文献
257.
尼洋河流域水化学特征及其控制因素 总被引:21,自引:12,他引:9
为研究尼洋河流域水化学特征及其控制因素,2014年先后采集河水7组,井水13组,泉水10组,共计30组水样.综合运用数理统计、Piper三线图、Gibbs模型和离子比等方法,分析了尼洋河流域河水、泉水和井水的水文地球化学特征,并探讨了尼洋河流域的水化学演化规律.结果表明,河水、井水及泉水中阳离子均以Ca~(2+)、Mg~(2+)为主,占阳离子总量的84%以上;阴离子以HCO_3~-和SO_4~(2-)为主,占阴离子总量的97%以上;TDS介于79.11~290.48 mg·L~(-1)之间,平均值为165.21 mg·L~(-1),矿化度较低;水化学类型以HCO_3·SO_4(SO_4·HCO_3)-Ca·Mg(Mg·Ca)型水为主;水化学样品均分布在Gibbs模型左中部,说明该流域水化学离子组成受岩石风化作用控制;主成分分析及相关分析表明,尼洋河流域水化学组分受硅酸盐岩的溶解控制,碳酸盐岩的溶解也起到非常重要的作用. 相似文献
258.
The natural birth prevalence of Down's syndrome for England and Wales in 1974–1987 (i.e., the birth prevalence in the absence of prenatal diagnosis and the induced abortion of affected pregnancies) was estimated by applying the maternal age-specific birth prevalence derived from epidemiological studies to the number of births in single-year age groups tabulated by the Office of Population Censuses and Surveys (OPCS). On average, the natural birth prevalence was 12.6 per 10 000 births and increased slightly from 12.2 to 13.2 per 10 000 births over the 14-year period. Using data on induced abortions carried out on account of Down's syndrome reported to OPCS under the statutory abortion notification scheme, 14 per cent of affected births were avoided by the induced abortion of affected pregnancies, so that the actual birth prevalence of Down's syndrome was estimated at 10.8 per 10000 births. Using data on Down's syndrome births reported to OPCS under the voluntary congenital malformation notification scheme, the prevalence was 7.2 per 10000 births, so only 67 per cent of the estimated number of affected births were, in fact, notified to the scheme. 相似文献
259.
Ji Shulan Liu Zhipei Liu Zhipeng Ren Haiyan 《Frontiers of Environmental Science & Engineering in China》2007,1(3):325-328
A bacterial strain, ZY3, growing on sex steroid hormones as the sole source of carbon and energy was isolated from the sewage
treatment plant of a prophylactic steroids factory. ZY3 degrades the 3-methoxy-17β-hydroxy-1,3,5(10),8(9)-δ-4-estren (MHE).
This strain was preliminarily identified as Raoultella sp. ZY3 according to its morphology and its 16S rRNA gene sequence. During the experimental period (72 h), the optimum temperature,
pH and 3-MHE concentration for the degradation of hydride by the strain ZY3 were 35°C, 10 and 10 mg/L, respectively. The degradation
rate of the sex steroid hormones increased to 87% and 85% after the addition of maltose and peptone, respectively.
Translated from China Environmental Science, 2005, 25(5): 585–588 [译自: 中国环境科学] 相似文献
260.
Mikhail Goltsman Elena P. Kruchenkova Sergei Sergeev Paul J. Johnson David W. Macdonald 《Behavioral ecology and sociobiology》2005,59(2):198-206
Since the Pleistocene, Arctic foxes, Alopex lagopus, on Mednyi Island in the North Pacific have been isolated in a small area with rich food resources and no other terrestrial carnivores. This situation provides an unusually simple system within which the effect of food dispersion on demography and social organisation was examined. We studied the composition, location and dispersal of 67 Arctic fox groups and mapped their major food resources (seabird colonies) during 1994–2000 on Mednyi. We compared our observations with the predictions of models of sex-ratio determination. Our observations are most consistent with the predictions of Julliard's (2000) model, where mothers are expected to produce more offspring of the most dispersing sex in low-quality habitats, and more offspring of the most philopatric sex in high-quality habitats. The polygynous foxes on Mednyi Island lived where the principal food resources were patchily distributed (present on 11% of the shoreline), and cub survival to dispersal age or reproductive adult was higher in rich (25/45) than in poor (24/79) home ranges. Furthermore, dispersal was strongly sex-biased: most females (60%) remained on their natal ranges, whereas very few males (9%) did so. Significantly more female than male cubs (54 compared with 24) emerged from dens in resource rich ranges, whereas the sex ratio on poor ranges was approximately equal (51 females and 56 males). While our observations are also to some extent consistent with the local resource enhancement (LRE) hypothesis (which predicts a bias towards the sex most likely to cooperate with parents), this does not account for the observed spatial variability. 相似文献