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81.
Aerosol samples were continuously collected at Rishiri Island, Japan and concentrations of trace metals and water-soluble ionic constituents in the aerosol samples were measured in this study. Trace metal concentrations were analyzed by using inductively coupled plasma mass spectrometry equipped with a laser ablation sample introduction (LA/ICP-MS), which is a rapid and simultaneous method for multi-element analysis. The average concentrations of trace metals and water-soluble ionic constituents in TSP at Rishiri Island from March 2001 to October 2003 were: Al: 251 ± 371 (n= 359), Ti: 27 ± 38 (n= 342), V: 1.3 ± 1.6 (n= 327), Cr: 2.0 ± 2.2 (n= 202), Mn: 8.6 ± 12.0 (n= 353), Fe: 356 ± 645 (n= 349), Co: 0.18 ± 0.25 (n= 250), Ni: 1.9 ± 3.4 (n= 232), Cu: 7.4 ± 10.2 (n= 123), Zn: 16 ± 20 (n= 242), As: 1.2 ± 2.1 (n= 312), Se: 0.49 ± 0.65 (n= 133), Cd: 0.19 ± 0.33 (n= 285), Sb: 0.46 ± 0.62 (n= 265), Pb: 16 ± 30 (n= 314), Na+: 1153 ± 1384 (n= 306), NH4 +: 247 ± 257 (n= 254), K+: 74 ± 63 (n= 284), Ca2+: 144 ± 174 (n= 294), Mg2+: 150 ± 161 (n= 293), Cl?: 2703 ± 3151 (n= 180), NO3 ?: 339 ± 415 (n= 332), SO4 2?: 1648 ± 1398 (n= 362) (unit: ng m?3). The obtained trace metal concentration levels in the aerosol were 1/10–1/70 of those obtained at Beijing, China and 1/2–1/40 of those obtained at Tokyo, Japan. The correlation between Al, Ti, Mn, and Fe, which were derived mainly from soil dust, was high at Rishiri Island. High-concentration events (when the measured value exceeds the average +3σ for the entire observation period) for each chemical constituent were observed several times per year, although the chemical concentration levels in TSP at Rishiri Island were almost constant throughout the year. The high-concentration phenomenon, which occurred in only 2% of the measurement days, raised the average concentration of the atmospheric chemical constituents at Rishiri Island by about 10%. The average value of the Pb/Zn ratio at Rishiri Island during the entire period was 1.8 ± 2.9, which is higher than 1. This suggests that the atmosphere at Rishiri Island has constantly been receiving contaminants from the Asian Continent. We conclude that the chemical constituents in the aerosol at Rishiri Island have been regularly transported from a wide area across the Asian Continent. 相似文献
82.
Mario A. Pagnotta Alfredo Impiglia Oronzo A. Tanzarella Miloudi M. Nachit Enrico Porceddu 《Genetic Resources and Crop Evolution》2005,51(8):863-869
The durum wheat landrace Haurani (Triticum durum Desf.) is grown under contrasting climatic regions of Syria from Deir Ezzor, in the North-East (230 m altitude, 150 mm mean annual rainfall), to Qunaytra, in the South-West (1060 m altitude, 825 mm mean annual rainfall). In order to assess the genetic variation between and within Haurani populations, samples from eight provinces of Syria (Daraa, Damascus, Qunaytra, Deir Ezzor, Hassakeh, Aleppo, Homs and Hama) were analysed by RFLPs and seed storage proteins of glutenin subunits as markers. The analyses showed the presence of genetic polymorphisms in all populations with the highest values in those from Homs and Hassakeh. Moreover, the results point out differences in genetic distances between populations; some populations were further apart, such as Damascus and Aleppo, whereas others were closer to each other, for instance Homs and Hama. Cluster analysis identified two distinct groups of populations, characterized by geographical proximity, with similar rainfall and altitude. It is suggested that the similarity of landraces at locations close to each other might be the result of more frequent seed exchanges between farmers or of gene flow due to 5% estimated outcross rate of Haurani. 相似文献
83.
João S. Dias 《Genetic Resources and Crop Evolution》1995,42(4):363-369
Nuclear RFLPs were used to study the genetic relationships of 2 Portuguese coles, tronchuda cabbage and Galega kale, and 13
otherBrassica oleracea cultivars and 4 nine-chromosome wild brassicas. Cluster and principal coordinates analysis were conducted using RFLP data
from 60 probe-enzyme combinations, detecting 277 polymorphic restriction fragments. The results showed that the accessions
clustered in five groups: one with all theB. oleracea cultivars except kailan, and the four others isolated with kailan, wildB. oleracea, B. insularis andB. cretica, andB. montana, respectively. Kailan was separated from the other accessions ofB. oleracea cultivars and genetically close to the wildB. oleracea, that was clearly separated from the other nine-chromosome wild brassicas. In theB. oleracea cultivars 3 groupings were clearly individualized: i) including broccolis and cauliflower; ii) with a misture of kales and
cabbages originally from Central-North Europe; iii) formed by Portuguese coles. These preliminary results suggest the existence
of three major regions of domestication of B. oleracea in Europe: Italy, Central-North Europe and Portugal. Kailan or chinese
kale seems to have evolved separately from the otherB. oleracea cultivars in Eastern Asia. 相似文献
84.
Bastos De Maria CA Moreira Santos MC José De Lima Dias U Marana M 《Journal of agricultural and food chemistry》2000,48(9):3935-3938
The effect of heated quercetin (400 mg/kg of oil) or 5-caffeoylquinic acid (5-CQA) and the presence of ferric ion (2.2 mg/kg of oil) on the stability of soya oil oxidized in an oxidative stability index (OSI) instrument was investigated. After heating the phenolic at 100 degrees C or 150 degrees C, the OSI values of treated oils were not significantly (p < 0.001) different, whereas, at 200 degrees C, the values decreased significantly with addition of quercetin, but not with 5-CQA. However, the antioxidative activity of quercetin remained significantly greater than that of 5-CQA. The antioxidative potency of quercetin was reduced significantly by addition of ferric palmitate (FP), but that of 5-CQA was not. Reaction between the ortho-dihydroxy groups of the quercetin and ferric ion may reduce the number of hydroxyls available to react with free radicals. Chelating action of 5-CQA might be provided by ortho-dihydroxy grouping of the quinic acid moiety. 相似文献
85.
Mario Cipone DVM Marco Pietra DVM Gulatiero Gandini DVM Andrea Borai DVM Carlo Guglielmini DVM Massimiliano Venturoli DVM 《Veterinary radiology & ultrasound》1997,38(3):200-206
A pulsed wave-Doppler ultrasonographic evaluation of common carotid arterial blood flow was carried out on 63 healthy Italian Saddlebred horses. Vessel diameter and tracing morphology were evaluated were evaluated and blood flow parameters (systolic, diastolic and mean velocity, acceleration and deceleration of the systolic wave, cartid pulse volume) were calculated and correlated with class variables (sex, age and body weight). On the basis of the presence of an incisure in the ascending branch of the systolic curve, subjects were divided in two groups: one with a bifid systolic curve and the other with a monophasic aspect. Correlations between: 1) diameter of the vessel and body weight and 2) carotid pulse volume and flow velocity (systolic, diastolic and mean) were found. A greater systolic pulse volume was found in male subjects, in subjects with greater body weight and in those which had a monophasic systolic wave. 相似文献
86.
Mario Businelli Francesco Tafuri Luciano Scarponi Cesare Marucchini 《Pest management science》1975,6(5):475-480
Analytical methods are described for the determination of residues of benfluralin in soil and carrots. All plots treated with 1.3 or 1.9 kg benfluralin/ha produced average carrot yields significantly higher than untreated plots. Degradation of benfluralin in soil was very slow during the winter. As the temperature rose, the rate of benfluralin decline was accelerated; 324 days after incorporation, benfluralin residues were reduced to about 11 and 14% of the applied dose. The average total residues of benfluralin found in whole carrots were 210 ± 18 and 240 ± 47 ng/g following doses of 1.3 and 1.9 kg a.i./ha respectively. The peel of carrots contained 92% of the total residue, and there seemed to be little translocation of the compound through the plant tissues. 相似文献
87.
Por S. Mello Dias P. Pinto Silva V. J. M. Campos A. M. Orsi M. C. Oliveira Dayoub R. M. Define 《Anatomia, histologia, embryologia》1983,12(4):347-352
In the literature reviewed, there are certain differences of opinion with regard to the formation and tributareis to the ureter. Therefore, dissection of 40 fowls injected with neoprene latex, k neoprene latex and celobar (radiopaque mass) and vinyl acetate casts through the ureter and blood vessels revealed the formation and disposition of the tributaries to the ureter, and its origin and number of collectors. The results were described in relation to the renal lobes. 相似文献
88.
Mario Businelli Francesco Tafuri Cesare Marucchini Luciano Scarponi 《Pest management science》1975,6(1):69-73
A gas-liquid chromatographic method using electron-capture detection is described for the determination of perfluidone residues in rice grains and husks. The procedure consists of extraction, purification on an anion-exchange resin, methylation and further clean-up (if necessary) by adsorption on “Florisil”. The recoveries from fortified rice grains and husks were respectively 73.5–98% and 77–104% in the range 0.01–0.50 mg/kg. Sensitivity permits detection of perfluidone at 0.005 mg/kg level. 相似文献
89.
ABSTRACT In previous studies, liquid swine manure (LSM) was sometimes shown to reduce Verticillium wilt of potato caused by Verticillium dahliae. We also observed that microsclerotia of this fungus died within 1 day, or between 3 and 6 weeks, after addition of LSM to some acid soils and within 1 week in some alkaline soils. In this study, we demonstrated that a volatile fatty acid (VFA) mixture with an identical concentration of VFAs as that found in an effective LSM reduced germination in an acid soil (pH 5.1) to the same extent as the LSM after 1 day of exposure. Germination was reduced by 45, 75, and 90% in the 10, 20, and 40% ([wt/wt] soil moisture) treatments, respectively, with the latter being equivalent to an application of 80 hl/ha. Addition to this acid soil of 19 LSMs (30% [wt/wt] soil moisture) collected from different producers resulted in complete kill of microsclerotia with 12 manures. Effective manures had a total concentration of nonionized forms of VFAs in soil solution of 2.7 mM or higher. In some acid soils (pH 5.8), addition of LSM (40% [wt/wt] soil moisture) did not kill microsclerotia until 3 to 6 weeks later. Here, a reduction in viability of microsclerotia was attributed to the accumulation of 0.06 mM nitrous acid in the soil solution at 4 weeks. When an LSM was added (40% [wt/wt] soil moisture) to an alkaline soil (pH 7.9) where VFAs are not toxic, microsclerotia germination was reduced by 80% after 1 week. Here the pH increased to 8.9 and the concentration of ammonia reached 30 mM in the soil solution. An ammonium chloride solution having an equivalent concentration of ammonium as the manure was shown to have the same spectrum of toxicity as the manure in assays ranging from pH 7 to 9, both in solutions and above the solutions. At pH 9, the concentration of ammonia reached 18 mM and 100% mortality of microsclerotia occurred. Thus, in acid soils, LSM can kill microsclerotia of V. dahliae by VFA and/or nitrous acid toxicity and in alkaline soils by ammonia toxicity. In order to take advantage of these mechanisms for disease reduction, the manure chemical composition, rate of addition, and soil characteristics need to be determined for each instance of use. 相似文献
90.
Mihalis Cutrubinis Henry Delincée Mario Stahl Olaf R?der Hans Jürgen Schaller 《Gesunde Pflanzen》2005,224(4):129-136
Saatgut und Getreide kann mit niederenergetischen Elektronen (<300 kev) oder=" hochenergetischen=" elektronen=" (1–10 mev)=" wirksam=" behandelt=" werden,=" um=" mikroorganismen=" und=" insekten=" abzutöten.=" in=" dieser=" vorläufigen=" studie=" wurde=" mais=" mit=" niederenergetischen=" (125 kev)=" und=" hochenergetischen=" elektronen=" (10 mev)=" behandelt.=" um=" diese=" elektronenbehandlung=" nachzuweisen,=" wurden=" verschiedene=" verfahren=" eingesetzt:=" photostimulierte=" lumineszenz=" (psl),=" thermolumineszenz=" (tl)=" und=" dna-kometentest.=" für=" diese=" drei=" nachweismethoden=" existieren=" bereits=" europäische=" normen=" und=" sie=" sind=" als=">300 kev)>Allgemeine Codex Methoden zum Nachweis bestrahlter Lebensmittel etabliert. Die Ergebnisse zeigen, dass PSL und TL geeignete Verfahren sind, um sowohl eine Behandlung von Mais mit niederenergetischen als auch mit hochenergetischen Elektronen zu erkennen. Der DNA-Kometentest erwies sich als weniger geeignet: die Behandlung mit niederenergetischen Elektronen konnte—wie erwartet—nicht nachgewiesen werden. Die Behandlung mit hochenergetischen Elektronen konnte bei einer Maissorte erkannt werden, jedoch nicht bei einer anderen Sorte. 相似文献