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971.
Isabel C.F.R. Ferreira Lillian Barros Maria Elisa Soares Maria Lourdes Bastos José Alberto Pereira 《Food chemistry》2007,103(1):188-195
Olive trees (Olea europaea L. Cv. Cobrançosa) from the northeast of Portugal were sprayed with three different copper formulations [bordeaux mixture (copper sulphate + calcium hydroxide − 20% Cu), copper hydroxide (40% Cu) and copper oxychloride (50% Cu)] to control olive fungal diseases. The residues of copper in olive leaves, harvested at different times, were evaluated by atomic absorption spectrometry. At all the collection times, treated olive leaves had significantly higher copper contents, compared to the control. The different copper amounts in pesticide formulations lowered the leaves contents in total phenols and hence their antioxidant properties. Olive leaves sprayed with copper oxychloride possessed the highest copper levels and the lowest content in phenols, which influenced its antioxidant activity (higher EC50 values for reducing power, scavenging effect on DPPH radicals and inhibition of erythrocyte hemolysis). Leaves without copper residues proved to be a good natural source of antioxidants, giving values comparable to the reference compounds. 相似文献
972.
Christ Mary Anne G.; Lahey Benjamin B.; Frick Paul J.; Russo Mary F.; McBurnett Keith; Loeber Rolf; Stouthamer-Loeber Magda; Green Stephanie 《Canadian Metallurgical Quarterly》1990,58(6):840
Early motherhood (r?=?.33) with the number of Diagnostic and Statistical Manual of Mental Disorders (DSM-III) symptoms of conduct disorder in a sample of 253 boys (aged 6–13 yrs) who had been referred to outpatient clinics. The following models were compared using path analysis: (1) Teenage motherhood, parental antisocial personality, and socioeconomic status (SES) each contribute uniquely to the prediction of childhood conduct problems; (2) teenage motherhood mediates the association of SES and parental antisocial personality with child conduct problems; and (3) teenage motherhood is spuriously related with child conduct problems because of common associations with SES and parental antisocial personality. Model (3) best fit the data. Similar results were obtained whether maternal age at the birth of the firstborn child or the proband child was used to define maternal age and when teenage motherhood was defined as giving birth at 相似文献
973.
Two new ternary line codes are presented. Although the two codes are similar, they differ with respect to error propagation properties and power spectral densities. The codes are relatively simple, yet they satisfy tight channel input restrictions, making them suitable for use in practical baseband communications systems.<> 相似文献
974.
Anna Gliszczyńska-Świgło Alina Kałużewicz Katarzyna Lemańska Mikołaj Knaflewski Bożena Tyrakowska 《Food chemistry》2007,100(1):241-245
The effect of solar radiation on the quercetin and kaempferol contents in the inflorescence of three broccoli cultivars (‘Lord’, ‘Marathon’ and ‘Fiesta’) was investigated from 1999 to 2001. Great differences in the contents of both flavonols, dependent on growing time and cultivar, were found. Quercetin and kaempferol contents varied from 14.3 to 81.0 mg kg−1 f.w. and from 35.9 to 213 mg kg−1 f.w., respectively. Inflorescences of the cultivar ‘Lord’ were characterised by the highest mean content of quercetin and those of cultivar ‘Fiesta’ of kaempferol. The contents of both flavonols were highly positively correlated with total solar radiation in the period from planting to the harvest of broccoli inflorescences. 相似文献
975.
Prof J. L. Encarnaco 《Computer Graphics Forum》1986,5(4):385-385
976.
L. A. Ferreira E. V. Diatzikis P. J. Moreira J. L. Santos F. Farahi 《Optical Fiber Technology》2000,6(4):1132
The interrogation of fiber Bragg grating sensors with multimode laser diodes is theoretically and experimentally analyzed using two different approaches: serrodyne and dithering techniques. It is also demonstrated that by using several laser modes it is possible to enhance the measurement range without compromising sensitivity. 相似文献
977.
Previous work by the authors has shown that the effects of calcium aluminate cement (CAC) and hydratable alumina (HA) can modify the magnesia hydration behavior in aqueous suspensions. As a consequence of these studies, the present paper highlights how varying the content of these binders can affect magnesia hydration in refractory castables using pH, apparent volumetric expansion, mechanical strength and porosity measurements and hydration–dehydration tests. Furthermore, as mechanical strength, porosity and refractoriness also play an important role in these materials, binder-free, magnesia-free and magnesia-and-binder-free samples were also tested as references. It was found that the deleterious effects of magnesia hydration can be greatly minimized by the binder and its selection content. 相似文献
978.
Antonio Luiz P. S. Campos Adaildo Gomes d'Assunção Marcos A. Barbosa de Melo 《Journal of Infrared, Millimeter and Terahertz Waves》2000,21(3):461-475
A full wave analysis is developed for frequency selective surfaces composed of rectangular patches mounted on a dielectric anisotropic substrate and covered with a uniaxial anisotropic superstrate. The moment method is used in combination with the spectral domain immittance approach to determine the FSS structure reflection and transmission coefficients. 相似文献
979.
B Fortu?o L Torres E Simal A Seoane JA Uriel C Santacruz 《Canadian Metallurgical Quarterly》1997,15(10):536-539
BACKGROUND: This review summarizes the different species of dermatophytes isolates in our laboratory between 1991 and 1995. We describe the clinical forms and establish the distribution over this period of time. METHODS: Retrospective survey of samples from outpatients of the Dermatology Service in Miguel Servet Hospital where mycologic cultures are required. The extraction of samples is made by scrapes with a carpet or scalpel and they are cultured on Saboureaud agar with chloramphenicol and dermatophytes agar for 3 weeks. All plates were incubated at 28 degrees C. The identification of isolated strains is made by means of morphologic and physiologic criteria; the doubtful strains were identified in national referral center of Majadahonda CNMVISS. RESULTS: 4004 samples were analyzed from 3934 patients and 543 strains of dermatophytes were isolated. The frequencies were as follow: Microsporum canis (44%), Trichophyton mentagrophytes (31.4%), Trichophyton rubrum (18.6%), Epidermophyton floccosum (2.6%), Microsporum gypseum (1.4%), Trichophyton tonsurans (0.7%), Trichophyton verrucosum (0.7%), Trichophyton violaceum (0.2%) y Microsporum audouinii (0.2%). The most frequently observed dermatophytoses were Tinea corporis (54.8%), followed by Tinea unguium (12.6%), Tinea capitis (12.5%), Tinea pedis (8.3%), Tinea manuum (6.3%), Tinea cruris (4.7%) and Tinea barbae (0.7%). CONCLUSIONS: The zoophylic species are the most prevalent in our area and we have observed a raise of Microsporum canis in recent years. It is important to perform mycologic survey in every suspected lesion in older to determinate the true incidence of human dermatophytoses. 相似文献
980.