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441.
Saúl Otero Encarnación Núñez-Olivera Javier Martínez-Abaigar Rafael Tomás Satu Huttunen 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2335-2344
We analyzed bulk UV absorbance of methanolic extracts and levels of five UV-absorbing compounds (hydroxycinnamic acid derivatives) in 135 herbarium samples of the liverwort Jungermannia exsertifolia subsp. cordifolia from northern Europe. Samples had been collected in 1850–2006 (96% in June–August). Both UV absorbance and compound levels were correlated positively with collection year. p-Coumaroylmalic acid (C1) was the only compound showing a significant (and negative) correlation with stratospheric ozone and UV irradiance in the period that real data of these variables existed. Stratospheric ozone reconstruction (1850–2006) based on C1 showed higher values in June than in July and August, which coincides with the normal monthly variation of ozone. Combining all the data, there was no long-term temporal trend from 1850 to 2006. Reconstructed UV showed higher values in June–July than in August, but again no temporal trend was detected in 1918–2006 using the joint data. This agrees with previous UV reconstructions. 相似文献
442.
József Gábor Joó Artúr Beke Csaba Papp Ernő Tóth-Pál Ákos Csaba Zsanett Szigeti Zoltán Papp 《黑龙江环境通报》2007,27(10):912-921
Objective This study was conducted to evaluate the major demographic details, diagnostical and clinical features, as well as the risk of recurrence of cases with the major types of neural tube defects (NTD). We also examined the efficiency of ultrasonography based on autopsy examinations during 26 years. Methods The investigations were made into the sample of 743 NTD diagnosed between 1 January 1976 and 31 December 2002. A computerized database was used to sum up the available information about the individual cases; in addition to surveying the couples' major demographic details, we also had the opportunity to collect detailed information about the history, diagnostics (ultrasound) and outcome of the pregnancies as well as the results of the autopsies during the investigation. Results In the 743 cases of NTD, maternal and paternal median ages turned out to be 23.7 years (±5.22 years) and 28.7 years (±5.81 years), respectively. The male:female ratio was 0.78. Comparable samples of anencephaly and spina bifida allowed for the conclusion that a positive genetic history was equally often found while a positive obstetrical history was almost twice as common in anencephaly. The sensitivity of the maternal serum-alpha fetoprotein (AFP) screening test is the highest in anencephaly and lowest in encephalocele. While the majority of cases of anencephaly were diagnosed before the 24th gestational week, examples of diagnosing spina bifida and encephalocele at a later time could also be found. Among the associated malformations other than those of the central nervous system special mentioning should be made of fetal pyelectasia, cleft palate as well as diaphragmatic herniation. No pathological karyotypes were found in association with encephalocele or spina bifida, but anencephaly was accompanied with trisomy 21 and trisomy 18 in one case each. Anencephaly was found to have the highest risk of recurrence in both nervous system malformations and malformations other than those of the nervous system. Sonography proved to be the most reliable method in cases of enecephalocele. Conclusion The respective median values of maternal and paternal age show that aetas has no role in the occurrence of NTDs. NTDs are more common among girls. Positive genetic, obstetrical and medical findings are of great importance in the incidence of NTDs. Although reliable to only a limited extent, maternal serum-AFP tests are considered to be useful and necessary in screening NTDs, while sonography is the gold standard method in recognizing these frequent malformations. The knowledge of the eventual associated malformations is mainly important in certain cases of spina bifida, which may also yield a good post-natal prognosis. Our data obtained from the sample of 26 years also confirm that the periconceptional administration of folic acid reduces the incidence and risk of recurrence of NTDs. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Assis Rhayane Alves Rezende Wadson Rodrigues dos Santos Cirley Gomes Araújo Benvindo-Souza Marcelino Amorim Nathan Pereira Lima Borges Rinneu Elias Franco-Belussi Lilian De Oliveira Classius de Souza Santos Lia Raquel 《Environmental science and pollution research international》2021,28(43):60741-60752
Environmental Science and Pollution Research - The sensitivity of anuran to the effects of habitat destruction and contamination has led to a preoccupying global decline in their populations.... 相似文献
445.
Zamora-Briseño Jesús Alejandro Améndola-Pimenta Monica Ortega-Rosas Daniel Antonio Pereira-Santana Alejandro Hernández-Velázquez Ioreni Margarita González-Penagos Carlos Eduardo Pérez-Vega Juan Antonio del Río-García Marcela Árcega-Cabrera Flor Rodríguez-Canul Rossanna 《Environmental science and pollution research international》2021,28(26):34309-34327
Environmental Science and Pollution Research - Crude oil is one of the most widespread pollutants released into the marine environment, and native species have provided useful information about the... 相似文献
446.
Karen Hardy Anita Radini Stephen Buckley Ruth Blasco Les Copeland Francesc Burjachs Josep Girbal Riker Yll Eudald Carbonell Jose María Bermúdez de Castro 《Die Naturwissenschaften》2017,104(1-2):2
Sima del Elefante, Atapuerca, Spain contains one of the earliest hominin fragments yet known in Europe, dating to 1.2 Ma. Dental calculus from a hominin molar was removed, degraded and analysed to recover entrapped remains. Evidence for plant use at this time is very limited and this study has revealed the earliest direct evidence for foods consumed in the genus Homo. This comprises starchy carbohydrates from two plants, including a species of grass from the Triticeae or Bromideae tribe, meat and plant fibres. All food was eaten raw, and there is no evidence for processing of the starch granules which are intact and undamaged. Additional biographical detail includes fragments of non-edible wood found adjacent to an interproximal groove suggesting oral hygiene activities, while plant fibres may be linked to raw material processing. Environmental evidence comprises spores, insect fragments and conifer pollen grains which are consistent with a forested environment. 相似文献
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449.
J.V. López Alvarez M. Aguilar Larrucea P. Arraiza Bermúdez B. León Chicote 《Waste management (New York, N.Y.)》2009,29(5):1514-1519
The presence of paper in municipal solid waste (MSW) interferes with the efficiency of composting plants. The compost feedstock to these plants is between 12% and 27% paper on a dry weight basis, with an initial C:N ratio ranging from 32:1 to 57:1. Tests of the last aerobic biodegradability (LAB) of the type of paper present in paper and cardboard packaging were carried out, following UNE-EN 14046 standards. The results obtained, measured through the quantity of CO2 generated over 45 days, compared with the maximum that could be produced (ThCO2), showed that the presence of paper retards, to a great degree, the biodegradation of organic material in general. Specifically, the presence of papers with a degradation D (%) >60% at 45 days (white (W) and recycled paper (R)) could be allowed, but always in proportions that did not exceed 27% in dry weight. These results can be achieved with an industrial level process, pre-treated by trituration. 相似文献
450.