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41.
The increase in the use of satellite‐derived precipitation products generated by different methods and algorithms emphasizes the need for a deeper analysis of their quality and accuracy. Using the contingency table method, we evaluated the accuracy of versions 6 and 7 of the Tropical Rainfall Measuring Mission Precipitation (TRMM) 3B42 product in southern Brazil by comparing daily precipitation over 13 years (V6 was tested for historical context). The interpolated data from 25 rain gauges were compared with both versions of TRMM. The V7 product tended to produce a slight increase in PC (proportion correct). V7 also showed a slight increase in the correlation coefficient (CC) and a significant increase in the H (hit rate) and CSI (critical success) indexes. However, the upgraded version shows an undesirable increase in the false alarm ratio. When the rainfall volumes were compared, V6 clearly underestimated the total rainfall over the entire period, but the V7 product slightly overestimated the cumulative volume (11%) which still represented a more reliable estimate than from V6. Furthermore, the main improvement in V7 was a large increase in the quantitative recognition of extreme precipitation events: V6 detected only 1% of the daily rainfalls above 60 mm, whereas V7 detected 57% of the events.  相似文献   
42.
This study is part of the BioMadrid Project, a bio-monitoring study designed to assess pollutants in the environment surrounding children born in the Madrid region. Our aim in this report is to evaluate the association between prenatal lead exposure and fetal development using three biological samples (maternal and paternal blood lead at around 34 weeks of gestation as well as cord blood lead levels), three biomarkers of effect in cord blood peripheral lymphocytes (micronucleus in binucleated cells, nucleoplasmic bridges, and nuclear buds), and different anthropometrical characteristics at birth. Maternal and cord blood lead were not associated with newborn measurements or genotoxicity biomarkers. In contrast, increases in father blood lead were coupled with lower weight (mean difference (MD), ?110.8 g; 95 % confidence intervals (95%CI), ?235.6 to 6.00; p?<?0.10) and shorter abdominal (MD, ?0.81 cm; 95%CI, ?1.64 to 0.00; p?<?0.05) and cephalic (MD, ?0.32 cm; 95%CI, ?0.65 to 0.00; p?<?0.05) circumferences at birth as well as with the presence of nucleoplasmic bridges (odds ratio, 1.03; 95%CI, 1.00 to 1.06; p?<?0.05) and nuclear buds (odds ratio, 1.02; 95%CI, 0.99 to 1.04; p?<?0.10). These associations were mainly confined to female babies, in whom paternal lead was also inversely associated with length. Our results support the hypothesis that paternal lead exposure may be affecting the development of newborns.  相似文献   
43.
The prenatal detection of scaphocephaly, an isolated form of craniosynostosis, is presented. The diagnosis was made at 34 weeks of gestation in a woman with polyhydramnios. The ultrasound appearance and postnatal follow-up are presented.  相似文献   
44.
The effect of resveratrol was studied on the life span and motor activity of Drosophila melanogaster treated with manganese (Mn). Two days after emerging from the pupa, male wild type D. melanogaster were fed for 13 days with corn media containing 15?mM Mn. Thereafter, Drosophila were divided into six groups of 300 flies each: (1) the flies remained treated with Mn; (2) began treatment with 0.43?mM resveratrol (Mn-resveratrol group); (3) received no additional treatment (Mn-no treatment group); (4) simultaneously fed with Mn and resveratrol (Mn?+?resveratrol group). In addition, a control (5) with no treatment and another group (6) fed only with resveratrol after emerging from the pupa were included. All Mn-treated flies (group 1) were dead on the 25th day. The life span in the resveratrol group was 91?±?0.33 days (mean?±?S.E.M.) and in Mn-resveratrol flies was 83?±?2 days. These two values were significantly higher than those detected in the control (5) and Mn-no treatment (group 3) flies whose life span were 68?±?0.33 and 67?±?2.31 days, respectively. The Mn?+?resveratrol-fed flies had a markedly higher life span (31?±?1.53 days) than Mn-fed flies (23?±?0.88 days). In the flies that received Mn (Mn and Mn?+?resveratrol groups), the motor activity decreased significantly with respect to control (groups 5) and the Mn–resveratrol and resveratrol groups. In conclusion, resveratrol increased significantly the life span of Mn-treated D. melanogaster.  相似文献   
45.
A central goal of comparative plant ecology is to understand how functional traits vary among species and to what extent this variation has adaptive value. Here we evaluate relationships between four functional traits (seed volume, specific leaf area, wood density, and adult stature) and two demographic attributes (diameter growth and tree mortality) for large trees of 240 tree species from five Neotropical forests. We evaluate how these key functional traits are related to survival and growth and whether similar relationships between traits and demography hold across different tropical forests. There was a tendency for a trade-off between growth and survival across rain forest tree species. Wood density, seed volume, and adult stature were significant predictors of growth and/or mortality. Both growth and mortality rates declined with an increase in wood density. This is consistent with greater construction costs and greater resistance to stem damage for denser wood. Growth and mortality rates also declined as seed volume increased. This is consistent with an adaptive syndrome in which species tolerant of low resource availability (in this case shade-tolerant species) have large seeds to establish successfully and low inherent growth and mortality rates. Growth increased and mortality decreased with an increase in adult stature, because taller species have a greater access to light and longer life spans. Specific leaf area was, surprisingly, only modestly informative for the performance of large trees and had ambiguous relationships with growth and survival. Single traits accounted for 9-55% of the interspecific variation in growth and mortality rates at individual sites. Significant correlations with demographic rates tended to be similar across forests and for phylogenetically independent contrasts as well as for cross-species analyses that treated each species as an independent observation. In combination, the morphological traits explained 41% of the variation in growth rate and 54% of the variation in mortality rate, with wood density being the best predictor of growth and mortality. Relationships between functional traits and demographic rates were statistically similar across a wide range of Neotropical forests. The consistency of these results strongly suggests that tropical rain forest species face similar trade-offs in different sites and converge on similar sets of solutions.  相似文献   
46.
A total of 168 bacterial strains isolated from soil of the La Laguna area (Tenerife Island, Spain) were characterized and assayed for phenol-oxidase enzymes (as an indicator of lignolytic capability).  相似文献   
47.
48.
Journal of Material Cycles and Waste Management - The present work produced bio-oil from the pyrolysis of sludge from the biodiesel processing industry in a fixed bed reactor, aiming at industrial...  相似文献   
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