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151.
152.
Juhani Kaakinen Toivo Kuokkanen Janne Pesonen Ilkka Välimäki 《Soil & Sediment Contamination》2014,23(4):437-451
The mining industry is a very rapidly increasing production sector in Finland. Many new mines have been opened recently and others are in the planning phase. Mining legislation has been recently revised and compilation of an ID-directive (Industrial Emission Directive, 2010) required to implement environmental law revision is in progress. The aim of this study was to compare different digestion methods recommended by the Finnish Environmental Administration for threshold and guideline value determinations in the Finnish PIMA Decree (214/2007) and Government Decree (591/2006) concerning recovery of certain wastes in earth construction. Altogether six methods were tested, of which five were microwave-assisted acid digestion methods: ISO 11466, EPA Method 3051A (aqua region), EPA Method 3051A (HNO3), EPA Method 3051A (HNO3/HCl), and SFS-EN 13656, while one was a fusion method with lithium tetraborate (ASTM C 1391 - 95). The results showed that concentrations of heavy metals (As, Cd, Co, Cu, Ni, Pb, Sb, V, and Zn) can be determined reproducibly with standard methods, but the chemical method used can have a significant impact on the results. This conclusion is very important, because the measured heavy metal values can affect the classification and processing of waste materials, and thereby can significantly impact the cost of treatment. 相似文献
153.
Dr. M. Nurminen 《Biometrical journal. Biometrische Zeitschrift》1987,29(4):413-421
Breslow (1984) described an efficient score test for trend in incidence density rate ratios for cohort studies under a conditional Poisson or binomial model employing maximum likelihood estimation of the rate parameters. In this communication, an alternative derivation of this statistic that is based on an unconditional approach is provided, along with an examination of associated goodness-of-fit tests and methods of confidence interval estimation. The procedures are illustrated by a cohort study of ischemic heart disease mortality following industrial exposure to carbon disulfide. 相似文献
154.
Johannes F. Scheid Christopher O. Barnes Basak Eraslan Andrew Hudak Jennifer R. Keeffe Lisa A. Cosimi Eric M. Brown Frauke Muecksch Yiska Weisblum Shuting Zhang Toni Delorey Ann E. Woolley Fadi Ghantous Sung-Moo Park Devan Phillips Betsabeh Tusi Kathryn E. Huey-Tubman Alexander A. Cohen Ramnik J. Xavier 《Cell》2021,184(12):3205-3221.e24
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155.
The breeding biology of the starling Sturnus vulgaris was studied in three populations in northern Finland, with additional reference localities in nearby areas. Results from a total of 329 nests are presented from years 1962-1976.
The onset of laying in the Oulu area took place on 5 May, the median date being 10 May, about one week later than in southern Finland and 2–3 weeks later than in central Europe. The clutch-size was 5.29 ± 0.05 in the first nests and 5.06 ± 0.26 in later ones. Incubation time was 12.1 ± 0.6 d. An average of 3.31 ± 0.10 fledglings was produced per pair, 3.69 ± 0.08 in succesful clutches, which is significantly less than usually reported from central Europe. Most of the losses were due to starvation of the young.
No second broods were observed in the Oulu area, and repeated nesting was not common, probably because of the general late start of laying.
The reasons for the recent decline in several Finnish starling populations do not lie in the production capacity but must be sought for elsewhere. 相似文献
The onset of laying in the Oulu area took place on 5 May, the median date being 10 May, about one week later than in southern Finland and 2–3 weeks later than in central Europe. The clutch-size was 5.29 ± 0.05 in the first nests and 5.06 ± 0.26 in later ones. Incubation time was 12.1 ± 0.6 d. An average of 3.31 ± 0.10 fledglings was produced per pair, 3.69 ± 0.08 in succesful clutches, which is significantly less than usually reported from central Europe. Most of the losses were due to starvation of the young.
No second broods were observed in the Oulu area, and repeated nesting was not common, probably because of the general late start of laying.
The reasons for the recent decline in several Finnish starling populations do not lie in the production capacity but must be sought for elsewhere. 相似文献
156.
The advent of publishing anonymized call detail records opens the door for temporal and spatial human dynamics studies. Such studies, besides being useful for creating universal models for mobility patterns, could be also used for creating new socio-economic proxy indicators that will not rely only on the local or state institutions. In this paper, from the frequency of calls at different times of the day, in different small regional units (sub-prefectures) in Côte d''Ivoire, we infer users'' home and work sub-prefectures. This division of users enables us to analyze different mobility and calling patterns for the different regions. We then compare how those patterns correlate to the data from other sources, such as: news for particular events in the given period, census data, economic activity, poverty index, power plants and energy grid data. Our results show high correlation in many of the cases revealing the diversity of socio-economic insights that can be inferred using only mobile phone call data. The methods and the results may be particularly relevant to policy-makers engaged in poverty reduction initiatives as they can provide an affordable tool in the context of resource-constrained developing economies, such as Côte d''Ivoire''s. 相似文献
157.
158.
Phenological sensitivity to climate change is higher in resident than in migrant bird populations among European cavity breeders
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Jelmer M. Samplonius Lenka Bartošová Malcolm D. Burgess Andrey V. Bushuev Tapio Eeva Elena V. Ivankina Anvar B. Kerimov Indrikis Krams Toni Laaksonen Marko Mägi Raivo Mänd Jaime Potti János Török Miroslav Trnka Marcel E. Visser Herwig Zang Christiaan Both 《Global Change Biology》2018,24(8):3780-3790
Many organisms adjust their reproductive phenology in response to climate change, but phenological sensitivity to temperature may vary between species. For example, resident and migratory birds have vastly different annual cycles, which can cause differential temperature sensitivity at the breeding grounds, and may affect competitive dynamics. Currently, however, adjustment to climate change in resident and migratory birds have been studied separately or at relatively small geographical scales with varying time series durations and methodologies. Here, we studied differential effects of temperature on resident and migratory birds using the mean egg laying initiation dates from 10 European nest box schemes between 1991 and 2015 that had data on at least one resident tit species and at least one migratory flycatcher species. We found that both tits and flycatchers advanced laying in response to spring warming, but resident tit populations advanced more strongly in relation to temperature increases than migratory flycatchers. These different temperature responses have already led to a divergence in laying dates between tits and flycatchers of on average 0.94 days per decade over the current study period. Interestingly, this divergence was stronger at lower latitudes where the interval between tit and flycatcher phenology is smaller and winter conditions can be considered more favorable for resident birds. This could indicate that phenological adjustment to climate change by flycatchers is increasingly hampered by competition with resident species. Indeed, we found that tit laying date had an additional effect on flycatcher laying date after controlling for temperature, and this effect was strongest in areas with the shortest interval between both species groups. Combined, our results suggest that the differential effect of climate change on species groups with overlapping breeding ecology affects the phenological interval between them, potentially affecting interspecific interactions. 相似文献
159.
Kaidi Lõo Juhani Järvikivi Fabian Tomaschek Benjamin V. Tucker R. Harald Baayen 《Morphology》2018,28(1):71-97
Most psycholinguistic models of lexical processing assume that the comprehension and production of inflected forms is mediated by morphemic constituents. Several more recent studies, however, have challenged this assumption by providing empirical evidence that information about individual inflected forms and their paradigmatic relations is available in long-term memory (Baayen et al. 1997; Milin et al. 2009a, 2009b). Here, we investigate how whole-word frequency, inflectional paradigm size and morphological family size affect production latencies and articulation durations when subjects are asked to read aloud isolated Estonian case-inflected nouns. In Experiment 1, we observed that words with a larger morphological family elicited shorter speech onset latencies, and that forms with higher whole-word frequency had shorter acoustic durations. Experiment 2, for which we increased statistical power by using 2,800 words, revealed that higher whole-word frequency, inflectional paradigm size, and morphological family size reduced both speech onset times and acoustic durations. These results extend our knowledge of morphological processing in three ways. First, whole-word frequency effects of inflected forms in morphologically rich languages are not restricted to a small number of very high-frequency forms, contrary to previous claims (Niemi et al. 1994; Hankamer 1989; Yang 2016). Second, we replicated the morphological family size effect in a new domain, the acoustic durations of inflected forms. Third, we showed that a novel paradigmatic measure, inflectional paradigm size, predicts word naming latencies and acoustic durations. These results fit well with Word-and-Paradigm morphology (Blevins 2016) and argue against strictly (de)compositional models of lexical processing. 相似文献
160.
Melittin-induced leakage from phosphatidylcholine vesicles is modulated by cholesterol: a property used for membrane targeting 总被引:4,自引:0,他引:4
Toni Benachir M. Monette Julie Grenier M. Lafleur 《European biophysics journal : EBJ》1997,25(3):201-210
Melittin, an amphiphathic peptide, affects the permeability of vesicles. This can be demonstrated using the dye release technique.
Calcein, a fluorescent marker, is trapped in large unilamellar 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) vesicles and
melittin-induced leakage of the dye can be monitored directly by increasing fluorescence intensity. First, we characterized
the effect of increasing cholesterol content in the membrane on melittin-induced leakage and our results reveal that cholesterol
inhibits the lytic activity of the peptide. Using intrinsic fluorescence of the single tryptophan of melittin and 2H-NMR of headgroup deuterated phosphatidylcholine, we demonstrated that the affinity of melittin for phosphatidylcholine vesicles
is reduced in the presence of cholesterol; this is associated with the tighter lipid packing of the cholesterol-containing
bilayer. This reduced binding is responsible for the reduced melittin-induced leakage from cholesterol-containing membranes.
The pathway of release was determined to be an all-or-none mechanism. Finally, we investigated the possibility of achieving
specific membrane targeting with melittin, when vesicles of different lipid composition are simultaneously present. Melittin
incubated together with vesicles made of pure POPC and POPC containing 30(mol)% cholesterol can empty nearly all the cholesterol-free
vesicles while the cholesterol-containing vesicles remain almost intact. Owing to the preferential interaction of melittin
with the pure POPC vesicles, we were able to achieve controlled release of encapsulated material from a specific vesicle population.
Received: 8 May 1996 / Accepted: 12 September 1996 相似文献