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Iceberg discharges into the north atlantic on millennial time scales during the last glaciation 总被引：2，自引：0，他引：2
High-resolution studies of North Atlantic deep sea cores demonstrate that prominent increases in iceberg calving recurred at intervals of 2000 to 3000 years, much more frequently than the 7000-to 10,000-year pacing of massive ice discharges associated with Heinrich events. The calving cycles correlate with warm-cold oscillations, called Dansgaard-Oeschger events, in Greenland ice cores. Each cycle records synchronous discharges of ice from different sources, and the cycles are decoupled from sea-surface temperatures. These findings point to a mechanism operating within the atmosphere that caused rapid oscillations in air temperatures above Greenland and in calving from more than one ice sheet. 相似文献
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Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.3.
Stefano Pavan Zheng Zheng Mariya Borisova Petra van den Berg Concetta Lotti Claudio De Giovanni Pim Lindhout Hans de Jong Luigi Ricciardi Richard G. F. Visser Yuling Bai 《Euphytica》2008,162(1):91-98
The recessive gene ol-2 confers papilla-associated and race-non-specific resistance to tomato powdery mildew caused by Oidium neolycopersici. In order to facilitate marker assisted selection (MAS) in practical breeding programmes, we identified two simple sequence repeat (SSR) markers and one cleaved amplified polymorphic sequence (CAPS) marker which are linked to the resistance locus and co-dominantly inherited. Aiming to provide a base for ol-2 positional cloning, we used a large segregating F2 population to merge these markers with all the ol-2 linked amplified fragment length polymorphism (AFLP®) markers previously identified in an integrated genetic map. By screening a tomato bacterial artificial chromosome (BAC) library, we detected two BAC clones containing two expressed sequence tags (ESTs) homologous to the gene mlo, responsible for powdery mildew resistance in barley, as well as an ol-2-linked marker. Chromosomal mapping by Fluorescence in situ Hybridization (FISH) revealed major signals of the two BAC DNAs in the pericentromeric heterochromatin of the short arm of chromosome 4, in the same region where the ol-2 gene was previously mapped. The genetic and cytogenetic co-localisation between ol-2 and tomato mlo-homologue(s), in addition to the similarity of ol-2 and mlo resistances for both genetic and phytopathological characteristics, suggests that ol-2 is likely a mlo-homologue. Thus, a homology-based cloning approach could be more suitable than positional cloning for ol-2 isolation. 相似文献
4.
Donatella Lotti DVM PhD Maria Tresa Capucchio DVM Elena Gaidolfi DM Monica Merlo DVM 《Veterinary radiology & ultrasound》1999,40(6):622-626
A 5-year-old, male Yorkshire Terrier had chronic and progressive neurologic signs compatible with lesions in the right brain stem and right forebrain. In magnetic resonance images of the brain there were multifocal lesions at different stages of evolution, consistent with an inflammatory disease. The lesions were located in the white matter of the cerebrum, in the diencephalon and mesencephalon. These lesions were hypointense in T1-weighted images and hyperintense in T2-weighted images with no mass effect and minimal enhancement with gadolinium. Necrotizing encephalitis was confirmed post mortem. 相似文献
5.
Amplified fragment length polymorphism (AFLP) is a powerful technique which can readily be applied to a wide range of species for mapping purposes. AFLPs were added to a linkage map of durum wheat constructed using restriction fragment length polymorphisms (RFLPs). The mapping population included 65 recombinant inbred lines derived from a cross between the durum wheat cultivar ‘Messapia’ and accession ‘MG4343’ of the wild Triticum turgidum ssp. dicoccoides (Körn.). Genomic DNA was digested with MseI (4‐cutter) and Sse83871 (8‐cutter). Using a silver‐staining protocol, 14 primer combinations revealed 421 clearly scorable amplicons including 100 polymorphisms. The presence of nine pairs of bands linked in repulsion phase with each pair generated by one primer combination suggested the presence of codominant alleles; sequence analysis of four band pairs confirmed their codominant nature. The integration of 80 AFLP loci extended the map in several telomeric regions, reduced the size of four large gaps present in the previous map, and eliminated one gap. The new map obtained after the inclusion of the 80 AFLP loci and eight additional RFLP loci spans 2063cM which represent a 52.6% increment compared with the previous map. Compared with the distribution of RFLPs, no significant clustering of AFLP markers was observed. 相似文献
6.
Piccinelli AL Lotti C Campone L Cuesta-Rubio O Campo Fernandez M Rastrelli L 《Journal of agricultural and food chemistry》2011,59(12):6484-6491
Chemical composition of propolis depends on the specificity of the local flora at the site of collection and thus on the geographic and climatic characteristics of this place. This paper describes a comparative analysis of Cuban red propolis (CRP), Brazilian red propolis (BRP), and Dalbergia ecastophyllum exudates (DEE) by high-performance liquid chromatography with diode-array detection and tandem mass spectrometry. The aim of this study was to investigate the overall chemical profile and the botanical origin of red propolis and to suggest similarities and differences between samples collected in different tropical regions. Isoliquiritigenin (1), liquiritigenin and naringenin (2 and 17), isoflavones (3-4 and 16), isoflavans (5-7 and 18), and pterocarpans (8-13) were detected in CRP, BRP, and DEE, whereas polyisoprenylated benzophenones (PPBs) guttiferone E/xanthochymol (14a,b) and oblongifolin A (15) were detected only in BRP. Pigments responsible for the red color of DEE and red propolis were also identified as two C30 isoflavans, the new retusapurpurin B (19) and retusapurpurin A (20). PPBs and pigments were isolated and unambiguously characterized by 1D and 2D NMR analysis. These results show that red propolis samples from different tropical zones have a similar chemical composition. DEE is the main red propolis source, but the presence of PPBs in BRP suggests the contribution of different botanical sources for Brazilian samples. This chemical information is important for quality control of red propolis and its commercial products and for biological study. 相似文献
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C. Lotti A. R. Marcotrigiano C. De Giovanni P. Resta A. Ricciardi V. Zonno G. Fanizza L. Ricciardi 《Genetic Resources and Crop Evolution》2008,55(4):511-522
A large collection of melon (Cucumis melo L.) germplasm has been established at the Section of Genetics and Plant Breeding, Bari University (Italy). In the present
work, data regarding the variation of 20 bio-agronomical traits recorded on entries and landraces collected in Albania and
Apulia region (Southern Italy) are reported. The main objective of the study was to assess and describe, by means of univariate
and multivariate analyses, the genetic diversity in the collection composed by genotypes classified in the Inodorus and Cantalupensis groups. The results obtained showed a large variation for all the traits examined. Furthermore, it was possible to identify
valuable genotypes for future breeding programmes aimed at improving melon traits, particularly for the Inodorus group, which is an important crop in many Southern Italian sites. Genotypes of interest were especially selected for earliness
and lateness, fruit shape, soluble solids content, storage time and fruit firmness. 相似文献
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