Transcriptome analyses of Populus x euramericana clone I-214 leaves exposed to excess zinc     

Di Baccio D  Galla G  Bracci T  Andreucci A  Barcaccia G  Tognetti R  Sebastiani L 《Tree physiology》2011,31(12):1293-1308

  相似文献   

A soil chronosequence in the semi-arid environment of Patagonia (Argentina)     

Daniela Sauer  Gerhard Schellmann  Karl Stahr 《CATENA》2007,71(3):382

Soil development with time was investigated on beach ridges with ages ranging from about 1380 to 6240 ¹⁴C-years BP at the eastern coast of central Patagonia. The main pedogenic processes are accumulation of organic matter and carbonate leaching and accumulation within the upper part of the soils. Soil formation is strongly influenced by incorporation of eolian sediments into the interstitial spaces between the gravel of which the beach ridges are composed. Different amounts of eolian material in the soils lead to differentiation into Leptosols (containing ≤ 10% fine earth in the upper 75 cm) and Regosols (containing > 10% fine earth). Soil depth functions and chronofunctions of organic carbon, calcium carbonate, pH, Ca:Zr, Mg:Zr, K:Zr, Na:Zr, Fe:Zr, Mn:Zr, and Si:Al (obtained from X-ray fluorescence analysis) were evaluated. To establish soil chronofunctions mean values of the horizon data of 0–10 cm below the desert pavement were used, which were weighted according to the horizon thicknesses. The depth function of pH shows a decrease towards the surface, indicating leaching of bases from the upper centimeters. Chronofunctions of pH show that within 6000 radiocarbon years of soil development pH drops from 7.0 to 6.6 in the Leptosols and from 8.1 to 7.5 in the Regosols. The higher pH of the Regosols is due to input of additional bases from the eolian sediments. Chronofunctions of Ca:Zr and K:Zr indicate progressive leaching of Ca and K in the Regosols, showing close relationships to time (R² = 0.972 and 0.995). Na leaching as indicated by decreasing Na:Zr ratios shows a strong correlation to time only in the Leptosols (R² = 0.999). Both, Leptosols and Regosols show close relationships to time for Fe:Zr (R² = 0.817 and 0.824), Mn:Zr (R² = 0.940 and 0.803), and Si:Al (0.971 and 0.977), indicating enrichment of Fe and Mn and leaching of Si. Leaching of mobile elements takes place on a higher level in the Regosols than in the Leptosols from the beginning of soil formation. Hence, a significant part of the eolian sediments must have been incorporated into the beach ridges very soon after their formation.  相似文献   

Composition of suberin extracted upon gradual alkaline methanolysis of Quercus suber L. cork     

Lopes MH  Gil AM  Silvestre AJ  Neto CP 《Journal of agricultural and food chemistry》2000,48(2):383-391

The monomeric composition of suberin extracts obtained by gradual alkaline methanolysis of Quercus suber cork was determined by gas chromatography-mass spectrometry (GC-MS). Results show that 1-alkanols and alkanoic and alpha,omega-alkanedioic acids are preferentially removed upon mild alkaline conditions, whereas mid-chain-modified omega-hydroxyalkanoic acids are preferentially removed under stronger alkaline conditions. Saturated omega-hydroxyalkanoic acids are found to be abundant in all suberin extracts. These results are consistent with two distinct suberin fractions with different locations in cork cell walls and/or esterification degrees. It is proposed that these fractions correlate with the two main suberin peaks in the solid state (13)C NMR spectra of cork and suberin extracts. Quantitative GC-MS analysis showed that suberin monomers comprise approximately 30% (w/w) of the suberin extracts, the remaining comprising nonvolatile structures with high M(n) values, as measured by vapor pressure osmometry. The presence of a large fraction of high molecular weight aliphatic structures in suberin extracts is supported by the corresponding NMR spectra.  相似文献   

The self-incompatible RNase S-alleles of Brazilian apple cultivars   总被引：1，自引：0，他引：1  

Celso Lopes de Albuquerque  Frederico Denardi  Adriana Cibele de Mesquita Dantas  Rubens Onofre Nodari 《Euphytica》2011,181(2):277-284

Apple plants are self-incompatible because a genetic mechanism allows the female reproductive organ to recognize and reject self-pollen or pollen from genetic related individuals and allows non-self pollen to effect fertilization. Thus, there are implications to both breeding strategies and orchard management for fruit production. The purpose of this study was to identify and to characterize the S-RNase alleles of the gametophytic incompatibility among apple cultivars developed in Brazil, seeking to give support for choosing right combinations of parent in the apple breeding programs. It also sought to identify correct combinations of scion/pollinator cultivars of commercial apple orchards. A total of 16 specific S-RNase alleles primers were tested against DNA extracted from 12 Brazilian cultivars and their parents. The molecular analysis confronted to the reference cultivars, showed that the cultivars Daiane, Imperatriz and Princesa have the same incompatibility S3 and S5 alleles, while ‘Lisgala’ showed the alleles S2 and S5; ‘Suprema’, S1 and S9; ‘Catarina’, S1 and S19; ‘Joaquina’ and ‘Fred Hough’, S5 and S19; ‘Baronesa’, S3 and S9; ‘Duquesa’, S2 and S3. For ‘Primícia’ and ‘Condessa’ it was only possible to identify one of the S-alleles, namely S24 and S2, respectively, with the second allele remaining to be identified. Progeny test indicated the Mendelian inheritance for RNase alleles. Results of this study will be helpful to judiciously choose parents in apple breeding programs to improve compatibility.  相似文献   

Io volcanism seen by new horizons: a major eruption of the Tvashtar volcano     

Spencer JR  Stern SA  Cheng AF  Weaver HA  Reuter DC  Retherford K  Lunsford A  Moore JM  Abramov O  Lopes RM  Perry JE  Kamp L  Showalter M  Jessup KL  Marchis F  Schenk PM  Dumas C 《Science (New York, N.Y.)》2007,318(5848):240-243

Jupiter's moon Io is known to host active volcanoes. In February and March 2007, the New Horizons spacecraft obtained a global snapshot of Io's volcanism. A 350-kilometer-high volcanic plume was seen to emanate from the Tvashtar volcano (62 degrees N, 122 degrees W), and its motion was observed. The plume's morphology and dynamics support nonballistic models of large Io plumes and also suggest that most visible plume particles condensed within the plume rather than being ejected from the source. In images taken in Jupiter eclipse, nonthermal visible-wavelength emission was seen from individual volcanoes near Io's sub-Jupiter and anti-Jupiter points. Near-infrared emission from the brightest volcanoes indicates minimum magma temperatures in the 1150- to 1335-kelvin range, consistent with basaltic composition.  相似文献   

Mitotic Golgi partitioning is driven by the membrane-fissioning protein CtBP3/BARS     

Hidalgo Carcedo C  Bonazzi M  Spanò S  Turacchio G  Colanzi A  Luini A  Corda D 《Science (New York, N.Y.)》2004,305(5680):93-96

Organelle inheritance is an essential feature of all eukaryotic cells. As with other organelles, the Golgi complex partitions between daughter cells through the fission of its membranes into numerous tubulovesicular fragments. We found that the protein CtBP3/BARS (BARS) was responsible for driving the fission of Golgi membranes during mitosis in vivo. Moreover, by in vitro analysis, we identified two stages of this Golgi fragmentation process: disassembly of the Golgi stacks into a tubular network, and BARS-dependent fission of these tubules. Finally, this BARS-induced fission of Golgi membranes controlled the G2-to-prophase transition of the cell cycle, and hence cell division.  相似文献   

Radar soundings of the subsurface of Mars   总被引：2，自引：0，他引：2  

Picardi G  Plaut JJ  Biccari D  Bombaci O  Calabrese D  Cartacci M  Cicchetti A  Clifford SM  Edenhofer P  Farrell WM  Federico C  Frigeri A  Gurnett DA  Hagfors T  Heggy E  Herique A  Huff RL  Ivanov AB  Johnson WT  Jordan RL  Kirchner DL  Kofman W  Leuschen CJ  Nielsen E  Orosei R  Pettinelli E  Phillips RJ  Plettemeier D  Safaeinili A  Seu R  Stofan ER  Vannaroni G  Watters TR  Zampolini E 《Science (New York, N.Y.)》2005,310(5756):1925-1928

The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick.  相似文献   

Mass spectrometry of intact V-type ATPases reveals bound lipids and the effects of nucleotide binding     

Zhou M  Morgner N  Barrera NP  Politis A  Isaacson SC  Matak-Vinković D  Murata T  Bernal RA  Stock D  Robinson CV 《Science (New York, N.Y.)》2011,334(6054):380-385

The ability of electrospray to propel large viruses into a mass spectrometer is established and is rationalized by analogy to the atmospheric transmission of the common cold. Much less clear is the fate of membrane-embedded molecular machines in the gas phase. Here we show that rotary adenosine triphosphatases (ATPases)/synthases from Thermus thermophilus and Enterococcus hirae can be maintained intact with membrane and soluble subunit interactions preserved in vacuum. Mass spectra reveal subunit stoichiometries and the identity of tightly bound lipids within the membrane rotors. Moreover, subcomplexes formed in solution and gas phases reveal the regulatory effects of nucleotide binding on both ATP hydrolysis and proton translocation. Consequently, we can link specific lipid and nucleotide binding with distinct regulatory roles.  相似文献   

The paradox of the conservation of an endangered fish species in a Mediterranean region under agricultural intensification     

J. Jesús Casas  Juan S. Sánchez-Oliver  Ana Sanz  Miriam Furné  Cristina Trenzado  Melchor Juan  Mariano Paracuellos  María D. Suárez  Francisca Fuentes  Irene Gallego  Carlos Gil  José J. Ramos-Miras 《Biological conservation》2011,(1):253-262

We studied the relative value of natural habitats, river and coastal wetlands, and artificial habitats, irrigation canal and ponds, for the conservation of an endangered fish, Iberian toothcarp, in its southernmost area of distribution, characterised by agricultural intensification. Our results show that the bulk of the population of the Iberian toothcarp is concentrated in irrigation ponds. Natural habitats sustained null or impoverished subpopulations, and individuals showed signs of low metabolic activity. This coincided with the relatively high habitat quality observed in ponds, particularly those with submerged aquatic vegetation, in contrast with the chronic eutrophication of the coastal lagoons. In spite of a generalised aggressive management in the irrigation system, featured by periodic vegetation clearance, desiccation and biocide treatment, the subpopulation of the Iberian toothcarp thrives in it probably thanks to adequate water quality and to an active path dynamics maintained by connectivity through the canal. Agro-environmental measures are discussed for the improvement of this species conservation in natural and artificial habitats.  相似文献   

Long-term effect of toltrazuril on growth performances of dairy heifers and beef calves exposed to natural Eimeria zuernii and Eimeria bovis infections     

Veronesi F  Diaferia M  Viola O  Fioretti DP 《Veterinary journal (London, England : 1997)》2011,190(2):296-299

The long-term effects of a toltrazuril treatment against natural Eimeria bovis and/or Eimeria zuernii infections were investigated in comparison with diclazuril and untreated controls on two dairy (Italian Friesian breed) and two beef (Chianina breed) farms. At each trial site, 30 calves were allocated into three groups of 10 calves each: T (treated with toltrazuril), D (treated with diclazuril) and C (left untreated). For 40 weeks post-treatment, the calves were weighed and examined clinically and parasitologically. The oocyst counts as well as the number of scour days were significantly lower in the T group than in the D and C groups. Final bodyweights and body condition scores of the T group exceeded those of groups C and D. The results confirmed that toltrazuril was highly efficacious, safe and provided productive benefits in dairy and beef calves.  相似文献