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1.
The faunas collected in the Miocene of the Centralpart of the Jura High-Range near Pontarlier have allowed to attribute a Burdigalien age at the marine molass and Upper Burdigalien age at the overlying lacustrine deposits. The marine faunas are varied and show very clearly sea-ways from the rhodanoprovencal area. The age of the continental faunas prove that the sea recedes as soon as the end of Lower Miocene, showing the beginning of the emersion of the High-Range is an earliest event than hitherto believed.  相似文献   

2.
New paleontological data on Sestrosphaera liasina (Pia) based on material collected in the type-locality, Malga Mandrielle (Italian Southern Alps) are supplied. All the features of the alga are reexamined; the occurrence in the stalk region of an unusual primary lateral inner swelling is confirmed. The structure formed by the inner enlarged portion of the laterals is here indicated as inner pseudocortex. A new diagnosis of S. liasina is proposed and a lectotype is chosen from Pia's material. Finally, a paleontological reconstruction is supplied taking into account all the main biometrical values.  相似文献   

3.
Zusammenfassung Die Polyalkohole Sorbitol, d-Mannitol, Ribitol, Xylitol, d-Arabitol, l-Arabitol und Erythritol werden von der obligat aeroben Hefe Rhodotorula gracilis über einen beweglichen Träger in der Zellmembran aufgenommen. Der Transportmechanismus ist aktiv, das erreichte Akkumulationsverhältnis ist jedoch bei allen Polyalkoholen erheblich geringer als bei Monosacchariden. Es nimmt, wie auch bei Monosacchariden, mit steigender Außenkonzentration ab, sogar auf Werte kleiner als 1.Kinetische Daten weisen darauf hin, daß das Trägersystem für Polyalkohole identisch ist mit dem für Monosaccharide, jedoch für Polyalkohole eine wesentlich geringere Affinität und maximale Geschwindigkeit aufweist. Aufgrund des hohen Affinitätsunterschiedes wird die Polyalkoholaufnahme in der Anwesenheit von Monosacchariden unterbunden.Die aufgenommenen Polyalkohole werden im Zellinneren nicht umgesetzt; eine Ausnahme stellen Ribitol und l-Arabitol dar, in deren Anwesenheit ein Abbausystem für Pentitole induziert wird.
Transport and utilization of alditols in the yeast Rhodotorula gracilis (glutinis)I. Constitutive transport of alditols
The obligate aerobic yeast Rhodotorula gracilis was found to take up the alditols d-glucitol, d-mannitol, ribitol, xylitol, d-arabinitol, l-arabinitol and erythritol by means of a constitutive mobile membrane carrier. This uptake involved active transport, that is, it was dependent on the supply of metabolic energy, leading to the accumulation of alditols inside the cells. The accumulation ratio (intracellular concentration to extracellular concentration, Si/So) was much lower for alditols than for monosaccharides. As for monosaccharides, this ratio decreased with increasing extracellular concentration, even to values below 1.The kinetic data showed that the carrier system for alditols was identical to that for monosaccharides, though it had a much lower affinity and maximum velocity for alditols. Hence the uptake of alditols was blocked in the presence of monosaccharides.Only ribitol and l-arabinitol were catabolized following enzyme induction. The other alditols were not broken down.
  相似文献   

4.
The structure, stability, and the IR, and EPR spectroscopic properties of bis(methoxyacetato)diaquo-copper(II) were studied both experimentally using FT-IR and theoretically using B3LYP/6-31G**, B3LYP/6-311G, BWP91/6-31G** methods. The same approaches were used to calculate the harmonic frequencies and to compare them to the experimental solid state values. The g-tensors are calculated using the NMR/GIAO computational method.  相似文献   

5.
Reaction of pyridine-2,6-dicarboxylic acid (dipicH2) with ammonium ceric nitrate and Cu(II) salts yielded three heterometallic compounds all of which contain [Ce(dipic)3]2− linked to aquo-Cu(II) complex units. Part of the Ce(IV) gets reduced by solvent during the reaction leading to [(Ce(dipic)3Ce(H2O)8)2Cu(H2O)4][Ce(dipic)3]2·12H2O (1). Other lanthanide(III) ions could take the place of Ce(III) as demonstrated by the preparation of [(Ce(dipic)3La(H2O)8)2Cu(H2O)4][Ce(dipic)3]2·12H2O (4), which is isomorphous with compound 1. [Ce(dipic)3Cu(H2O)4]·8H2O (2) is a one-dimensional coordination polymer in which two types of aquo-Cu(II) complex units which differ in the orientation of the tetragonal axis alternate along the chain. The central Cu(H2O)22+ unit in the trinuclear anion of [Cu(H2O)6][Ce(dipic)3Cu(H2O)2Ce(dipic)3]·8H2O (3) is chelated by two carboxylate groups in trans positions in off-axis mode. In all the four complexes, the Cu(II) centres are magnetically isolated leading well-resolved EPR spectra in polycrystalline samples.  相似文献   

6.
The steady-state kinetics of alcohol dehydrogenases (alcohol:NAD+ oxidoreductase, EC 1.1.1.1 and alcohol:NADP+ oxidoreductase, EC 1.1.1.2), lactate dehydrogenases (l-lactate:NAD+ oxidoreductase, EC 1.1.1.27 and d-lactate:NAD+ oxidoreductase, EC 1.1.1.28), malate dehydrogenase (l-malate:NAD+ oxidoreductase, EC 1.1.1.37), and glyceraldehyde-3-phosphate dehydrogenases [d-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12] from different sources (prokaryote and eukaryote, mesophilic and thermophilic organisms) have been studied using NAD(H), N6-(2-carboxyethyl)-NAD(H), and poly(ethylene glycol)-bound NAD(H) as coenzymes. The kinetic constants for NAD(H) were changed by carboxyethylation of the 6-amino group of the adenine ring and by conversion to macromolecular form. Enzymes from thermophilic bacteria showed especially high activities for the derivatives. The relative values of the maximum velocity (NAD = 1) of Thermus thermophilus malate dehydrogenase for N6-(2-carboxyethyl)-NAD and poly(ethylene glycol)-bound NAD were 5.7 and 1.9, respectively, and that of Bacillus stearothermophilus glyceraldehyde-3-phosphate dehydrogenase for poly(ethylene glycol)-bound NAD was 1.9.  相似文献   

7.
Zusammenfassung Im Einklang mit neuen Befunden von Hafeez (1971) bei Symphysodon aequifasciatus (Cichlidae) gehört das Pinealorgan von Pterophyllum scalare1 zum tubulärsensorischen Typ der Knochenfischepiphyse. — In Versuchen mit elektrophysiologischer Ableitung vom freigelegten Epiphysenstiel wurde eine direkte Lichtempfindlichkeit des Pinealorgans von Pterophyllum scalare beobachtet. Die Wirkung bestand in der Regel in einer Hemmung der Spontanaktivität, für die ein Photopigment mit einem Absorptionsmaximum bei 530 nm verantwortlich sein dürfte. Die Bestimmung der Lichtschwelle ergab Werte, die bei Berücksichtigung der Lichtverluste dafür sprechen, daß das Pinealorgan von Pterophyllum scalare bei Dunkelheit und in der Dämmerung aktiv ist, während die Impulsaussendung im vollen Tageslicht gehemmt wird. — Die Ableitungsstellen wurden an Hand von elektrolytisch gesetzten Eisenmarken histologisch lokalisiert.
Physiological studies and some further remarks on the structure of the photosensitive pineal organ of Pterophyllum scalare Cuv. et Val. (Cichlidae, Teleostei)
Summary The pineal organ of Pterophyllum scalare was classified as tubular and sensory. Our anatomical findings are in agreement with recent observations of Hafeez (1971) in Symphysodon aequifasciatus (Cichlidae). Electrical recordings from the exposed pineal stalk of Pterophyllum scalare, after removal of the lateral eyes and upon direct illumination of the diencephalic roof, indicated that: (1) the pineal organ of P. scalare is photosensitive, and (2) light mainly inhibits the spontaneous discharge of its nervous elements. Maximum sensitivity was observed at 525 nm. Prom estimates of the light absorbed by the tissue in front of the pineal organ and measurements of the light threshold of the exposed organ, it was concluded that the pineal organ of Pterophyllum scalare functions optimally in dim light, and that its activity is inhibited in daylight. The site of the recording electrodes was identified histologically by electrolytically-deposited iron marks.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft (Arbeitskreise E. Dodt und A. Oksche).  相似文献   

8.
Phosphinoquinoxalines were prepared by treatment of 2,3-dichloroquinoxaline (3) with phosphorus nucleophiles. The Arbuzov reaction of 3 with PPh(O-i-Pr)2 gave a mixture of diastereomers of 2,3-(PPh(O)(O-i-Pr))2quinoxaline (6); the crystal structure of rac-6 was determined, but attempts at reduction to yield bis(phenylphosphino)quinoxaline 7 resulted in P-C cleavage and formation of phenylphosphine. The bis(secondary phosphine) 7 could be generated from 3 and LiPHPh(BH3), but was not isolated in pure form. Copper-catalyzed coupling of PHPh2 with 3 gave 2,3-bis(diphenylphosphino)quinoxaline (4, dppQx), whose coordination chemistry was investigated, with comparison to data for the analogous 1,2-bis(diphenylphosphino)benzene (dppBz) complexes. Reaction of dppQx with [Cu(NCMe)4][PF6] gave [Cu(dppQx)2][PF6] (8); CuCl yielded [Cu(dppQx)Cl]2 (9). Reaction of [Cu(NCMe)4][PF6] with one equiv of DPEphos, followed by one equiv of dppQx, gave [Cu(dppQx)(DPEphos)][PF6] (10). Ligand 4 and copper complexes 8 and 9 were crystallographically characterized. The UV-Vis spectra of dppQx and its copper complexes were red-shifted from those of the dppBz analogs; in contrast to results for the dppBz complexes, those of dppQx were not luminescent in solution.  相似文献   

9.
三种免疫制剂对真鲷弧菌病的免疫保护性   总被引:6,自引:3,他引:6  
菌体疫苗按不同的方式对真鲷进行免疫2周后,对实验鱼均具有免疫保护性,免疫保护性最好的免疫组,免疫保护率在初次免疫后高达60%,强化免疫后免疫保护率可提高到80%;粗制LPS经去毒处理后初次免疫真鲷,不同浓度的LPS对实验鱼具有不同程度的免疫保护性,强化免疫后,免疫保护率均有明显的提高,浓度越高,免疫保护性越强,对真鲷的免疫保护率最高可达90%,最小弧菌产生的外毒素经福尔马林灭活后制成毒素苗,这种毒素苗能产生较好的免疫保护性,其免疫保护率可达80%,这表明外毒素不仅是最小弧菌产生的毒力因子,同时也是菌体产生的有效保护性抗原。  相似文献   

10.
Upper Jurassic reefs rich in microbial crusts generally appear in deeper (sponge—‘algal’ crust reefs) or in very shallow but protected settings (coral or coral-coralline sponge meadows with ‘algal’ crusts). Upper Jurassic high-energy reefs (coral reefs and coral-stromatoporoid reefs) normally lack major participation of microbial crusts but rather represent huge bioclastic piles with only minor framestone patches preserved. An exception to this rule is represented by the high-energy, coral-‘algal’ Ota Reef from the Kimmeridgian of the Lusitanian Basin (Portugal). The narrow Ota Reef tract rims a small intra-basinal carbonate platform exhibiting perfect facies zonation (from W to E: Reef tract, back reef sands, peritidal belt, low-energy shallow lagoon). The reef is dominated by massive corals (Thamnasteria, Microsolena, Stylina). Complete preservation of coral framework is rare: like other Upper Jurassic high-energy reefs, the Ota Reef is very rich in debris; however, this debris is largely stabilized by algal and microbial crusts, what contrasts the other examples and gives the Ota Reef the appearance of a typical modern high-energy coral-melobesioid algal reef. Further similarities to modern reefs are the likely existence of a spur-and-groove system, the perfect sheltering of inner platform areas and the occurrence of small islands, as indicated by local blackenings and early vadose and karstic features.  相似文献   

11.
Abstract

A therapeutic rationale is proposed by selectively targeting tyrosine kinase 2 (TYK 2) to obtain potent TYK 2 inhibitors by molecular modeling studies. In the present study, we have taken tyrosine kinase (TYK 2) inhibitors and carried out molecular docking, 3?D quantitative structure–activity relationship (3D-QSAR) analysis and molecular dynamics (MD). Based on the 3D-QSAR results thirteen new compounds (R-1 to R-13) were designed and synthesized in good yields. The synthesized molecules were evaluated for their in vitro anticancer activity against LnCap and A549 cell lines. The molecules R-1, R-3, R-5, R-7, and R-10 exhibited considerable anti cancer activity.  相似文献   

12.
We developed a new targeted cationic nanoparticulate system composed of poly(D,L-lactic-co-glycolic acid) (PLGA), 1,2-dioleoyl-3-(trimethylammonium) propane (DOTAP) and asialofetuin (AF), and found it to be a highly effective formulation for gene delivery to liver tumor cells. The nanoparticles (NP) were prepared by a modified solvent evaporation process that used two protocols in order to encapsulate (NP1 particles) or adsorb (NP2 particles) plasmid DNA. The final particles are in the nanoscale range. pDNA loaded in PLGA/DOTAP/AF particles with high loading efficiency showed a positive surface charge. Targeted asialofetuin-nanoparticles (AF-NP) carrying genes encoding for luciferase and interleukin-12 (IL-12) resulted in increased transfection efficiencies compared to free DNA and to plain (non-targeted) systems, even in the presence of 60% fetal bovine serum (FBS). The results of transfections performed on HeLa cells, defective in asialoglycoprotein receptors (ASGPr-), confirmed the receptor-mediated endocytosis mechanism. In summary, this is the first time that asialoglycoprotein receptor targeting by PLGA/DOTAP/DNA nanoparticles carrying the therapeutic gene IL-12 has been shown to be efficient in gene delivery to liver cancer cells in the presence of a very high concentration of serum, and this could be a potential system for in vivo application.  相似文献   

13.
Summary Two patch reefs which predominately consist of the oysterNanogyra nana (Sowerby 1822) are exposed in Lower Kimmeridigian strata of the Langenberg hillrange, central Germany. Left oyster valves making up the frame-work of the reefs formed small abundant cavities that were inhabited by a unique sponge community. The excellent preservation of non-rigid sponges was related to early organomineralization within the decaying sponge tissue. As a process of sponge taphonomy, different types of microbially induced carbonates precipitated preserving spicule aggregates. Organomineralization within sponge soft tissues is especially favored with the Langenberg patch reefs due to the closed or semi-closed system conditions with the cavities. The δ13C values ofin situ formed microbialities reveal that carbonate precipitation was in equilibrium with Jurassic seawater. The carbon of the microbialites does not derive from the bacterial remineralization of organic matter, but is of a marine source. Likewise, organomineralization is probably related to bacterial EPS or decaying sponge tissues providing an organic matrix for initial carbonate precipitation. Biomarker analyses revealed, that the patch reef microbialites contain terminally branched fatty acids (iso-andanteiso-pentadecanoic acid) in significant concentrations. These fatty acids, like hopanoid hydrocarbons, are most likely of a bacterial source. This is in agreement with sulfate-reducing bacteria remineralizing the decaying sponges as further indicated by the occurrence of framboidal pyrite in sponge microbialites.  相似文献   

14.
Summary A rich and diverse dasycladalean algae association is described from the Upper Triassic succession of Mt. Rotonda (Calabria-Lucania border, Southern Italy). This association consists of:Neoteutloporella rajkae n.sp.,Griphoporella bechst?dti n.sp.,Physoporella zamparelliae n.sp.,Spinaporella andalusica Flügel & Flügel-Kahler, 1984,S.? granadaensis Flügel & Flügel-Kahler, 1984,Chinianella? sp.,Gyroporella sp.,Griphoporella? sp. andPhysoporella aff.leptotheca. Neoteutloporella rajkae n.sp. is characterised by an undulated calcareous skeleton with short acrophore primary laterals bearing a tuft of 4–6 elongate, segmented, trichophore secondary laterals. This species allows to extend back to the Upper Triassic the stratigraphic range of the genusNeoteutloporella, previously known only from Upper Jurassic levels. Griphoporella bechst?dti n.sp. has a cylindrical calcareous skeleton and primary laterals only, consisting of a thin proximal part followed by a swollen portion that pinches out distally and finally opens outward with a cup-like swelling. Physoporella zamparelliae n.sp. is characterised by a calcareous skeleton made by partly welded thin individual sheaths enclosing the laterals. The laterals are piriferous, vertically compressed, roughly triangular both in vertical and in verticillar section. In some specimens they end with a spine-like thin apophysis. This species confirms that the typical Middle Triassic genusPhysoporella survived up into the Norian. The dasycladalean algal association of the Norian of Mt. Rotonda shows some similarities with the algal association found in the Upper Triassic of the Betic Cordillera whereas it is markedly different from the rich association occurring in the Upper Triassic of Sicily and of the Northern Calcareous Alps. This pattern is coupled with a different composition of the platform margin communities: microbial/serpulids bioconstructions in the Upper Triassic of the Calabria-Lucania border and of Alpujarridevs. Dachstein-type reefs in Sicily and the Northern Calcareous Alps. This indicates that the palaeoceanographic and palaeogeographic conditions controlled both the development of the different platform margin and of the different algal assemblages.  相似文献   

15.
Two new organotin(IV) complexes with dianionic dipeptides containing the α-aminoisobutyryl residue (Aib) as ligands are described. The solid complexes [(n-Bu)2Sn(H−1LA)] · 2MeOH (1 · 2MeOH) (LAH = H-Aib-L-Leu-OH) and [(n-Bu)2Sn(H−1LB)] · MeOH (2 · MeOH) (LBH = H-Aib-L-Ala-OH) have been isolated and characterized by single-crystal X-ray crystallography and spectroscopic techniques (H−1L2− is the dianionic form of the corresponding dipeptide). Complexes 1 · 2MeOH and 2 · MeOH are monomeric with similar molecular structures. The doubly deprotonated dipeptide behaves as a N(amino), N(peptide), O(carboxylate) ligand and binds to the SnIV atom. The five-coordinate metal ion has a distorted trigonal bipyramidal geometry. A different network of intermolecular hydrogen bonds in each compound results in very dissimilar supramolecular features. The IR, far-IR, Raman and 119Sn NMR data are discussed in terms of the nature of bonding and known structures. The antibacterial and antiproliferative activities as well as the effect of the new compounds on pDNA were examined. Complexes 1 and 2 are active against the gram-positive bacteria Bacillus subtilis and Bacillus cereus. The IC50 values reveal that the two compounds express promising cytotoxic activity in vitro against a series of cell lines.  相似文献   

16.
- Preamble. This series of two papers analyses and compares the environmental loads of different water production technologies in order to establish, in a global, rigorous and objective way, the less aggressive technology for the environment with the present state of the art of the technology. Further, it is also presented an estimation of the potential environmental loads that the considered technologies could provoke in future, taking into account the most suitable evolution of the technology. - Part 1 presents the assessment of most commercial desalination technologies which are spread worldwide: Reverse Osmosis, Multi Effect Desalination and Multi Stage Flash. Part 2 presents the comparative LCA analysis of a big hydraulic infrastructure, as is to be found in the Ebro River Water Transfer project, with respect to desalination. - DOI: http://dx.doi.org/10.1065/lca2004.09.179.1 - Intention, Goal and Background. In this paper, some relevant results of a research work are presented, the main aim of which consists of performing the environmental assessment of different water production technologies in order to establish, in a global, rigorous and objective way, the less aggressive technology for the environment of potable water supply to the end users. That is, the scope of this paper is mostly oriented to the comparative Life Cycle Assessment of different water production technologies instead of presenting new advancements in the LCA methodology. In Part 1, the environmental loads associated with the most widespread and important commercial desalination technologies all over the world - Reverse Osmosis (RO), Multi Effect Desalination (MED) and Multi Stage Flash (MSF) – are compared. The assessment technique is the Life Cycle Analysis (LCA), which includes the entire life cycle of each technology, encompassing: extraction and processing raw materials, manufacturing, transportation and distribution, operation and final waste disposal.- Methods and Main Features. The software SimaPro 5.0, developed by Dutch PRé Consultants, has been used as the analysis tool, because it is a well known, internationally accepted and validated tool. Different evaluation methods have been applied in the LCA evaluation: CML 2 baseline 2000, Eco-Points 97 and Eco-Indicator 99. Data used in the inventory analysis of this Part 1 come from: a) existing plants in operation; b) data bases implemented in the SimaPro 5.0 software -BUWAL 250, ETH-ESU 96, IDEMAT 2001. Different scenarios have been analyzed in both parts in order to estimate, not only the potential of reduction of the provoked environmental loads with the present state of the art of technology, but also the most likely future trend of technological evolution. In Part 1, different energy production models and the integration of desalination with other productive processes are studied, while the effect of the most likely technological evolution in the midterm, and the estimation of the environmental loads to the water transfer during drought periods are considered in Part 2. Results and Discussion The main contribution to the global environmental impact of desalination technologies comes from the operation, while the other phases, construction and disposal, are almost negligible when compared to it. Energy is very important in desalination, for this reason the environmental loads change a lot depending on the technology used for providing the energy used in the desalination process. Among the different analyzed technologies, RO is the least aggressive desalination technology (one order of magnitude lower than the thermal processes, MSF and MED) for the environment. When integrating thermal desalination with other productive processes taking advantage of the residual heat, the environmental loads of thermal desalination technologies is highly reduced, obtaining similar loads to that of RO. The environmental loads of desalination technologies are significantly reduced when an energy model based on renewable energies is used. Taking into account the technological evolution, which is experiencing the RO, a reduction of its environmental load by about 40% is to be expected in the mid-term. Conclusion The main conclusion of Part 1 is that, with the present state of the art of the technology, RO is clearly the desalination technology with a reduced environmental load (one order of magnitude lower than the thermal processes, MSF and MED). In the case of thermal desalination technologies, their environmental load can be highly reduced (about 1,000 times less) when integrated with other industrial processes. In the case of RO, the scores and the airborne emissions obtained from an electricity production model based on renewable energies are about 65-70 times lower than those obtained when the electricity production model is mainly based on fossil fuels. Recommendations and Outlook Although desalination technologies are energy intensive and provoke an important environmental load, they present a high potential in being reduced since: a) in the mid-term, it is to be expected that the different technologies could improve their efficiency significantly, b) the environmental loads would be highly reduced if the energy production models were not mainly based on fossil fuels and c) the energy consumption, particularly in the case of thermal desalination, can be drastically reduced when integrating desalination with other productive processes. The results presented in this paper indicate that a very interesting and promising field of research is available in order to reduce the environmental load of these vigorous and increasing desalination technologies.  相似文献   

17.
Summary At Collades de Bastus, Catalonian Pyrences, a Santonian mixed siliciclastic-carbonate succession indicates two proximal-distal gradients, and records two styles of stratigraphical development upon relative sea-level change. The succession consists of four small-scale sequences (5.1 to 5.4) within the highstand systems tract of the. “Valicarca-5” depositional sequence of Simo (1993), and is topped by a drowning sequence (small-scale sequence 5.5). The investigated succession (Collades Member) accumulated near the margin of the south-Pyrenean shelf, shortly before development of the south-vergent Boixols thrust system. Deposition of the Collades Member commenced with moderate sea-level rise accompanied by increased siliciclastic input. In the larger, eastern outcrop sector the Collades Member consists of a succession of neritic marls with four intercalated intervals each deposited from a carbonate shelf. Each carbonate interval consists of stacked upward-shoaling cycles interpreted as parasequences. From bottom to top, most parasequences consist of a coral-sponge-rudist bioconstruction, a rudist biostrome, and bioclastic limestones. Depositional sequences 5.1 to 5.4 developed by overstep of shelf carbonates with neritic marls, corresponding to the transgressive systems tract (TST) and to part of the highstand systems tract(HST) The carbonate facies tract of the HST consists of stacked parasequences that become thinner up-section and record a westward component of progradation. Each highstand carbonate interval is overlain by a stack of carbonate parasequences that become thicker up-section and, down depositional dip, by neritic marls. Together, the upward-thickening parasequence stack and the laterally adjacent overlying succession of neritic marls comprise the TST and part of the HST of the successive sequence. The sequence boundary is the level of maximum shoaling within each carbonate shelf interval. The uppermost sequence 5.5 is a drowning sequence (cf. Simo 1993). In the western outcrop sector, the Collades Member consists of hummocky cross-laminated to bioturbated sandy calcarenites, of neritic marls and of relatively thin intervals of coral-sponge-rudist limestones. Sequence development may have started with deposition of sharp-based bedsets of sandy calcarenites that both eastward and up-section become thinner and grade into neritic marls. Together, the succession of sandy calcarenites and neritic marls may comprise the TST and, possibly, part of the HST. In the HST neritic marls and, locally, coral-sponge-rudist bioconstructions accumulated. Deposition of some calcarenite bedsets seems to have started near or closely after maximum progradation of each carbonate shelf in the eastern part of outcrop. The stratigraphic architecture of the Collades Member indicates, for the eastern outcrop sector, an east-west proximal-distal gradient, whereas the western sector records a west-east gradient. The opposite gradients result from outcrop intersection subparallel to oblique to general northward depositional dip, across two distinct shelf depositional systems.  相似文献   

18.
A new, phylogenetically distinct, dissimilatory, Fe(III)-reducing bacterium was isolated from surface sediment of a hydrocarbon-contaminated ditch. The isolate, designated strain PAL-1, was an obligately anaerobic, non-fermentative, motile, gram-negative vibrio. PAL-1 grew in a defined medium with acetate as electron donor and ferric pyrophosphate, ferric oxyhydroxide, ferric citrate, Co(III)-EDTA, or elemental sulfur as sole electron acceptor. PAL-1 also used proline, hydrogen, lactate, propionate, succinate, fumarate, pyruvate, or yeast extract as electron donors for Fe(III) reduction. It is the first bacterium known to couple the oxidation of an amino acid to Fe(III) reduction. PAl-1 did not reduce oxygen, Mn(IV), U(VI), Cr(VI), nitrate, sulfate, sulfite, or thiosulfate with acetate as the electron donor. Cell suspensions of PAL-1 exhibited dithionite-reduced minus air-oxidized difference spectra that were characteristic of c-type cytochromes. Analysis of the 16S rRNA gene sequence of PAL-1 showed that the strain is not related to any of the described metal-reducing bacteria in the Proteobacteria and, together with Flexistipes sinusarabici, forms a separate line of descent within the Bacteria. Phenotypically and phylogenetically, strain PAl-1 differs from all other described bacteria, and represents the type strain of a new genus and species, Geovibrio ferrireducens. Received: 26 September 1995 / Accepted: 28 February 1996  相似文献   

19.
Summary The marine Paleogene of the Tremp Basin in the Central Southern Pyrenees corresponds to four depositional sequences which are related to global eustatic third order cycles (Tejas A 2.3–2.6). Associated transgressive and downlap surfaces coincide with boundaries of biozones. Lowstand systems tracts consist of estuarine and braid delta systems. Transgressive and highstand systems tracts are composed of carbonate banks and reefs. Slow thrust-induced changes of the basin topography conditioned the basic type and the areal distribution of carbonate highstand and clastic lowstand systems. Rapid relative sea level changes controlled the activity and internal dynamic of the depositional systems. E-W directed blind thrust anticlines are covered during highstand periods by carbonate fringing banks withNummulites bars. N-S orientation of thrust anticlines leads to the evolution of reef-dominated barrier banks and shelf lagoonal homoclinal ramps. On-bank transport of carbonate sands dominates during transgressions, off-bank transport during highstand periods. Continuous thrusting during the Ilerdian caused angular unconformities only in combination with relative sea level fall. Sequence-internal onlap configurations result from contemporaneous tectonic tilting. Fourth order carbonate bank margin cycles contain well developed lowstand tracts due to increased subsidence rates. Fourth order flooding surfaces are marked by paleosoil horizons at their landward continuation.  相似文献   

20.
The 193-kD vault protein, VPARP, is a novel poly(ADP-ribose) polymerase.   总被引:21,自引:0,他引:21  
Mammalian vaults are ribonucleoprotein (RNP) complexes, composed of a small ribonucleic acid and three proteins of 100, 193, and 240 kD in size. The 100-kD major vault protein (MVP) accounts for >70% of the particle mass. We have identified the 193-kD vault protein by its interaction with the MVP in a yeast two-hybrid screen and confirmed its identity by peptide sequence analysis. Analysis of the protein sequence revealed a region of approximately 350 amino acids that shares 28% identity with the catalytic domain of poly(ADP-ribose) polymerase (PARP). PARP is a nuclear protein that catalyzes the formation of ADP-ribose polymers in response to DNA damage. The catalytic domain of p193 was expressed and purified from bacterial extracts. Like PARP, this domain is capable of catalyzing a poly(ADP-ribosyl)ation reaction; thus, the 193-kD protein is a new PARP. Purified vaults also contain the poly(ADP-ribosyl)ation activity, indicating that the assembled particle retains enzymatic activity. Furthermore, we show that one substrate for this vault-associated PARP activity is the MVP. Immunofluorescence and biochemical data reveal that p193 protein is not entirely associated with the vault particle, suggesting that it may interact with other protein(s). A portion of p193 is nuclear and localizes to the mitotic spindle.  相似文献   

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