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Sequence Consisting (sequence + consisting)
Selected AbstractsA Domino Sequence Consisting of Insertion, Coupling, Isomerization, and Diels,Alder Steps Yields Highly Fluorescent Spirocycles (III) and (V).CHEMINFORM, Issue 16 2005Daniel M. D'Souza No abstract is available for this article. [source] Modulation of spinal inhibitory reflex responses to cutaneous nociceptive stimuli during upper limb movementEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2008Romildo Don Abstract In the present study we investigated the probability, latency and duration of the inhibitory component of the withdrawal reflex elicited by painful electrical stimulation of the index finger in humans. The stimulus consisted of a train of high-intensity pulses. The investigation was carried out in several upper limb muscles during isometric contractions of different strengths and during a motor sequence consisting of reaching, picking up and transporting an object. We used a new algorithm to detect and characterize the inhibitory reflex. The reflex was found in all muscles except the brachioradialis at all the isometric contraction strengths, and showed a distal-to-proximal gradient of latency and duration. Conversely, during movement the reflex probability was high (> 80%) in the anterior deltoid and triceps muscles during reaching, in the extensor carpi radialis muscle during transporting of the object, and in the first interosseous muscle during both picking up and transporting of the object. This modulation of inhibitory reflex transmission in the upper limb muscles suggests that the motor response is organized in such a way as to inhibit the overall ongoing motor task by interrupting motion during reaching and by releasing the object during transporting. This pattern of modulation appears to differ markedly from that previously reported for the excitatory component of the withdrawal reflex. Study of the nociceptive inhibitory reflexes during movement offers new and more profound insights into the functional anatomical organization of the spinal interneuronal network mediating sensory,motor integration. [source] 3-Tocopherylisoxazolines by [2+3] CycloadditionEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2004Thomas Rosenau Abstract New isoxazoline derivatives of ,-tocopherol (1), the main component of vitamin E, were synthesized in a facile, two-step sequence consisting of nitration followed by 1,3-dipolar cycloaddition. 5-Nitromethyl-,-tocopheryl acetate (3), obtained from the cheap ,-tocopheryl acetate (2) by direct nitration in one step, acted as the nitrile oxide precursor in the reaction with various alkenes. The facile conversion proceeded in the presence of equimolar amounts of PhNCO and catalytic amounts of triethylamine. The NMR spectra of the product isoxazolines 5,13, showing strongly temperature-dependent resonances of the 4,,-CH, 4-CH2 and the acetyl group, are discussed, and the crystal structures of model compounds containing a methyl group instead of the isoprenoid side chain are presented. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Palladium-Catalyzed Sequential Reactions via Allene Intermediates for the Rapid Synthesis of Fused Polycyclic Pyrrole DerivativesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 18 2009Xian Huang Abstract In this paper, we report a novel sequential reaction sequence consisting of a series of processes including Sonogashira coupling, propargyl-allenyl isomerization, [3+2],cycloaddition, denitrogenation, and highly selective biradical coupling reaction, providing an efficient synthesis of fused polycyclic pyrrole derivatives. The reaction features one CC bond and two CN bonds formed to construct the pyrrole unit, together with two rings efficiently assembled in one stroke. [source] Characterization of the porcine Kisspeptins receptor gene and evaluation as candidate for timing of puberty in sowsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 4 2008S. Li Summary Kisspeptins receptor (KISS1R), also called GPR54, is a key regulator of puberty in many species. KISS1R and its genetics in pigs remain unexplored. The objective of this study was to characterize the porcine KISS1R gene and evaluate the association of KISS1R mutations with age at puberty in sows. KISS1R was assigned to pig chromosome 2q21-24 by radiation hybrid mapping. It has a 1438 bp full-length cDNA and spans 3349 bp genomic sequence consisting of five exons and four introns. Semi-quantitative RT-PCR showed that KISS1R transcripts was particularly abundant in the adrenal, prostate, testis, thymus, pituary and hypothalamus. KISS1R mRNA content in the hypothalamus was determined by real-time quantitative RT-PCR, and it fluctuated during the oestrous cycle with the highest level in the luteal phase. Anoestrus sows had markedly lower hypothalamic KISS1R mRNA content than cyclic animals. Seven KISS1R SNPs were identified in the founder animals of a White Duroc × Erhualian intercross. One missense mutation (T/C245) showed quite different allele distribution in Chinese and Western breeds. All F0, F1 animals and 367 detailed phenotyped cyclic F2 sows in the White Duroc × Erhualian intercross were genotyped for three KISS1R polymorphisms. No significant association of KISS1R haplotypes and haplotype pairs with age at puberty was observed in the resource population, indicating that mutations in KISS1R are not responsible for divergent age at puberty in White Duroc and Erhualian pigs. [source] Synthesis of 2,4-diaminopyrido[2,3- d]pyrimidines and 2,4-diamino-quinazolines with bulky dibenz[b,f]azepine and dibenzo[a,d]-cycloheptene substituents at the 6-position as inhibitors of dihydrofolate reductases from pneumocystis carinii, toxoplasma gondii, and mycobacterium avium,JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2000Andre Rosowsky The synthesis of four previously undescribed 2,4-diaminopyrido[2,3- d]pyrimidines (3,4) and 2,4-diaminoquinazolines (5,6) with a bulky tricyclic aromatic group at the 6-position is described. Condensation of dibenz[b,f]azepine with 2,4-diamino-6-bromomethylpyrido[2,3- d]pyrimidine (8) and 2,4-diamino-6-bromomethylquinazoline (17) in the presence of sodium hydride afforded N -[(2,4-diaminopyrido[2,3- d]-pyrimidin-6-yl)methyl]dibenz[b,f]azepine (3) and N -[(2,4-diaminoquinazolin-6-yl)methyl]dibenz[b,f]-azepine (4), respectively. Condensation of 5-chlorodibenzo[a,d]cycloheptene (19) and 5-chloro-10,11-dihydrodibenzo[a,d]cycloheptene (20) with 2,4,6-triaminoquinazoline (13) afforded 5-[(2,4-diamino-quinazolin-6-yl)amino]-5H -dibenzo[a,d]cycloheptene (5) and the corresponding 10,11-dihydro derivative (6), respectively. The bromides 8 and 17, as hydrobromic acid salts, were obtained from the corresponding nitriles according to a standard three-step sequence consisting of treatment with Raney nickel in formic acid followed by reduction with sodium borohydride and bromination with dry hydrogen bromide in glacial acetic acid. Compounds 3,6 were evaluated in vitro for the ability to inhibit dihydrofolate reductase from Pneumocystis carinii, Toxoplasma gondii, Mycobacterium avium, and rat liver. Compounds 3 and 4 were potent inhibitors of all four enzymes, with IC50 values in the 0.03,0.1 ,M range, whereas 5 was less potent. However the selectivity of all four compounds for the parasite enzymes relative to the rat enzyme was<10-fold, whereas the recently reported lead compound in this series, N -[(2,4-diaminopteridin-6-yl)methyl]dibenz[b,f]azepine (1) has > 100-fold selectivity for the T. gondii and M. avium enzyme and 21-fold selectivity for the P carinii enzyme. [source] Spatial variability of O layer thickness and humus forms under different pine beech,forest transformation stages in NE GermanyJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 1 2006Oliver Bens Abstract Spatial variability of humus layer (O layer) thicknesses can have important impacts upon soil water dynamics, nutrient storage and availability, as well as plant growth. The purpose of the present study was to elucidate the impact of forest-transformation practices on the spatial variability of O layer thicknesses. The study focused on the Kahlenberg forest area (NE Germany) with stands of Scots pine (Pinus sylvestris) and European beech (Fagus sylvatica) of different age structures that form a transformation chronosequence from pure Scots pine stands towards pure European beech stands. Topsoil profiles including both, the O layer and the uppermost humic mineral soil horizon were excavated at intervals of 0.4 m along 15,20 m long transects, and spatial variability of O layer thicknesses was quantified by variogram analysis. The correlation lengths of total O layer thickness increased in the sequence consisting of pure pine stand (3.1 m) , older mixed stand (3.7 m) , pure beech stand (4.5 m), with the exception of the younger mixed stand, for which no correlation lengths of total O layer thickness could be determined. The degree of spatial correlation, i.e., the percentage of the total variance which can be described by variograms, was highest for the two monospecies stands, whereas this percentage was distinctly lower for the two mixed stands. A similar minimum for the two mixed stands was observed for the correlation lengths of the Oh horizon. These results suggest that the spatial structures of forest-transformation stands may be interpreted in terms of a disturbance (in the form of the underplanting of beech trees). After this disturbance, the forest ecosystem requires at least 100 y to again reach relative equilibrium. These findings are in line with the results of other soil-related investigations at these sites. Räumliche Variabilität der Humuslagenmächtigkeit und Humusformen in verschiedenen Stadien des Waldumbaus von Kiefer zu Buche in NO-Deutschland Die räumliche Variabilität der Humusauflagenmächtigkeit kann einen bedeutenden Einfluss auf die Bodenwasserdynamik, Nährstoffspeicherung und -verfügbarkeit sowie das Pflanzenwachstum haben. Ziel dieser Studie war es, die Auswirkungen von Waldumbaumaßnahmen auf die räumliche Verteilung der Auflagehumusmächtigkeiten zu untersuchen. Im Forstrevier Kahlenberg, mit Beständen von Kiefer (Pinus sylvestris) und Buche (Fagus sylvatica) unterschiedlichen Alters, welche eine Transformations-Chronosequenz von einem Kiefern-Reinbestand hin zu einem reinen Buchenbestand darstellen, wurden Humusprofile entlang von 15,20 m langen Transekten in Abständen von 0,4 m aufgenommen. Die räumliche Variabilität der Mächtigkeiten der Auflagehumushorizonte wurde durch Variogramm-Analysen quantifiziert. Die Korrelationslängen der Mächtigkeiten des gesamten Auflagehumus stiegen in der Reihenfolge reiner Kiefernbestand (3,1 m) , älterer Mischbestand (3,7 m) , reiner Buchenbestand (4,5 m) an. Aus dieser Reihe fällt der jüngere Mischbestand heraus; für ihn konnten keine Korrelationslängen ermittelt werden. Der Grad der räumlichen Korrelation, d. h. der Anteil der gesamten Varianz, der durch Variogramme beschrieben wird, ist für die beiden Reinbestände am höchsten, während er für die beiden Mischbestände deutlich geringer ist. Ein ähnliches Minimum für die beiden Mischbestände ergibt sich, wenn nur die Korrelationslängen der Oh-Mächtigkeiten betrachtet werden. Diese Ergebnisse deuten darauf hin, dass die räumlichen Strukturen von Waldumbaubeständen im Sinne einer Störung gedeutet werden können (wobei die Umbaumaßnahme und der Unterbau mit Buchen die Störung darstellt). Diese Störung dauert offenbar mindestens 100 a an. Dieser Befund stimmt mit den Ergebnissen aus Studien zu weiteren relevanten Bodeneigenschaften an Forststandorten im nordostdeutschen Tiefland überein. [source] Genome-wide SNP detection in the great tit Parus major using high throughput sequencingMOLECULAR ECOLOGY, Issue 2010NIKKIE E. M. VAN BERS Abstract Identifying genes that underlie ecological traits will open exiting possibilities to study gene,environment interactions in shaping phenotypes and in measuring natural selection on genes. Evolutionary ecology has been pursuing these objectives for decades, but they come into reach now that next generation sequencing technologies have dramatically lowered the costs to obtain the genomic sequence information that is currently lacking for most ecologically important species. Here we describe how we generated over 2 billion basepairs of novel sequence information for an ecological model species, the great tit Parus major. We used over 16 million short sequence reads for the de novo assembly of a reference sequence consisting of 550 000 contigs, covering 2.5% of the genome of the great tit. This reference sequence was used as the scaffold for mapping of the sequence reads, which allowed for the detection of over 20 000 novel single nucleotide polymorphisms. Contigs harbouring 4272 of the single nucleotide polymorphisms could be mapped to a unique location on the recently sequenced zebra finch genome. Of all the great tit contigs, significantly more were mapped to the microchromosomes than to the intermediate and the macrochromosomes of the zebra finch, indicating a higher overall level of sequence conservation on the microchromosomes than on the other types of chromosomes. The large number of great tit contigs that can be aligned to the zebra finch genome shows that this genome provides a valuable framework for large scale genetics, e.g. QTL mapping or whole genome association studies, in passerines. [source] Novel method for analyzing proteomeINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 6 2007Bo Liao Abstract We propose a 6D representation of protein sequences consisting of 20 amino acids. Based on this 6D representation, we propose a proteome distance measure for constructing phylogenic tree. And we make use of the corresponding similarity matrix to construct phylogenic tree. The examination of phylogenic tree belong to 30 mitochondrial sequence illustrates the utility of our approach. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [source] Orogenic Gold Mineralization in the Qolqoleh Deposit, Northwestern IranRESOURCE GEOLOGY, Issue 3 2007Farhang Aliyari Abstract The Qolqoleh gold deposit is located in the northwestern part of the Sanandai-Sirjan Zone, northwest of Iran. Gold mineralization in the Qolqoleh deposit is almost entirely confined to a series of steeply dipping ductile,brittle shear zones generated during Late Cretaceous,Tertiary continental collision between the Afro-Arabian and the Iranian microcontinent. The host rocks are Mesozoic volcano-sedimentary sequences consisting of felsic to mafic metavolcanics, which are metamorphosed to greenschist facies, sericite and chlorite schists. The gold orebodies were found within strong ductile deformation to late brittle deformation. Ore-controlling structure is NE,SW-trending oblique thrust with vergence toward south ductile,brittle shear zone. The highly strained host rocks show a combination of mylonitic and cataclastic microstructures, including crystal,plastic deformation and grain size reduction by recrystalization of quartz and mica. The gold orebodies are composed of Au-bearing highly deformed and altered mylonitic host rocks and cross-cutting Au- and sulfide-bearing quartz veins. Approximately half of the mineralization is in the form of dissemination in the mylonite and the remainder was clearly emplaced as a result of brittle deformation in quartz,sulfide microfractures, microveins and veins. Only low volumes of gold concentration was introduced during ductile deformation, whereas, during the evident brittle deformation phase, competence contrasts allowed fracturing to focus on the quartz,sericite domain boundaries of the mylonitic foliation, thus permitting the introduction of auriferous fluid to create disseminated and cross-cutting Au-quartz veins. According to mineral assemblages and alteration intensity, hydrothermal alteration could be divided into three zones: silicification and sulfidation zone (major ore body); sericite and carbonate alteration zone; and sericite,chlorite alteration zone that may be taken to imply wall-rock interaction with near neutral fluids (pH 5,6). Silicified and sulfide alteration zone is observed in the inner parts of alteration zones. High gold grades belong to silicified highly deformed mylonitic and ultramylonitic domains and silicified sulfide-bearing microveins. Based on paragenetic relationships, three main stages of mineralization are recognized in the Qolqoleh gold deposit. Stage I encompasses deposition of large volumes of milky quartz and pyrite. Stage II includes gray and buck quartz, pyrite and minor calcite, sphalerite, subordinate chalcopyrite and gold ores. Stage III consists of comb quartz and calcite, magnetite, sphalerite, chalcopyrite, arsenopyrite, pyrrhotite and gold ores. Studies on regional geology, ore geology and ore-forming stages have proved that the Qolqoleh deposit was formed in the compression,extension stage during the Late Cretaceous,Tertiary continental collision in a ductile,brittle shear zone, and is characterized by orogenic gold deposits. [source] | ||||||||||||||||