966 resultados para (7)Li MRI
Resumo:
M r = 188.22, monoclinic, P21/n, a = 6.219 (2), b= 10.508 (2), c=7.339 (1)A, t= 107.64 (2) °, V= 457 ,/k 3, Z = 2, D m - - 1.360 (3), D x = 1.366 (2)Mgm -3, ~,(MoKa) = 0.7107/~, #= 0.053 mm -I, F(000) = 200, T= 293 K. Final R = 5.8% for 614 significant reflections. The molecule, which does not possess a centre of symmetry, occupies a crystallographic centre of symmetry because of the statistical enantiomeric and rotational disorder. Latticeenergy calculations, based on van der Waals attractive and repulsive potentials, clearly show minima at the observed disordered positions.
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The repeat unit of the K12 capsular polysaccharide isolated from the Acinetobacter baumannii global clone 1 clinical isolate, D36, was elucidated by means of chemical and spectroscopical methods. The structure was shown to contain N-acetyl-D-galactosamine (D-GalpNAc), N-acetyl-D-fucosamine and N-acetyl-L-fucosamine linked together in the main chain, with the novel sugar, 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-altro-non-2-ulosonic acid (5,7-di-N-acetylacinetaminic acid or Aci5Ac7Ac), attached to D-GalpNAc as a side branch. This matched the sugar composition of the K12 capsule and the genetic content of the KL12 capsule gene cluster reported previously. D-FucpNAc was predicted to be the substrate for the initiating transferase, ItrB3, with the Wzy polymerase making a α-D-FucpNAc-(1 → 3)-D-GalpNAc linkage between the repeat units. The three glycosyltransferases encoded by KL12 are all retaining glycosyltransferases and were predicted to form specific linkages between the sugars in the K12 repeat unit.
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Regional metamorphic belts provide important constraints on the plate tectonic architecture of orogens. We report here a detailed petrologic examination of the sapphirine-bearing ultra-high temperature (UHT) granulites from the Jining Complex within the Khondalite Belt of the North China Craton (NCC). These granulites carry diagnostic UHT assemblages and their microstructures provide robust evidence to trace the prograde, peak and retrograde metamorphic evolution. The P–T conditions of the granulites estimated from XMgGrt(Mg/Fe + Mg) − XMgSpr isopleth calculations indicate temperature above 970 °C and pressures close to 7 kbar. We present phase diagrams based on thermodynamic computations to evaluate the mineral assemblages and microstructures and trace the metamorphic trajectory of the rocks. The evolution from Spl–Qtz–Ilm–Crd–Grt–Sil to Spr–Qtz–Crd–Opx–Ilm marks the prograde stage. The Spl–Qtz assemblage appears on the low-pressure side of the P–T space with Spr–Qtz stable at the high-pressure side, possibly representing an increase in pressure corresponding to compression. The spectacular development of sapphirine rims around spinel enclosed in quartz supports this inference. An evaluation of the key UHT assemblages based on model proportion calculation suggests a counterclockwise P–T path. With few exceptions, granulite-facies rocks developed along collisional metamorphic zones have generally been characterized by clockwise exhumation trajectories. Recent evaluation of the P–T paths of metamorphic rocks developed within collisional orogens indicates that in many cases the exhumation trajectories follow the model subduction geotherm, in accordance with a tectonic model in which the metamorphic rocks are subducted and exhumed along a plate boundary. The timing of UHT metamorphism in the NCC (c. 1.92 Ga) coincides with the assembly of the NCC within the Paleoproterozoic Columbia supercontinent, a process that would have involved subduction of passive margins sediments and closure of the intervening ocean. Thus, the counterclockwise P–T path obtained in this study correlates well with a tectonic model involving subduction and final collisional suturing, with the UHT granulites representing the core of the hot or ultra-hot orogen developed during Columbia amalgamation.
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The asymmetric unit of the title compound, C17H14O4, contains two independent molecules which differ in the relative orientations of the phenyl rings with repect to the essentially planar [maximum deviations of 0.029 (2) and 0.050 (2) angstrom in the two molecules] chromene fused-ring system, forming dihedral angles of 10.3 (5) and 30.86 (5)degrees in the two molecules. The crystal structure is stabilized by weak C-H center dot center dot center dot O and C-H center dot center dot center dot pi interactions, and pi-pi stacking interactions.
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Sensaatiolehden teksti, joka koostuu monista kuvallisista ja kielellisistä elementeistä, on tutkielman aiheena. Tutkielmassa vastataan kysymykseen, millainen tämä teksti on, kun sitä tarkastellaan multisemioottisesti. Analyysin lähtökohdaksi otetaan neljä merkityksen muodostumisen tasoa: tekstin rakentuminen (kompositio), maailman hahmottaminen (ideationaalinen merkitys), maailmaan osallistuminen (interpersoonainen merkitys) ja intertekstuaalisuus ynnä oletuslukijat (rekontekstualisointi). Teksti toimii yhtaikaa jokaisella tasolla. Aineistona on 7 päivää -lehden aukeama, jossa on Pop-palat-palsta. Aineistoa lähestytään deskriptiivisesti, eikä sitä arvoteta hyväksi tai huonoksi. Tutkielmassa käytetään viitekehyksinä systeemis-funktionaalista kieliteoriaa, kriittistä tekstianalyysiä ja sosiosemioottista visuaalista teoriaa. Tutkielma kuuluu tekstintutkimuksen alaan. Tekstiksi luetaan tässä työssä sekä visuaalisten että verbaalisten semioottisten merkkijärjestelmien tuotokset. Analyysissä osoitetaan, millaisen kokonaisuuden kuva ja kieli muodostavat, miten ne pelaavat yhteen ja millaista merkitystä yhteispeli viestii. Aikaisemman suomalaisen multisemioottisen tekstintutkimuksen kohteeksi ei ole otettu aikakauslehtiä saati sensaatiolehtiä. Elementtien muodostama kokonaisuus mahdollistaa lukijalle monta eri reittiä edetä tekstissä; teksti on multilineaarinen. Tärkeimmiksi elementeiksi erottuvat valokuvat ja otsikot. Sekä kuvassa että otsikossa, juttutekstissä ja kuvatekstissä etualaistetaan sama henkilö. Etualaistettu henkilö esitetään usein valokuvassa kahden henkilön välillä aktiivisena toimijana, hän on otsikossa tekijä sekä juttutekstissä ja kuvatekstissä teema. Osa otsikoista on puhekuplassa, ja muutenkin otsikoissa on vallalla verbaalinen prosessityyppi. Kuvan henkilöt puhuvat suoraan lukijalle. Referaattiotsikoiden totuudellisuus on otettu aukeamalla rennosti. Tätä selitetään moniäänisyyden käsitteellä: kuvan henkilön ja palstan kirjoittajan äänet kuuluvat otsikoissa samanaikaisesti. Tärkeä tutkimustulos on se, että otsikoita ei ole merkitty referoinniksi tyypillisten referointikonventioiden tapaan, vaan johtolauseen paikan ja tehtävän täyttää valokuva. Kuva kehystää referaattiotsikon. Lukijaan otetaan läheinen kontakti: häntä pyydetään vastaamaan viikkokilpailuun, kuvien henkilöt vaativat katseellaan lukijaa osallistumaan, valokuvat on rajattu sosiaalisti läheisiksi, käytetään arkikieltä. Aineistoteksti on ennen kaikkea sosiaalista. Analyysissä osoitetaan tekstin tehtäviä, joita ovat sosiaalisuuden lisäksi mm. kaupallisuus, viihteellisyys ja juoruilu. Tekstipiirteistä erityisesti kirjasinlajit ja -leikkaukset nähdään interteksteinä muihin aikakauslehtiin. Aukeaman kokonaisuus tulkitaan analogiseksi kollaasitaiteen kanssa. Räväkät kuvat ja otsikot yhdessä juttu- ja kuvatekstien ym. elementtien kanssa muodostavat multisemioottisen kokonaisuuden, jossa koodien perinteiset tehtävät sekoittuvat: visuaalinen on myös verbaalista ja verbaalinen visuaalista.
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Associations between injury and muscle asymmetries, as determined with magnetic resonance (MR) imaging, have been investigated in a number of sports medicine-based studies. For interventional or prospective studies into musculoskeletal injuries, it is important to determine the repeatability of the morphometric procedures used for quantifying muscle asymmetries. This study examines the intra-observer repeatability of manual segmentation for determining bilateral volumes of the individual hamstring muscles.
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This paper presents a validation study on the application of a novel interslice interpolation technique for musculoskeletal structure segmentation of articulated joints and muscles on human magnetic resonance imaging data. The interpolation technique is based on morphological shape-based interpolation combined with intensity based voxel classification. Shape-based interpolation in the absence of the original intensity image has been investigated intensively. However, in some applications of medical image analysis, the intensity image of the slice to be interpolated is available. For example, when manual segmentation is conducted on selected slices, the segmentation on those unselected slices can be obtained by interpolation. We proposed a two- step interpolation method to utilize both the shape information in the manual segmentation and local intensity information in the image. The method was tested on segmentations of knee, hip and shoulder joint bones and hamstring muscles. The results were compared with two existing interpolation methods. Based on the calculated Dice similarity coefficient and normalized error rate, the proposed method outperformed the other two methods.
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Background: Molecular marker technologies are undergoing a transition from largely serial assays measuring DNA fragment sizes to hybridization-based technologies with high multiplexing levels. Diversity Arrays Technology (DArT) is a hybridization-based technology that is increasingly being adopted by barley researchers. There is a need to integrate the information generated by DArT with previous data produced with gel-based marker technologies. The goal of this study was to build a high-density consensus linkage map from the combined datasets of ten populations, most of which were simultaneously typed with DArT and Simple Sequence Repeat (SSR), Restriction Enzyme Fragment Polymorphism (RFLP) and/or Sequence Tagged Site (STS) markers. Results: The consensus map, built using a combination of JoinMap 3.0 software and several purpose-built perl scripts, comprised 2,935 loci (2,085 DArT, 850 other loci) and spanned 1,161 cM. It contained a total of 1,629 'bins' (unique loci), with an average inter-bin distance of 0.7 ± 1.0 cM (median = 0.3 cM). More than 98% of the map could be covered with a single DArT assay. The arrangement of loci was very similar to, and almost as optimal as, the arrangement of loci in component maps built for individual populations. The locus order of a synthetic map derived from merging the component maps without considering the segregation data was only slightly inferior. The distribution of loci along chromosomes indicated centromeric suppression of recombination in all chromosomes except 5H. DArT markers appeared to have a moderate tendency toward hypomethylated, gene-rich regions in distal chromosome areas. On the average, 14 ± 9 DArT loci were identified within 5 cM on either side of SSR, RFLP or STS loci previously identified as linked to agricultural traits. Conclusion: Our barley consensus map provides a framework for transferring genetic information between different marker systems and for deploying DArT markers in molecular breeding schemes. The study also highlights the need for improved software for building consensus maps from high-density segregation data of multiple populations.
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The tomato I-3 gene introgressed from the Lycopersicon pennellii accession LA716 confers resistance to race 3 of the fusarium wilt pathogen Fusarium oxysporum f. sp. lycopersici. We have improved the high-resolution map of the I-3 region of tomato chromosome 7 with the development and mapping of 31 new PCR-based markers. Recombinants recovered from L. esculentum cv. M82 × IL7-2 F2 and (IL7-2 × IL7-4) × M82 TC1F2 mapping populations, together with recombinants recovered from a previous M82 × IL7-3 F2 mapping population, were used to position these markers. A significantly higher recombination frequency was observed in the (IL7-2 × IL7-4) × M82 TC1F2 mapping population based on a reconstituted L. pennellii chromosome 7 compared to the other two mapping populations based on smaller segments of L. pennellii chromosome 7. A BAC contig consisting of L. esculentum cv. Heinz 1706 BACs covering the I-3 region has also been established. The new high-resolution map places the I-3 gene within a 0.38 cM interval between the molecular markers RGA332 and bP23/gPT with an estimated physical size of 50-60 kb. The I-3 region was found to display almost continuous microsynteny with grape chromosome 12 but interspersed microsynteny with Arabidopsis thaliana chromosomes 1, 2 and 3. An S-receptor-like kinase gene family present in the I-3 region of tomato chromosome 7 was found to be present in the microsyntenous region of grape chromosome 12 but was absent altogether from the A. thaliana genome.
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Abstract is not available.
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Among the various substituted coumarins investigated only 7-acetoxycoumarin is observed to photodimerize topochemically in the crystalline state and this observation may be of importance in the context of "crystal engineering".
Resumo:
C17H2602, M, = 262, triclinic, PI, a = 8.513(2), b = 8.970(2), c = 11.741(3)A, a = 120.51 (5), fl = 93.30(4), y = 68.43(4) ° , V = 708.9,/k 3, Z = 2, D O = 1.213, D e = 1.227 Mg m -a, g(Mo Ka, 2 = 0.7107 ,&) = 0.084 mm -1, F(000) = 288. The structure, solved by direct methods, has been refined to an R value of 5.9% using 1361 intensity measurements. The ring junctions, in sequence from either end of the polycycle, are cis, trans and cis.
Resumo:
X-ray crystal structure analysis of 7-methoxycoumarin reveals that the reactive double bonds are rotated by about 65° with respect to each other, the centre-to-centre distance between the double bonds being 3.83 Å. In spite of this unfavourable arrangement, photodimerization occurs in the crystalline state yielding the syn-head-tail dimer as the only product. Lattice energy calculations on ground-state molecules in crystals throw light on the mechanism of the reaction.
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This research is based on the problems in secondary school algebra I have noticed in my own work as a teacher of mathematics. Algebra does not touch the pupil, it remains knowledge that is not used or tested. Furthermore the performance level in algebra is quite low. This study presents a model for 7th grade algebra instruction in order to make algebra more natural and useful to students. I refer to the instruction model as the Idea-based Algebra (IDEAA). The basic ideas of this IDEAA model are 1) to combine children's own informal mathematics with scientific mathematics ("math math") and 2) to structure algebra content as a "map of big ideas", not as a traditional sequence of powers, polynomials, equations, and word problems. This research project is a kind of design process or design research. As such, this project has three, intertwined goals: research, design and pedagogical practice. I also assume three roles. As a researcher, I want to learn about learning and school algebra, its problems and possibilities. As a designer, I use research in the intervention to develop a shared artefact, the instruction model. In addition, I want to improve the practice through intervention and research. A design research like this is quite challenging. Its goals and means are intertwined and change in the research process. Theory emerges from the inquiry; it is not given a priori. The aim to improve instruction is normative, as one should take into account what "good" means in school algebra. An important part of my study is to work out these paradigmatic questions. The result of the study is threefold. The main result is the instruction model designed in the study. The second result is the theory that is developed of the teaching, learning and algebra. The third result is knowledge of the design process. The instruction model (IDEAA) is connected to four main features of good algebra education: 1) the situationality of learning, 2) learning as knowledge building, in which natural language and intuitive thinking work as "intermediaries", 3) the emergence and diversity of algebra, and 4) the development of high performance skills at any stage of instruction.
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Finnish education politics presume that basic education should be equal to all students. While organising craft education equality can be understood as similarity or as possibility to choose. The possibility to be able to choose whether textile or technical craft despite of one´s gender has been the aim of laws and curriculums already over 30 years. In practice it´s almost impossible to students to ignore feminine and masculine roles that go deep into our culture. Choosing craft has been divided by gender, which is the reason why possibility to choose has not been good enough to educationalists of equality. The latest guidelines for the National core curriculum for bacis education were issued in 2004. According to curriculum craft education consists parts of both technical and textile craft. All students should take part in both sectors of crafts. Furthermore, one can be given a possibility to consentrate his studies in whether textile or technical craft. The curriculum does not set the rules how the education should be organised, which means that it can be organised in many ways depending on city, school or teacher. Teachers and other specialists have contradictory feelings towards shared craft education, because traditional way to see craft in Finland is to separate textile craft from technical craft. Both crafts have some common features that are introduced in curriculum. Besides there is many equal things in craft theories that bind textile and technical craft to each other. The main purpose of this research was to find out, how shared craft education has been organised at the 7.th grade in Finnish comprehensive school, and which things affect in the settlements. Second goal was to describe and compare teachers´ experiences in teaching shared craft education. Third aim of this study was how shared craft has changed craft education. I collected the research material in May 2006 by interviewing both textile and technical craft teachers who teach shared craft. The material consists of fourteen theme interviews. In the analysis of the material I used theoretic bounded document analysis. According to the research there are three different ways to organise shared craft education: 50 50-arrangement, exchanging period and project week. In the schools that carried out 50 50-arrangement teaching was realised mainly in heterogenous groups. Principals had usual a lot of authorization on how to arrange craft education, which means that their views on equality, laws and curriculum affected in the settlemets more than teachers´ opinions. Teachers´ attitudes to shared craft were mainly positive. The changing of craft education can be divided in two parts: the aims and the containings of the curriculum have changed, as well as the meaning of the craft as core subject. Teachers have been forced to decrease the containings of both textile and technical crafts. Despite of eliminations both crafts still have comprehensive containings. Teachers decided what to teach by these argumets: Students should learn some basic things or produce a certain product. Usually teachers had also a lot of experience and special intrests in crafts. According to this research there is four significant meanings for shared craft education: 1) developing readiness for doing things, 2) developing skills of thinking, 3) delight of doing things and 4) teaching attitude.