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101.
Boguslavskiy AE Mikosch J Gijsbertsen A Spanner M Patchkovskii S Gador N Vrakking MJ Stolow A 《Science (New York, N.Y.)》2012,335(6074):1336-1340
Subcycle strong-field ionization (SFI) underlies many emerging spectroscopic probes of atomic or molecular attosecond electronic dynamics. Extending methods such as attosecond high harmonic generation spectroscopy to complex polyatomic molecules requires an understanding of multielectronic excitations, already hinted at by theoretical modeling of experiments on atoms, diatomics, and triatomics. Here, we present a direct method which, independent of theory, experimentally probes the participation of multiple electronic continua in the SFI dynamics of polyatomic molecules. We use saturated (n-butane) and unsaturated (1,3-butadiene) linear hydrocarbons to show how subcycle SFI of polyatomics can be directly resolved into its distinct electronic-continuum channels by above-threshold ionization photoelectron spectroscopy. Our approach makes use of photoelectron-photofragment coincidences, suiting broad classes of polyatomic molecules. 相似文献
102.
103.
Knubben-Schweizer G Friedrich A Ebert U Hördemann M Hagen R Nuss K 《Tier?rztliche Praxis. Ausgabe G, Grosstiere/Nutztiere》2012,40(1):41-44
In a 7-week-old calf neurologic symptoms occurred after an accident in the feeding grid. The calf was alert but in left lateral recumbency. After having been placed on its right side it showed a sideward drift to the left. Following head movement, an asynchronous movement of the eyes could be observed. Lesions of the upper motor neuron system, N. vestibulocochlearis, Nn. oculomotorius, trochlearis and/or abducens as well as N. vagus were suspected. Radiological examination of the occipital region and cervical spine revealed an atlanto-occipital subluxation of the atlas. Based on all these findings, the diagnosis of traumatic atlanto-occipital dislocation was made and the calf was euthanized. The pathological findings confirmed this diagnosis. 相似文献
104.
KW Berendzen M Böhmer N Wallmeroth S Peter M Vesi Y Zhou FK Tiesler F Schleifenbaum K Harter 《Plant methods》2012,8(1):25-17
ABSTRACT: Understanding protein and gene function requires identifying interaction partners usingbiochemical, molecular or genetic tools. In plants, searching for novel protein-proteininteractions is limited to protein purification assays, heterologous in vivo systems such as the yeast-two-hybrid or mutant screens. Ideally one would be able to search for novel proteinpartners in living plant cells. We demonstrate that it is possible to screen for novel proteinproteininteractions from a random library in protoplasted Arabidopsis plant cells and recoversome of the interacting partners. Our screen is based on capturing the bi-molecularcomplementation of mYFP between an YN-bait fusion partner and a completely random preyYC-cDNA library with FACS. The candidate interactions were confirmed using in plantaBiFC assays and in planta FRET-FLIM assays. From this work, we show that the wellcharacterized protein Calcium Dependent Protein Kinase 3 (CPK3) interacts with APX3,HMGB5, ORP2A and a ricin B-related lectin domain containing protein At2g39050. This isone of the first random in planta screens to be successfully employed. 相似文献
105.
Wenxin Liu Tobias Würschum Hans P. Maurer Friedrich H. Longin Nicolas Ranc Hans P. Piepho Jochen C. Reif 《Plant Breeding》2013,132(1):99-106
Genomic selection (GS) is a promising alternative to marker‐assisted selection particularly for quantitative traits. In this study, we examined the prediction accuracy of genomic breeding values by using ridge regression best linear unbiased prediction in combination with fivefold cross‐validation based on empirical data of a commercial maize breeding programme. The empirical data is composed of 930 testcross progenies derived from 11 segregating families evaluated at six environments for grain yield and grain moisture. Accuracy to predict genomic breeding values was affected by the choice of the shrinkage parameter λ2, by unbalanced family size, by size of the training population and to a lower extent by the number of markers. Accuracy of genomic breeding values was high suggesting that the selection gain can be improved implementing GS in elite maize breeding programmes. 相似文献
106.
Niklas Bergknut Lucas A. Smolders Guy C.M. Grinwis Ragnvi Hagman Anne-Sofie Lagerstedt Herman A.W. Hazewinkel Marianna A. Tryfonidou Björn P. Meij 《Veterinary journal (London, England : 1997)》2013,195(3):282-291
Intervertebral disc (IVD) degeneration is common in dogs and can give rise to a number of diseases, such as IVD herniation, cervical spondylomyelopathy, and degenerative lumbosacral stenosis. Although there have been many reports and reviews on the clinical aspects of canine IVD disease, few reports have discussed and reviewed the process of IVD degeneration. In this first part of a two-part review, the anatomy, physiology, histopathology, and biochemical and biomechanical characteristics of the healthy and degenerated IVD are described. In Part 2, the aspects of IVD degeneration in chondrodystrophic and non-chondrodystrophic dog breeds are discussed in depth. 相似文献
107.
108.
ABSTRACT Separate volume regression equations for pulpwood, sawtimber and over-mature Eucalyptus grandis are presented. An investigation of Schumacher and Hall's volume equation indicated that a better fit may be obtained by adding a constant to the dbh as predictor variable. The resultant equation is: log V = ?4,2328 + 1,7154 log (D-2) + 1,1070 log H. 相似文献
109.
Anna Turska-Szewczuk Buko Lindner Iwona Komaniecka Alicja Kozinska Agnieszka Pekala Adam Choma Otto Holst 《Marine drugs》2013,11(4):1235-1255
Chemical analyses and mass spectrometry were used to study the structure of the lipopolysaccharide (LPS) isolated from Aeromonas bestiarum strain K296, serotype O18. ESI-MS revealed that the most abundant A. bestiarum LPS glycoforms have a hexa-acylated or tetra-acylated lipid A with conserved architecture of the backbone, consisting of a 1,4′-bisphosphorylated β-(1→6)-linked d-GlcN disaccharide with an AraN residue as a non-stoichiometric substituent and a core oligosaccharide composed of Kdo1Hep6Hex1HexN1P1. 1D and 2D NMR spectroscopy revealed that the O-specific polysaccharide (OPS) of A. bestiarum K296 consists of a branched tetrasaccharide repeating unit containing two 6-deoxy-l-talose (6dTalp), one Manp and one GalpNAc residues; thus, it is similar to that of the OPS of A. hydrophila AH-3 (serotype O34) in both the sugar composition and the glycosylation pattern. Moreover, 3-substituted 6dTalp was 2-O-acetylated and additional O-acetyl groups were identified at O-2 and O-4 (or O-3) positions of the terminal 6dTalp. Western blots with polyclonal rabbit sera showed that serotypes O18 and O34 share some epitopes in the LPS. The very weak reaction of the anti-O34 serum with the O-deacylated LPS of A. bestiarum K296 might have been due to the different O-acetylation pattern of the terminal 6dTalp. The latter suggestion was further confirmed by NMR. 相似文献
110.
For the selection of donors with valuable characteristics for breeding, 39 thyme accessions were evaluated in three years
according to a staggered schedule. The criteria investigated were: winter hardiness, beginning of flowering, growth height,
yield of the dry herb, content of essential oil, composition of the essential oil, DNA content of cell nuclei and number of
chromosomes. The most strongly varying traits between the populations were the yield of dry herb, the content of essential
oil and the content of volatile phenols with coefficients of variation (CV) between CV 40% and 50%. The largest variation
within a population was detected for the yield of dry herb (CV 25–46%) and the content of essential oil (CV 17–48%). The homogeneity
of the populations was different. The minimal average coefficient of variation of all traits (CV 19%) was determined in the
population of the cultivar ‘Varico II’ and in a population from Lithuania. The ploidy level of T. vulgaris was diploid (2n = 30). 相似文献