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51.
Jeffrey H. Dinitz Maura B. Paterson Douglas R. Stinson Ruizhong Wei 《Designs, Codes and Cryptography》2012,65(3):325-351
Li et al. (Retransmission ≠ repeat: simple retransmission permutation can resolve overlapping channel collisions, 2009) introduced a technique for resolving overlapping channel transmissions that used an interesting new type of combinatorial structure. In connection with this problem, they provided an example of a 4 × 4 array having certain desirable properties. We define a class of combinatorial structures, which we term retrans mission permutation arrays, that generalise the example that Li et?al. provided. We show that these arrays exist for all possible orders. We also define some extensions having additional properties, for which we provide some partial results. 相似文献
52.
Silvia Burlina Cristina Banfi Maura Brioschi Silvia Visentin Maria Grazia Dalfr Pietro Traldi Annunziata Lapolla 《Journal of mass spectrometry : JMS》2019,54(4):359-365
In pregnancy complicated by gestational diabetes mellitus (GDM), the human placenta shows several pathological functional and structural changes, but the extent to which maternal glycemic control contributes to placental abnormalities remains unclear. The aim of this study was to profile and compare the proteome of placentas from healthy pregnant women and those with GDM, to investigate the placenta‐specific protein composition and possible changes of its function in presence of GDM. Quantitative proteomic analysis, based on LC‐MSE approach, revealed that higher (approximately 15% increase) levels of galectin 1 and collagen alpha‐1 XIV chain (although the difference regarding the latter was at the limit of significance) were present in GDM samples, while heat shock 70 kDa protein 1A/1B was less abundant in GDM placental tissue. These data seem to indicate that GDM, when well controlled, did not markedly affect the placental proteome. 相似文献
53.
We consider the wind-forced nonlinear Schrödinger (NLS) equation obtained in the potential flow framework when the Miles growth rate is of the order of the wave steepness. In this case, the form of the wind-forcing terms gives rise to the enhancement of the modulational instability and to a band of positive gain with infinite width. This regime is characterised by the fact that the ratio between wave momentum and norm is not a constant of motion, in contrast to what happens in the standard case where the Miles growth rate is of the order of the steepness squared. 相似文献
54.
Maria Gregori Daniela Bertani Emanuela Cazzaniga Antonina Orlando Michele Mauri Alberto Bianchi Francesca Re Silvia Sesana Stefania Minniti Maura Francolini Alfredo Cagnotto Mario Salmona Luca Nardo Domenico Salerno Francesco Mantegazza Massimo Masserini Roberto Simonutti 《Macromolecular bioscience》2015,15(12):1687-1697
55.
Skin secretion peptides: the molecular facet of the deimatic behavior of the four‐eyed frog,Physalaemus nattereri (Anura,Leptodactylidae) 下载免费PDF全文
56.
57.
27 AI and 31P spectroscopy is employed to give direct insight into the adsorption phenomena at a TiO2 surface of aluminium and pyrophosphate ions used as flocculating and dispersing agents, respectively. A direct adsorption of these species on the TiO2 pigment is suggested, and a cooperative interaction between the ions and colloidal particles together with a desorption of bound species with increasing pH are observed. 相似文献
58.
Maura Salvatori 《Journal of Theoretical Probability》1992,5(3):563-576
In this paper we consider reversible random walks on an infinite grapin, invariant under the action of a closed subgroup of automorphisms which acts with a finite number of orbits on the vertex-set. Thel
2-norm (spectral radius) of the simple random walk is equal to one if and only if the group is both amenable and unimodular, and this also holds for arbitrary random walks with bounded invariant measure. In general, the norm is bounded above by the Perron-Frobenius eigenvalue of a finite matrix, and this bound is attained if and only if the group is both amenable and unimodular. 相似文献
59.
The new dihydridobis(3-nitro-1,2,4-triazolyl)borate ligand, [H2B(tzNO2)2]-, has been synthesized in dimethylacetamide solution, using 3-nitro-1,2,4-triazole and KBH4 through careful temperature control, and characterized as its potassium salt. The zinc(II) and cadmium(II) complexes, {M[H2B(tzNO2)2]Cl(H2O)2}, have been prepared by metathesis of [H2B(tzNO2)2]K with ZnCl2 and CdCl2, respectively. The complexes likely contain a metal core in which the ligand is coordinated to the metal ions in the K2-N,N' or K4-N,N',O,O' fashion. A single-crystal structural characterization is reported for the potassium dihydrobis(3-nitro-1,2,4-triazolyl)borate. The potassium salt is polymeric and shows several K...N and K...O interactions. 相似文献
60.
Gioia Lobbia G Hanna JV Pellei M Pettinari C Santini C Skelton BW White AH 《Dalton transactions (Cambridge, England : 2003)》2004,(6):951-958
Gold derivatives [Au(Tpx)(PR3)](Tpx = Tp, hydrotris(pyrazol-1-yl)borate or Tp*, hydrotris(3,5-dimethylpyrazol-1-yl)borate; R = Ph or tBu) and [Au(pzTp)(PR3)x](pzTp = tetrakis(pyrazol-1-yl)borate, x = 1 or 2, R = Ph or tBu) have been synthesised and characterized both in solution (1H- and 31P[1H]-NMR) and in the solid state (IR, single crystal X-ray structure analysis, 31P CPMAS). 31P [1H] NMR solution data suggest greater stability of the tetrakis(pyrazolyl)borate relative to those of tris(pyrazolyl)borate. All compounds are fluxional at room temperature. In order to compare [Au(Tp*)(PPh3)] with analogous coinage metal adducts we have synthesized and structurally characterized [Cu(Tp*)(PPh3)] x PPh3 and [Ag(Tp*)(PPh3)] x 2MeCN. In [Au(Tp*)(PPh3)] the gold atom adopts a distorted tetrahedral geometry with 2.181(5) and 2.37(2) angstroms (cf. 2.166(6), 2.098(1) in [Cu(Tp*)PPh3], 2.156(2), 2.075(7) in [Cu(Tp*)(PPh3)] x PPh3; and in [Ag(Tp*)PPh3] x MeCN 2.347(12), 2.35(5) angstroms). There are three independent [Au(Tp*)(PPh3)] molecules in the asymmetric unit of the structure with their PAu...B axes lying on the cell diagonal of a cubic P213 cell, two with the same chirality aligned opposed in direction to the third which is of opposite chirality. A number of Cu, Ag and Au complexes containing scorpionate ligands have also been investigated by 31P cross-polarization magic-angle-spinning (CPMAS) NMR spectroscopy. 相似文献