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61.
The extracellular matrix protein Pl-nectin, a 210-kDa homodimer originally purified from sea urchin eggs, plays a crucial role in cell adhesion and embryonic morphogenesis. The compiled cDNA sequence, obtained by RT-PCR primer walking and 3′ RACE, identified a 984aa product containing a 23aa signal peptide and including all six internal peptides identified by protein microsequencing. The protein is a new member of the galactose-binding protein superfamily as it consists of six 151–156aa-long tandemly repeated domains (D1–D6), homologous to the discoidin-like domains, also known as F5/8-type C domains. Based on homology modelling, we present a three-dimensional structure (3D) for D5, identified as the prototype domain. The molecular modelling of the assembled Pl-nectin homodimer accounts for a Pl-nectin quaternary structure composed of two 105-kDa C-shaped monomers linked by a S–S bridge. The presence of an LDT motif between the first and the second exposed loops of the D2 domain suggests the binding of Pl-nectin to an integrin receptor. Altogether, the in silico analysis described here is consistent with previous biochemical reports and offers a basis for predictions to be experimentally tested.  相似文献   
62.
We perform a likelihood analysis of the minimal anomaly-mediated supersymmetry-breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that either a wino-like or a Higgsino-like neutralino LSP, \(\tilde{\chi }^0_{1}\), may provide the cold dark matter (DM), both with similar likelihoods. The upper limit on the DM density from Planck and other experiments enforces \(m_{\tilde{\chi }^0_{1}} \lesssim 3 \,\, \mathrm {TeV}\) after the inclusion of Sommerfeld enhancement in its annihilations. If most of the cold DM density is provided by the \(\tilde{\chi }^0_{1}\), the measured value of the Higgs mass favours a limited range of \(\tan \beta \sim 5\) (and also for \(\tan \beta \sim 45\) if \(\mu > 0\)) but the scalar mass \(m_0\) is poorly constrained. In the wino-LSP case, \(m_{3/2}\) is constrained to about \(900\,\, \mathrm {TeV}\) and \(m_{\tilde{\chi }^0_{1}}\) to \(2.9\pm 0.1\,\, \mathrm {TeV}\), whereas in the Higgsino-LSP case \(m_{3/2}\) has just a lower limit \(\gtrsim 650\,\, \mathrm {TeV}\) (\(\gtrsim 480\,\, \mathrm {TeV}\)) and \(m_{\tilde{\chi }^0_{1}}\) is constrained to \(1.12 ~(1.13) \pm 0.02\,\, \mathrm {TeV}\) in the \(\mu >0\) (\(\mu <0\)) scenario. In neither case can the anomalous magnetic moment of the muon, \((g-2)_\mu \), be improved significantly relative to its Standard Model (SM) value, nor do flavour measurements constrain the model significantly, and there are poor prospects for discovering supersymmetric particles at the LHC, though there are some prospects for direct DM detection. On the other hand, if the \(\tilde{\chi }^0_{1}\) contributes only a fraction of the cold DM density, future LHC Open image in new window -based searches for gluinos, squarks and heavier chargino and neutralino states as well as disappearing track searches in the wino-like LSP region will be relevant, and interference effects enable \(\mathrm{BR}(B_{s, d} \rightarrow \mu ^+\mu ^-)\) to agree with the data better than in the SM in the case of wino-like DM with \(\mu > 0\).  相似文献   
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64.
In this work we investigate magnonic band gaps, in the terahertz (THz) frequency range, in periodic and quasiperiodic (Fibonacci sequence) magnonic crystals formed by layers of Cobalt (Co) and Permalloy (Py). Our theoretical model is based on a magnetic Heisenberg Hamiltonian in the exchange regime, together with a transfer-matrix treatment within the random-phase approximation (RPA). For periodic arrangements the bulk band structure is analogous to those found in photonic crystals, while for quasiperiodic multilayers it presents additional pass bands similar to those found in doped electronic materials.  相似文献   
65.
The Cr 2p and O 1s binding energy (BE) levels have been calculated by first principles methods for different models of hydroxylated (0001)-Cr2O3 surfaces. Several surface terminations have been considered. The calculations allow us to reproduce the O 1s shifts between O in oxide and OH groups. It is found that two main effects account for the OH binding energy shifts. On the one hand, the increased covalency of the O–H bond with respect to the Cr–O bond, lowers the electronic O (1s and 2p) energy, and in consequence the BE of the core levels (O 1s) are higher. On the other hand, the lower the OH coordination number, the higher the valence and core levels energy, and the lower the BE. Consequently, mono-coordinated hydroxyls have a binding energy near that of O2? in the oxide (ΔBEOH–O = ? 0.2–0.0 eV). Two-fold coordinated hydroxyls have a slightly higher BE (ΔBEOH–O = + 0.3 eV). Three-fold coordinated OH groups have a higher binding energy (ΔBEOH–O = + 0.6?0.7 eV), corresponding to that experimentally measured for OH groups. Finally, water adsorbed above OH groups exhibits a still higher BE (ΔBEHOH–O = + 0.9–1.0 eV). The ΔBE are slightly under-estimated under the initial state approximation, and overestimated under the final state (Z + 1) approximation.  相似文献   
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67.
Blood oxygenation level dependent (BOLD) response related to interictal activity was evaluated in a patient with post-traumatic focal epilepsy at repeated continuous electroencephalogram (EEG)-functional magnetic resonance imaging examinations. Lateralized interictal EEG activity induced a main cluster of activation co-localized with the anatomical lesion. Spreading of EEG interictal activity to both frontal lobes evoked bilateral clusters of activation indicating that topography of BOLD response might depend on the spatial distribution of epileptiform activity.  相似文献   
68.
Laser Physics - The aim of the present study was to compare marginal infiltration in Class V cavities prepared on extracted human premolars with either high-speed rotation or a Er:YAG laser. Class...  相似文献   
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70.
The reaction of tin(IV) tetrachloride with 3-formylpyridine semicarbazone and different 3-formylpyridine thiosemicarbazones produces [Sn(HL)CL 3 ][SnCl 5 ] where HL stands for the neutral ligand. The tin(IV) complexes were characterized using a variety of spectroscopic techniques. Coordination through the pyridine nitrogen occurs in all cases. Solvation studies in DMSO indicated that dissociation of the ligands and their complete replacement by solvent molecules occurs.  相似文献   
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