73 resultados para Internal Transcribed Spacer Unit 2


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Foundation construction process has been an important key point in a successful construction engineering. The frequency of using diaphragm wall construction method among many deep excavation construction methods in Taiwan is the highest in the world. The traditional view of managing diaphragm wall unit in the sequencing of construction activities is to establish each phase of the sequencing of construction activities by heuristics. However, it conflicts final phase of engineering construction with unit construction and effects planning construction time. In order to avoid this kind of situation, we use management of science in the study of diaphragm wall unit construction to formulate multi-objective combinational optimization problem. Because the characteristic (belong to NP-Complete problem) of problem mathematic model is multi-objective and combining explosive, it is advised that using the 2-type Self-Learning Neural Network (SLNN) to solve the N=12, 24, 36 of diaphragm wall unit in the sequencing of construction activities program problem. In order to compare the liability of the results, this study will use random researching method in comparison with the SLNN. It is found that the testing result of SLNN is superior to random researching method in whether solution-quality or Solving-efficiency.

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A four-wavelength MAD experiment on a new brominated octanucleotide is reported here. d[ACGTACG(5-BrU)], C77H81BrN30O32P7, (DNA) = 2235, tetragonal, P43212 (No. 96), a = 43.597, c = 26.268 Å, V = 49927.5 Å3, Z = 8, T = 100 K, R = 10.91% for 4312 reflections between 15.0 and 1.46 Å resolution. The self-complementary brominated octanucleotide d[ACGTACG(5-BrU)]2 has been crystallized and data measured to 1.45 Å at both 293 K and a second crystal flash frozen at 100 K. The latter data collection was carried out to the same resolution at the four wavelengths 0.9344, 0.9216, 0.9208 and 0.9003 Å, around the Br K edge at 0.92 Å and the structure determined from a map derived from a MAD data analysis using pseudo-MIR methodology, as implemented in the program MLPHARE. This is one of the first successful MAD phasing experiments carried out at Sincrotrone Elettra in Trieste, Italy. The structure was refined using the data measured at 0.9003 Å, anisotropic temperature factors and the restrained least-squares refinement implemented in the program SHELX96, and the helical parameters are compared with those previously determined for the isomorphous d(ACGTACGT)2 analogue. The asymmetric unit consists of a single strand of octamer with 96 water molecules. No countercations were located. The A-DNA helix geometry obtained has been analysed using the CURVES program.

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d(ACGTACGT), C78H84N30O32P7.20H2O, Mr (DNA) = 2170, tetragonal, P43212 (No 96), a = 42.845 (1), b = 42.845(1), c = 24.804 (1) Å, V = 45532.5 (2) Å3, z = 8,(MoK) = 0.71069 Å,µ(MoK) = 0.10 mm-1, T = 295 K, R = 0.18 for 1994 unique reflections between 5.0 and 1.9 Å resolution. The self-complementary octanucleotide d(ACGTACGT)2 has been crystallized and its structure determined to a resolution of 1.9 Å. The asymmetric unit consists of a single strand of octamer with 20 water molecules. It is only the second example of an octanucleotide having terminal A·T base pairs whose structure has been determined by X-ray crystallography. The sequence adopts the modified A-type conformation found for all octanucleotide duplexes studied to date with the helix bent by approximately 15° and an average tilt angle of 0°. Unusually the data collection was carried out using a 3 kW molybdenum sealed-tube source. The conformational details are discussed in comparison with other closely related sequences.

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Benzene-1,2-dioxyacetic acid (bdoaH2) reacts with Mn(CH3CO2)2·4H2O in an ethanol-water mixture to give the manganese(II) complex [Mn(bdoa)(H2O)3]. The X-ray crystal structure of the complex shows the metal to be pseudo seven-coordinate. The quadridentate bdoa2− dicar☐ylate ligand forms an essentially planar girdle around the metal, being strongly bondedtransoid by a car☐ylate oxygen atom from each of the two car☐ylate moieties (mean MnO 2.199A˚) and also weakly chelated by the two internal ether oxygen atoms (mean MnO 2.413A˚). The coordination sphere about the manganese is completed by three water molecules (mean MnO 2.146A˚) lying in a meridional plane orthogonal to that of the bdoa2− ligand. Magnetic, conductivity and voltammetry data for the complex are given, and its use as a catalyst for the disproportionisation of H2O2 is described.

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The species [{Sn(C2H2iPr3-2,4,6)2}3] has been obtained in a simple, essentially quantitative, synthesis from SnCl2 and ArLi in diethyl ether at low temperature. The crystal structure analysis confirms the trimeric nature of the molecular units but reveals some unusual features. The crystal contains the unusual feature of an asymmetric unit that consists of three units of [{SnAr2}3] in P21/c; the molecular unit is a scalene triangle, showing high consistency between the three molecules, in contrast to analogous trimeric species of silicon or germanium. The SnSn bonds are lengthened (average value 2.942 Å) owing to steric crowding.

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Studies of the 1H n.m.r. and electronic spectra of a series of alkenylferrocenes including (E) and (Z) stereoisomers of various styrylferrocenes, have provided methods of structure elucidation. Crystals of the title compound are monoclinic, space group P21/c with Z= 4 in a unit cell of dimensions a= 17.603(2), b= 10.218(2), c= 10.072 Å, β= 103.27(2)°. The structure has been determined by the heavy-atom method from diffractometer data and refind by full-matrix least-squares techniques to R= 0.043 for 2 219 unique reflections.

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Two novel, monomeric heteroleptic tin(II) derivatives, [Sn{2-[(Me3Si)2C]C5H4N}R] [R = C6H2Pri3-2,4,6 1 or CH(PPh2)2 2], have been prepared, characterised by multinuclear NMR spectroscopies and their molecular structures determined by single crystal X-ray diffraction. Both compounds were prepared from the corresponding heteroleptic tin(II) chloro-analogue, [Sn{2-[(Me3Si)2C]C5H4N}Cl], and thus demonstrate the utility of this compound as a precursor to further examples of heteroleptic tin(II) derivatives: such compounds are often unstable with respect to ligand redistribution. In each case, the central tin(II) is three-co-ordinate. Crystals of trimeric [{Sn(C6H2Pri3-2,4,6)2}3] 3 were found to undergo a solid state phase transition, which may be ascribed to ordering of the ligand isopropyl groups. At 220 K the unit cell is orthorhombic, space group Pna21, compared with monoclinic, space group P21/c, for the same crystals at 298 K, in which there is an effective tripling of the now b (originally c) axis. This result illustrates the extreme crowding generated by this bulky aryl ligand.

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We introduce the notion that the energy of individuals can manifest as a higher-level, collective construct. To this end, we conducted four independent studies to investigate the viability and importance of the collective energy construct as assessed by a new survey instrument—the productive energy measure (PEM). Study 1 (n = 2208) included exploratory and confirmatory factor analyses to explore the underlying factor structure of PEM. Study 2 (n = 660) cross-validated the same factor structure in an independent sample. In study 3, we administered the PEM to more than 5000 employees from 145 departments located in five countries. Results from measurement invariance, statistical aggregation, convergent, and discriminant-validity assessments offered additional support for the construct validity of PEM. In terms of predictive and incremental validity, the PEM was positively associated with three collective attitudes—units' commitment to goals, the organization, and overall satisfaction. In study 4, we explored the relationship between the productive energy of firms and their overall performance. Using data from 92 firms (n = 5939employees), we found a positive relationship between the PEM (aggregated to the firm level) and the performance of those firms. Copyright © 2011 John Wiley & Sons, Ltd.

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Research in the late 1980s showed that in many corporate real estates users were not fully aware of the full extent of their property holdings. In many cases, not only was the value of the holdings unknown, but there was uncertainty over the actual extent of ownership within the portfolio. This resulted in a large number of corporate occupiers reviewing their property holdings during the 1990s, initially to create a definitive asset register, but also to benefit from an more efficient use of space. Good management of corporately owned property assets is of equal importance as the management of other principal resources within the company. A comprehensive asset register can be seen as the first step towards a rational property audit. For the effective, efficient and economic delivery of services, it is vital that all property holdings are utilised to the best advantage. This requires that the property provider and the property user are both fully conversant with the value of the property holding and that an asset/internal rent/charge is made accordingly. The advantages of internal rent charging are twofold. Firstly, it requires the occupying department to “contribute” an amount to the business equivalent to the open market rental value of the space that it occupies. This prevents the treating of space as a free good and, as individual profit centres, each department will then rationalise its holdings to minimise its costs. The second advantage is from a strategic viewpoint. By charging an asset rent, the holding department can identify the performance of its real estate holdings. This can then be compared to an internal or external benchmark to help determine whether the company has adopted the most efficient tenure pattern for its properties. This paper investigates the use of internal rents by UK-based corporate businesses and explains internal rents as a form of transfer pricing in the context of management and responsibility accounting. The research finds that the majority of charging organisations introduced internal rents primarily to help calculate true profits at the business unit level. However, less than 10% of the charging organisations introduced internal rents primarily to capture the return on assets within the business. There was also a sizeable element of the market who had no plans to introduce internal rents. Here, it appears that, despite academic and professional views that internal rents are beneficial in improving the efficient use of property, opinion at the business and operational level has not universally accepted this proposition.

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This article examines the superficial and deep ethical and moral dilemmas confronting ‘insider’ researchers which we term external and internal ethical engagement. External ethical engagement refers to the traditional, easily identifiable ethical issues that insider researchers attend to by submitting their application for ethical approval to their institution’s internal review board. Internal ethical engagement relates to the deeper level ethical and moral dilemmas that insider researchers have to deal with once ‘in the field’ linked to on-going personal and professional relationships with participants, insider knowledge, conflicting professional and researcher roles, and anonymity. By reviewing the literature in this area and drawing on the authors’ experiences of undertaking interpretive studies at institutions where they were members of staff, we explore these concepts and examine the implications for insider researchers. Keywords: insider research; ethics; professional relationships; anonymity; access

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G.A. Cohen's Rescuing Justice and Equality is the culmination of twenty years' work on Rawls's theory of justice. In this paper I distinguish three prongs of attack advanced by Cohen, and show how two of the prongs (the claim that egalitarianism includes productive demands and the claim that equality is best understood as 'luck egalitarianism') are incompatible.

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The crystallization behaviour of a series of random copolymers of varying chemical composition is reported. For polymers containing a high proportion of alternating rigid aromatic units and flexible spacers, conventional liquid crystalline and crystalline phase behaviour is observed. The introduction of a substantial fraction of a second shorter rigid unit containing side-chains leads to a broad endotherm in the d.s.c. scan covering some 150°C. Subsequent isothermal crystallization at any point within the broad endotherm leads to the generation of sharp endotherms at temperatures just above the recrystallization temperature. We attribute this behaviour to the crystallization of clusters of molecules containing similar random sequences. Such crystals are non-periodic along the chain direction.

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In language contact studies, specific features of the contact languages are often seen to be the result of transfer (interference), but it remains difficult to disentangle the role of intra-systemic and inter-systemic factors. We propose to unravel these factors in the analysis of a feature of Brussels French which many researchers attribute to transfer from (Brussels) Dutch: the adverbial use of une fois. We compare the use of this particle in Brussels French with its occurrence in corpora of other varieties of French, including several that have not been influenced by a Germanic substrate or adstrate. A detailed analysis of the frequency of occurrence, the functions and the distribution of the particle over different syntactic positions shows that some uses of une fois can be traced back to sixteenth-century French, but that there is also ample evidence for overt and covert transfer (Mougeon and Beniak, 1991) from Brussels Dutch.

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Our understanding of vascular endothelial cell physiology is based on studies of endothelial cells cultured from various vascular beds of different species for varying periods of time. Systematic analysis of the properties of endothelial cells from different parts of the vasculature is lacking. Here, we compare Ca(2+) homeostasis in primary cultures of endothelial cells from human internal mammary artery and saphenous vein and how this is modified by hypoxia, an inevitable consequence of bypass grafting (2.5% O(2), 24 h). Basal [Ca(2+)]( i ) and store depletion-mediated Ca(2+) entry were significantly different between the two cell types, yet agonist (ATP)-mediated mobilization from endoplasmic reticulum stores was similar. Hypoxia potentiated agonist-evoked responses in arterial, but not venous, cells but augmented store depletion-mediated Ca(2+) entry only in venous cells. Clearly, Ca(2+) signaling and its remodeling by hypoxia are strikingly different in arterial vs. venous endothelial cells. Our data have important implications for the interpretation of data obtained from endothelial cells of varying sources.

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Three new Mn(II) coordination compounds {[Mn(NCNCN)2(azpy)]·0.5azpy}n (1), {[Mn(NCS)2(azpy)(CH3OH)2]·azpy}n (2), and [Mn(azpy)2(H2O)4][Mn(azpy)(H2O)5]·4PF6·H2O·5.5azpy (3) (where azpy = 4,4'-azobis-(pyridine)) have been synthesized by self-assembly of the primary ligands, dicyanamide, thiocyanate, and hexafluorophosphate, respectively, together with azpy as the secondary spacer. All three complexes were characterized by elemental analyses, IR spectroscopy, thermal analyses, and single crystal X-ray crystallography. The structural analyses reveal that complex 1 forms a two-dimensional (2D) grid sheet motif These sheets assemble to form a microporous framework that incorporates coordination-free azpy by host-guest pi center dot center dot center dot pi. and C-H center dot center dot center dot N hydrogen bonding interactions. Complex 2 features azpy bridged one-dimensional (ID) chains of centrosymmetric [Mn(NCS)(2)(CH3OH)(2)} units which form a 2D porous sheet via a CH3 center dot center dot center dot pi supramolecular interaction. A guest azpy molecule is incorporated within the pores by strong H-bonding interactions. Complex 3 affords a 0-D motif with two monomeric Mn(II) units in the asymmetric unit. There exist pi center dot center dot center dot pi, anion center dot center dot center dot pi, and strong hydrogen bonding interactions between the azpy, water, and the anions. Density functional theory (DFT) calculations, at the M06/6-31+G* level of theory, are used to characterize a great variety of interactions that explicitly show the importance of host-guest supramolecular interactions for the stabilization of coordination compounds and creation of the fascinating three-dimensional (3D) architecture of the title compounds.