299 research outputs found
On the discourse of construction competitiveness
It is contended that competitiveness is better understood as a discourse rather than as a characteristic that is supposedly possessed. The discourse of competitiveness derives its legitimacy from the enterprise culture that came to dominance during the 1980s. Current popularized theories of competitiveness are constituent parts of this broader discourse, which has had significant material implications for the UK construction sector. The dominant discourse of competitiveness amongst contracting firms is shaped by the need to achieve structural flexibility to cope with fluctuations in demand. Fashionable espoused improvement recipes such as total quality management, business process re-engineering, and lean construction legitimize and reinforce the material manifestations of the enterprise culture. In consequence, the UK industry is characterized by a plethora of hollowed-out firms that have failed to invest in their human capital. While the adopted model may be rational for individual firms, the systemic effect across the sector as a whole equates to a form of anorexia. However, the discourse of competitiveness is by no means monolithic and continues to be contested locally. There have also been numerous counter-discourses that have been mobilized in response to the undesirable externalities of unbridled enterprise. Currently, important counter-discourses promote the ideas of sustainability and corporate social responsibility
The coronavirus endoribonuclease Nsp15 interacts with retinoblastoma tumor suppressor protein
Coronaviruses encode an endoribonuclease, Nsp15, which has a poorly defined role in infection. Sequence analysis revealed a retinoblastoma protein-binding motif (LXCXE/D) in the majority of the Nsp15 of the severe acute respiratory syndrome coronavirus (SARS-CoV) and its orthologs in the alpha and beta coronaviruses. The endoribonuclease activity of the SARS-CoV Nsp15 (sNsp15) was stimulated by retinoblastoma protein (pRb) in vitro, and the two proteins can be coimmunoprecipitated from cellular extracts. Mutations in the pRb-binding motif rendered sNsp15 to be differentially modified by ubiquitin in cells, and cytotoxicity was observed upon its expression. Expression of the sNsp15 in cells resulted in an increased abundance of pRb in the cytoplasm, decreased overall levels of pRb, an increased proportion of cells in the S phase of the cell cycle, and an enhanced expression from a promoter normally repressed by pRb. The endoribonuclease activity of the mouse hepatitis virus (MHV) A59 Nsp15 was also increased by pRb in vitro, and an MHV with mutations in the LXCXE/D-motif, named vLC, exhibited a smaller plaque diameter and reduced the virus titer by ~1 log. Overexpression of pRb delayed the viral protein production by wild-type MHV but not by vLC. This study reveals that pRb and its interaction with Nsp15 can affect coronavirus infection and adds coronaviruses to a small but growing family of RNA viruses that encode a protein to interact with pRb
Detection of Novel Enterovirus with Emergency Department Based Syndromic Surveillance System in Taipei City
Understanding procurement methods in practice: an alternative perspective
The aim of this paper is to propose an agency-structure perspective on understanding how procurement methods are enacted in practice. It is argued that procurement methods manifest within a complex web of interconnections between various actors and the industrial structure. As an example, this paper focuses on the interrelations between the quangos' promotions of procurement initiatives and construction firms' responses to these initiatives. An understanding of such interrelations is achieved by integrating three sources of data regarding procurement developments. First, an analysis of the industry is considered as structural forces which influence procurement developments. This knowledge will be obtained through a literature review of the industry, including the overall economic conditions, the state of the industry itself, and the nature of construction demands. Second, the business path development of construction firms is regarded as responses to procurement initiatives. The method of case study will be applied to understand how construction firms' business path is related to procurement initiatives of time. Finally, a review of quango construction reports will be undertaken. Each report's key recommendations and impacts related to procurement initiatives will be identified. The three sources of data will then be plotted onto a timeline graph in order to form a more in-depth analysis. An assessment of the three sources of data at a chosen point/s for interconnections and causal relationships would then be undertaken. It is concluded that considering the interrelations between the three sources of data will offer a greater understanding of procurement methods in practice
Microstructure and Optical Properties of Tantalum Modified TiO2 Thin Films Prepared by the Sol-Gel Process
Tantalum doped TiO2 thin films ((TiO2)(1-x) (Ta2O5)(x), x = 0, 0.1%, 0.3%, 0.5%, 0.8%) were prepared on ITO-coated substrates by means of the sol gel method and spin coating technology followed by rapid thermal annealing treatment (RTA). The effects of various processing parameters, including Ta content (x = 0-0.8%) and annealing temperature, on the growth and properties of thin films were investigated. Structural characteristics by X-ray diffraction analysis indicated that the doping of Ta2O5 in the TiO2 without change the anatase structure of TiO2 thin films. The optical transmittance of (TiO2)(1-x) (Ta2O5) thin films decrease from 50% down to 20% with increasing the Ta2O5 concentrations from x = 0.00 to x = 0.8%. The absorption coefficient shows energy gap were decreased with increasing Ta2O5 content from 2.932 eV for x = 0.00 to 2.717 eV for x = 0.8%. Doping TiO2 with Ta2O5 can lower its band gap and shift its optical response to the visible region
H-Ras oncogene counteracts the growth-inhibitory effect of genistein in T24 bladder carcinoma cells
Among eight human bladder cancer cell lines we examined, only T24 cells were resistant to the growth inhibition effect of genistein, an isoflavone and potent anticancer drug. Since the T24 cell line was the only cell line known to overexpress oncogenic H-Ras(val12), we investigated the role of H-Ras(val 12) in mediating drug resistance. Herein, we demonstrate that the phenotype of T24 cells could be dramatically reversed and became relatively susceptible to growth inhibition by genistein if the synthesis of H- Ras(val 12) or its downstream effector c-Fos had been suppressed. The inhibition of Ras-mediated signalling with protein kinase inhibitors, such as PD58059 and U0126 which inhibited MEK and ERK, in T24 cells also rendered the identical phenotypic reversion. However, this reversion was not observed when an inhibitor was used to suppress the protein phosphorylation function of PI3 K or PKC. These results suggest that the signal mediated by H-Ras(val 12) is predominantly responsible for the resistance of the cells to the anticancer drug genistein
Photoluminescence Properties of the Zn1-x Y (x) O Tubes Prepared by Polycarbonate Templates
We have prepared Zn1-x Y (x) O (x=0 and 0.01) tubes to study its structural and photoluminescent properties. A pore wetting process of porous polycarbonate templates with the liquid precursor and following thermal treatment were utilized for preparing the Zn1-x Y (x) O tube structure. Using the polycarbonate template with pore size of about 2 mu m diameter, the Zn1-x Y (x) O tubes were obtained. Photoluminescence (PL) spectroscopy was used to measure optical emissions from 350 to 650 nm with a He-Cd laser. The results of the PL spectra show that the Zn1-x Y (x) O tubes have evident emission peaks at the UV (about 380 nm) and visible (around 500 to 650 nm) region. The emission peak at the UV region was slightly shifted to higher wavelengths with increasing Y content. Meanwhile, the green and yellow emission peaks intensity increases as Y content increases. These results are explained by the structure tuning and oxygen deficiency with the introduction of Y
Interface ferromagnetism and orbital reconstruction in BiFeO3- La0.7Sr0.3MnO3 heterostructures
We report the formation of a novel ferromagnetic state in the antiferromagnet
BiFeO3 at the interface with La0.7Sr0.3MnO3. Using x-ray magnetic circular
dichroism at Mn and Fe L2,3-edges, we discovered that the development of this
ferromagnetic spin structure is strongly associated with the onset of a
significant exchange bias. Our results demonstrate that the magnetic state is
directly related with an electronic orbital reconstruction at the interface,
which is supported by the linearly polarized x-ray absorption measurement at
oxygen K-edge.Comment: 17 pages, 4 figures, PRL in pres
Anomalous c-axis charge dynamics in copper oxide materials
Within the t-J model, the c-axis charge dynamics of the copper oxide
materials in the underdoped and optimally doped regimes is studied by
considering the incoherent interlayer hopping. It is shown that the c-axis
charge dynamics is mainly governed by the scattering from the in-plane
fluctuation. In the optimally doped regime, the c-axis resistivity is a linear
in temperatures, and shows the metallic-like behavior for all temperatures,
while the c-axis resistivity in the underdoped regime is characterized by a
crossover from the high temperature metallic-like behavior to the low
temperature semiconducting-like behavior, which are consistent with experiments
and numerical simulations.Comment: 6 pages, Latex, Three figures are adde
Direct characterization of photo-induced lattice dynamics in BaFeâAsâ
Ultrafast light pulses can modify electronic properties of quantum materials by perturbing the underlying, intertwined degrees of freedom. In particular, iron-based superconductors exhibit a strong coupling among electronic nematic fluctuations, spins and the lattice, serving as a playground for ultrafast manipulation. Here we use time-resolved X-ray scattering to measure the lattice dynamics of photoexcited BaFeAs. On optical excitation, no signature of an ultrafast change of the crystal symmetry is observed, but the lattice oscillates rapidly in time due to the coherent excitation of an A mode that modulates the FeâAsâFe bond angle. We directly quantify the coherent lattice dynamics and show that even a small photoinduced lattice distortion can induce notable changes in the electronic and magnetic properties. Our analysis implies that transient structural modification can be an effective tool for manipulating the electronic properties of multi-orbital systems, where electronic instabilities are sensitive to the orbital character of bands
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