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UK Skills and Productivity in an International Context
A nation's prosperity depends largely on its ability to raise the level of its productivity. The education level of its workforce, and how effectively the skills are used in the production processes, are considered important factors in this process. In this report we investigate the extent to which skills have contributed to recent productivity performance in the UK. We do this within a cross-country framework, where we compare the UK's productivity trajectories with those of other close competitors. We quantify the role played by different types of certified skills, both academic and vocational, taking account of the influence of other factors, such as capital investment and technological change. Furthermore, we assess the influence of intangible investments, usually excluded from published data and traditional growth studies. We use a wide range of data sources, and employ growth accounting and panel data econometric techniques.
The study begins with a comprehensive review of the literature on the role of human capital in productivity and growth, from both a theoretical and empirical point of view (section 1). We then provide a description of aggregate productivity and employment trends in section 2. Section 3 contains detailed results of the growth accounting decomposition and Section 4 summarises the econometric analysis. Sections 5 and 6 outline the key findings and conclusions emerging from this analysis.
The main research questions addressed in this report are:
• What have been the main sources of growth in the UK and other major economies since the recession? How have these differed relative to the previous periods?
• What is the link between skills and productivity/growth? How have skills contributed to growth over recent years?
• What is the contribution of different types of skills to growth? Where does the UK fare better and worse compared to international competitors?
• What is the role of training and other intangible assets in explaining productivity and growth outcomes? Do they interact differently with different types of skilled workers
Effect of grain refinement on enhancing critical current density and upper critical field in undoped MgB2 ex-situ tapes
Ex-situ Powder-In-Tube MgB2 tapes prepared with ball-milled, undoped powders
showed a strong enhancement of the irreversibility field H*, the upper critical
field Hc2 and the critical current density Jc(H) together with the suppression
of the anisotropy of all of these quantities. Jc reached 104 A/cm2 at 4.2 K and
10 T, with an irreversibility field of about 14 T at 4.2 K, and Hc2 of 9 T at
25 K, high values for not-doped MgB2. The enhanced Jc and H* values are
associated with significant grain refinement produced by milling of the MgB2
powder, which enhances grain boundary pinning, although at the same time also
reducing the connectivity from about 12% to 8%. Although enhanced pinning and
diminished connectivity are in opposition, the overall influence of ball
milling on Jc is positive because the increased density of grains with a size
comparable with the mean free path produces strong electron scattering that
substantially increases Hc2, especially Hc2 perpendicular to the Mg and B
planes.Comment: 26 pages, 9 figures, submitted to J. Appl. Phy
Cage effect in supercooled molecular liquids: Local anisotropies and collective solid-like response
Both local geometry and collective extended excitations drive the moves of a particle in the cage of its neighbours in dense liquids. The strength of their influence is investigated by the molecular dynamics simulations of a supercooled liquid of fully flexible trimers with semirigid or rigid bonds. The rattling in the cage is investigated on different length scales. First, the rattling anisotropy due to local order is characterized by two order parameters sensing the monomers succeeding or failing to escape from the cage. Then the collective response of the surroundings excited by the monomer-monomer collisions is considered. The collective response is initially restricted to the nearest neighbours of the colliding particle by a Voronoi analysis revealing elastic contributions. Then the long-range excitation of the farthest neighbours is scrutinised by searching spatially extended correlations between the simultaneously fast displacements of the caged particle and the surroundings. It is found that the longitudinal component has stronger spatial modulation than the transverse one with a wavelength of about one particle diameter, in close resemblance with experimental findings on colloids. It is concluded that the cage rattling is largely affected by solid-like extended modes
Hydrogen Peroxide Induces Heme Degradation and Protein Aggregation in Human Neuroglobin: Roles of the Disulfide Bridge and the H-bonding in the Distal Heme Cavity
In this study, human neuroglobin (hNgb) was found to undergo H2O2-induced breakdown of the heme center at a much slower rate than other globins, namely in the timescale of hours against minutes. We studied how the rate of the process is affected by the Cys46/Cys55 disulfide bond and the network of noncovalent interactions in the distal heme side involving Tyr44, Lys67, the His64 heme iron axial ligand and the heme propionate-7. The rate is increased by the Tyr44 to Ala and Phe mutations, however the rate is lowered by Lys67 to Ala swapping. The absence of the disulfide bridge slows down the reaction further. Therefore, the disulfide bond-controlled accessibility of the heme site and the residues at position 44 and 67 affect the activation barrier of the reaction. Wild-type and mutated species form -amyloid aggregates in the presence of H2O2 producing globular structures. Furthermore, the C46A/C55A, Y44A, Y44F and Y44F/C46A/C55A variants yield potentially harmful fibrils. Finally, the nucleation and growth kinetics for the aggregation of the amyloid structures can be successfully described by the Finke-Watzky model
Fabrication and superconducting properties of multifilamentary MgB2 conductors for AC purposes: twisted tapes and wires with very thin filaments
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Aumento da resistência mecanica a penetração em função da perda natural de umidade no solo.
Nosso objetivo foi verificar a variação de umidade e sua interferência sobre a resistência mecânica a penetração em um latossolo amarelo disrófico (Lad) sobre relevo plano em área de pastagem, sob condições de clima Amazônico, através de modelo estatÃsticos de regressão polinomial de 2º grau
Low-field Instabilities in NbSn Multifilamentary Wires: the Possible Role of Unreacted Nb
We report an experimental study aiming to demonstrate the not negligible role of unreacted Nb on the magnetic instabilities in superconducting NbSn multifilamentary wires, observable through partial flux jumps at magnetic field values below 0.5 T. The analysed wires were recently developed for use as dipoles required in future high-energy proton accelerators and are based on powder-in-tube technology. We studied both unreacted (only involving Nb filaments) and reacted wires, finding flux jump instabilities in both cases when performing magnetic measurements. The results can be interpreted on the basis of the critical state model and are coherent with the intrinsic stability criterion
Frações granulométricas e oxidáveis da matéria orgânica do solo em sucessão floresta - pastagem no Acre.
A conversão de floresta nativa em pastagem provoca mudanças no conteúdo das frações da matéria orgânica do solo (MOS). O objetivo deste trabalho foi avaliar as alterações ocorridas nas frações granulométricas e oxidáveis da MOS em Sucessão Floresta - Pastagem no Acre. Após a derrubada e queima da floresta, implantou-se a pastagem de braquiária. Nas duas áreas foram coletadas amostras de solo nas profundidades de 0-5 e 5-10 cm. Nestas, foram avaliados os conteúdos de carbono orgânico total (COT), carbono orgânico particulado (COp), carbono orgânico associado aos minerais (COam) e carbono das frações oxidáveis (F1, F2, F3 e F4). Verificou-se que, independente da profundidade, os maiores valores de COT, COp e carbono na F1 e F3 foram encontrados na área de floresta. A retirada da vegetação original para a implantação da pastagem diminuiu os teores de COT, COp e na F1, demonstrando a maior fragilidade desses ecossistemas.Edição dos Resumos do VI CBA e II CLAA
Novel Optical Chemical Sensor Based on Molecularly Imprinted Polymer Inside a Trench Micro-machined in Double Plastic Optical Fiber☆
Abstract For the detection of chemical agents in different environments, the combination of plastic optical fibers (POFs) and molecularly imprinted polymer (MIP) layers has been tested as a way to obtain a low cost, highly selective and sensitive surface plasmon resonance (SPR) chemical sensor. A novel type of optical chemical sensor based on POF-MIP has been designed and fabricated, and in this work it has been applied for the selective detection of dibenzyl disulfide (DBDS) in transformer oil. This analyte is important in the control of transformer oil, since it is responsible for the corrosive properties of the oil. The new optical sensor platform is based on two plastic optical fibers coupled through a polymer molecularly imprinted for DBDS. The new sensor has been found to be useful for the determination of DBDS in transformer oil
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