992 resultados para cash conversion cycle
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The life cycle concept has come to have considerable prominence in Irish social policy debate. However, this has occurred without any systematic effort to link its usage to the broader literature relating to the concept. Nor has there been any detailed consideration of how we should set about operationalising the concept. In this paper we argue the need for "macro" life cycle perspectives that have been influenced by recent challenges to the welfare state to be combined with "micro" perspectives focusing on the dynamic and multidimensional nature of social exclusion. We make use of Irish EU-SILC 2005 data in developing a life cycle schema and considering its relationship to a range of indicators of social exclusion. At the European level renewed interest in the life cycle concept is associated with the increasing emphasis on the distinction between "new" and "old" social risks and the notion that the former are more "individualised". Inequality and poverty rather than being differentially distributed between social classes are thought to vary between phases in the average work life. Our findings suggest the "death of social class" thesis is greatly overblown. A more accurate appreciation of the importance of new and old social risks requires that we systematically investigate the manner in which factors such as social class and the life cycle interact.
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In any internal combustion engine, the amount of heat rejected from the engine, and associated systems, is a result of the engine inefficiency. Successfully recovering a small proportion of this energy would therefore substantially improve the fuel economy.
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Research on fusion fast ignition (FI) initiated by laser-driven ion beams has made substantial progress in the last years. Compared with electrons, FI based on a beam of quasi-monoenergetic ions has the advantage of a more localized energy deposition, and stiffer particle transport, bringing the required total beam energy close to the theoretical minimum. Due to short pulse laser drive, the ion beam can easily deliver the 200 TW power required to ignite the compressed D-T fuel. In integrated calculations we recently simulated ion-based FI targets with high fusion gain targets and a proof of principle experiment [1]. These simulations identify three key requirements for the success of ion-driven fast ignition (IFI): (1) the generation of a sufficiently high-energetic ion beam (approximate to 400-500 MeV for C), with (2) less than 20% energy spread at (3) more than 10% conversion efficiency of laser to beam energy. Here we present for the first time new experimental results, demonstrating all three parameters in separate experiments. Using diamond nanotargets and ultrahigh contrast laser pulses we were able to demonstrate >500 MeV carbon ions, as well as carbon pulses with Delta E/E
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Energy release from radioactive decays contributes significantly to supernova light curves. Previous works, which considered the energy deposited by ?-rays and positrons produced by Ni, Co, Ni, Co, Ti and Sc, have been quite successful in explaining the light curves of both core collapse and thermonuclear supernovae. We point out that Auger and internal conversion electrons, together with the associated X-ray cascade, constitute an additional heat source. When a supernova is transparent to ?-rays, these electrons can contribute significantly to light curves for reasonable nucleosynthetic yields. In particular, the electrons emitted in the decay of Co, which are largely due to internal conversion from a fortuitously low-lying 3/2 state in the daughter Fe, constitute an additional significant energy-deposition channel. We show that when the heating by these electrons is accounted for, a slow-down in the light curve of SN 1998bw is naturally obtained for typical hypernova nucleosynthetic yields. Additionally, we show that for generic Type Ia supernova yields, the Auger electrons emitted in the ground-state to ground-state electron capture decay of Fe exceed the energy released by the Ti decay chain for many years after the explosion. © 2009 RAS.
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Key stakeholders in the UK charity sector have, in recent years, advocated greater accountability for charity performance. Part of that debate has focussed on the use of conversion ratios as indicators of efficiency, with importance to stakeholders being contrasted with charities’ apparent reluctance to report such measures. Whilst, before 2005, conversion ratios could have been computed from financial statements, changes in the UK charity SORP have radically altered the ability of users to do this. This article explores the impact on the visibility of such information through an analysis of the financial statements of large UK charities before and after the 2005 changes. Overall, the findings suggest that, despite the stated intention of increasing transparency in respect of charity costs, the application of the changes has resulted in charities ‘managing’ the numbers and limiting their disclosures, possibly to the detriment of external stakeholders.
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Two porous metal organic frameworks (MOFs), [M-2(C8H2O6)(H2O)(2)] center dot 8H(2)O (M = Co, Ni), perform exceptionally well for the adsorption, storage, and water-triggered delivery of the biologically important gas nitric oxide. Adsorption and powder X-ray diffraction studies indicate that each coordinatively unsaturated metal atom in the structure coordinates to one NO molecule. All of the stored gas is available for delivery even after the material has been stored for several months. The combination of extremely high adsorption capacity (similar to 7 mmol of NO/g of MOF) and good storage stability is ideal for the preparation of NO storage solids. However, most important is that the entire reservoir of stored gas is recoverable on contact with a simple trigger (moisture). The activity of the NO storage materials is proved in myography experiments showing that the NO-releasing MOFs cause relaxation of porcine arterial tissue.
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This paper is concerned with assessing the building’s the energy efficiency and qualities of a modular design for the education industry, in order assess the long economic benefits. The research includes a life-cycle energy and cost analysis of the school building design, predicting the impact on the operational cost of the building as a result of the addition of photovoltaic panels. The paper also includes a comparative study between the ECO Modular Solutions building, and a current standard prefabricated school building, quantifying the savings in CO2 emissions and savings in cost.
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The commercial production of vanillin from sodium lignosulfonate under highly alkaline conditions, catalyzed by Cu2+ at elevated temperature and pressures up to 10 bar, has been simulated in a 3-L stirred reactor. Initially, the process was operated in the presence of nitrogen in dead-end mode, and it was shown that vanillin and vanillic acid were formed by hydrolysis at temperatures of 120, 140, and 160 °C. At the two higher temperatures, the amount of vanillin produced was the same. Subsequently, experiments were conducted at the same elevated pressures and temperatures with addition of air or oxygen-enriched air once the temperature in the reactor had reached temperatures similar to those used when only hydrolysis occurred. In this case, the concentration of vanillin at 140 and 160 °C was equal to that due to hydrolysis, and the subsequent 2-fold increase was due to oxidation. In addition, both vanillic acid and acetovanillone (which has rarely been reported) were produced, as was hydrogen. Thus, for the first time, it has been shown that the production of vanillin (and other compounds) from sodium lignosulfonate at elevated temperatures involves hydrolysis and oxidation, with hydrolysis starting at just above 100 °C, that is, much lower than has previously been reported. Approximately 50% is produced by each mechanism. In addition, the orders of the reactions of the different steps were estimated, and the reaction mechanisms are discussed.
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Cell division depends on the fine control of both microtubule dynamics and microtubule organisation. The microtubule bundling protein MAP65 is a 'midzone MAP' essential for the integrity of the anaphase spindle and cell division. Arabidopsis thaliana MAP65-1 (AtMAP65-1) binds and bundles microtubules by forming 25 nm cross-bridges. Moreover, as AtMAP65-1 bundles microtubules in interphase, anaphase and telophase but does not bind microtubules in prophase or metaphase, its activity through the cell cycle must be under tight control. Here we show that AtMAP65-1 is hyperphosphorylated during prometaphase and metaphase and that CDK and MAPK are involved in this phosphorylation. This phosphorylation inhibits AtMAP65-1 activity. Expression of nonphosphorylatable AtMAP65-1 has a negative effect on mitotic progression resulting in excessive accumulation of microtubules in the metaphase spindle midzone causing a delay in mitosis. We conclude that normal metaphase spindle organisation and the transition to anaphase is dependent on inactivation of AtMAP65-1.
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S-(2-Succinyl)cysteine (2SC) has been identified as a chemical modification in plasma proteins, in the non-mercaptalbumin fraction of human plasma albumin, in human skin collagen, and in rat skeletal muscle proteins and urine. 2SC increases in human skin collagen with age and is increased in muscle protein of diabetic vs. control rats. The concentration of 2SC in skin collagen and muscle protein correlated strongly with that of the advanced glycation/lipoxidation end-product (AGE/ALE), N(epsilon)-(carboxymethyl)lysine (CML). 2SC is formed by a Michael addition reaction of cysteine sulfhydryl groups with fumarate at physiological pH. Fumarate, but not succinate, inactivates the sulfhydryl enzyme, glyceraldehyde-3-phosphate dehydrogenase in vitro, in concert with formation of 2SC. 2SC is the first example of spontaneous chemical modification of protein by a metabolic intermediate in the Krebs cycle. These observations identify fumarate as an endogenous electrophile and suggest a role for fumarate in regulation of metabolism.
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The recent adiabatic saddle-point approach of Shearer et al. [ Phys. Rev. A 84 033409 (2011)] is extended to multiphoton detachment of negative ions with outer p-state electrons. This theory is applied to investigate the strong-field photodetachment dynamics of F- ions exposed to few-cycle femtosecond laser pulses, without taking into account the rescattering mechanism. Numerical calculations are considered for mid-infrared laser wavelengths of 1300 and 1800 nm at laser intensities of 7.7 × 1012, 1.1 × 1013, and 1.3 × 1013 W/cm2. Two-dimensional momenta saddle-point spectra exhibit a distinct distribution in the shape of a “smile” in the complex-time plane. Electron momentum distribution maps of direct electrons are investigated. These produce a distinct pattern of above-threshold detachment (ATD) concentric rings due to constructive and destructive quantum interference of electrons detached from their parent ions. Probability detachment distributions presented, capturing the influence of saturation effects that are found to become more significant with increasing laser intensity at a fixed wavelength. ATD photoangular distributions as functions of laser intensity and wavelength near channel closings are also investigated and found to be sensitive to initial-state symmetry. Nonmonotonic structures observed in the ejected photoelectron energy spectra are attributed to interference effects from coherent electronic wave packets. Additionally the profiles of all the photoelectron emission spectra show strong dependence on the carrier-envelope phase, indicating that it is a reliable parameter for characterizing the wave form of the pulse.