5,607 research outputs found
Required Rates of Return for Corporate Investment Appraisal in the Presence of Growth Opportunities
Traditional methods of estimating required rates of return overstate hurdle rates in the presence of growth opportunities. We attempt to quantify this effect by developing a simple model which: (i) identifies those companies that have valuable growth opportunities; (ii) splits the value of shares into 'assets-in-place' and 'growth opportunities'; and (iii) splits the equity β into β for 'assets-in-place' and 'growth opportunities'. We find growth opportunities for UK companies over the 1990–2004 period to average 33% of equity value. Incorporating the effect of growth opportunities, the average cost of capital for investment purposes falls by 1.1 percentage points
Single-particle measurements of filamentous influenza virions reveal damage induced by freezing
Clinical isolates of influenza virus produce pleiomorphic virions, ranging from small spheres to elongated filaments. The filaments are seemingly adaptive in natural infections, but their basic functional properties are poorly understood and functional studies of filaments often report contradictory results. This may be due to artefactual damage from routine laboratory handling, an issue which has been noted several times without being explored in detail. To determine whether standard laboratory techniques could damage filaments, we used immunofluorescence microscopy to rapidly and reproducibly quantify and characterize the dimensions of filaments. Most of the techniques we tested had minimal impact on filaments, but freezing to −70 °C, a standard storage step before carrying out functional studies on influenza viruses, severely reduced their concentration, median length and the infectivity of the whole virion population. We noted that damage from freezing is likely to have affected most of the functional studies of filaments performed to date, and to address this we show that it can be mitigated by snap-freezing or incorporating the cryoprotectant DMSO. We recommend that functional studies of filaments characterize virion populations prior to analysis to ensure reproducibility, and that they use unfrozen samples if possible and cryoprotectants if not. These basic measures will support the robust functional characterizations of filaments that are required to understand their roles in natural influenza virus infections
The B subunit of Escherichia coli heat-labile toxin alters the development and antigen-presenting capacity of dendritic cells
Escherichia coli’s heat-labile enterotoxin (Etx) and its non-toxic B subunit (EtxB) have been characterized as adjuvants capable of enhancing T cell responses to co-administered antigen. Here, we investigate the direct effect of intravenously administered EtxB on the size of the dendritic and mye-loid cell populations in spleen. EtxB treatment appears to enhance the development and turnover of dendritic and myeloid cells from precursors within the spleen. EtxB treatment also gives a dendritic cell (DC) population with higher viability and lower activation status based on the reduced expression of MHC-II, CD80 and CD86. In this respect, the in vivo effect of EtxB differs from that of the highly inflammatory mediator lipopolysaccharide. In in vi-tro bone marrow cultures, EtxB treatment was also found to enhance the development of DC from precursors dependent on Flt3L. In terms of the in vivo effect of EtxB on CD4 and CD8 T cell responses in mice, the interaction of EtxB directly with DC was demonstrated following conditional deple-tion of CD11c+ DC. In summary, all results are consistent with EtxB displaying adjuvant ability by enhancing the turnover of DC in spleen, leading to newly mature myeloid and DC in spleen, thereby increasing DC capacity to perform as antigen-presenting cells on encounter with T cells
Bulletin No. 125 - The Chemical Milling and Bake Value of Utah Wheats
The Chemical Department of the Utah Experiment Station, since 1903, has been conducting investigations regarding the value of different wheats grown in the State. The results obtained during the years 1903 to 1906 were published as Bulletin No. 103 of this station. A special investigation in 1910 regarding the influence of the combined harvester on the value of the wheat was conducted and the results obtained issued as Bulletin No. 113. The results reported in the following pages were obtained during the progress of these investigations during the years 1907, 1908, and 1909. The method of milling the samples of wheat are essentially the same as previously reported.* The samples of wheat were all cleaned by the scrubber as indicated in the previous report. The methods of analysis are similar to the ones described in the former bulletins. The determinations for gliadin and glutenin are not reported because considerable energy has been expended on perfecting a better method of determining the gliadin content of the flour. The results of this special investigation have been published by Dr. Greaves. The determination. of the acidity of the flour has also been omitted. Before any valuable information can be obtained from this factor, it is necessary to make a complete study of the methods of determination. Such a study will be taken up at this laboratory. The volumetric method as reported in the former bulletin has no value
ciliaFA : a research tool for automated, high-throughput measurement of ciliary beat frequency using freely available software
Background: Analysis of ciliary function for assessment of patients suspected of primary ciliary dyskinesia (PCD) and
for research studies of respiratory and ependymal cilia requires assessment of both ciliary beat pattern and beat
frequency. While direct measurement of beat frequency from high-speed video recordings is the most accurate and
reproducible technique it is extremely time consuming. The aim of this study was to develop a freely available
automated method of ciliary beat frequency analysis from digital video (AVI) files that runs on open-source software
(ImageJ) coupled to Microsoft Excel, and to validate this by comparison to the direct measuring high-speed video
recordings of respiratory and ependymal cilia. These models allowed comparison to cilia beating between 3 and 52 Hz.
Methods: Digital video files of motile ciliated ependymal (frequency range 34 to 52 Hz) and respiratory epithelial cells
(frequency 3 to 18 Hz) were captured using a high-speed digital video recorder. To cover the range above between 18
and 37 Hz the frequency of ependymal cilia were slowed by the addition of the pneumococcal toxin pneumolysin.
Measurements made directly by timing a given number of individual ciliary beat cycles were compared with those
obtained using the automated ciliaFA system.
Results: The overall mean difference (± SD) between the ciliaFA and direct measurement high-speed digital imaging
methods was −0.05 ± 1.25 Hz, the correlation coefficient was shown to be 0.991 and the Bland-Altman limits of
agreement were from −1.99 to 1.49 Hz for respiratory and from −2.55 to 3.25 Hz for ependymal cilia.
Conclusions: A plugin for ImageJ was developed that extracts pixel intensities and performs fast Fourier
transformation (FFT) using Microsoft Excel. The ciliaFA software allowed automated, high throughput measurement of
respiratory and ependymal ciliary beat frequency (range 3 to 52 Hz) and avoids operator error due to selection bias. We
have included free access to the ciliaFA plugin and installation instructions in Additional file 1 accompanying this
manuscript that other researchers may use
Bulletin No. 147 - The Alkali Content of Irrigation Water
In certain irrigated districts the alkali problem is a menace. Any controllable factor which tends to increase the alkali content of the soil should be carefully considered in a successful system of soil management. In this connection the quality of the irrigation water is of great importance; the saline content of water has a marked influence upon the method and quantity to be used for irrigation. The factors which will contribute to an increase or decrease of the alkali content of the water must be clearly understood. The amount of the several kinds of alkali salts added to the soil by large or small applications of water must be clearly understood in order that the farmer may utilize the water supply to the best advantage. A knowledge of the quantity and nature of the alkali salts added to the soil will enable him to more systematically plan his crop rotation since crops vary in their power to resist the action of the several kinds of alkali
Magnetic anisotropy of asbestos fibres
Original article can be found at : http://jap.aip.org/jap/ Copyright American Institute of PhysicsThe anisotropy of magnetic susceptibility of single asbestos fibers is measured. The alignment of both chrysotile and crocidolite fibers in magnetic fields is found to be due to the anisotropy. The average measured anisotropy of volume susceptibility is 0.40×10−6 for chrysotile and 83×10−6 for crocidolite. Fiber shape effects are estimated to contribute, on average, about 10% and 6%, respectively, to the total anisotropy of the two types of fiber. There is no evidence of significant permanent magnetic moments. The magnitude of the observed alignment makes the effect potentially useful in real-time detection of airborne asbestos fibers. The experimental technique developed in the study can be used for measuring the anisotropy of small particles of well-defined shape. High sensitivity of the technique permits the measurement of torques lower than 10−21 Nm on particles down to picogram mass.Peer reviewe
The use of informal resolution approaches by ombudsmen in the UK and Ireland: A mapping study
This report presents findings of an empirical research project, funded by the Nuffield Foundation, designed to produce a descriptive mapping study on the use of informal resolution by ombudsmen. Its focus is on the use of informal resolution approaches as alternatives to investigation and determination/decision.
The use of informal and early resolution techniques by ombudsmen and other complaint handlers is an under-studied area but one which is gaining importance in light of several developments in the field of administrative justice generally, and the European Union ADR Directive, to be implemented by 2015. This directive looks set to overhaul complaint handling in the private sector by requiring the government to ensure that an ADR scheme is available in all contractual disputes between a consumer and a business (although neither consumer nor business will be obliged to use the service).
This report sets out the analysis of the responses received from 48 ombudsman and complaint-handling organisations in UK and Ireland that are (or were at the relevant time) members of the Ombudsman Association
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