Measurements of the Secondary Electron Emission from Rare Gases at 4.2K

Dependence of the secondary electron yield (SEY) from the primary beam incident energy and the coverage has been measured for neon, argon, krypton and xenon condensed on a target at 4.2K. The beam energy ranged between 100 eV and 3 keV, the maximal applied coverage have made up 12000, 4700, 2500 and 1400 monolayers correspondingly for neon, argon, krypton and xenon. The SEY results for these coverages can be considered as belonging only to investigated gases without influence of the target material. The SEY dependencies versus the primary beam energy for all gases comprise only an ascending part and therefore, the maximal measured SEY values have been obtained for the beam energy of 3keV and have made up 62, 73, 60.5 and 52 for neon, argon, krypton and xenon correspondingly. Values of the first cross-over have made up 21 eV for neon, 14 eV for argon, 12.5 eV for krypton and 10.5 eV for xenon. An internal field appearing across a film due to the beam impact can considerably affect the SEY measurements that demanded the beam current to be reduced till 9.0E-10A. Duration of the beam impact varied between 500 \mu sec and 250 \mu sec. It was found that reliable SEY measurements can also be taken on a charged surface if the charge was acquired due to beam impact with electrons of higher energy. All SEY measurements for once applied coverage have been carried out for whole range of incident energies from 3 keV down to 100 eV without renewing the film. Developing of pores inside of a deposited film can significantly increase the SEY as it was observed during warming up the target.Comment: 10 Pages - 25 figure

Measurements of the Secondary Electron Emission of Some Insulators

Charging up the surface of an insulator after beam impact can lead either to reverse sign of field between the surface and collector of electrons for case of thick sample or appearance of very high internal field for thin films. Both situations discard correct measurements of secondary electron emission (SEE) and can be avoided via reducing the beam dose. The single pulse method with pulse duration of order of tens microseconds has been used. The beam pulsing was carried out by means of an analog switch introduced in deflection plate circuit which toggles its output between "beam on" and "beam off" voltages depending on level of a digital pulse. The error in measuring the beam current for insulators with high value of SEE was significantly reduced due to the use for this purpose a titanium sample having low value of the SEE with DC method applied. Results obtained for some not coated insulators show considerable increase of the SEE after baking out at 3500C what could be explained by the change of work function. Titanium coatings on alumina exhibit results close to the ones for pure titanium and could be considered as an effective antimultipactor coating.Comment: 8 pages, 13 figure

Measurement Issues in Assessing Farm Profitability through Cash Tax Returns

It is widely accepted that net farm income reported on an accrual-adjusted income statement is a more appropriate profitability measure than net farm income reported on Schedule F of the federal tax return, which is prepared using cash basis accounting. However, a common practice among agricultural lenders is to use Schedule F net farm income, which uses the cash basis of accounting, as a proxy for accrual-adjusted net farm income. A study of 1,045 individual Illinois farms’ records from 2002 through 2006 found the median absolute annual percentage difference between a three-year average cash and a three-year average accrual-adjusted net farm incomes is 57 percent for farms of stable size; 43 percent for farms with annual gross revenue increasing at rates of less than 5 percent, 50 percent at rates of 5-10 percent, and 58 percent at rates over 10 percent; and 61 percent for farms with a debt-to-asset ratio greater than 40 percent.Agricultural Finance,

Systems, interactions and macrotheory

A significant proportion of early HCI research was guided by one very clear vision: that the existing theory base in psychology and cognitive science could be developed to yield engineering tools for use in the interdisciplinary context of HCI design. While interface technologies and heuristic methods for behavioral evaluation have rapidly advanced in both capability and breadth of application, progress toward deeper theory has been modest, and some now believe it to be unnecessary. A case is presented for developing new forms of theory, based around generic “systems of interactors.” An overlapping, layered structure of macro- and microtheories could then serve an explanatory role, and could also bind together contributions from the different disciplines. Novel routes to formalizing and applying such theories provide a host of interesting and tractable problems for future basic research in HCI

Preparation Methods for Quantitative Electron Probe X-Ray Microanalysis of Rat Exocrine Pancreas: A Review

Pancreatic acinar cells are thought to secrete a fluid containing digestive enzymes and electrolytes and use e,g, calcium as a second messenger upon stimulation, Together with their pronounced morphological polarity, they provide a model system to study the effect of different preparation methods for quantitative biological electron probe X-ray microanalysis (EPXMA) of ultrathin sections, Several preparation methods i,e,, freeze-drying and plastic-embedding, freeze-substitution (2 days) and freeze-drying of ultrathin cryosections have been applied to examine the retention of sodium, magnesium, phosphorus, sulfur, (chlorine), potassium and calcium in subcellular compartments (basal cytoplasm, apical cytoplasm, mitochondria and zymogen granules), In freeze-substituted samples the phosphorus, potassium and sulfur concentrations were 2-3 times lower in all compartments compared to freeze-dried, plastic-embedded samples, Intracellular potassium-to-sodium ratios obtained on frozen substituted and frozen-dried, plastic-embedded samples were considerably lower than for cryosections, Element gradients between adjacent organelles were large in frozen-dried cryosections, smaller in frozen-dried plastic-embedded samples and insignificant in frozen-substituted samples

An analysis of income tax implications from the transfer of soccer players

Abstract: Sports clubs often trade in players with each other through the player transfer system. Using the doctrinal research methodology, the study aims at providing an interpretative analysis of the income tax implications from transfer of professional soccer players between professional soccer clubs, based on the Income Tax Act 58 of 1962 (South Africa, 1962) (hereafter the Act)and the relevant case law. The research methodology used is the doctrinal research methodology which involved an extended review of literature. This article concludes whether the transfer fees arising from the transfer of soccer players should be included in the gross income or be subject to capital gains tax in determining the taxable income of the transferor club. In addition, the study also determines whether the transferee club can deduct the transfer fees in respect of the transfer fees paid in acquisition of player rights under s 11(a) of the Act

Income tax implications from the transfer of soccer players in South Africa

Abstract: Sports clubs often trade players with each other through the player transfer system. Using the doctrinal research methodology, which involves an extended review of literature, the study aims at providing an interpretative analysis of the income tax implications from the transfer of professional soccer players between professional soccer clubs, based on the Income Tax Act 58 of 1962 (South Africa, 1962) (hereafter the Act) and the relevant case law. This study further provides hypothetical case studies that provide different scenarios of soccer player transfers and the analysis of the income tax implications arising from the facts presented in each case study

Measurement of the dependence of the light yields of linear alkylbenzene-based and EJ-301 scintillators on electron energy

An experimental test of the electron energy scale linearities of SNO+ and EJ-301 scintillators was carried out using a Compton spectrometer with electrons in the energy range 0.09-3 MeV. The linearity of the apparatus was explicitly demonstrated. It was found that the response of both types of scintillators with respect to electrons becomes non-linear below ~0.4 MeV. An explanation is given in terms of Cherenkov light absorption and re-emission by the scintillators.Comment: 8 pages, 7 figure

Detection of Vibrio cholerae O1 in animal stools collected in rural areas of the Limpopo Province

Vibrio cholerae (V. cholerae), the causative agent of cholera, has been responsible for various outbreaks worldwide and may be associated with animal faeces. In an attempt to understand the occurrence of this organism in the environment, 230 faecal samples were collected from pigs, chickens, goats, donkeys, cows and pigeons in rural areas of the Limpopo Province. Bacterial DNA was extracted from the faecal samples using a guanidium thiocyanate-based method. The DNA was screened for the presence of the sodB, rfb, FlaE, 16S rRNA and ctxA genes associated with V. cholerae, V. cholerae O1, V. cholerae O139 using 2 multiplex polymerase chain reactions (m-PCR). The V. cholerae sodB gene was detected in 74 of the 230 samples tested. Detection rates for the faecal samples obtained from individual species were as follows: cows (55/74), chickens (8/74), goats (2/74), donkeys (4/74), pigs (3/74) and pigeons (2/74). V. cholerae O1 was detected in (17/74) cow and (3/74) chicken samples, of which (9/17) cow samples and (3/3) chicken samples tested positive for toxigenic V. cholerae O1. The presence of this organism in faecal samples, taken close to water sources used by the villagers, raises the possibility that the causative V. cholerae O1 strain of the most recent outbreak in South Africa was present in the area 6 months prior to the outbreak.Keywords: Vibrio cholerae, PCR, animal faeces, cholera toxi