A Microcomputer-Based Data Acquisition System with Hardware Capabilities to Calculate a Fast Fourier Transform

The Fast Fourier Transform (FFT) Has in Recent Years Become an Important Tool to the Engineer. There Are a Number of Algorithms Which Calculate the FFT. One Such Algorithm is the Cooley-Tukey FFT Algorithm (Radix-2) Which Lends itself Rather Easily to a Combination Software and Hardware Implementation. with a Microcomputer as the Controller of a Data Acquisition Module and Hardware Which Computes the Butterfly Associated with the FFT Algorithm, the FFT Can Be Calculated Efficiently. © 1979 IEE

Simulating Heliospheric and Solar Particle Diffusion using the Parker Spiral Geometry

Cosmic Ray transport in curved background magnetic fields is investigated using numerical Monte-Carlo simulation techniques. Special emphasis is laid on the Solar system, where the curvature of the magnetic field can be described in terms of the Parker spiral. Using such geometries, parallel and perpendicular diffusion coefficients have to be re-defined using the arc length of the field lines as the parallel displacement and the distance between field lines as the perpendicular displacement. Furthermore, the turbulent magnetic field is incorporated using a WKB approach for the field strength. Using a test-particle simulation, the diffusion coefficients are then calculated by averaging over a large number of particles starting at the same radial distance from the Sun and over a large number of turbulence realizations, thus enabling one to infer the effects due to the curvature of the magnetic fields and associated drift motions.Comment: accepted for publication at Journal of Geophysical Research - Space Physic

In vitro activity of ivermectin against Staphylococcus aureus clinical isolates

Background Ivermectin is an endectocide against many parasites. Though being a macrocyclic lactone, its activity against bacteria has been less known, possibly due to the fact that micromolar concentrations at tissue levels are required to achieve a therapeutic effect. Among pathogenic bacteria of major medical significance, Staphylococcus aureus cause a number of diseases in a wide variety of hosts including humans and animals. It has been attributed as one of the most pathogenic organisms. The emergence of methicillin resistance has made the treatment of S. aureus even more difficult as it is now resistant to most of the available antibiotics. Thus, search for alternate anti-staphylococcal agents requires immediate attention. Methods Twenty-one clinical isolates of S. aureus were isolated from bovine milk collected from Lahore and Faisalabad Pakistan. Different anthelmintics including levamisole, albendazole and ivermectin were tested against S. aureus to determine their minimum inhibitory concentrations. This was followed-up by growth curve analysis, spot assay and time-kill kinetics. Results The results showed that ivermectin but not levamisole or albendazole exhibited a potent anti-staphylococcal activity at the concentrations of 6.25 and 12.5 μg/ml against two isolates. Interestingly, one of the isolate was sensitive while the other was resistant to methicillin/cefoxitin. Conclusions Our novel findings indicate that ivermectin has an anti-bacterial effect against certain S. aureus isolates. However, to comprehend why ivermectin did not inhibit the growth of all Staphylococci needs further investigation. Nevertheless, we have extended the broad range of known pharmacological effects of ivermectin. As pharmacology and toxicology of ivermectin are well known, its further development as an anti-staphylococcal agent is potentially appealing

Estimating Contact Process Saturation in Sylvatic Transmission of Trypanosoma cruzi in the United States

Although it has been known for nearly a century that strains of Trypanosoma cruzi, the etiological agent for Chagas' disease, are enzootic in the southern U.S., much remains unknown about the dynamics of its transmission in the sylvatic cycles that maintain it, including the relative importance of different transmission routes. Mathematical models can fill in gaps where field and lab data are difficult to collect, but they need as inputs the values of certain key demographic and epidemiological quantities which parametrize the models. In particular, they determine whether saturation occurs in the contact processes that communicate the infection between the two populations. Concentrating on raccoons, opossums, and woodrats as hosts in Texas and the southeastern U.S., and the vectors Triatoma sanguisuga and Triatoma gerstaeckeri, we use an exhaustive literature review to derive estimates for fundamental parameters, and use simple mathematical models to illustrate a method for estimating infection rates indirectly based on prevalence data. Results are used to draw conclusions about saturation and which population density drives each of the two contact-based infection processes (stercorarian/bloodborne and oral). Analysis suggests that the vector feeding process associated with stercorarian transmission to hosts and bloodborne transmission to vectors is limited by the population density of vectors when dealing with woodrats, but by that of hosts when dealing with raccoons and opossums, while the predation of hosts on vectors which drives oral transmission to hosts is limited by the population density of hosts. Confidence in these conclusions is limited by a severe paucity of data underlying associated parameter estimates, but the approaches developed here can also be applied to the study of other vector-borne infections

Creating regional policy system of rural areas development in Western Pomerania

W opracowaniu przedstawiono założenia polityki regionalnej, ze szczególnym uwzględnieniem koncepcji restrukturyzacji gospodarstw rodzinnych na Pomorzu Zachodnim. Uwzględniono warunki transformacji rolnictwa do 2000 roku, w tym założenia polityki rolnej i etapy transformacji, przewidywane przemiany strukturalne, regionalny program rozwoju rolnictwa (charakterystykę makroregionu, analizę stanu i warunki rozwoju rolnictwa, koncepcję przestrzennej polityki regionalnej, proces przebudowy struktury własnościowej). Wysunięto hipotezę, że zaproponowane kierunki przemian i aktywizacji rolniczej przestrzeni produkcyjnej na Pomorzu Zachodnim są właściwe, a przedstawiony poziom rozwoju możliwy do osiągnięcia w prognozowanym okresie.Paper presents the presumptions of regional policy with special emphasis on restructuring family farms in Western Pomerania. Agriculture transformation conditions until 2000 were considered including the postulates of agricultural policy and transformation stages, expected structural changes and regional program of agriculture development (macro- region characteristics, analysis of state and conditions of agricultural development, conception of spatial regional policy, process of rebuilding ownership structure). The hypothesis was put forward that the proposed directions of changes and activation of agricultural production sphere in Western Pomerania are really suitable and presented developing level is attainable within provided period

Role of agricultural advisory in restructurization of agriculture in Western Pomerania

Dokonujący się proces transformacji obszarów wiejskich w Polsce do nowych realiów ustrojowych, a także do warunków funkcjonowania w ramach integracji z Unią Europejską, wymaga odmiennego podejścia do sposobu restrukturyzacji i modernizacji gospodarstw rodzinnych, a także roli systemu doradztwa rolniczego w rozwiązywaniu tych problemów. W opracowaniu przedstawiono rolę doradztwa w przemianach wsi i rolnictwa, funkcjonowanie systemu doradztwa rolniczego, udziału doradztwa w procesach restrukturyzacji rolnictwa, regionalne modelowanie doradztwa, rolę doradców i analizę stanu i warunków rozwoju systemu doradztwa rolniczego w Polsce.Occuring in Poland process of rural areas transformation to the realities of new economic system as well as the adaptation to conditions of mctioning within the integration to the European Union, need the new pproach to restructuring and modernization of family farms and to the rolе of agricultural advisory system in respect of solving these problems. The paper discussed the role of advisory system in country and agriultural transformation, functioning of agricultural advisory system, parcipation of the advisory in farming restructurization processes, modelling egional advisory, role of advisors and analysis of the state and conditions f development agricultural advisory system in Poland

Model and system conception of agricultural advisory in the Western Pomerania

W sterowaniu przemianami strukturalnymi i własnościowymi w rolnictwie w każdym województwie (regionie) niezbędna jest znajomość przestrzennego zróżnicowania czynników produkcji Wraz z diagnozą potencjału ekonomicznego. Zmiany rozwoju rolnictwa przebiegają dynamicznie, szczególnie zaś technologia, otoczenie rolnictwa, finansowanie oraz rynek rolny. Istotnym elementem tego systemu jest organizacja doradztwa rolniczego. Niezbędne jest zatem wyodrębnienie regionalnego modelu doradztwa, który byłby typowy, specyficzny i dopasowany do realiów ekonomiczno-produkcyjnych oraz strukturalnych każdego z województw lub grupy województw tworzących region. Powstaje zatem model regionalnego doradztwa, specyficzny dla każdego obszaru kraju. W regionalnym modelu doradztwa rolniczego na Pomorzu Zachodnim główne miejsce zajmuje problem restrukturyzacji gospodarstw państwowych. Otoczenie rolnictwa ma tutaj szczególnie duży wpływ na kształt i efektywność tego modelu.In process of steering structural and ownership changes in agriculture in each province (region) the knowledge of production factors and their spatial differentiations together with diagnosis of the economic potential are necessary. The changes in agricultural development run dynami-cally, especially regarding technology, agricultural environment, financing and agricultural market. Organizing agricultural advisory is a significant element of the system. It is necessary to separate a regional model of advisory which would be typical, specific and fitted to economic- production and structural realities of every province or the group of provinces that build the region. The model of regional agricultural advisory, specific for every area in the country is created. The topic problem for regional agricultural advisory, specific in the Western Pomerania is the restructurization of state farms. The environment of agriculture affects the shape and effectiveness of that model