Electron microscopy and the investigation of new infectious diseases

AbstractObjectives: To review and assess the role of electron microscopy in the investigation of new infectious diseases.Design: To design a screening strategy to maximize the likelihood of detecting new or emerging pathogens in clinical samples.Results: Electron microscopy remains a useful method of investigating some viral infections (infantile gastroenteritis, virus-induced outbreaks of gastroenteritis and skin lesions) using the negative staining technique. In addition, it remains an essential technique for the investigation of new and emerging parasitic protozoan infections in the immunocompromised patients from resin-embedded tissue biopsies. Electron microscopy can also have a useful role in the investigation of certain bacterial infections.Conclusions: Electron microscopy still has much to contribute to the investigation of new and emerging pathogens, and should be perceived as capable of producing different, but equally relevant, information compared to other investigative techniques. It is the application of a combined investigative approach using several different techniques that will further our understanding of new infectious diseases

MONOPSONY POWER IN MULTIPLE INPUT MARKETS: A Nonparametric Approach

Cigarette manufacturers' monopsony power exertion in procuring domestic and imported tobacco is investigated using nonparametric methods. While it is often assumed that tobacco program rents are captured by growers, results indicate the opposite actually occurs. Cigarette manufacturers appear to exert significant monopsony power in the domestic leaf tobacco market and capture a large portion of program rents. Cigarette manufacturers appear to exert monopsony power of much smaller magnitude in the international leaf tobacco market, but with increasing magnitude in more recent years.market power, tobacco, nonparametric, monopsony, imports., International Relations/Trade, L1,

DISTINGUISHING THE SOURCE OF MARKET POWER: AN APPLICATION TO CIGARETTE MANUFACTURING

We compare nonparametric and nonstructural market power tests using data from the cigarette manufacturing industry. Tests are implemented to examine both monopoly and monopsony power exertion by cigarette manufacturers. Results indicate that market power in the tobacco industry, previously attributed to monopoly power exertion, should at least in part be attributed to monopsony market power in the upstream tobacco market.market power, nonparametric, nonstructural, monopsony, monopoly, cigarette manufacturing, Agribusiness,

Sustainable IT at Intel: A Teaching Case

Sustainable IT involves the responsible management of resources (both IT and non-IT) encompassing environmental, economic, and social dimensions. Sustainable IT has the potential to be a significant contributor to an organizations sustainability strategy. In this teaching case, we examine what Intel IT has done to transform its operations with Sustainable IT, resulting in the avoidance of significant CO2 emissions and cost savings. This teaching case challenges the reader to analyze the Sustainable IT capability at Intel. The case includes insights into strategic and operational challenges of planning and managing Sustainable IT

Rangeland surveys : a basis for improved land use

In mis 1988, the Department of Agriculture started a three-year programme to assist pastoralists in the Murchison River catchment to update land management planning of their stations. This Project, which is funded by the National Soil Conservation Program, will use interim results from a recent rangeland survey which has investigated and mapped the grazing recources throughout the region. Elsewhere in Western Australia\u27s pastoral areas, information on the productive potential of each area - and the management problems inherent for each class of land - are being used to help pastoral managers of Soil Conservation Districts rehabilitate degraded areas. This information will also encourage them to adopt management practices that conserve the land and improve the long-term economic performance of the grazing enterprise

The Changing Environment of Urban Development Policy—Shared Power or Shared Impotence?

In this Article we highlight five recent trends that have profoundly transformed the shared power system of American urban government as it relates to that arena of urban development in which we have been active over the past half-dozen years: transportation

Evaluating the relationship between impervious surfaces within watersheds and coastal water quality on Virginia’s Eastern Shore

The overall objective of this research is to determine the relationship between the percent of a watershed covered by impervious surfaces and water quality in tidal creeks on the Eastern Shore of Virginia in an effort to provide local governments and citizens guidance in developing zoning plans. Our specific objectives were to: (1) Determine the relationships between percent impervious surface in a watershed and concentrations of suspended sediments, nitrogen, phosphorus, chlorophyll a and fecal coliform bacteria in tidal creek headwaters; (2) Examine these relationships with and without the inclusion of tomato cultivation to determine whether it should be included in the determination of percent impervious surface within a watershed

Collapse and Fragmentation of Molecular Cloud Cores. X. Magnetic Braking of Prolate and Oblate Cores

The collapse and fragmentation of initially prolate and oblate, magnetic molecular clouds is calculated in three dimensions with a gravitational, radiative hydrodynamics code. The code includes magnetic field effects in an approximate manner: magnetic pressure, tension, braking, and ambipolar diffusion are all modelled. The parameters varied for both the initially prolate and oblate clouds are the initial degree of central concentration of the radial density profile, the initial angular velocity, and the efficiency of magnetic braking (represented by a factor $f_{mb} = 10^{-4}$ or $10^{-3}$). The oblate cores all collapse to form rings that might be susceptible to fragmentation into multiple systems. The outcome of the collapse of the prolate cores depends strongly on the initial density profile. Prolate cores with central densities 20 times higher than their boundary densities collapse and fragment into binary or quadruple systems, whereas cores with central densities 100 times higher collapse to form single protostars embedded in bars. The inclusion of magnetic braking is able to stifle protostellar fragmentation in the latter set of models, as when identical models were calculated without magnetic braking (Boss 2002), those cores fragmented into binary protostars. These models demonstrate the importance of including magnetic fields in studies of protostellar collapse and fragmentation, and suggest that even when magnetic fields are included, fragmentation into binary and multiple systems remains as a possible outcome of protostellar collapse.Comment: 20 pages, 8 figures. Astrophysical Journal, in pres

Algebraic and Geometric Models for Space Networking

In this paper we introduce some new algebraic and geometric perspectives on networked space communications. Our main contribution is a novel definition of a time-varying graph (TVG), defined in terms of a matrix with values in subsets of the real line P(R). We leverage semi-ring properties of P(R) to model multi-hop communication in a TVG using matrix multiplication and a truncated Kleene star. This leads to novel statistics on the communication capacity of TVGs called lifetime curves, which we generate for large samples of randomly chosen STARLINK satellites, whose connectivity is modeled over day-long simulations. Determining when a large subsample of STARLINK is temporally strongly connected is further analyzed using novel metrics introduced here that are inspired by topological data analysis (TDA). To better model networking scenarios between the Earth and Mars, we introduce various semi-rings capable of modeling propagation delay as well as protocols common to Delay Tolerant Networking (DTN), such as store-and-forward. Finally, we illustrate the applicability of zigzag persistence for featurizing different space networks and demonstrate the efficacy of K-Nearest Neighbors (KNN) classification for distinguishing Earth-Mars and Earth-Moon satellite systems using time-varying topology alone.Comment: 43 pages, 18 figures, comments welcom