Showing papers by "Michael D. Smith published in 2003"

Therapeutic applications of fenugreek.

Abstract: Fenugreek has a long history of medical uses in Ayurvedic and Chinese medicine, and has been used for numerous indications, including labor induction, aiding digestion, and as a general tonic to improve metabolism and health. Preliminary animal and human trials suggest possible hypoglycemic and antihyperlipidemic properties of oral fenugreek seed powder. (Altern Med Rev 2003;8(1):20-27)

Morphology and Composition of the Surface of Mars: Mars Odyssey THEMIS Results

Abstract: The Thermal Emission Imaging System (THEMIS) on Mars Odyssey has produced infrared to visible wavelength images of the martian surface that show lithologically distinct layers with variable thickness, implying temporal changes in the processes or environments during or after their formation. Kilometer-scale exposures of bedrock are observed; elsewhere airfall dust completely mantles the surface over thousands of square kilometers. Mars has compositional variations at 100-meter scales, for example, an exposure of olivine-rich basalt in the walls of Ganges Chasma. Thermally distinct ejecta facies occur around some craters with variations associated with crater age. Polar observations have identified temporal patches of water frost in the north polar cap. No thermal signatures associated with endogenic heat sources have been identified.

Discovery of Olivine in the Nili Fossae Region of Mars

Abstract: We have detected a 30,000-square-kilometer area rich in olivine in the Nili Fossae region of Mars. Nili Fossae has been interpreted as a complex of grabens and fractures related to the formation of the Isidis impact basin. We propose that post-impact faulting of this area has exposed subsurface layers rich in olivine. Linear mixture analysis of Thermal Emission Spectrometer spectra shows surface exposures of 30% olivine, where the composition of the olivine ranges from Fo30 to Fo70.

Method for preserving referential integrity within web sites

Abstract: The integrity of uniform resource locator (URL) references within web sites are maintained when changes occur in the locations where resources referenced by URLs are stored. A Referential Preservation Engine (RPE) maintains a database in which the location of web site documents and reference information are stored and updates various URL hyperlink references contained in the web pages on the site so that users can locate documents that have been moved to new storage locations. The RPE can also update links to external web sites by communicating with an RPE running on each external site. The RPE on the external site keeps track of the movement of linked documents on the sites and passes information pertaining to the new location of the linked documents to the local site, whereupon the links on the local web site pages are updated to reflect the new storage locations. The RPE also can track usage of a user's favorite sites and/or documents that are stored in an Internet browser and update the URL references for these favorites when the resources they are mapped to are moved (or renamed).

How Much Security Is Enough to Stop a Thief?: The Economics of Outsider Theft via Computer Systems and Networks.

Abstract: We address the question of how much security is required to protect a packaged system, installed in a large number of organizations, from thieves who would exploit a single vulnerability to attack multiple installations. While our work is motivated by the need to help organizations make decisions about how to defend themselves, we also show how they can better protect themselves by helping to protect each other.

Rapid Assessment of Drinking Water Quality: a Handbook for Implementation

Abstract: Water is a basic human right as recently re-clarified in General Comment 15 of the Committee on Economic, Social and Cultural Rights. The importance of water for health and development has been reflected in international policy initiatives since the International Decade for Water Supply and Sanitation Development (the 1980s). This was further emphasised by the Millennium Declaration Goal to halve the proportion of the World's population that lacks access to water supply and most recently the identification of water and sanitation as a highest priority issue by the Commission for Sustainable Development. Since the 1960s, WHO has periodically reported on the development of the access to safe drinking-water sources; this is now implemented as a joint programme of work with UNICEF through the WHO/UNICEF Joint Monitoring Programme (JMP) for Water Supply and Sanitation. In recent reviews and evaluations the need for JMP to progressively address new and emerging priorities has been highlighted. As part of the ongoing plan of work of JMP, a major initiative to more comprehensively take account of water quality issues has been initiated. This handbook has been developed as a resource to support the systematic evaluation of drinking-water quality status at country and local levels. It is hoped that it will be useful to those interested in describing and understanding drinking-water quality status in the context of JMP at national/state levels and on a project basis.

How Much Security Is Enough to Stop a Thief

Abstract: We address the question of how much security is required to protect a packaged system, installed in a large number of organizations, from thieves who would exploit a single vulnerability to attack multiple installations. While our work is motivated by the need to help organizations make decisions about how to defend themselves, we also show how they can better protect themselves by helping to protect each other.

Thermal Emission Imaging System (THEMIS) infrared observations of atmospheric dust and water ice cloud optical depth

Abstract: [1] The Mars Odyssey spacecraft entered into Martian orbit in October 2001 and after successful aerobraking, began mapping in February 2002. Thermal infrared images taken by the Thermal Emission Imaging System (THEMIS) on board the Odyssey spacecraft allow for the quantitative retrieval of atmospheric dust and water ice aerosol optical depth. Data collected so far cover late northern winter, spring, and summer (Ls = 330°–160°). During this period, THEMIS observed the decay of a regional dust storm, a number of local dust storms along the edge of the retreating north polar cap, and the growth of the low-latitude aphelion water ice cloud belt. Data from THEMIS complements the concurrent Mars Global Surveyor Thermal Emission Spectrometer (TES) data by sampling a later local time (∼1400 LT for TES versus ∼1600–1730 LT for THEMIS) and by observing at much higher spatial resolution. Comparison of water ice optical depth in the aphelion cloud belt from THEMIS and TES shows a significantly higher optical depth in the late afternoon (THEMIS) than in the early afternoon (TES).

Access for sale: a new class of worm

Abstract: The damage inflicted by viruses and worms has been limited by the risks that come with the more lucrative payloads. The problem facing authors of self-reproducing malware is that monetizing each intrusion requires the author to risk communication with the infected system. Malware authors looking to minimize risk and maximize loot have been better off carefully targeting trojan horses at a few systems at a time. However, this could change if malware authors could infect a large number of systems using a worm and sell access to infected systems to other black hats. We introduce a new type of worm that enables this division of labor, installing a back door on each infected system that opens only when presented a system-specific ticket generated by the worm's author. The risk to the worm's author is minimized because he need not communicate with the infected systems. This new class of attack could increase the incentives to write malware and create a market for such specialized skills. In addition to describing this new threat, we propose a number of approaches for defending against it.

Generational cache management of code traces in dynamic optimization systems

Abstract: A dynamic optimizer is a runtime software system that groups a program's instruction sequences into traces, optimizes those traces, stores the optimized traces in a software-based code cache, and then executes the optimized code in the code cache. To maximize performance, the vast majority of the program's execution should occur in the code cache and not in the different aspects of the dynamic optimization system. In the past, designers of dynamic optimizers have used the SPEC2000 benchmark suite to justify their use of simple code cache management schemes. In this paper, we show that the problem and importance of code cache management changes dramatically as we move from SPEC2000, with its relatively small number of dynamically generated code traces, to large interactive Windows applications. We also propose and evaluate a new cache management algorithm based on generational code caches that results in an average miss rate reduction of 18% over a unified cache, which translates into 19% fewer instructions spent in the dynamic optimizer. The algorithm categorizes code traces based on their expected lifetimes and group traces with similar lifetimes together in separate storage areas. Using this algorithm, short-lived code traces can easily be removed from a code cache without introducing fragmentation and without suffering the performance penalties associated with evicting long-lived code traces.

TES Limb-Geometry Observations of Aerosols

Abstract: The Thermal Emission Spectrometer (TES) on-board Mars Global Surveyor (MGS) has a pointing mirror that allows observations in the plane of the orbit anywhere from directly nadir to far above either the forward or aft limbs for details about the TES instrument). Nadir-geometry observations are defined as those where the field-of-view contains the surface of Mars (even if the actual observation is at a high emission angle far from true nadir). Limb-geometry observations are defined as those where the line-of-sight of the observations does not intersect the surface. At a number of points along the MGS orbit (typically every 10 deg. or 20 deg. of latitude) a limb sequence is taken, which includes a stack of overlapping TES spectra from just below the limb to more than 120 km above the limb. A typical limb sequence has approx. 20 individual spectra, and the projected size of a TES pixel at the limb is 13 km.

Chaparral monograph:a clinical decision support tool

Abstract: An evidence-based systematic review including scientific evidence, expert opinion, folkloric precedent, history, pharmacology, kinetics/ dynamics, interactions, adverse effects, toxicology, and dosing.

Interannual Comparison of Water Vapor in the North Polar Region of Mars

Abstract: In order to better understand the current climate of Mars, we seek to understand atmospheric water in the north polar region. Our approach is to examine the water transport and cycling issues within the north polar region and in/out of the region on seasonal and annual timescales. Viking Mars Atmospheric Water Detector (MAWD) data showed that water vapor increased as the northern summer season progressed and temperatures increased, and that vapor appeared to be transported southward . However, there has been uncertainty about the amount of water cycling in and out of the north polar region, as evidenced by residual polar cap visible brightness changes between one Martian year (Mariner 9 data) and a subsequent year (Viking data). These changes were originally thought to be interannual variations in the amount of frost sublimed based on global dust storm activity . However, Viking thermal and imaging data were re-examined and it was found that 14-35 pr m of water -ice appeared to be deposited on the cap later in the summer season, indicating that some water may be retained and redistributed within the polar cap region. This late summer deposition could be due to adsorption directly onto the cap surface or due to snowfall. We seek to understand what happens to the water on seasonal and interannual timescales. We address these issues by examining water vapor in the north polar region of Mars during the north spring and summer period from MGS TES data and by comparing these results to the Viking MAWD results.

Ecological risk assessment (ERA): how appropriate for developing countries?

Abstract: Most inhabitants of rural communities in developing countries depend on local ecosystems for their livelihoods. Any significant habitat alteration or modification could therefore have severe livelihood consequences in these rural communities. The demand for economic development in developing countries for national or regional economic growth cannot be overemphasised, but the benefits and risks from development projects have not been equitably distributed among the social strata. However, most development projects have adversely altered natural ecological systems, thereby affecting the natural productivity of these systems and local livelihoods. The destruction or undue modification of habitats with their rich and livelihood-sustaining biodiversity could be one reason for increasing the level of poverty in most rural communities in developing countries. The complexity and variability of ecological systems makes it even more difficult for ecological welfare assessments to be conducted, while the absence or inadequate baseline data has contributed to the low confidence of environmental assessments in these developing countries, particularly in Sub-Saharan Africa. Ecological risk assessment (ERA) provides a significant advance over traditional assessment approaches, by explicitly taking into consideration uncertainties associated with ecological systems. In this paper, the authors present an argument that if the ERA paradigm is correctly applied, it would be an appropriate tool for addressing the issues of intra-generational equity and ecological welfare and livelihoods in developing countries.

A New Class of Worm

Abstract: The damage inflicted by viruses and worms has been limited by the risks that come with the more lucrative payloads. The problem facing authors of self-reproducing malware is that monetizing each intrusion requires the author to risk communication with the infected system. Malware authors looking to minimize risk and maximize loot have been better off carefully targeting trojan horses at a few systems at a time. However, this could change if malware authors could infect a large number of systems using a worm and sell access to infected systems to other black hats. We introduce a new type of worm that enables this division of labor, installing a back door on each infected system that opens only when presented a system-specific ticket generated by the worm’s author. The risk to the worm’s author is minimized because he need not communicate with the infected systems. This new class of attack could increase the incentives to write malware and create a market for such specialized skills. In addition to describing this new threat, we propose a number of approaches for defending against it.