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• 291. [Article] Freeway Control Via Ramp Metering: Development of a Basic Building Block for an On-Ramp, Discrete, Stochastic, Mesoscopic, Simulation Model within a Contextual Systems Approach

  One of the most effective measures of congestion control on freeways has been ramp metering, where vehicle entry to the freeway is regulated by traffic signals (meters). Meters are run with calibrated ...

  Citation × Citation Citation Abstract Copy Title: Freeway Control Via Ramp Metering: Development of a Basic Building Block for an On-Ramp, Discrete, Stochastic, Mesoscopic, Simulation Model within a Contextual Systems Approach Author: Alkadri, Mohamed Yaser Year: 1991 One of the most effective measures of congestion control on freeways has been ramp metering, where vehicle entry to the freeway is regulated by traffic signals (meters). Meters are run with calibrated influx rates to prevent highway saturation. However, recent observations of some metering sites in San Diego, CA indicate that metering, during peak hour demand, is helping freeway flow while sometimes creating considerable traffic back-ups on local streets, transferring congestion problems from the freeway to intersections. Metering problems stem largely from the difficulty of designing an integrated, dynamic metering scheme that responds not only to changing freeway conditions but also to fluctuating demand throughout the ramp network; a scheme whose objective is to maintain adequate freeway throughput as well as minimize disproportionate ramp delays and queue overspills onto surface streets. Simulation modeling is a versatile, convenient, relatively inexpensive and safe systems analysis tool for evaluating alternative strategies to achieve the above objective. The objective of this research was to establish a basic building block for a discrete system simulation model, ONRAMP, based on a stochastic, mesoscopic, queueing approach. ONRAMP is for modeling entrance ramp geometry, vehicular generation, platooning and arrivals, queueing activities, meters and metering rates. The architecture of ONRAMP's molecular unit is designed in a fashion so that it can be, with some model calibration, duplicated for a number of ramps and, if necessary, integrated into some other larger freeway network models. SLAM.II simulation language is used for computer implementation. ONRAMP has been developed and partly validated using data from eight ramps at Interstate-B in San Diego. From a systems perspective, simulation will be short-sided and problem analysis is incomplete unless the other non-technical metering problems are explored and considered. These problems include the impacts of signalizing entrance ramps on the vitality of adjacent intersections, land use and development, "fair" geographic distribution of meters and metering rates throughout the freeway corridor, public acceptance and enforcement, and the role and influence of organizations in charge of decision making in this regard. Therefore, an outline of a contextual systems approach for problem analysis is suggested. Benefits and problems of freeway control via ramp metering, both operational short-term and strategic long-term, are discussed in two dimensions: global (freeway) and local (intersection). The results of a pilot study which includes interviews with field experts and law enforcement officials and a small motorist survey are presented. Title: Freeway Control Via Ramp Metering: Development of a Basic Building Block for an On-Ramp, Discrete, Stochastic, Mesoscopic, Simulation Model within a Contextual Systems Approach Author: Alkadri, Mohamed Yaser Year: 1991 One of the most effective measures of congestion control on freeways has been ramp metering, where vehicle entry to the freeway is regulated by traffic signals (meters). Meters are run with calibrated influx rates to prevent highway saturation. However, recent observations of some metering sites in San Diego, CA indicate that metering, during peak hour demand, is helping freeway flow while sometimes creating considerable traffic back-ups on local streets, transferring congestion problems from the freeway to intersections. Metering problems stem largely from the difficulty of designing an integrated, dynamic metering scheme that responds not only to changing freeway conditions but also to fluctuating demand throughout the ramp network; a scheme whose objective is to maintain adequate freeway throughput as well as minimize disproportionate ramp delays and queue overspills onto surface streets. Simulation modeling is a versatile, convenient, relatively inexpensive and safe systems analysis tool for evaluating alternative strategies to achieve the above objective. The objective of this research was to establish a basic building block for a discrete system simulation model, ONRAMP, based on a stochastic, mesoscopic, queueing approach. ONRAMP is for modeling entrance ramp geometry, vehicular generation, platooning and arrivals, queueing activities, meters and metering rates. The architecture of ONRAMP's molecular unit is designed in a fashion so that it can be, with some model calibration, duplicated for a number of ramps and, if necessary, integrated into some other larger freeway network models. SLAM.II simulation language is used for computer implementation. ONRAMP has been developed and partly validated using data from eight ramps at Interstate-B in San Diego. From a systems perspective, simulation will be short-sided and problem analysis is incomplete unless the other non-technical metering problems are explored and considered. These problems include the impacts of signalizing entrance ramps on the vitality of adjacent intersections, land use and development, "fair" geographic distribution of meters and metering rates throughout the freeway corridor, public acceptance and enforcement, and the role and influence of organizations in charge of decision making in this regard. Therefore, an outline of a contextual systems approach for problem analysis is suggested. Benefits and problems of freeway control via ramp metering, both operational short-term and strategic long-term, are discussed in two dimensions: global (freeway) and local (intersection). The results of a pilot study which includes interviews with field experts and law enforcement officials and a small motorist survey are presented. Close

• 292. [Article] Developmental Mechanisms that Support Genome Stability and Embryonic Survival in Stress-tolerant Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i>

  In order to complete their life cycles, vertebrates require oxygen and water. However, environments are not always forgiving when it comes to constantly providing these basic needs for vertebrate life. ...

  Citation × Citation Citation Abstract Copy Title: Developmental Mechanisms that Support Genome Stability and Embryonic Survival in Stress-tolerant Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i> Author: Wagner, Josiah Tad Year: 2015 In order to complete their life cycles, vertebrates require oxygen and water. However, environments are not always forgiving when it comes to constantly providing these basic needs for vertebrate life. The annual killifish Austrofundulus limnaeus is possibly the most well described extremophile vertebrate and its embryos have been shown to tolerate extremes in oxygen, salinity, and water availability. This phenotype is likely a result of the annual killifish life history, which includes periods of temporary habitat desiccation and oxygen deprivation, and requires the production of stress-tolerant embryos that depress metabolism in a state of suspended animation, known as diapause. Over the past several decades, the basic morphology and physiology of annual killifish development has become better characterized. However, there are still basic cellular processes that remain to be described in annual killifish such as A. limnaeus. Specifically, changes in DNA structure, expression, and copy number are known to have profound impacts on the phenotype and survival of an organism. Little is known as to how A. limnaeus maintains genome integrity during cell stress, nor how the A. limnaeus nuclear and mitochondrial genomes may have evolved under the unpredictable conditions in which A. limnaeus thrive. Early annual killifish embryonic development is also characterized by a complete dispersion and subsequent reaggregation of embryonic blastomeres prior to formation of the embryonic axis. This unusual period of early development may provide a functional adaptation that allows annual killifish embryos to survive these extreme conditions. The overall goals of this project were to (1) characterize the ability of A. limnaeus to tolerate and repair DNA damage through enzymatic and developmental mechanisms, (2) to determine possible consequences of mitochondrial DNA sequence and copy number on the metabolism of A. limnaeus, and (3) to establish a draft genome of A. limnaeus for future comparative genome studies. The results of this project show that embryos of A. limnaeus have an impressive ability to survive and reverse high doses of DNA damage induced by ultraviolet-C (UV-C) radiation, especially when allowed to recover under photoreactivating light. Surprisingly, embryos that survived irradiation during blastomere dispersion phases were able to develop normally. Characterization of gene expression during embryonic development for genes important for axis formation and cellular differentiation suggests that A. limnaeus embryos may delay axis formation until several days after epiboly is complete, thus allowing time for cells that become damaged to be replaced by surrounding pluripotent cells. This outcome would represent first case of a developmental buffering stage in a vertebrate. A. limnaeus embryos are also unique in their mitochondrial response to anoxia. Whereas in other species the amount of mitochondrial DNA (mtDNA) copy number fluctuates following extremes in oxygen availability, A. limnaeus embryonic mtDNA remains stable. Additionally, characterization of the fully sequenced A. limnaeus mitochondrial genome reveals possible evolutionary adaptations that may have facilitated dormancy and anoxia tolerance when compared to other species within the Order Cyprinodontiformes. The final chapter of this project characterizes the draft genome of A. limnaeus and I provide evidence suggesting that epigenetic DNA methylation that may be involved in regulating diapause. Title: Developmental Mechanisms that Support Genome Stability and Embryonic Survival in Stress-tolerant Embryos of the Annual Killifish <i>Austrofundulus limnaeus</i> Author: Wagner, Josiah Tad Year: 2015 In order to complete their life cycles, vertebrates require oxygen and water. However, environments are not always forgiving when it comes to constantly providing these basic needs for vertebrate life. The annual killifish Austrofundulus limnaeus is possibly the most well described extremophile vertebrate and its embryos have been shown to tolerate extremes in oxygen, salinity, and water availability. This phenotype is likely a result of the annual killifish life history, which includes periods of temporary habitat desiccation and oxygen deprivation, and requires the production of stress-tolerant embryos that depress metabolism in a state of suspended animation, known as diapause. Over the past several decades, the basic morphology and physiology of annual killifish development has become better characterized. However, there are still basic cellular processes that remain to be described in annual killifish such as A. limnaeus. Specifically, changes in DNA structure, expression, and copy number are known to have profound impacts on the phenotype and survival of an organism. Little is known as to how A. limnaeus maintains genome integrity during cell stress, nor how the A. limnaeus nuclear and mitochondrial genomes may have evolved under the unpredictable conditions in which A. limnaeus thrive. Early annual killifish embryonic development is also characterized by a complete dispersion and subsequent reaggregation of embryonic blastomeres prior to formation of the embryonic axis. This unusual period of early development may provide a functional adaptation that allows annual killifish embryos to survive these extreme conditions. The overall goals of this project were to (1) characterize the ability of A. limnaeus to tolerate and repair DNA damage through enzymatic and developmental mechanisms, (2) to determine possible consequences of mitochondrial DNA sequence and copy number on the metabolism of A. limnaeus, and (3) to establish a draft genome of A. limnaeus for future comparative genome studies. The results of this project show that embryos of A. limnaeus have an impressive ability to survive and reverse high doses of DNA damage induced by ultraviolet-C (UV-C) radiation, especially when allowed to recover under photoreactivating light. Surprisingly, embryos that survived irradiation during blastomere dispersion phases were able to develop normally. Characterization of gene expression during embryonic development for genes important for axis formation and cellular differentiation suggests that A. limnaeus embryos may delay axis formation until several days after epiboly is complete, thus allowing time for cells that become damaged to be replaced by surrounding pluripotent cells. This outcome would represent first case of a developmental buffering stage in a vertebrate. A. limnaeus embryos are also unique in their mitochondrial response to anoxia. Whereas in other species the amount of mitochondrial DNA (mtDNA) copy number fluctuates following extremes in oxygen availability, A. limnaeus embryonic mtDNA remains stable. Additionally, characterization of the fully sequenced A. limnaeus mitochondrial genome reveals possible evolutionary adaptations that may have facilitated dormancy and anoxia tolerance when compared to other species within the Order Cyprinodontiformes. The final chapter of this project characterizes the draft genome of A. limnaeus and I provide evidence suggesting that epigenetic DNA methylation that may be involved in regulating diapause. Close

• 293. [Article] Occurrence and Concentrations of Caffeine in Seawater from the Oregon Coast and Potential Effects on the Dominant Mussel, Mytilus californianus

  Caffeine, a biologically active drug with many known molecular targets, is recognized as a contaminant of aquatic systems including marine systems. Although the concentrations of caffeine reported from ...

  Citation × Citation Citation Abstract Copy Title: Occurrence and Concentrations of Caffeine in Seawater from the Oregon Coast and Potential Effects on the Dominant Mussel, Mytilus californianus Author: Rodriguez del Rey, Zoe Year: 2010 Caffeine, a biologically active drug with many known molecular targets, is recognized as a contaminant of aquatic systems including marine systems. Although the concentrations of caffeine reported from aquatic systems are low (ng/L to μ/L), harmful ecological effects not detected by traditional toxicity tests could occur as a result of caffeine contamination. The goals of this thesis project were to: 1) quantify concentrations of caffeine occurring in the coastal ocean off of the Oregon Coast and to determine if higher levels were correlated with proximity to caffeine pollution sources; and 2) investigate the sub-lethal cellular toxicity of environmentally relevant concentrations of caffeine on Mytilus californianus, an intertidal mussel that is one of the dominant species of the Oregon Coast. Caffeine was analyzed at 14 locations in the coastal ocean off of the Oregon Coast. Sampling locations were stratified between populated areas identified as having sources of caffeine pollution and sites located in sparsely populated areas not in proximity to major caffeine pollution sources. Caffeine concentrations were also measured in the major water body discharging near sampling locations. Caffeine was detected in water from the coastal ocean off of the Oregon Coast at concentrations ranging from below the reporting limit to 44.7 ng/L. The occurrence and concentrations of caffeine in the coastal ocean did not correspond well with pollution threats from population density and point and non-point sources, but did correspond with a storm event occurrence. Caffeine concentrations in rivers and estuaries draining to the coast ranged from below the reporting limit to 152.2 ng/L. Hsp70, a molecular biomarker of cellular stress, was used to investigate the sub-lethal toxicity of environmentally relevant concentrations of caffeine to the mussel M. californianus. Hsp70 concentrations in the gill and mantle tissue of mussels exposed to 0.05, 0.2, and 0.5 μ/L of caffeine for 10, 20, and 30 days were compared to basal levels in control mussels. Hsp70 in the gill tissue of M. californianus had an initial attenuation of the stress protein followed by a significant albeit moderate up-regulation relative to controls in all but the 0.5 μ/L treatment. Hsp70 in the mantle tissue of mussels exposed to caffeine did not differ from control mussels. This Study confirms the presence of caffeine in Oregon's coastal ocean and provides laboratory evidence that environmentally relevant concentrations of caffeine can exert an effect on M. californianus gill tissue at the molecular-level. Title: Occurrence and Concentrations of Caffeine in Seawater from the Oregon Coast and Potential Effects on the Dominant Mussel, Mytilus californianus Author: Rodriguez del Rey, Zoe Year: 2010 Caffeine, a biologically active drug with many known molecular targets, is recognized as a contaminant of aquatic systems including marine systems. Although the concentrations of caffeine reported from aquatic systems are low (ng/L to μ/L), harmful ecological effects not detected by traditional toxicity tests could occur as a result of caffeine contamination. The goals of this thesis project were to: 1) quantify concentrations of caffeine occurring in the coastal ocean off of the Oregon Coast and to determine if higher levels were correlated with proximity to caffeine pollution sources; and 2) investigate the sub-lethal cellular toxicity of environmentally relevant concentrations of caffeine on Mytilus californianus, an intertidal mussel that is one of the dominant species of the Oregon Coast. Caffeine was analyzed at 14 locations in the coastal ocean off of the Oregon Coast. Sampling locations were stratified between populated areas identified as having sources of caffeine pollution and sites located in sparsely populated areas not in proximity to major caffeine pollution sources. Caffeine concentrations were also measured in the major water body discharging near sampling locations. Caffeine was detected in water from the coastal ocean off of the Oregon Coast at concentrations ranging from below the reporting limit to 44.7 ng/L. The occurrence and concentrations of caffeine in the coastal ocean did not correspond well with pollution threats from population density and point and non-point sources, but did correspond with a storm event occurrence. Caffeine concentrations in rivers and estuaries draining to the coast ranged from below the reporting limit to 152.2 ng/L. Hsp70, a molecular biomarker of cellular stress, was used to investigate the sub-lethal toxicity of environmentally relevant concentrations of caffeine to the mussel M. californianus. Hsp70 concentrations in the gill and mantle tissue of mussels exposed to 0.05, 0.2, and 0.5 μ/L of caffeine for 10, 20, and 30 days were compared to basal levels in control mussels. Hsp70 in the gill tissue of M. californianus had an initial attenuation of the stress protein followed by a significant albeit moderate up-regulation relative to controls in all but the 0.5 μ/L treatment. Hsp70 in the mantle tissue of mussels exposed to caffeine did not differ from control mussels. This Study confirms the presence of caffeine in Oregon's coastal ocean and provides laboratory evidence that environmentally relevant concentrations of caffeine can exert an effect on M. californianus gill tissue at the molecular-level. Close

• 294. [Article] Who Owns This Body?: Enslaved Women's Claim on Themselves

  During the antebellum period of U.S. slavery (1830-1861), many people claimed ownership of the enslaved woman's body, both legally and figuratively. The assumption that they were merely property, however, ...

  Citation × Citation Citation Abstract Copy Title: Who Owns This Body?: Enslaved Women's Claim on Themselves Author: Sandeen, Loucynda Elayna Year: 2013 During the antebellum period of U.S. slavery (1830-1861), many people claimed ownership of the enslaved woman's body, both legally and figuratively. The assumption that they were merely property, however, belies the unstable, shifting truths about bodily ownership. This thesis inquires into the gendered specifics and ambiguities of the law, the body, and women under slavery. By examining the particular bodily regulation and exploitation of enslaved women, especially around their reproductive labor, I suggest that new operations of oppression and also of resistance come into focus. The legal structure recognized enslaved women in the interest of owners, and this limitation was defining, meaning that justice flowed in one direction. If married white women were "civilly dead," as famously evoked by the Declaration of Sentiments (1848) then enslaved women were civilly non-existent. The law controlled, but did not protect slaves, and a number of opponents to slavery denounced this contradictory scenario during the antebellum era (and before). Literally, enslaved women were claimed by their masters, purchased and sold as chattel. Physically, they were claimed by those men (both white and black) who sought to have power over them. Symbolically, they were claimed by anti-slavers and pro-slavers alike when it suited their purposes, often in the domains of news and literature, for the sake of advancing their ideas, a rich record of which fills court cases, newsprint, and propaganda touching the slavery issue before the civil war. Due to the numerous ways that enslaved women's bodies have been claimed, owned, or circulated in markets, it may have been considered implicit to many that others owned their bodies. I believe that this is an oversimplified historical supposition that needs to be re-theorized. Indeed, enslaved women lived in a time when they were often led to believe that their bodies were not truly their own, and yet, many of them resisted their particular forms of oppression by claiming ownership of their bodies and those of their children; sometimes using rather extreme methods to keep from contributing to their oppression. In other words, slave owners' monopoly of the legal, economic, and logistical meanings of ownership of slaves had to be constantly reaffirmed and negotiated. This thesis asks: who owned the enslaved woman's body? I seek to emphasize that enslaved women were valid claimants of themselves as can seen in primary sources that today have only been given limited expression in the historiography. Title: Who Owns This Body?: Enslaved Women's Claim on Themselves Author: Sandeen, Loucynda Elayna Year: 2013 During the antebellum period of U.S. slavery (1830-1861), many people claimed ownership of the enslaved woman's body, both legally and figuratively. The assumption that they were merely property, however, belies the unstable, shifting truths about bodily ownership. This thesis inquires into the gendered specifics and ambiguities of the law, the body, and women under slavery. By examining the particular bodily regulation and exploitation of enslaved women, especially around their reproductive labor, I suggest that new operations of oppression and also of resistance come into focus. The legal structure recognized enslaved women in the interest of owners, and this limitation was defining, meaning that justice flowed in one direction. If married white women were "civilly dead," as famously evoked by the Declaration of Sentiments (1848) then enslaved women were civilly non-existent. The law controlled, but did not protect slaves, and a number of opponents to slavery denounced this contradictory scenario during the antebellum era (and before). Literally, enslaved women were claimed by their masters, purchased and sold as chattel. Physically, they were claimed by those men (both white and black) who sought to have power over them. Symbolically, they were claimed by anti-slavers and pro-slavers alike when it suited their purposes, often in the domains of news and literature, for the sake of advancing their ideas, a rich record of which fills court cases, newsprint, and propaganda touching the slavery issue before the civil war. Due to the numerous ways that enslaved women's bodies have been claimed, owned, or circulated in markets, it may have been considered implicit to many that others owned their bodies. I believe that this is an oversimplified historical supposition that needs to be re-theorized. Indeed, enslaved women lived in a time when they were often led to believe that their bodies were not truly their own, and yet, many of them resisted their particular forms of oppression by claiming ownership of their bodies and those of their children; sometimes using rather extreme methods to keep from contributing to their oppression. In other words, slave owners' monopoly of the legal, economic, and logistical meanings of ownership of slaves had to be constantly reaffirmed and negotiated. This thesis asks: who owned the enslaved woman's body? I seek to emphasize that enslaved women were valid claimants of themselves as can seen in primary sources that today have only been given limited expression in the historiography. Close

• 295. [Article] The Intellectual Grounding of the San Francisco Committee of Vigilance of 1851

  Vigilantism has a long history in the United States stretching back to the Regulator movement in South Carolina in 1767. These extralegal movements are distinguished from spontaneous and ephemeral mob ...

  Citation × Citation Citation Abstract Copy Title: The Intellectual Grounding of the San Francisco Committee of Vigilance of 1851 Author: Walker, Jon Jeffrey Year: 1993 Vigilantism has a long history in the United States stretching back to the Regulator movement in South Carolina in 1767. These extralegal movements are distinguished from spontaneous and ephemeral mob activity by their regular organization and limited life-span. The San Francisco Committee of Vigilance of 1856 was the largest vigilante movement in American history. After a summer of vigilantism that included four hangings, the committee turned to politics and formed the People’s Party which dominated San Francisco's city government for the next decade. The 1856 committee is generally considered the great exemplar of American vigilantism and has received considerable attention from scholars. San Francisco’s 1856 vigilance committee regarded itself as a reorganization of that city's 1851 Committee of Vigilance. Like its more illustrious offspring, the 1851 committee hanged four men and banished many others. The vigilantes of 1851 did not, however, form a political party. Because of this some scholars have considered the work of the 1851 committee to be incomplete and have deemed it less worthy of attention than the committee of 1856. But in attempting to understand the intellectual grounding of San Francisco's vigilantes, this view is incorrect. The vigilantes in 1856 felt they were carrying on the work of the 1851 committee. Thus, to comprehend the events of 1856 it is necessary to understand the inspiration for the 1851 vigilance committee. The key to vigilantism in San Francisco lies in 1851. An understanding of the spirit which animates vigilantism is valuable because of what it reveals about American concepts of self-government. Vigilantes conceive of their their authority as springing from the same source as does that of the government: the people. San Francisco provides an extraordinary case for the study of notions about popular sovereignty in antebellum America. In order to make sense of what happened in San Francisco in 1851 this thesis first analyzes the political thought and philosophy that had developed in America to that time. It also examines the changing social ethos that came to emphasize equality. The two vigilance committees of San Francisco were a consummation of the political and social developments of antebellum America. I have relied on the extensive secondary literature for my interpretation. San Francisco in 1851 was in the midst of a singular episode in American history: the gold rush. The promise of riches made California the reification of the ideals of equality and opportunity that matured during the antebellum era. For the exploration of California and San Francisco I have used secondary sources and some primary sources, especially the Alta California, one of San Francisco’s newspapers. This reliance on the Alta was in part due to its availability. The attitudes toward vigilantism expressed by the í‘œL후르 were similar to other California newspapers. All of them supported the vigilantes in 1851. The episode of vigilantism in 1851 was a formative experience for the city of San Francisco. It served as an example of popular action and helped to define the limits of such action for the city's residents. The relationship between popular action and government was illuminated in San Francisco. Because of the way in which the people were endowed with power, they could create government and later defy that same government without destroying their creation. Title: The Intellectual Grounding of the San Francisco Committee of Vigilance of 1851 Author: Walker, Jon Jeffrey Year: 1993 Vigilantism has a long history in the United States stretching back to the Regulator movement in South Carolina in 1767. These extralegal movements are distinguished from spontaneous and ephemeral mob activity by their regular organization and limited life-span. The San Francisco Committee of Vigilance of 1856 was the largest vigilante movement in American history. After a summer of vigilantism that included four hangings, the committee turned to politics and formed the People’s Party which dominated San Francisco's city government for the next decade. The 1856 committee is generally considered the great exemplar of American vigilantism and has received considerable attention from scholars. San Francisco’s 1856 vigilance committee regarded itself as a reorganization of that city's 1851 Committee of Vigilance. Like its more illustrious offspring, the 1851 committee hanged four men and banished many others. The vigilantes of 1851 did not, however, form a political party. Because of this some scholars have considered the work of the 1851 committee to be incomplete and have deemed it less worthy of attention than the committee of 1856. But in attempting to understand the intellectual grounding of San Francisco's vigilantes, this view is incorrect. The vigilantes in 1856 felt they were carrying on the work of the 1851 committee. Thus, to comprehend the events of 1856 it is necessary to understand the inspiration for the 1851 vigilance committee. The key to vigilantism in San Francisco lies in 1851. An understanding of the spirit which animates vigilantism is valuable because of what it reveals about American concepts of self-government. Vigilantes conceive of their their authority as springing from the same source as does that of the government: the people. San Francisco provides an extraordinary case for the study of notions about popular sovereignty in antebellum America. In order to make sense of what happened in San Francisco in 1851 this thesis first analyzes the political thought and philosophy that had developed in America to that time. It also examines the changing social ethos that came to emphasize equality. The two vigilance committees of San Francisco were a consummation of the political and social developments of antebellum America. I have relied on the extensive secondary literature for my interpretation. San Francisco in 1851 was in the midst of a singular episode in American history: the gold rush. The promise of riches made California the reification of the ideals of equality and opportunity that matured during the antebellum era. For the exploration of California and San Francisco I have used secondary sources and some primary sources, especially the Alta California, one of San Francisco’s newspapers. This reliance on the Alta was in part due to its availability. The attitudes toward vigilantism expressed by the í‘œL후르 were similar to other California newspapers. All of them supported the vigilantes in 1851. The episode of vigilantism in 1851 was a formative experience for the city of San Francisco. It served as an example of popular action and helped to define the limits of such action for the city's residents. The relationship between popular action and government was illuminated in San Francisco. Because of the way in which the people were endowed with power, they could create government and later defy that same government without destroying their creation. Close

• 296. [Article] A study of the arguments for and against the Factory Act of 1833 used by members of Parliament in the House of Commons

  During the eighteenth century England underwent vast changes in her methods of production. As a consequence the factory posed a new experience for the workers. Although conditions and hours of work were ...

  Citation × Citation Citation Abstract Copy Title: A study of the arguments for and against the Factory Act of 1833 used by members of Parliament in the House of Commons Author: Grundfossen, Peter D. Year: 1965 During the eighteenth century England underwent vast changes in her methods of production. As a consequence the factory posed a new experience for the workers. Although conditions and hours of work were better in textile factories than in most contemporary occupations, worker discontent was great because of the stricter regimen which the factory imposed. Conditions for children, generally the same as for the adults were no worse than they had always been. Although none of the early factory legislation was enforced, the Factory Act of 1833 and those that fol1owed are differentiated from previous efforts by their organized support, among which was that given by a group of Tory evangelicals. The evangelicals intended to limit hours to ten for all factory workers by restricting to that limit hours for persons up to eighteen years. The work of children and adults was so interrelated as to require them to work together. Legislation was introduced into commons in 1832 by Michael Sadler and in 1833 by Lord Ashley. Sadler's bill never got out of committee but the committee’s report served as a valuable source of propaganda. Ashley's bill was sent to a royal commission controlled by Benthamites who so altered the bill’s form as to cause Ashley to give it up. Acceptable to parliament in its new form, the bill clearly differentiated between child labor, which hours it limited to eight, and adult labor, which was left to protect itself. The Benthamite bill also required the manufacturers to provide education for their children; and inspectors were to attempt enforcement of regulations. Although parliamentary reform and an election had occurred in 1832, this revolution had no effect on the 1833 bill's passage. Factory legislation was the product of public demand and organized support rather than political upheaval. Furthermore, this was not a contest between Tories and Whigs, Establishment and evangelicals, or middle class and aristocracy. The simple motivation behind the bill was Christian humanitarianism. The debate arguments, themselves, fell into several categories and were repeated in volume and embellishment according to assumed value. The proponents of legislation emphasized the deleterious effect of the long hours; the inequities of the existing employment problem; and “the system” of competition and machinery which produced such conditions. The opponents threatened that family income would necessarily be reduced; that there would be massive unemployment due to collapse of the industry; and that such legislation would be contrary to natural laws of economics demanding free enterprise. Of course each side offered rebuttal to the other; conditions were really quite good; mortality rates were lower in the cities than elsewhere; the natural laws of economy would have to suffer rather than the children; there was no foreign competition, only British; and so forth. The Benthamite Factory Act was a disappointment to Ashley and his colleagues. They had failed in their effort to achieve a ten hour work-day. The effect was to spur them on to greater efforts. Ashley spent a successful lifetime in developing reform legislation. As with earlier legislation, this Act was poorly enforced: manufacturers and parents conspired to keep children at the mills; the education provisions were evaded or poorly employed. Of great value for the future, however, were the reports compiled by the parliamentary committee, the royal commission and the factory inspectors. These reports aided the reform effort later in the century. Title: A study of the arguments for and against the Factory Act of 1833 used by members of Parliament in the House of Commons Author: Grundfossen, Peter D. Year: 1965 During the eighteenth century England underwent vast changes in her methods of production. As a consequence the factory posed a new experience for the workers. Although conditions and hours of work were better in textile factories than in most contemporary occupations, worker discontent was great because of the stricter regimen which the factory imposed. Conditions for children, generally the same as for the adults were no worse than they had always been. Although none of the early factory legislation was enforced, the Factory Act of 1833 and those that fol1owed are differentiated from previous efforts by their organized support, among which was that given by a group of Tory evangelicals. The evangelicals intended to limit hours to ten for all factory workers by restricting to that limit hours for persons up to eighteen years. The work of children and adults was so interrelated as to require them to work together. Legislation was introduced into commons in 1832 by Michael Sadler and in 1833 by Lord Ashley. Sadler's bill never got out of committee but the committee’s report served as a valuable source of propaganda. Ashley's bill was sent to a royal commission controlled by Benthamites who so altered the bill’s form as to cause Ashley to give it up. Acceptable to parliament in its new form, the bill clearly differentiated between child labor, which hours it limited to eight, and adult labor, which was left to protect itself. The Benthamite bill also required the manufacturers to provide education for their children; and inspectors were to attempt enforcement of regulations. Although parliamentary reform and an election had occurred in 1832, this revolution had no effect on the 1833 bill's passage. Factory legislation was the product of public demand and organized support rather than political upheaval. Furthermore, this was not a contest between Tories and Whigs, Establishment and evangelicals, or middle class and aristocracy. The simple motivation behind the bill was Christian humanitarianism. The debate arguments, themselves, fell into several categories and were repeated in volume and embellishment according to assumed value. The proponents of legislation emphasized the deleterious effect of the long hours; the inequities of the existing employment problem; and “the system” of competition and machinery which produced such conditions. The opponents threatened that family income would necessarily be reduced; that there would be massive unemployment due to collapse of the industry; and that such legislation would be contrary to natural laws of economics demanding free enterprise. Of course each side offered rebuttal to the other; conditions were really quite good; mortality rates were lower in the cities than elsewhere; the natural laws of economy would have to suffer rather than the children; there was no foreign competition, only British; and so forth. The Benthamite Factory Act was a disappointment to Ashley and his colleagues. They had failed in their effort to achieve a ten hour work-day. The effect was to spur them on to greater efforts. Ashley spent a successful lifetime in developing reform legislation. As with earlier legislation, this Act was poorly enforced: manufacturers and parents conspired to keep children at the mills; the education provisions were evaded or poorly employed. Of great value for the future, however, were the reports compiled by the parliamentary committee, the royal commission and the factory inspectors. These reports aided the reform effort later in the century. Close

• 297. [Article] Changes in Oregon Batterer Intervention Program Characteristics in Relation to State Standards

  The social problem of intimate partner violence affects approximately one-half to two million individuals each year in the United States (Catalano, 2007; Tjaden & Thoennes, 2000). Commonly the criminal ...

  Citation × Citation Citation Abstract Copy Title: Changes in Oregon Batterer Intervention Program Characteristics in Relation to State Standards Author: Boal, Ashley Lynn Year: 2010 The social problem of intimate partner violence affects approximately one-half to two million individuals each year in the United States (Catalano, 2007; Tjaden & Thoennes, 2000). Commonly the criminal justice system mandates completion of a group-based intervention intended to prevent violent behavior (Dalton, 2007). These groups are typically referred to as a batterer intervention program (BIP). Despite the popularity of this intervention approach, research findings examining the efficacy of these programs remain inconsistent (Babcock, Green & Robie, 2004). Nonetheless, 45 U.S. states including the District of Columbia, have implemented standards that aim to proscribe and regulate elements of program functioning. To gain insight regarding the effects that standards implemented in the state of Oregon in 2006 have had on the functioning and characteristics of BIPs, this study examined survey data collected in 2001, 2004, and 2008 from a total of 76 BIPs functioning in Oregon. Several hypotheses were tested. First, it was hypothesized that program compliance with state standards would increase from 2001 to 2004 and from 2004 to 2008. Overall compliance did increase, though this change was not statistically significant. Consistent with this hypothesis, a statistically significant increase in one component of compliance, program length, was found between 2004 and 2008. Additionally, some components, such as collaboration with community partners, did not change in the expected direction. Second, the analyses tested whether programs that began functioning after the creation of the standards in 2006 would be more compliant with the standards than those operating prior to 2006. This was not the case; there was not a significant difference in the compliance ratios for programs that began functioning before and after 2006. Third, it was hypothesized that program characteristics of program size, location, and barriers to compliance would predict program compliance. This hypothesis was not supported; program size, location and barriers did not predict program compliance. These results indicate that some portions of the standards are being met by programs regardless of their program characteristics, while other components are not. Understanding which components of state standards programs are and are not in compliance with provides valuable insight into which components of standards may be difficult for programs to adhere. This information is important for understanding how programs may need assistance to comply with specific components and whether enforcement or formal monitoring of programs is necessary. Title: Changes in Oregon Batterer Intervention Program Characteristics in Relation to State Standards Author: Boal, Ashley Lynn Year: 2010 The social problem of intimate partner violence affects approximately one-half to two million individuals each year in the United States (Catalano, 2007; Tjaden & Thoennes, 2000). Commonly the criminal justice system mandates completion of a group-based intervention intended to prevent violent behavior (Dalton, 2007). These groups are typically referred to as a batterer intervention program (BIP). Despite the popularity of this intervention approach, research findings examining the efficacy of these programs remain inconsistent (Babcock, Green & Robie, 2004). Nonetheless, 45 U.S. states including the District of Columbia, have implemented standards that aim to proscribe and regulate elements of program functioning. To gain insight regarding the effects that standards implemented in the state of Oregon in 2006 have had on the functioning and characteristics of BIPs, this study examined survey data collected in 2001, 2004, and 2008 from a total of 76 BIPs functioning in Oregon. Several hypotheses were tested. First, it was hypothesized that program compliance with state standards would increase from 2001 to 2004 and from 2004 to 2008. Overall compliance did increase, though this change was not statistically significant. Consistent with this hypothesis, a statistically significant increase in one component of compliance, program length, was found between 2004 and 2008. Additionally, some components, such as collaboration with community partners, did not change in the expected direction. Second, the analyses tested whether programs that began functioning after the creation of the standards in 2006 would be more compliant with the standards than those operating prior to 2006. This was not the case; there was not a significant difference in the compliance ratios for programs that began functioning before and after 2006. Third, it was hypothesized that program characteristics of program size, location, and barriers to compliance would predict program compliance. This hypothesis was not supported; program size, location and barriers did not predict program compliance. These results indicate that some portions of the standards are being met by programs regardless of their program characteristics, while other components are not. Understanding which components of state standards programs are and are not in compliance with provides valuable insight into which components of standards may be difficult for programs to adhere. This information is important for understanding how programs may need assistance to comply with specific components and whether enforcement or formal monitoring of programs is necessary. Close

• 298. [Article] Effectiveness of Fuel Treatments for Mitigating Wildfire Risk and Sequestering Forest Carbon: A Case Study in the Lake Tahoe Basin

  Fuel-reduction treatments are used extensively to reduce wildfire risk and restore forest diversity and function. In the near future, increasing regulation of carbon (C) emissions may force forest managers ...

  Citation × Citation Citation Abstract Copy Title: Effectiveness of Fuel Treatments for Mitigating Wildfire Risk and Sequestering Forest Carbon: A Case Study in the Lake Tahoe Basin Author: Loudermilk, E. Louise, Stanton, Alison, Scheller, Robert M., Dilts, Thomas E., Weisberg, Peter J., Skinner, Carl, Yang, Jian Year: 2014 Fuel-reduction treatments are used extensively to reduce wildfire risk and restore forest diversity and function. In the near future, increasing regulation of carbon (C) emissions may force forest managers to balance the use of fuel treatments for reducing wildfire risk against an alternative goal of C sequestration. The objective of this study was to evaluate how long-term fuel treatments mitigate wildfires and affect forest C. For the Lake Tahoe Basin in the central Sierra Nevada, USA, fuel treatment efficiency was explored with a landscape-scale simulation model, LANDIS-II, using five fuel treatment scenarios and two (contemporary and potential future) fire regimes. Treatment scenarios included applying a combination of light (hand) and moderate (mechanical) forest thinning continuously through time and transitioning from these prescriptions to a more mid-seral thinning prescription, both on a 15 and 30 year rotation interval. In the last scenario, fuel treatments were isolated to around the lake shore (nearby urban settlement) to simulate a low investment alternative were future resources may be limited. Results indicated that the forest will remain a C sink regardless of treatment or fire regime simulated, due to the landscape legacy of historic logging. Achievement of a net C gain required decades with intensive treatment and depended on wildfire activity: Fuel treatments were more effective in a more active fire environment, where the interface between wildfires and treatment areas increased and caused net C gain earlier than as compared to our scenarios with less wildfire activity. Fuel treatments were most effective when continuously applied and strategically placed in high ignition areas. Treatment type and re-application interval were less influential at the landscape scale, but had notable effects on species dynamics within management units. Treatments created more diverse forest conditions by shifting dominance patterns to a more mixed conifer system, with a higher proportion of fire-tolerant species. We demonstrated that a small amount of wildfire on the landscape resulted in significant changes in the C pool, and that strategically placed fuel treatments substantially reduced wildfire risk, increased fire resiliency of the forest, and is beneficial for long-term C management. Implications for landscape management included consideration for prioritization of treatment areas and creating ideal re-entry schedules that meet logistic, safety, and conservation goals. In forests with a concentrated wildland urban interface, fuel treatments may be vital for ensuring human welfare and enhancing forest integrity in a fire-prone future. Title: Effectiveness of Fuel Treatments for Mitigating Wildfire Risk and Sequestering Forest Carbon: A Case Study in the Lake Tahoe Basin Author: Loudermilk, E. Louise, Stanton, Alison, Scheller, Robert M., Dilts, Thomas E., Weisberg, Peter J., Skinner, Carl, Yang, Jian Year: 2014 Fuel-reduction treatments are used extensively to reduce wildfire risk and restore forest diversity and function. In the near future, increasing regulation of carbon (C) emissions may force forest managers to balance the use of fuel treatments for reducing wildfire risk against an alternative goal of C sequestration. The objective of this study was to evaluate how long-term fuel treatments mitigate wildfires and affect forest C. For the Lake Tahoe Basin in the central Sierra Nevada, USA, fuel treatment efficiency was explored with a landscape-scale simulation model, LANDIS-II, using five fuel treatment scenarios and two (contemporary and potential future) fire regimes. Treatment scenarios included applying a combination of light (hand) and moderate (mechanical) forest thinning continuously through time and transitioning from these prescriptions to a more mid-seral thinning prescription, both on a 15 and 30 year rotation interval. In the last scenario, fuel treatments were isolated to around the lake shore (nearby urban settlement) to simulate a low investment alternative were future resources may be limited. Results indicated that the forest will remain a C sink regardless of treatment or fire regime simulated, due to the landscape legacy of historic logging. Achievement of a net C gain required decades with intensive treatment and depended on wildfire activity: Fuel treatments were more effective in a more active fire environment, where the interface between wildfires and treatment areas increased and caused net C gain earlier than as compared to our scenarios with less wildfire activity. Fuel treatments were most effective when continuously applied and strategically placed in high ignition areas. Treatment type and re-application interval were less influential at the landscape scale, but had notable effects on species dynamics within management units. Treatments created more diverse forest conditions by shifting dominance patterns to a more mixed conifer system, with a higher proportion of fire-tolerant species. We demonstrated that a small amount of wildfire on the landscape resulted in significant changes in the C pool, and that strategically placed fuel treatments substantially reduced wildfire risk, increased fire resiliency of the forest, and is beneficial for long-term C management. Implications for landscape management included consideration for prioritization of treatment areas and creating ideal re-entry schedules that meet logistic, safety, and conservation goals. In forests with a concentrated wildland urban interface, fuel treatments may be vital for ensuring human welfare and enhancing forest integrity in a fire-prone future. Close

• 299. [Article] The Effects of Global Change Upon United States Air Quality

  To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Global Change Upon United States Air Quality Author: Gonzalez-Abraham, Rodrigo, Chung, Serena H., Avise, Jeremy C., Lamb, Brian, Salathé, Eric P., Jr., Nolte, Christopher G., Loughlin, Dan, Guenther, Alex, Wiedinmyer, Christine, Duhl, Tiffany, Zhang, Yang, Streets, David G. Year: 2015 To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected global emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 parts per billion (ppb) across most of the continental US. The highest increase occurs in the South, Central and Midwest regions of the US due to increases in temperature, enhanced biogenic emissions and changes in land use. The model predicts an average increase of 1–6 ppb in DM8O due to projected increase in global emissions of ozone precursors. The effects of these factors are only partially offset by reductions in DM8O associated with decreasing US anthropogenic emissions. Increases in PM2.5 levels between 4 and 10 μg m−3 in the Northeast, Southeast, Midwest and South regions are mostly a result of increase in primary anthropogenic particulate matter (PM), enhanced biogenic emissions and land use changes. Changes in boundary conditions shift the composition but do not alter overall simulated PM2.5 mass concentrations. Title: The Effects of Global Change Upon United States Air Quality Author: Gonzalez-Abraham, Rodrigo, Chung, Serena H., Avise, Jeremy C., Lamb, Brian, Salathé, Eric P., Jr., Nolte, Christopher G., Loughlin, Dan, Guenther, Alex, Wiedinmyer, Christine, Duhl, Tiffany, Zhang, Yang, Streets, David G. Year: 2015 To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected global emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 parts per billion (ppb) across most of the continental US. The highest increase occurs in the South, Central and Midwest regions of the US due to increases in temperature, enhanced biogenic emissions and changes in land use. The model predicts an average increase of 1–6 ppb in DM8O due to projected increase in global emissions of ozone precursors. The effects of these factors are only partially offset by reductions in DM8O associated with decreasing US anthropogenic emissions. Increases in PM2.5 levels between 4 and 10 μg m−3 in the Northeast, Southeast, Midwest and South regions are mostly a result of increase in primary anthropogenic particulate matter (PM), enhanced biogenic emissions and land use changes. Changes in boundary conditions shift the composition but do not alter overall simulated PM2.5 mass concentrations. Close

• 300. [Article] Antisense transcription is pervasive but rarely conserved in enteric bacteria

  Noncoding RNAs, including antisense RNAs (asRNAs) that originate from the complementary strand of protein-coding genes, are involved in the regulation of gene expression in all domains of life. Recent ...

  Citation × Citation Citation Abstract Copy Title: Antisense transcription is pervasive but rarely conserved in enteric bacteria Author: Raghavan, Rahul, Sloan, D. B., Ochman, H. Year: 2012 Noncoding RNAs, including antisense RNAs (asRNAs) that originate from the complementary strand of protein-coding genes, are involved in the regulation of gene expression in all domains of life. Recent application of deep-sequencing technologies has revealed that the transcription of asRNAs occurs genome-wide in bacteria. Although the role of the vast majority of asRNAs remains unknown, it is often assumed that their presence implies important regulatory functions, similar to those of other noncoding RNAs. Alternatively, many antisense transcripts may be produced by chance transcription events from promoter-like sequences that result from the degenerate nature of bacterial transcription factor binding sites. To investigate the biological relevance of antisense transcripts, we compared genome-wide patterns of asRNA expression in closely related enteric bacteria, Escherichia coli and Salmonella enterica serovar Typhimurium, by performing strand-specific transcriptome sequencing. Although antisense transcripts are abundant in both species, less than 3% of asRNAs are expressed at high levels in both species, and only about 14% appear to be conserved among species. And unlike the promoters of protein-coding genes, asRNA promoters show no evidence of sequence conservation between, or even within, species. Our findings suggest that many or even most bacterial asRNAs are nonadaptive by-products of the cell's transcription machinery. IMPORTANCE Application of high-throughput methods has revealed the expression throughout bacterial genomes of transcripts encoded on the strand complementary to protein-coding genes. Because transcription is costly, it is usually assumed that these transcripts, termed antisense RNAs (asRNAs), serve some function; however, the role of most asRNAs is unclear, raising questions about their relevance in cellular processes. Because natural selection conserves functional elements, comparisons between related species provide a method for assessing functionality genome-wide. Applying such an approach, we assayed all transcripts in two closely related bacteria, Escherichia coli and Salmonella enterica serovar Typhimurium, and demonstrate that, although the levels of genome-wide antisense transcription are similarly high in both bacteria, only a small fraction of asRNAs are shared across species. Moreover, the promoters associated with asRNAs show no evidence of sequence conservation between, or even within, species. These findings indicate that despite the genome-wide transcription of asRNAs, many of these transcripts are likely nonfunctional. Title: Antisense transcription is pervasive but rarely conserved in enteric bacteria Author: Raghavan, Rahul, Sloan, D. B., Ochman, H. Year: 2012 Noncoding RNAs, including antisense RNAs (asRNAs) that originate from the complementary strand of protein-coding genes, are involved in the regulation of gene expression in all domains of life. Recent application of deep-sequencing technologies has revealed that the transcription of asRNAs occurs genome-wide in bacteria. Although the role of the vast majority of asRNAs remains unknown, it is often assumed that their presence implies important regulatory functions, similar to those of other noncoding RNAs. Alternatively, many antisense transcripts may be produced by chance transcription events from promoter-like sequences that result from the degenerate nature of bacterial transcription factor binding sites. To investigate the biological relevance of antisense transcripts, we compared genome-wide patterns of asRNA expression in closely related enteric bacteria, Escherichia coli and Salmonella enterica serovar Typhimurium, by performing strand-specific transcriptome sequencing. Although antisense transcripts are abundant in both species, less than 3% of asRNAs are expressed at high levels in both species, and only about 14% appear to be conserved among species. And unlike the promoters of protein-coding genes, asRNA promoters show no evidence of sequence conservation between, or even within, species. Our findings suggest that many or even most bacterial asRNAs are nonadaptive by-products of the cell's transcription machinery. IMPORTANCE Application of high-throughput methods has revealed the expression throughout bacterial genomes of transcripts encoded on the strand complementary to protein-coding genes. Because transcription is costly, it is usually assumed that these transcripts, termed antisense RNAs (asRNAs), serve some function; however, the role of most asRNAs is unclear, raising questions about their relevance in cellular processes. Because natural selection conserves functional elements, comparisons between related species provide a method for assessing functionality genome-wide. Applying such an approach, we assayed all transcripts in two closely related bacteria, Escherichia coli and Salmonella enterica serovar Typhimurium, and demonstrate that, although the levels of genome-wide antisense transcription are similarly high in both bacteria, only a small fraction of asRNAs are shared across species. Moreover, the promoters associated with asRNAs show no evidence of sequence conservation between, or even within, species. These findings indicate that despite the genome-wide transcription of asRNAs, many of these transcripts are likely nonfunctional. Close