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Accurate modeling and control of the gas exchange process in a modern turbocharged spark-ignited engine is critical for the control and analysis of different control strategies. This paper develops a simple physics-based, five-state engine model for a large four-stroke spark-ignited turbocharged engine fueled by natural gas that is used in variable speed applications. The control-oriented model is amenable for control algorithm development and includes the impacts of modulation to any combination of four actuators: throttle valve, bypass valve, fuel rate, and wastegate valve. The control problem requires tracking engine speed to provide propulsive power, differential pressure across the throttle valve to prevent compressor surge, air-to-fuel ratio to restrict engine emissions. Two validation strategies, open-loop and closed-loop, are used to validate the accuracy of both nonlinear and linear versions of the control-oriented model. The control models are able to capture the engine dynamics within 5%–10% error at most of the engine operating points. Finally, the relative gain array (RGA) is applied to the linearized engine model to understand the degree of interactions between plant inputs and outputs as a function of frequency for various operating points. Results of the RGA analysis show that the preferred input-output pairing changes depending on the linear plant model as well as frequency. Therefore, a coordinated controller is ideal to tackle the control problem in question.

This article argues that consciousness has a logically sound, explanatory framework, different from typical accounts that suffer from hidden mysticism. The article has three main parts. The first describes background principles concerning information processing in the brain, from which one can deduce a general, rational framework for explaining consciousness. The second part describes a specific theory that embodies those background principles, the Attention Schema Theory. In the past several years, a growing body of experimental evidence—behavioral evidence, brain imaging evidence, and computational modeling—has addressed aspects of the theory. The final part discusses the evolution of consciousness. By emphasizing the specific role of consciousness in cognition and behavior, the present approach leads to a proposed account of how consciousness may have evolved over millions of years, from fish to humans. The goal of this article is to present a comprehensive, overarching framework in which we can understand scientifically what consciousness is and what key adaptive roles it plays in brain function.

Surprisingly little is known about how the general public understands consciousness, yet information on common intuitions is crucial to discussions and theories of consciousness. We asked 202 members of the general public, “In your own words, what is consciousness?” and analyzed the frequencies with which different perspectives on consciousness were represented. Almost all people (89%) described consciousness as fundamentally receptive – possessing, knowing, perceiving, being aware, or experiencing. In contrast, the perspective that consciousness is agentic (actively making decisions, driving output, or controlling behavior) appeared in only 33% of responses. Consciousness as a social phenomenon was represented by 24% of people. Consciousness as being awake or alert was mentioned by 19%. Consciousness as mystical, transcending the physical world, was mentioned by only 10%. Consciousness in relation to memory was mentioned by 6%. Consciousness as an inner voice or inner being – the homunculus view – was represented by 5%. Finally, only three people (1.5%) mentioned a specific, scholarly theory about consciousness, suggesting that we successfully sampled the opinions of the general public rather than capturing an academic construct. We found little difference between men and women, young and old, or US and non-US participants, except for one possible generation shift. Young, non-US participants were more likely to associate consciousness with moral decision-making. These findings show a snapshot of the public understanding of consciousness – a network of associated concepts, represented at varying strengths, such that some are more likely to emerge when people are asked an open-ended question about it.

A logical explanation of consciousness has been known for decades. The brain must construct a specific set of information about conscious feeling (theory-of-mind information), causing people to believe, think, and claim to have consciousness. Theories that propose an actual, intangible feeling are non-explanatory. They add a magical red herring while leaving unexplained the objective phenomena: the believing, thinking, and claiming.

Why do we leak lubricant from the eyes to solicit comfort from others? Why do we bare our teeth and crinkle our faces to express non-aggression? The defensive mimic theory proposes that a broad range of human emotional expressions evolved originally as exaggerated, temporally extended mimics of the fast, defensive reflexes that normally protect the body surface. Defensive reflexes are so important to survival that they cannot be safely suppressed; yet they also broadcast information about an animal's internal state, information that can potentially be exploited by other animals. Once others can observe and exploit an animal's defensive reflexes, it may be advantageous to the animal to run interference by creating mimic defensive actions, thereby manipulating the behaviour of others. Through this interaction over millions of years, many human emotional expressions may have evolved. Here, human social signals including smiling, laughing and crying, are compared component-by-component with the known, well-studied features of primate defensive reflexes. It is suggested that the defensive mimic theory can adequately account for the physical form of not all, but a large range of, human emotional expression.

Consciousness is an unusual phenomenon to study scientifically. It is defined as a subjective, first-person phenomenon, and science is an objective, third-person endeavor. This misalignment between the means—science—and the end—explaining consciousness—gave rise to what has become a productive workaround: the search for ‘neural correlates of consciousness’ (NCCs). Science can sidestep trying to explain consciousness and instead focus on characterizing the kind(s) of neural activity that are reliably correlated with consciousness. However, while we have learned a lot about consciousness in the bargain, the NCC approach was not originally intended as the foundation for a true explanation of consciousness. Indeed, it was proposed precisely to sidestep the, arguably futile, attempt to find one. So how can an account, couched in terms of neural correlates, do the work that a theory is supposed to do: explain consciousness? The answer is that it cannot, and in fact most modern accounts of consciousness do not pretend to. Thus, here, we challenge whether or not any modern accounts of consciousness are in fact theories at all. Instead we argue that they are (competing) laws of consciousness. They describe what they cannot explain, just as Newton described gravity long before a true explanation was ever offered. We lay out our argument using a variety of modern accounts as examples and go on to argue that at least one modern account of consciousness, attention schema theory, goes beyond describing consciousness-related brain activity and qualifies as an explanatory theory.

The history of race, religion, and law in the United States is a story about who gets to be human and the relevance of human difference to political and material power. Each side in this argument marshaled a variety of scientific, theological, and intellectual arguments supporting its position. Consequently, we should not accept a simple binary in which religion either supports or obstructs processes of racialization in American history. Race and religion, rather, are co-constitutive. They have been defined and measured together since Europeans’ arrival in the western hemisphere. A focus on legal history is one way to track these developments. One of the primary contradictions in the relationship between religion and race in the U.S. legal system has been that, despite the promise of individual religious free exercise enshrined in the Constitution, dominant strands of American culture have long identified certain racial and religious groups as a threat to the security of the nation. The expansion of rights to minority groups has been, and remains, contested in American culture. “Race,” as Americans came to think about it, was encoded in laws, adjudicated in courts, enforced through government action, and conditioned everyday life. Ideas of race were closely related to religious and cultural assumptions about human nature and human origins. Much of the history of the United States, and the western hemisphere of which it is part, is linked to changing ideas about—even the emergence of—a terminology of “race,” “religion,” and related concepts.

BACKGROUND: Aspirin has been shown to lower the incidence and the mortality of vascular disease and cancer but its wider adoption appears to be seriously impeded by concerns about gastrointestinal (GI) bleeding. Unlike heart attacks, stroke and cancer, GI bleeding is an acute event, usually followed by complete recovery. We propose therefore that a more appropriate evaluation of the risk-benefit balance would be based on fatal adverse events, rather than on the incidence of bleeding. We therefore present a literature search and meta-analysis to ascertain fatal events attributable to low-dose aspirin. METHODS: In a systematic literature review we identified reports of randomised controlled trials of aspirin in which both total GI bleeding events and bleeds that led to death had been reported. Principal investigators of studies in which fatal events had not been adequately described were contacted via email and asked for further details. A meta-analyses was then performed to estimate the risk of fatal gastrointestinal bleeding attributable to low-dose aspirin. RESULTS: Eleven randomised trials were identified in the literature search. In these the relative risk (RR) of 'major' incident GI bleeding in subjects who had been randomised to low-dose aspirin was 1.55 (95% CI 1.33, 1.83), and the risk of a bleed attributable to aspirin being fatal was 0.45 (95% CI 0.25, 0.80). In all the subjects randomised to aspirin, compared with those randomised not to receive aspirin, there was no significant increase in the risk of a fatal bleed (RR 0.77; 95% CI 0.41, 1.43). CONCLUSIONS: The majority of the adverse events caused by aspirin are GI bleeds, and there appears to be no valid evidence that the overall frequency of fatal GI bleeds is increased by aspirin. The substantive risk for prophylactic aspirin is therefore cerebral haemorrhage which can be fatal or severely disabling, with an estimated risk of one death and one disabling stroke for every 1,000 people taking aspirin for ten years. These adverse effects of aspirin should be weighed against the reductions in vascular disease and cancer.

Geraci, Robert M. Apocalyptic AI: Visions of Heaven in Robotics, Artificial Intelligence, and Virtual Reality. New York: Oxford University Press, 2010. 248 + x pp.$27.95 (USD). Hardback. ISBN: 9780195393026 "To study intelligent robots is to study our culture," writes Robert M. Geraci in Apocalyptic AI: Visions of Heaven in Robotics, Artificial Intelligence, and Virtual Reality (7). Investigating the porous boundary between science fiction and popular science, Geraci seeks to show how the categories of Christian and Jewish apocalypticism have been used in techno-scientific contexts, particularly by those studying or writing about intelligent robots. The result is what Geraci terms "Apocalyptic AI," defined as "the presence of apocalyptic theology in popular science books on robotics and artificial intelligence" (1). Geraci argues that the category of Apocalyptic AI is "almost identical" to Christian and Jewish apocalyptic traditions (9). In his quest to understand the importance of Apocalyptic AI in American culture, Geraci engaged in ethnographic work at locales such as the Robotics Institute of Carnegie Mellon University, where the author interviewed roboticists, as well as the online game world Second Life, where the virtual inhabitants see their digital home as a "potential realm" for the realization of a "virtual future" (79). Apocalyptic AI, according to Geraci, is a "particularly American" phenomenon (21). Paul Boyer's work on the apocalypse is leveraged to show the ways in which scientists can "imagine the world in apocalyptic terms," particularly since World War II (21). Geraci also draws on Catherine Albanese's work to situate apocalyptic robots in a historical genealogy of other apocalyptic American traditions of the nineteenth century. The author traces this genealogy up to the early twenty-first century, where he reviews how Christian theologians and computer scientists are grappling with the moral, ethical, and legal implications of robotics research. Geraci is keen to make a methodological intervention in the study of religion and science. In one of the stronger passages of the book, Geraci chides the sociologists, anthropologists, and historians who study science without considering religion as part of the broader social context in which scientific research occurs. Religious studies, in Geraci's view, is also remiss for not engaging more productively with science and technology studies, which he sees as an ample source of data. …

Sarah Osborn's World: The Rise of Evangelical Christianity in Early America Catherine A. Brekus. New Haven, CT: Yale University Press, 2013.Catherine Brekus has accomplished something unique in Sarah Osborn's World: The Rise of Evangelical Christianity in Early America. In one sense, the book is about Sarah Osborn: her struggles, her triumphs, the way in which she narrates her own experiences, and finally the process through which her words were made relevant for future evangelicals. The story about Sarah is compelling. Yet the emphasis of the title should fall on the third word: Sarah Osborn's World. "Sarah" as Brekus calls her throughout the book-''the name she used when standing before God" (xiii)-is the lens through which Brekus approaches evangelicalism during the late colonial and early republic periods.One of the greatest strengths of the book-and the feature which will make this book widely assigned in the college classroom-is Brekus's ability to locate the many economic, scientific, religious, and political changes of the time in specific events from Sarah's life. To take one particularly powerful example, the death of Sarah's son Samuel renders the contortions of Calvinism in the modern world a page-turning experience. But Samuel's death is not simply an opportunity for a gripping story. Over the course of an entire chapter, Brekus takes the narrative of Samuel's death-his illness, his deathbed scene, his funeral and burial-and weaves into it commentary on a variety of components of eighteenth century life including apprenticeship practices, changing ideas on the salvation of children, the economics of child-rearing, shifting attitudes towards the physicality of hell among evangelicals, death and burial rituals, "proper" conversion experiences, and the evangelical regulation of mourning. Brekus concludes the chapter with a discussion on Sarah's understanding of the theological danger posed by loving one's child too much. As Brekus interprets Sarah's writings, "This was Sarah's sin: she had loved her son even more than God. Because she had worshipped Samuel as an idol, God had taken him away. His death was her fault" (166).Wrestling with Sarah's story promises to be one of the most fruitful parts of the book, particularly considering its potential uses in the university classroom. Brekus succeeds in making real the social disruptions posed by new understandings of both the human and divine. Brekus moves smoothly from the minutiae of Sarah's life to the larger economic, political, scientific, and religious changes of the time. …

Objective: The objective of this study was to compare the temporal resolution-related image quality of electrocardiography-gated images acquired with two multidetector computed tomography (CT) units with a moving heart phantom, at similar fixed heart rates, using half-scan and multisector acquisition modes. Methods: An adjustable moving heart phantom (Limbsandthings. Horfield, Bristol, UK) was used. Specific heart rates (47, 55, 64, 66, 69, and 73 beats per minute [bpm]) were chosen. On a General Electric CT unit (LightSpeed Plus; General Electric Medical Systems, Milwaukee, WI), retrospective half-scan and multisector mode protocols were performed. On a Siemens CT unit (Somatom Volume Zoom; Siemens, Forchheim, Germany), a retrospective half-scan mode was performed at 47. 55, and 64 bpm, and a two-sector mode was performed at 66, 69, and 73 bpm. Reformatted maximum intensity projection images were qualitatively compared and related to their temporal resolution. Results: Half-scan mode protocols provided similar good results with both CT units up to 55 bpm. The two-sector mode improved image quality compared with the half-scan mode. High temporal resolution with the multisector mode provided the best results. Conclusion: For coronary artery imaging, acquisition protocols that provide the highest temporal resolution are mandatory. The multisector mode is one technique that allows high temporal resolution but may be clinically inappropriate at heart rates below 65 bpm or when heart rate variation is observed during scan time.