[Depressive realism: happiness or objectivity].

PubMed

Birinci, Fatih; Dirik, Gülay

2010-01-01

Realism is described as objective evaluations and judgments about the world; however, some research indicates that judgments made by "normal" people include a self-favored, positive bias in the perception of reality. Additionally, some studies report that compared to normal people, such cognitive distortions are less likely among depressive people. These findings gave rise to the depressive realism hypothesis. While results of several studies verify the notion that depressive people evaluate reality more objectively, other studies fail to support this hypothesis. Several causes for these inconsistent findings have been proposed, which can be characterized under 3 headings. One proposed explanation suggests that what is accepted as "realistic" in these studies is not quite objective and is in fact ambiguous. According to another perspective, the term "depressive" used in these studies is inconsistent with the criteria of scientific diagnostic methods. Another suggests that the research results can only be obtained under the specific experimental conditions. General negativity and limited processing are popular approaches used for explaining the depressive realism hypothesis. Nowadays, the debate over this hypothesis continues. The present review focuses on frequently cited research related to depressive realism and discusses the findings.

Testing local-realism and macro-realism under generalized dichotomic measurements

NASA Astrophysics Data System (ADS)

Das, Debarshi; Mal, Shiladitya; Home, Dipankar

2018-04-01

Generalized quantum measurements with two outcomes are fully characterized by two real parameters, dubbed as sharpness parameter and biasedness parameter and they can be linked with different aspects of the experimental setup. It is known that sharpness parameter characterizes precision of the measurements and decreasing sharpness parameter of the measurements reduces the possibility of probing quantum features like quantum mechanical (QM) violation of local-realism (LR) or macro-realism (MR). Here we investigate the effect of biasedness together with that of sharpness of measurements and find a trade-off between those two parameters in the context of probing QM violations of LR and MR. Interestingly, we also find that the above mentioned trade-off is more robust in the latter case.

Ontic structural realism and quantum field theory: Are there intrinsic properties at the most fundamental level of reality?

NASA Astrophysics Data System (ADS)

Berghofer, Philipp

2018-05-01

Ontic structural realism refers to the novel, exciting, and widely discussed basic idea that the structure of physical reality is genuinely relational. In its radical form, the doctrine claims that there are, in fact, no objects but only structure, i.e., relations. More moderate approaches state that objects have only relational but no intrinsic properties. In its most moderate and most tenable form, ontic structural realism assumes that at the most fundamental level of physical reality there are only relational properties. This means that the most fundamental objects only possess relational but no non-reducible intrinsic properties. The present paper will argue that our currently best physics refutes even this most moderate form of ontic structural realism. More precisely, I will claim that 1) according to quantum field theory, the most fundamental objects of matter are quantum fields and not particles, and show that 2) according to the Standard Model, quantum fields have intrinsic non-relational properties.

The methodological defense of realism scrutinized.

PubMed

Wray, K Brad

2015-12-01

I revisit an older defense of scientific realism, the methodological defense, a defense developed by both Popper and Feyerabend. The methodological defense of realism concerns the attitude of scientists, not philosophers of science. The methodological defense is as follows: a commitment to realism leads scientists to pursue the truth, which in turn is apt to put them in a better position to get at the truth. In contrast, anti-realists lack the tenacity required to develop a theory to its fullest. As a consequence, they are less likely to get at the truth. My aim is to show that the methodological defense is flawed. I argue that a commitment to realism does not always benefit science, and that there is reason to believe that a research community with both realists and anti-realists in it may be better suited to advancing science. A case study of the Copernican Revolution in astronomy supports this claim. Copyright © 2015 Elsevier Ltd. All rights reserved.

Stereochemistry of 1,2-elimination and proton-transfer reactions: toward a unified understanding.

PubMed

Mohrig, Jerry R

2013-07-16

Many mechanistic and stereochemical studies have focused on the breaking of the C-H bond through base-catalyzed elimination reactions. When we began our research, however, chemists knew almost nothing about the stereospecificity of addition-elimination reactions involving conjugated acyclic carbonyl compounds, even though the carbonyl group is a pivotal functional group in organic chemistry. Over the last 25 years, we have studied the addition-elimination reactions of β-substituted acyclic esters, thioesters, and ketones in order to reach a comprehensive understanding of how electronic effects influence their stereochemistry. This Account brings together our understanding of the stereochemistry of 1,2-elimination and proton-transfer reactions, describing how each study has built upon previous work and contributed to our understanding of this field. When we began, chemists thought that anti stereospecificity in base-catalyzed 1,2-elimination reactions occurred via concerted E2 mechanisms, which provide a smooth path for anti elimination. Unexpectedly, we discovered that some E1cBirrev reactions produce the same anti stereospecificity as E2 reactions even though they proceed through diffusionally equilibrated, "free" enolate-anion intermediates. This result calls into question the conventional wisdom that anti stereochemistry must result from a concerted mechanism. While carrying out our research, we developed insights ranging from the role of historical contingency in the evolution of hydratase-dehydratase enzymes to the influence of buffers on the stereochemistry of H/D exchange in D2O. Negative hyperconjugation is the most important concept for understanding our results. This idea provides a unifying view for the largely anti stereochemistry in E1cBirrev elimination reactions and a basis for understanding the stereoelectronic influence of electron-withdrawing β-substituents on proton-transfer reactions.

48 CFR 1515.404-475 - Cost realism.

Code of Federal Regulations, 2010 CFR

2010-10-01

... METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 1515.404-475 Cost realism. The EPA structured approach is not required when the contracting officer is evaluating cost realism in a competitive...

Nanoscale amphiphilic macromolecules with variable lipophilicity and stereochemistry modulate inhibition of oxidized low-density lipoprotein uptake.

PubMed

Poree, Dawanne E; Zablocki, Kyle; Faig, Allison; Moghe, Prabhas V; Uhrich, Kathryn E

2013-08-12

Amphiphilic macromolecules (AMs) based on carbohydrate domains functionalized with poly(ethylene glycol) can inhibit the uptake of oxidized low density lipoprotein (oxLDL) and counteract foam cell formation, a key characteristic of early atherogenesis. To investigate the influence of lipophilicity and stereochemistry on the AMs' physicochemical and biological properties, mucic acid-based AMs bearing four aliphatic chains (2a) and tartaric acid-based AMs bearing two (2b and 2l) and four aliphatic chains (2g and 2k) were synthesized and evaluated. Solution aggregation studies suggested that both the number of hydrophobic arms and the length of the hydrophobic domain impact AM micelle sizes, whereas stereochemistry impacts micelle stability. 2l, the meso analogue of 2b, elicited the highest reported oxLDL uptake inhibition values (89%), highlighting the crucial effect of stereochemistry on biological properties. This study suggests that stereochemistry plays a critical role in modulating oxLDL uptake and must be considered when designing biomaterials for potential cardiovascular therapies.

Violation of local realism with freedom of choice

PubMed Central

Scheidl, Thomas; Ursin, Rupert; Kofler, Johannes; Ramelow, Sven; Ma, Xiao-Song; Herbst, Thomas; Ratschbacher, Lothar; Fedrizzi, Alessandro; Langford, Nathan K.; Jennewein, Thomas; Zeilinger, Anton

2010-01-01

Bell’s theorem shows that local realistic theories place strong restrictions on observable correlations between different systems, giving rise to Bell’s inequality which can be violated in experiments using entangled quantum states. Bell’s theorem is based on the assumptions of realism, locality, and the freedom to choose between measurement settings. In experimental tests, “loopholes” arise which allow observed violations to still be explained by local realistic theories. Violating Bell’s inequality while simultaneously closing all such loopholes is one of the most significant still open challenges in fundamental physics today. In this paper, we present an experiment that violates Bell’s inequality while simultaneously closing the locality loophole and addressing the freedom-of-choice loophole, also closing the latter within a reasonable set of assumptions. We also explain that the locality and freedom-of-choice loopholes can be closed only within nondeterminism, i.e., in the context of stochastic local realism. PMID:21041665

Realism Assessment of Sonic Boom Simulators

NASA Technical Reports Server (NTRS)

Sullivan, Brenda M.; Davies, Patrica; Hodgdon, Kthleen K.; Salamone, Joseph A., III; Pilon, Anthony

2008-01-01

Developments in small supersonic aircraft design are predicted to result in low-intensity sonic booms. Booms generated by current aircraft are similar to those that led to the ban on commercial supersonic fli ght over the US, so are unsuitable for parametric studies of psychoac oustic response to low-intensity booms. Therefore, simulators have be en used to study the impact of predicted low-intensity sonic booms. H owever, simulators have been criticized because, when simulating conv entional-level booms, the sounds were observed to be unrealistic by p eople experienced in listening to sonic booms. Thus, two studies were conducted to measure the perceived realism of three sonic boom simul ators. Experienced listeners rated the realism of conventional sonic boom signatures when played in these simulators. The effects on percei ved realism of factors such as duration of post-boom noise, exclusion of very low frequency components, inclusion of ground reflections, a nd type of simulator were examined. Duration of post-boom noise was f ound to have a strong effect on perceived realism, while type of simu lator had a weak effect. It was determined that post-boom noise had t o be at least 1.5 seconds long for the sound to be rated very realist ic. Loudness level did not affect realism for the range of sounds pla yed in the tests (80-93 dB ASEL).

Child witnesses' metamemory realism.

PubMed

Allwood, Carl Martin; Granhag, Pär Anders; Jonsson, Anna-Carin

2006-12-01

This study investigated the degree of realism in the confidence judgments of 11 to 12-year-olds (41 girls and 40 boys) of their answers to questions relating to a short film clip showing a kidnapping event. Four different confidence scales were used: a numeric scale, a picture scale, a line scale and a written scale. The results demonstrated that the children showed a high level of overconfidence in their memories. However, no significant differences between the four confidence scales were found. Weak gender differences were found in that the girls were slightly, but significantly, better calibrated than the boys. In addition, although both boys and girls overestimated the total number of memory questions they had answered correctly, the boys gave higher estimates compared with the girls. In brief, the results indicate that, at least in the context investigated, 11-12 year-old children's confidence in and estimations of their own event memory show poor realism (overconfidence and overestimation). A comparison with previous research on adults indicates that 11 to 12-year-old children show noticeably poorer realism.

Earth Observing System Covariance Realism

NASA Technical Reports Server (NTRS)

Zaidi, Waqar H.; Hejduk, Matthew D.

2016-01-01

The purpose of covariance realism is to properly size a primary object's covariance in order to add validity to the calculation of the probability of collision. The covariance realism technique in this paper consists of three parts: collection/calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics. An empirical cumulative distribution function (ECDF) Goodness-of-Fit (GOF) method is employed to determine if a covariance is properly sized by comparing the empirical distribution of Mahalanobis distance calculations to the hypothesized parent 3-DoF chi-squared distribution. To realistically size a covariance for collision probability calculations, this study uses a state noise compensation algorithm that adds process noise to the definitive epoch covariance to account for uncertainty in the force model. Process noise is added until the GOF tests pass a group significance level threshold. The results of this study indicate that when outliers attributed to persistently high or extreme levels of solar activity are removed, the aforementioned covariance realism compensation method produces a tuned covariance with up to 80 to 90% of the covariance propagation timespan passing (against a 60% minimum passing threshold) the GOF tests-a quite satisfactory and useful result.

Ethical Realism: A Guide to Action?

ERIC Educational Resources Information Center

Matkin, Gary

2008-01-01

This article presents the author's response to Gary Miller's essay entitled "Ethical Realism and Continuing Education." In his essay, Dr. Miller has provided a valuable opportunity to reflect on the practice of continuing education (CE) leadership. Dr. Miller reviews six principles that are encapsulated in the concept of ethical realism, but are…

Perceived game realism: a test of three alternative models.

PubMed

Ribbens, Wannes

2013-01-01

Perceived realism is considered a key concept in explaining the mental processing of media messages and the societal impact of media. Despite its importance, little is known about its conceptualization and dimensional structure, especially with regard to digital games. The aim of this study was to test a six-factor model of perceived game realism comprised of simulational realism, freedom of choice, perceptual pervasiveness, social realism, authenticity, and character involvement and to assess it against an alternative single- and five-factor model. Data were collected from 380 male digital game users who judged the realism of the first-person shooter Half-Life 2 based upon their previous experience with the game. Confirmatory factor analysis was applied to investigate which model fits the data best. The results support the six-factor model over the single- and five-factor solutions. The study contributes to our knowledge of perceived game realism by further developing its conceptualization and measurement.

Critical Realism and Statistical Methods--A Response to Nash

ERIC Educational Resources Information Center

Scott, David

2007-01-01

This article offers a defence of critical realism in the face of objections Nash (2005) makes to it in a recent edition of this journal. It is argued that critical and scientific realisms are closely related and that both are opposed to statistical positivism. However, the suggestion is made that scientific realism retains (from statistical…

Hexuronic Acid Stereochemistry Determination in Chondroitin Sulfate Glycosaminoglycan Oligosaccharides by Electron Detachment Dissociation

NASA Astrophysics Data System (ADS)

Leach, Franklin E.; Ly, Mellisa; Laremore, Tatiana N.; Wolff, Jeremy J.; Perlow, Jacob; Linhardt, Robert J.; Amster, I. Jonathan

2012-09-01

Electron detachment dissociation (EDD) has previously provided stereo-specific product ions that allow for the assignment of the acidic C-5stereochemistry in heparan sulfate glycosaminoglycans (GAGs), but application of the same methodology to an epimer pair in the chondroitin sulfate glycoform class does not provide the same result. A series of experiments have been conducted in which glycosaminoglycan precursor ions are independently activated by electron detachment dissociation (EDD), electron induced dissociation (EID), and negative electron transfer dissociation (NETD) to assign the stereochemistry in chondroitin sulfate (CS) epimers and investigate the mechanisms for product ion formation during EDD in CS glycoforms. This approach allows for the assignment of electronic excitation products formed by EID and detachment products to radical pathways in NETD, both of which occur simultaneously during EDD. The uronic acid stereochemistry in electron detachment spectra produces intensity differences when assigned glycosidic and cross-ring cleavages are compared. The variations in the intensities of the doubly deprotonated 0,2X3 and Y3 ions have been shown to be indicative of CS-A/DS composition during the CID of binary mixtures. These ions can provide insight into the uronic acid composition of binary mixtures in EDD, but the relative abundances, although reproducible, are low compared with those in a CID spectrum acquired on an ion trap. The application of principal component analysis (PCA) presents a multivariate approach to determining the uronic acid stereochemistry spectra of these GAGs by taking advantage of the reproducible peak distributions produced by electron detachment.

Twenty-Five Centuries of Quantum Physics: From Pythagoras to Us, and from Subjectivism to Realism

NASA Astrophysics Data System (ADS)

Bunge, Mario

Three main theses are proposed. The first is that the idea of a quantum or minimal unit is not peculiar to quantum theory, since it already occurs in the classical theories of elasticity and electrolysis. Second, the peculiarities of the objects described by quantum theory are the following: their basic laws are probabilistic; some of their properties, such as position and energy, are blunt rather than sharp; two particles that were once together continue to be associated even after becoming spatially separated; and the vacuum has physical properties, so that it is a kind of matter. Third, the orthodox or Copenhagen interpretation of the theory is false, and may conveniently be replaced with a realist (though not classicist) interpretation. Heisenberg's inequality, Schrödinger's cat and Zeno's quantum paradox are discussed in the light of the two rival interpretations. It is also shown that the experiments that falsified Bell's inequality do not refute realism but the classicism inherent in hidden variables theories.

Realism, functions, and the a priori: Ernst Cassirer's philosophy of science.

PubMed

Heis, Jeremy

2014-12-01

This paper presents the main ideas of Cassirer's general philosophy of science, focusing on the two aspects of his thought that--in addition to being the most central ideas in his philosophy of science--have received the most attention from contemporary philosophers of science: his theory of the a priori aspects of physical theory, and his relation to scientific realism.

The evolution of offensive realism.

PubMed

Johnson, Dominic D P; Phil, D; Thayer, Bradley A

Offensive realism, a theory of international relations, holds that states are disposed to competition and conflict because they are self-interested, power maximizing, and fearful of other states. Moreover, it argues that states are obliged to behave this way because doing so favors survival in the international system. Debate continues as to whether modern states actually do, or should, behave in this way, but we are struck by a different question. In this article, we ask whether the three core assumptions about behavior in offensive realism-self-help, power maximization, and outgroup fear-have any basis in scientific knowledge about human behavioral evolution. We find that these precise traits are not only evolutionarily adaptive but also empirically common across the animal kingdom, especially in primate and human societies. Based on these findings, we hypothesize that states behave as offensive realists predict not just because of anarchy in the modern international system but also because of the legacy of our evolution. In short, offensive realism may really be describing the nature of the human species more than the nature of the international system. If our hypothesis is correct, then evolutionary theory offers the following: (1) a novel ultimate cause of offensive realist behavior; (2) an extension of offensive realism to any domain in which humans compete for power; and (3) an explanation for why individual leaders themselves, and not just states, seek power. However, a key insight from evolution is that the primacy of self-help, power maximization, and outgroup fear does not necessarily condemn individuals or groups to competition and conflict; rather, these traits can in themselves give rise to cooperation and alliances.

Response: Critical Realism--Response to Longhofer and Floersch

ERIC Educational Resources Information Center

Briar-Lawson, Katharine

2012-01-01

This article addresses key challenges posed by critical realism, proposed by Longhofer and Floersch, as a philosophical underpinning for a science of social work. As a response to Longhofer and Floersch, it is argued that critical realism may be instructive in debates about structural conditions that dictate more inclusive interventions and…

Host-Guest Assembly of a Molecular Reporter with Chiral Cyanohydrins for Assignment of Absolute Stereochemistry.

PubMed

Gholami, Hadi; Anyika, Mercy; Zhang, Jun; Vasileiou, Chrysoula; Borhan, Babak

2016-06-27

The absolute stereochemistry of cyanohydrins, derived from ketones and aldehydes, is obtained routinely, in a microscale and derivatization-free manner, upon their complexation with Zn-MAPOL, a zincated porphyrin host with a binding pocket comprised of a biphenol core. The host-guest complex leads to observable exciton-coupled circular dichroism (ECCD), the sign of which is easily correlated to the absolute stereochemistry of the bound cyanohydrin. A working model, based on the ECCD signal of cyanohydrins with known configuration, is proposed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The use of J-coupling as a sole criterion to assign the total absolute stereochemistry of new pyrrolidinone class synthetic analogs, derived from S-pyroglutamic acid

NASA Astrophysics Data System (ADS)

Kellici, Tahsin F.; Ntountaniotis, Dimitrios; Vanioti, Marianna; Golic Grdadolnik, Simona; Simcic, Mihael; Michas, Georgios; Moutevelis-Minakakis, Panagiota; Mavromoustakos, Thomas

2017-02-01

During the synthesis of new pyrrolidinone analogs possessing biological activity it is intriguing to assign their absolute stereochemistry as it is well known that drug potency is influenced by the stereochemistry. The combination of J-coupling information with theoretical results was used in order to establish their total stereochemistry when the chiral center of the starting material has known absolute stereochemistry. The J-coupling can be used as a sole criterion for novel synthetic analogs to identify the right stereochemistry. This approach is extremely useful especially in the case of analogs whose 2D NOESY spectra cannot provide this information. Few synthetic examples are given to prove the significance of this approach.

Cosmology and the Demise of Color Realism

NASA Astrophysics Data System (ADS)

Hockey, Thomas

2011-04-01

Scientific realism is a bulwark of modern metaphysics, especially entity realism. Scientists expect there to be real objects in nature that may be enumerated and measured using objective properties. (Rest mass is an example.) Is color one of these properties? The question, "What is the color of the Universe?" unexpectedly leads to the conclusion that it is not. Astronomers use the concept of color at their ontological peril.

Queer Genes: Realism, Sexuality and Science.

PubMed

Griffiths, David Andrew

2016-10-19

What are 'gay genes' and are they real? This article looks at key research into these hypothesized gay genes, made possible, in part, by the Human Genome Project. I argue that the complexity of both genetics and human sexuality demands a truly critical approach: one that takes into account feminist epistemologies of science and queer approaches to the body, while putting into conversation resources from agential realism and critical realism. This approach is able to maintain the agential complexity of genetic materiality, while also critically challenging the seemingly stable relationships between sex, gender and sexuality.

Realism and Pragmatism in a mixed methods study.

PubMed

Allmark, Peter; Machaczek, Katarzyna

2018-06-01

A discussion of how adopting a Realist rather than Pragmatist methodology affects the conduct of mixed methods research. Mixed methods approaches are now extensively employed in nursing and other healthcare research. At the same time, realist methodology is increasingly used as philosophical underpinning of research in these areas. However, the standard philosophical underpinning of mixed methods research is Pragmatism, which is generally considered incompatible or at least at odds with Realism. This paper argues that Realism can be used as the basis of mixed methods research and that doing so carries advantages over using Pragmatism. A mixed method study into patient handover reports is used to illustrate how Realism affected its design and how it would have differed had a Pragmatist approach been taken. Discussion Paper. Philosophers Index; Google Scholar. Those undertaking mixed methods research should consider the use of Realist methodology with the addition of some insights from Pragmatism to do with the start and end points of enquiry. Realism is a plausible alternative methodology for those undertaking mixed methods studies. © 2018 John Wiley & Sons Ltd.

Van't Hoff, Le Bel, and the Development of Stereochemistry: A Reassessment.

ERIC Educational Resources Information Center

Grossman, Robert B.

1989-01-01

Shows that two theories of stereochemistry were very different theories, grounded in different assumptions and were intended to explain different phenomena. Presents the original theories and later developments which caused a blending of the theories. (Author/MVL)

Can a virtual supermarket bring realism into the lab? Comparing shopping behavior using virtual and pictorial store representations to behavior in a physical store.

PubMed

van Herpen, Erica; van den Broek, Eva; van Trijp, Hans C M; Yu, Tian

2016-12-01

Immersive virtual reality techniques present new opportunities for research into consumer behavior. The current study examines whether the increased realism of a virtual store compared to pictorial (2D) stimuli elicits consumer behavior that is more in line with behavior in a physical store. We examine the number, variety, and type of products selected, amount of money spent, and responses to price promotions and shelf display, in three product categories (fruit & vegetables, milk, and biscuits). We find that virtual reality elicits behavior that is more similar to behavior in the physical store compared to the picture condition for the number of products selected (Milk: M store  = 1.19, M virtual  = 1.53, M pictures  = 2.58) and amount of money spent (Milk: M store  = 1.27, M virtual  = 1.53, M pictures  = 2.60 Euro), and for the selection of products from different areas of the shelf, both vertically (purchases from top shelves, milk and biscuits: P store  = 21.6%, P virtual  = 33.4%, P pictures  = 50.0%) and horizontally (purchase from left shelf, biscuits: P store  = 35.5%, P virtual  = 53.3%, P pictures  = 66.7%). This indicates that virtual reality can improve realism in responses to shelf allocation. Virtual reality was not able to diminish other differences between lab and physical store: participants bought more products and spent more money (for biscuits and fruit & vegetables), bought more national brands, and responded more strongly to price promotions in both virtual reality and pictorial representations than in the physical store. Implications for the use of virtual reality in studies of consumer food choice behavior as well as for future improvement of virtual reality techniques are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

DAG tales: the multiple faces of diacylglycerol--stereochemistry, metabolism, and signaling.

PubMed

Eichmann, Thomas Oliver; Lass, Achim

2015-10-01

The neutral lipids diacylglycerols (DAGs) are involved in a plethora of metabolic pathways. They function as components of cellular membranes, as building blocks for glycero(phospho)lipids, and as lipid second messengers. Considering their central role in multiple metabolic processes and signaling pathways, cellular DAG levels require a tight regulation to ensure a constant and controlled availability. Interestingly, DAG species are versatile in their chemical structure. Besides the different fatty acid species esterified to the glycerol backbone, DAGs can occur in three different stereo/regioisoforms, each with unique biological properties. Recent scientific advances have revealed that DAG metabolizing enzymes generate and distinguish different DAG isoforms, and that only one DAG isoform holds signaling properties. Herein, we review the current knowledge of DAG stereochemistry and their impact on cellular metabolism and signaling. Further, we describe intracellular DAG turnover and its stereochemistry in a 3-pool model to illustrate the spatial and stereochemical separation and hereby the diversity of cellular DAG metabolism.

Earth Observation System Flight Dynamics System Covariance Realism

NASA Technical Reports Server (NTRS)

Zaidi, Waqar H.; Tracewell, David

2016-01-01

This presentation applies a covariance realism technique to the National Aeronautics and Space Administration (NASA) Earth Observation System (EOS) Aqua and Aura spacecraft based on inferential statistics. The technique consists of three parts: collection calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics.

Queer Genes: Realism, Sexuality and Science

PubMed Central

Griffiths, David Andrew

2016-01-01

What are ‘gay genes’ and are they real? This article looks at key research into these hypothesized gay genes, made possible, in part, by the Human Genome Project. I argue that the complexity of both genetics and human sexuality demands a truly critical approach: one that takes into account feminist epistemologies of science and queer approaches to the body, while putting into conversation resources from agential realism and critical realism. This approach is able to maintain the agential complexity of genetic materiality, while also critically challenging the seemingly stable relationships between sex, gender and sexuality. PMID:28058037

A new paradigm for nursing: the potential of realism.

PubMed

Wainwright, S P

1997-12-01

Realism has been the dominant approach in the philosophy of science for the last 20 years. Realist philosophy has also been widely employed across a range of social sciences. Unfortunately, these powerful intellectual currents have not reached the shores of nursing which appears trapped in a time-warped debate about 'qualitative' (constructivist) and 'quantitative' (positivist) approaches. This paper argues that both positivism and constructionism are seriously flawed as philosophies of social and natural science. This is in marked contrast with realism which is a philosophy of both the natural and social sciences. I therefore propose that realism should be adopted as a radically different new paradigm for a unified biopsychosocial nursing.

Must Metaethical Realism Make a Semantic Claim?

PubMed

Kahane, Guy

2013-02-01

Mackie drew attention to the distinct semantic and metaphysical claims made by meta ethical realists, arguing that although our evaluative discourse is cognitive and objective, there are no objective evaluative facts. This distinction, however, also opens up a reverse possibility: that our evaluative discourse is antirealist, yet objective values do exist. I suggest that this seemingly far-fetched possibility merits serious attention; realism seems com mitted to its intelligibility, and, despite appearances, it isn't incoherent, ineffable, inherently implausible or impossible to defend. I argue that reflection on this possibility should lead us to revise our understanding of the debate between realists and antirealists. It is not only that the realist's semantic claim is insufficient for realism to be true, as Mackie argued; it's not even necessary. Robust metaethical realism is best understood as making a purely metaphysical claim. It is thus not enough for antirealists to show that our discourse is antirealist. They must directly attack the realist's metaphysical claim.

Must Metaethical Realism Make a Semantic Claim?

PubMed Central

Kahane, Guy

2012-01-01

Mackie drew attention to the distinct semantic and metaphysical claims made by meta ethical realists, arguing that although our evaluative discourse is cognitive and objective, there are no objective evaluative facts. This distinction, however, also opens up a reverse possibility: that our evaluative discourse is antirealist, yet objective values do exist. I suggest that this seemingly far-fetched possibility merits serious attention; realism seems com mitted to its intelligibility, and, despite appearances, it isn’t incoherent, ineffable, inherently implausible or impossible to defend. I argue that reflection on this possibility should lead us to revise our understanding of the debate between realists and antirealists. It is not only that the realist’s semantic claim is insufficient for realism to be true, as Mackie argued; it’s not even necessary. Robust metaethical realism is best understood as making a purely metaphysical claim. It is thus not enough for antirealists to show that our discourse is antirealist. They must directly attack the realist’s metaphysical claim. PMID:23525148

What is ontic structural realism?

NASA Astrophysics Data System (ADS)

Ainsworth, Peter Mark

In recent years a doctrine known as ontic structural realism (OSR) has achieved a degree of notoriety, but many people remain confused as to what exactly the doctrine amounts. In this paper three main variants of OSR are defined and discussed: (i) OSR1, which is the view that relations are ontologically primitive but objects and properties are not; (ii) OSR2, which is the view that objects and relations are ontologically primitive but properties are not; (iii) OSR3, which is the view that properties and relations are ontologically primitive but objects are not. Proponents of OSR claim that it is a "naturalistic" metaphysics, arguing that metaphysical views that take objects and/or properties as ontologically primitive are undermined by contemporary physics. In this paper it is argued that OSR1 and OSR2 are themselves undermined by contemporary physics. On the other hand, it is also argued that considerations about the objects of quantum mechanics and general relativity do seem to suggest that we should abandon some of our "common-sense" metaphysical intuitions, and that OSR3 is one of the metaphysical views that is compatible with what these theories seem to tell us about fundamental ontology.

The Interaction of Color Realism and Pictorial Recall Memory.

ERIC Educational Resources Information Center

Berry, Louis H.

This study investigated the interaction of variations in color realism on pictorial recall memory in order to better understand the effects of variations in color realism, and to draw comparisons between visual recall memory and visual recognition memory in terms of color information processing. Stimulus materials used were three sets of slides,…

The German VR Simulation Realism Scale--psychometric construction for virtual reality applications with virtual humans.

PubMed

Poeschl, Sandra; Doering, Nicola

2013-01-01

Virtual training applications with high levels of immersion or fidelity (for example for social phobia treatment) produce high levels of presence and therefore belong to the most successful Virtual Reality developments. Whereas display and interaction fidelity (as sub-dimensions of immersion) and their influence on presence are well researched, realism of the displayed simulation depends on the specific application and is therefore difficult to measure. We propose to measure simulation realism by using a self-report questionnaire. The German VR Simulation Realism Scale for VR training applications was developed based on a translation of scene realism items from the Witmer-Singer-Presence Questionnaire. Items for realism of virtual humans (for example for social phobia training applications) were supplemented. A sample of N = 151 students rated simulation realism of a Fear of Public Speaking application. Four factors were derived by item- and principle component analysis (Varimax rotation), representing Scene Realism, Audience Behavior, Audience Appearance and Sound Realism. The scale developed can be used as a starting point for future research and measurement of simulation realism for applications including virtual humans.

Reality check: the role of realism in stress reduction using media technology.

PubMed

de Kort, Y A W; Ijsselsteijn, W A

2006-04-01

There is a growing interest in the use of virtual and other mediated environments for therapeutic purposes. However, in the domain of restorative environments, virtual reality (VR) technology has hardly been used. Here the tendency has been to use mediated real environments, striving for maximum visual realism. This use of photographic material is mainly based on research in aesthetics judgments that has demonstrated the validity of this type of simulations as representations of real environments. Thus, restoration therapy is developing under the untested assumption that photorealistic images have the optimal level of realism, while in therapeutic applications 'experiential realism' seems to be the key rather than visual realism. The present paper discusses this contrast and briefly describes data of three studies aimed at exploring the importance and meaning of realism in the context of restorative environments.

Relativity, anomalies and objectivity loophole in recent tests of local realism

NASA Astrophysics Data System (ADS)

Bednorz, Adam

2017-11-01

Local realism is in conflict with special quantum Bell-type models. Recently, several experiments have demonstrated violation of local realism if we trust their setup assuming special relativity valid. In this paper we question the assumption of relativity, point out not commented anomalies and show that the experiments have not closed objectivity loophole because clonability of the result has not been demonstrated. We propose several improvements in further experimental tests of local realism make the violation more convincing.

Stereogame: An Interactive Computer Game That Engages Students in Reviewing Stereochemistry Concepts

ERIC Educational Resources Information Center

da Silva, Jose´ Nunes, Jr.; Lima, Mary Anne Sousa; Moreira, Joao Victor Xerez; Alexandre, Francisco Serra Oliveira; de Almeida, Diego Macedo; de Oliveira, Maria da Conceicao Ferreira; Leite, Antonio Jose´ Melo, Jr.

2017-01-01

This report provides information about an interactive computer game that allows undergraduate students to review individually stereochemistry topics in an engaging way by responding to 230 novel questions distributed at three difficulty levels. Responses from students and instructors who have played the game have been quite positive. Stereogame is…

Sesquiterpene lactone stereochemistry influences herbivore resistance and plant fitness in the field.

PubMed

Ahern, Jeffrey R; Whitney, Kenneth D

2014-03-01

Stereochemical variation is widely known to influence the bioactivity of compounds in the context of pharmacology and pesticide science, but our understanding of its importance in mediating plant-herbivore interactions is limited, particularly in field settings. Similarly, sesquiterpene lactones are a broadly distributed class of putative defensive compounds, but little is known about their activities in the field. Natural variation in sesquiterpene lactones of the common cocklebur, Xanthium strumarium (Asteraceae), was used in conjunction with a series of common garden experiments to examine relationships between stereochemical variation, herbivore damage and plant fitness. The stereochemistry of sesquiterpene lactone ring junctions helped to explain variation in plant herbivore resistance. Plants producing cis-fused sesquiterpene lactones experienced significantly higher damage than plants producing trans-fused sesquiterpene lactones. Experiments manipulating herbivore damage above and below ambient levels found that herbivore damage was negatively correlated with plant fitness. This pattern translated into significant fitness differences between chemotypes under ambient levels of herbivore attack, but not when attack was experimentally reduced via pesticide. To our knowledge, this work represents only the second study to examine sesquiterpene lactones as defensive compounds in the field, the first to document herbivore-mediated natural selection on sesquiterpene lactone variation and the first to investigate the ecological significance of the stereochemistry of the lactone ring junction. The results indicate that subtle differences in stereochemistry may be a major determinant of the protective role of secondary metabolites and thus of plant fitness. As stereochemical variation is widespread in many groups of secondary metabolites, these findings suggest the possibility of dynamic evolutionary histories within the Asteraceae and other plant families showing

Exorcising the Racism Phantasm: Racial Realism in Educational Research

ERIC Educational Resources Information Center

Blaisdell, Benjamin

2016-01-01

Based on a 3-year ethnographic project at a public elementary school in North Carolina, this article discusses how the concept of racial realism can be useful to researchers trying to live up to the goals of critical race studies in school-based research. Racial realism maintains that racism is a permanent aspect of U.S. society and schools. A…

Earth Observing System Covariance Realism Updates

NASA Technical Reports Server (NTRS)

Ojeda Romero, Juan A.; Miguel, Fred

2017-01-01

This presentation will be given at the International Earth Science Constellation Mission Operations Working Group meetings June 13-15, 2017 to discuss the Earth Observing System Covariance Realism updates.

Getting Real: Is Realism a Blind Spot in Research Methodology?

ERIC Educational Resources Information Center

McPhail, Graham; Lourie, Megan

2017-01-01

In this paper we outline a case for including realism as an approach for carrying out research in education. Realism is often missing or under-represented in methodology text books which tend to misrepresent positivism and over-claim the epistemic authority possible for interpretivism. While interpretivism is arguably the dominant research…

Brain networks, structural realism, and local approaches to the scientific realism debate.

PubMed

Yan, Karen; Hricko, Jonathon

2017-08-01

We examine recent work in cognitive neuroscience that investigates brain networks. Brain networks are characterized by the ways in which brain regions are functionally and anatomically connected to one another. Cognitive neuroscientists use various noninvasive techniques (e.g., fMRI) to investigate these networks. They represent them formally as graphs. And they use various graph theoretic techniques to analyze them further. We distinguish between knowledge of the graph theoretic structure of such networks (structural knowledge) and knowledge of what instantiates that structure (nonstructural knowledge). And we argue that this work provides structural knowledge of brain networks. We explore the significance of this conclusion for the scientific realism debate. We argue that our conclusion should not be understood as an instance of a global structural realist claim regarding the structure of the unobservable part of the world, but instead, as a local structural realist attitude towards brain networks in particular. And we argue that various local approaches to the realism debate, i.e., approaches that restrict realist commitments to particular theories and/or entities, are problematic insofar as they don't allow for the possibility of such a local structural realist attitude. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Wet-Lab Approach to Stereochemistry Using [superscript 31]P NMR Spectroscopy

ERIC Educational Resources Information Center

Fenton, Owen S.; Sculimbrene, Bianca R.

2011-01-01

Understanding stereochemistry is an important and difficult task for students to master in organic chemistry. In both introductory and advanced courses, students are encouraged to explore the spatial relationships between molecules, but this exploration is often limited either to the lecture hall or the confines of the library. As such, we sought…

Sesquiterpene lactone stereochemistry influences herbivore resistance and plant fitness in the field

PubMed Central

Ahern, Jeffrey R.; Whitney, Kenneth D.

2014-01-01

Background and Aims Stereochemical variation is widely known to influence the bioactivity of compounds in the context of pharmacology and pesticide science, but our understanding of its importance in mediating plant–herbivore interactions is limited, particularly in field settings. Similarly, sesquiterpene lactones are a broadly distributed class of putative defensive compounds, but little is known about their activities in the field. Methods Natural variation in sesquiterpene lactones of the common cocklebur, Xanthium strumarium (Asteraceae), was used in conjunction with a series of common garden experiments to examine relationships between stereochemical variation, herbivore damage and plant fitness. Key Results The stereochemistry of sesquiterpene lactone ring junctions helped to explain variation in plant herbivore resistance. Plants producing cis-fused sesquiterpene lactones experienced significantly higher damage than plants producing trans-fused sesquiterpene lactones. Experiments manipulating herbivore damage above and below ambient levels found that herbivore damage was negatively correlated with plant fitness. This pattern translated into significant fitness differences between chemotypes under ambient levels of herbivore attack, but not when attack was experimentally reduced via pesticide. Conclusions To our knowledge, this work represents only the second study to examine sesquiterpene lactones as defensive compounds in the field, the first to document herbivore-mediated natural selection on sesquiterpene lactone variation and the first to investigate the ecological significance of the stereochemistry of the lactone ring junction. The results indicate that subtle differences in stereochemistry may be a major determinant of the protective role of secondary metabolites and thus of plant fitness. As stereochemical variation is widespread in many groups of secondary metabolites, these findings suggest the possibility of dynamic evolutionary histories

An Essay for Educators: Epistemological Realism Really is Common Sense

NASA Astrophysics Data System (ADS)

Cobern, William W.; Loving, Cathleen C.

2008-04-01

“What is truth?” Pontius Pilot asked Jesus of Nazareth. For many educators today this question seems quaintly passé. Rejection of “truth” goes hand-in-hand with the rejection of epistemological realism. Educational thought over the last decade has instead been dominated by empiricist, anti-realist, instrumentalist epistemologies of two types: first by psychological constructivism and later by social constructivism. Social constructivism subsequently has been pressed to its logical conclusion in the form of relativistic multiculturalism. Proponents of both psychological constructivism and social constructivism value knowledge for its utility and eschew as irrelevant speculation any notion that knowledge is actually about reality. The arguments are largely grounded in the discourse of science and science education where science is “western” science; neither universal nor about what is really real. The authors defended the notion of science as universal in a previous article. The present purpose is to offer a commonsense argument in defense of critical realism as an epistemology and the epistemically distinguished position of science (rather than privileged) within a framework of epistemological pluralism. The paper begins with a brief cultural survey of events during the thirty-year period from 1960-1990 that brought many educators to break with epistemological realism and concludes with comments on the pedagogical importance of realism. Understanding the cultural milieu of the past forty years is critical to understanding why traditional philosophical attacks on social constructivist ideas have proved impotent defenders of scientific realism.

Using critical realism as a framework in pharmacy education and social pharmacy research.

PubMed

Oltmann, Carmen; Boughey, Chrissie

2012-01-01

This article challenges the idea that positivism is capable of representing the complexity of social pharmacy and pharmacy education. It is argued that critical realism provides a framework that allows researchers to look at the nature of reality and at mechanisms that produce, or have the tendency to produce, events and experiences of those events. Critical realism is a framework, not a method. It allows researchers to make observations about phenomena and explain the relationships and connections involved. The researcher has to look for mechanisms and structures that could explain why the phenomena, the connections, and the relationships exist (or do not) and then try to show that these mechanisms do exist. This article first contextualizes critical realism, then briefly describes it, and lastly exemplifies the use of critical realism in a discussion of a research project conducted in pharmacy education. Critical realism may be particularly useful in interdisciplinary research, for example, where practitioners and researchers are working together in a social pharmacy or pharmacy education setting. Critical realism requires the practitioners and the researchers to question and make known their assumptions about their own realities and to think of a complex problem or phenomenon in terms of a stratified reality, generative mechanisms, and tendencies. Critical realism may make research more rigorous and also allow researchers to conceive of a greater breadth of research designs for their work. Copyright © 2012 Elsevier Inc. All rights reserved.

Using NMR to Probe the Regio- and Stereochemistry of the Hydration of 1-Hexene

ERIC Educational Resources Information Center

Saba, Shahrokh; Clarke, Donald D.; Iwanoski, Christa; Lobasso, Thomas

2010-01-01

This undergraduate organic laboratory experiment complements previously described and popular experiments on hydration of 1-hexene where students experimentally establish the Markovnikov regioselectivity of alkene hydration. In this experiment, students explore not only the regiochemistry but also the stereochemistry of 1-hexene hydration and…

Julio Cortázar quotes on normal and abnormal movements: magical realism or reality?

PubMed

Merello, Marcelo

2006-08-01

Together with Mario Vargas Llosa and Gabriel García Márquez, Julio Cortázar was one of the most representative authors of the Latin American magical realism genre. Within his extensive body of work, many descriptions of characters suffering physical disabilities, as well as situations suggesting such medical conditions, can be extracted. In this review, two short stories by Cortázar are presented. In the first one, the main character could easily be a man suffering from corticobasal degeneration; in the second, an old woman with symptoms suggestive of progressive supranuclear palsy is clearly depicted. Despite the fact that one of the main ingredients in Cortázar's magical realism is fiction, cases described here fit real medical conditions quite well, making it hard to believe that they represent purely fantastic descriptions rather than the product of Cortázar's inquisitive observation and the description of real patients. (c) 2006 Movement Disorder Society

Ways of knowing: realism, non-realism, nominalism and a typology revisited with a counter perspective for nursing science.

PubMed

Garrett, Bernard M; Cutting, Roger L

2015-06-01

In this paper, we reconsider the context of Barbara Carper's alternative ways of knowing, a prominent discourse in modern nursing theory in North America. We explore this relative to the concepts of realism, non-realism and nominalism, and investigate the philosophical divisions behind the original typology, particularly in relationship to modern scientific enquiry. We examine forms of knowledge relative to realist and nominalist positions and make an argument ad absurdum against relativistic interpretations of knowledge using the example of Borge's Chinese Emporium of Benevolent Knowledge. We propose a contentious postpositivist practical classification for nursing knowledge that demonstrates and supports the idea that knowledge has both individual and subjective components. This classification supports the practical application of nursing knowledge within the paradigm of realist postpositivist science. © 2014 John Wiley & Sons Ltd.

Scientific Symbiosis Represents the Mutual Benefit of Iteratively Adopting the Perspective of Realism and Instrumentalism

ERIC Educational Resources Information Center

Cacioppo, John T.; Berntson, Gary G.; Semin, Gu R.

2005-01-01

This article presents comments on "Psychology Needs Realism not Instrumentalism" by B. Haig, "Ontological and Epistemic Claims of Realism and Instrumentalism" by Lau and "The Scientific Denial of the Real and the Dialectic of Scientism and Humanism" by Ramey and Chrysikou which were all comments on the original article "Realism, Instrumentalism,…

Evaluating the Effect of Display Realism on Natural Resource Decision Making

NASA Astrophysics Data System (ADS)

Chong, Steven S.

2018-05-01

Geographic information systems (GIS) facilitate location-based decision making. Despite the improved availability of GIS software to non-professionals, training in cartographic design has not followed suit. Prior research indicates that when presented with map choices, users are influenced by naïve realism, a preference for realistic displays cotaining irrelevant, extraneous details, leading to decreased task efficiency. This study investigated the role of naïve realism in decision making for natural resource management, a field that often employs geospatial tools. Data was collected through a GIS user ability test, a questionnaire and direct observation. Forty volunteer expert and non-expert resource managers evaluated the suitability of different sites for a land management scenario. Each participant was tested on two map display treatments containing different levels of realism - a simpler 2D display and a more complex 3D display - to compare task performance. Performance was measured by task accuracy and task completion time. User perceptions and preferences about the displays were also recorded. Display realism had an impact on performance and there were indications naïve realism was present. Users completed tasks significantly faster on the 2D display and many individuals misjudged which display they were most accurate or fastest with. The results are informative for designing information systems containing interactive maps, particularly for resource management applications. The results also suggest that the order displays were presented had a significant effect and may have implications for teaching users map-based tasks.

Pilot Task Profiles, Human Factors, And Image Realism

NASA Astrophysics Data System (ADS)

McCormick, Dennis

1982-06-01

Computer Image Generation (CIG) visual systems provide real time scenes for state-of-the-art flight training simulators. The visual system reauires a greater understanding of training tasks, human factors, and the concept of image realism to produce an effective and efficient training scene than is required by other types of visual systems. Image realism must be defined in terms of pilot visual information reauirements. Human factors analysis of training and perception is necessary to determine the pilot's information requirements. System analysis then determines how the CIG and display device can best provide essential information to the pilot. This analysis procedure ensures optimum training effectiveness and system performance.

Multivariate Analysis of Electron Detachment Dissociation and Infrared Multiphoton Dissociation Mass Spectra of Heparan Sulfate Tetrasaccharides Differing Only in Hexuronic acid Stereochemistry

NASA Astrophysics Data System (ADS)

Oh, Han Bin; Leach, Franklin E.; Arungundram, Sailaja; Al-Mafraji, Kanar; Venot, Andre; Boons, Geert-Jan; Amster, I. Jonathan

2011-03-01

The structural characterization of glycosaminoglycan (GAG) carbohydrates by mass spectrometry has been a long-standing analytical challenge due to the inherent heterogeneity of these biomolecules, specifically polydispersity, variability in sulfation, and hexuronic acid stereochemistry. Recent advances in tandem mass spectrometry methods employing threshold and electron-based ion activation have resulted in the ability to determine the location of the labile sulfate modification as well as assign the stereochemistry of hexuronic acid residues. To facilitate the analysis of complex electron detachment dissociation (EDD) spectra, principal component analysis (PCA) is employed to differentiate the hexuronic acid stereochemistry of four synthetic GAG epimers whose EDD spectra are nearly identical upon visual inspection. For comparison, PCA is also applied to infrared multiphoton dissociation spectra (IRMPD) of the examined epimers. To assess the applicability of multivariate methods in GAG mixture analysis, PCA is utilized to identify the relative content of two epimers in a binary mixture.

Do Props Matter in the Dramatic Play Center? The Effects of Prop Realism on Children's Play.

ERIC Educational Resources Information Center

Hogan, Claudia; Howe, Nina

2001-01-01

This study investigated the effects of prop realism on the play of 24 preschoolers. Observations of play sessions revealed that highly realistic props and low-realism props elicited equal amounts of group dramatic play. However, low- realism props generated greater diversity of play themes, more fantasy role enactments, and more nonintended use of…

Did Ptolemy make novel predictions? Launching Ptolemaic astronomy into the scientific realism debate.

PubMed

Carman, Christián; Díez, José

2015-08-01

The goal of this paper, both historical and philosophical, is to launch a new case into the scientific realism debate: geocentric astronomy. Scientific realism about unobservables claims that the non-observational content of our successful/justified empirical theories is true, or approximately true. The argument that is currently considered the best in favor of scientific realism is the No Miracles Argument: the predictive success of a theory that makes (novel) observational predictions while making use of non-observational content would be inexplicable unless such non-observational content approximately corresponds to the world "out there". Laudan's pessimistic meta-induction challenged this argument, and realists reacted by moving to a "selective" version of realism: the approximately true part of the theory is not its full non-observational content but only the part of it that is responsible for the novel, successful observational predictions. Selective scientific realism has been tested against some of the theories in Laudan's list, but the first member of this list, geocentric astronomy, has been traditionally ignored. Our goal here is to defend that Ptolemy's Geocentrism deserves attention and poses a prima facie strong case against selective realism, since it made several successful, novel predictions based on theoretical hypotheses that do not seem to be retained, not even approximately, by posterior theories. Here, though, we confine our work just to the detailed reconstruction of what we take to be the main novel, successful Ptolemaic predictions, leaving the full analysis and assessment of their significance for the realist thesis to future works. Copyright © 2015. Published by Elsevier Ltd.

Time Perception and Depressive Realism: Judgment Type, Psychophysical Functions and Bias

PubMed Central

Kornbrot, Diana E.; Msetfi, Rachel M.; Grimwood, Melvyn J.

2013-01-01

The effect of mild depression on time estimation and production was investigated. Participants made both magnitude estimation and magnitude production judgments for five time intervals (specified in seconds) from 3 sec to 65 sec. The parameters of the best fitting psychophysical function (power law exponent, intercept, and threshold) were determined individually for each participant in every condition. There were no significant effects of mood (high BDI, low BDI) or judgment (estimation, production) on the mean exponent, n = .98, 95% confidence interval (.96–1.04) or on the threshold. However, the intercept showed a ‘depressive realism’ effect, where high BDI participants had a smaller deviation from accuracy and a smaller difference between estimation and judgment than low BDI participants. Accuracy bias was assessed using three measures of accuracy: difference, defined as psychological time minus physical time, ratio, defined as psychological time divided by physical time, and a new logarithmic accuracy measure defined as ln (ratio). The ln (ratio) measure was shown to have approximately normal residuals when subjected to a mixed ANOVA with mood as a between groups explanatory factor and judgment and time category as repeated measures explanatory factors. The residuals of the other two accuracy measures flagrantly violated normality. The mixed ANOVAs of accuracy also showed a strong depressive realism effect, just like the intercepts of the psychophysical functions. There was also a strong negative correlation between estimation and production judgments. Taken together these findings support a clock model of time estimation, combined with additional cognitive mechanisms to account for the depressive realism effect. The findings also suggest strong methodological recommendations. PMID:23990960

Radical constructivism: Between realism and solipsism

NASA Astrophysics Data System (ADS)

Martínez-Delgado, Alberto

2002-11-01

This paper criticizes radical constructivism of the Glasersfeld type, pointing out some contradictions between the declared radical principles and their theoretical and practical development. These contradictions manifest themselves in a frequent oscillation between solipsism and realism, despite constructivist claims to be an anti-realist theory. The paper also points out the contradiction between the relativism of the radical constructivist principles and the constructivist exclusion of other epistemological or educational paradigms. It also disputes the originality and importance of the radical constructivist paradigm, suggesting the idea of an isomorphism between radical constructivist theory and contemplative realism. In addition, some pedagogical and scientific methodological aspects of the radical constructivist model are examined. Although radical constructivism claims to be a rational theory and advocates deductive thinking, it is argued that there is no logical deductive connection between the radical principles of constructivism and the radical constructivist ideas about scientific research and learning. The paper suggests the possibility of an ideological substratum in the construction and hegemonic success of subjective constructivism and, finally, briefly advances an alternative realist model to epistemological and educational radical constructivism.

Stereochemistry- and concentration-dependent effects of phosphatidylserine enrichment on platelet function.

PubMed

Meyer, Audrey F; Gruba, Sarah M; Kim, Donghyuk; Meyer, Ben M; Koseoglu, Secil; Dalluge, Joseph J; Haynes, Christy L

2017-08-01

Platelets are small (1-2μm in diameter), circulating anuclear cell fragments with important roles in hemostasis and thrombosis that provide an excellent platform for studying the role of membrane components in cellular communication. Platelets use several forms of communication including exocytosis of three distinct granule populations, formation of bioactive lipid mediators, and shape change (allowing for adhesion). This work explores the role of stereochemistry and concentration of exogenous phosphatidylserine (PS) on platelet exocytosis and adhesion. PS, most commonly found in the phosphatidyl-l-serine (l-PS) form, is exposed on the outer leaflet of the cell membrane after the platelet is activated. Knowledge about the impact of exogenous phosphatidylserine on cell-to-cell communication is limited (particularly concentration and stereochemistry effects). This study found that platelets incubated in l-PS or phosphatidyl-d-serine (d-PS) are enriched to the same extent with their respective incubated PS. All levels of l-PS enrichment also showed an increase in platelet cholesterol, but only the 50μM d-PS incubation showed an increase in cholesterol. The uptake of d-PS induced the secretion of granules and manufactured platelet activating factor (PAF) in otherwise unstimulated platelets. The uptake of l-PS had a greater impact on platelet stimulation by decreasing both the amount of δ-granule secretion and the amount of PAF that was manufactured. Copyright © 2017 Elsevier B.V. All rights reserved.

Asymptotically optimal data analysis for rejecting local realism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yanbao; Applied and Computational Mathematics Division, National Institute of Standards and Technology, Boulder, Colorado 80305; Glancy, Scott

2011-12-15

Reliable experimental demonstrations of violations of local realism are highly desirable for fundamental tests of quantum mechanics. One can quantify the violation witnessed by an experiment in terms of a statistical p value, which can be defined as the maximum probability according to local realism of a violation at least as high as that witnessed. Thus, high violation corresponds to small p value. We propose a prediction-based-ratio (PBR) analysis protocol whose p values are valid even if the prepared quantum state varies arbitrarily and local realistic models can depend on previous measurement settings and outcomes. It is therefore not subjectmore » to the memory loophole [J. Barrett et al., Phys. Rev. A 66, 042111 (2002)]. If the prepared state does not vary in time, the p values are asymptotically optimal. For comparison, we consider protocols derived from the number of standard deviations of violation of a Bell inequality and from martingale theory [R. Gill, e-print arXiv:quant-ph/0110137]. We find that the p values of the former can be too small and are therefore not statistically valid, while those derived from the latter are suboptimal. PBR p values do not require a predetermined Bell inequality and can be used to compare results from different tests of local realism independent of experimental details.« less

Adding computationally efficient realism to Monte Carlo turbulence simulation

NASA Technical Reports Server (NTRS)

Campbell, C. W.

1985-01-01

Frequently in aerospace vehicle flight simulation, random turbulence is generated using the assumption that the craft is small compared to the length scales of turbulence. The turbulence is presumed to vary only along the flight path of the vehicle but not across the vehicle span. The addition of the realism of three-dimensionality is a worthy goal, but any such attempt will not gain acceptance in the simulator community unless it is computationally efficient. A concept for adding three-dimensional realism with a minimum of computational complexity is presented. The concept involves the use of close rational approximations to irrational spectra and cross-spectra so that systems of stable, explicit difference equations can be used to generate the turbulence.

Beyond the realism debate: The metaphysics of 'racial' distinctions.

PubMed

Lemeire, Olivier

2016-10-01

The current metaphysical race debate is very much focused on the realism question whether races exist. In this paper I argue against the importance of this question. Philosophers, biologists and anthropologists expect that answering this question will tell them something substantive about the metaphysics of racial classifications, and will help them to decide whether it is justified to use racial categories in scientific research and public policy. I argue that there are two reasons why these expectations are not fulfilled. First of all, the realism question about race leads to a very broad philosophical debate about the semantics of general terms and the criteria for real kinds, rather than to a debate about the metaphysics of racial categories specifically. Secondly, there is a type of race realism that is so toothless that it is almost completely uninformative about the metaphysics of race. In response to these worries, I argue that the metaphysical race debate should rather be focused on the question in what way and to what extent 'racial' distinctions can ground the epistemic practices of various scientific disciplines. I spell out what I mean by this, and go on to demonstrate that trying to answer this question leads to a more fruitful metaphysical debate. Copyright © 2016 Elsevier Ltd. All rights reserved.

Absolute configuration of a chiral CHD group via neutron diffraction: confirmation of the absolute stereochemistry of the enzymatic formation of malic acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bau, R.; Brewer, I.; Chiang, M.Y.

Neutron diffraction has been used to monitor the absolute stereochemistry of an enzymatic reaction. (-)(2S)malic-3-d acid was prepared by the action of fumarase on fumaric acid in D/sub 2/O. After a large number of cations were screened, it was found that (+)(R)..cap alpha..-phenylethylamine forms the large crystals necessary for a neutron diffraction analysis. The subsequent structure determination showed that (+)(R)..cap alpha..-phenylethylammonium (-)(2S)malate-3-d has an absolute configuration of R at the CHD site. This result confirms the absolute stereochemistry of fumarate-to-malate transformation as catalyzed by the enzyme fumarase.

Critical Realism and Empirical Bioethics: A Methodological Exposition.

PubMed

McKeown, Alex

2017-09-01

This paper shows how critical realism can be used to integrate empirical data and philosophical analysis within 'empirical bioethics'. The term empirical bioethics, whilst appearing oxymoronic, simply refers to an interdisciplinary approach to the resolution of practical ethical issues within the biological and life sciences, integrating social scientific, empirical data with philosophical analysis. It seeks to achieve a balanced form of ethical deliberation that is both logically rigorous and sensitive to context, to generate normative conclusions that are practically applicable to the problem, challenge, or dilemma. Since it incorporates both philosophical and social scientific components, empirical bioethics is a field that is consistent with the use of critical realism as a research methodology. The integration of philosophical and social scientific approaches to ethics has been beset with difficulties, not least because of the irreducibly normative, rather than descriptive, nature of ethical analysis and the contested relation between fact and value. However, given that facts about states of affairs inform potential courses of action and their consequences, there is a need to overcome these difficulties and successfully integrate data with theory. Previous approaches have been formulated to overcome obstacles in combining philosophical and social scientific perspectives in bioethical analysis; however each has shortcomings. As a mature interdisciplinary approach critical realism is well suited to empirical bioethics, although it has hitherto not been widely used. Here I show how it can be applied to this kind of research and explain how it represents an improvement on previous approaches.

Energy-time entanglement, elements of reality, and local realism

NASA Astrophysics Data System (ADS)

Jogenfors, Jonathan; Larsson, Jan-Åke

2014-10-01

The Franson interferometer, proposed in 1989 (Franson 1989 Phys. Rev. Lett. 62 2205-08), beautifully shows the counter-intuitive nature of light. The quantum description predicts sinusoidal interference for specific outcomes of the experiment, and these predictions can be verified in experiment. In the spirit of Einstein, Podolsky, and Rosen it is possible to ask if the quantum-mechanical description (of this setup) can be considered complete. This question will be answered in detail in this paper, by delineating the quite complicated relation between energy-time entanglement experiments and Einstein-Podolsky-Rosen (EPR) elements of reality. The mentioned sinusoidal interference pattern is the same as that giving a violation in the usual Bell experiment. Even so, depending on the precise requirements made on the local realist model, this can imply (a) no violation, (b) smaller violation than usual, or (c) full violation of the appropriate statistical bound. Alternatives include (a) using only the measurement outcomes as EPR elements of reality, (b) using the emission time as EPR element of reality, (c) using path realism, or (d) using a modified setup. This paper discusses the nature of these alternatives and how to choose between them. The subtleties of this discussion needs to be taken into account when designing and setting up experiments intended to test local realism. Furthermore, these considerations are also important for quantum communication, for example in Bell-inequality-based quantum cryptography, especially when aiming for device independence. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘50 years of Bell’s theorem’.

Testing nonlocal realism with entangled coherent states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paternostro, Mauro; Jeong, Hyunseok

2010-03-15

We investigate the violation of nonlocal realism using entangled coherent states (ECSs) under nonlinear operations and homodyne measurements. We address recently proposed Leggett-type inequalities, including a class of optimized incompatibility inequalities proposed by Branciard et al. [Nature Phys. 4, 681 (2008)], and thoroughly assess the effects of detection inefficiency.

Constraining geostatistical models with hydrological data to improve prediction realism

NASA Astrophysics Data System (ADS)

Demyanov, V.; Rojas, T.; Christie, M.; Arnold, D.

2012-04-01

Geostatistical models reproduce spatial correlation based on the available on site data and more general concepts about the modelled patters, e.g. training images. One of the problem of modelling natural systems with geostatistics is in maintaining realism spatial features and so they agree with the physical processes in nature. Tuning the model parameters to the data may lead to geostatistical realisations with unrealistic spatial patterns, which would still honour the data. Such model would result in poor predictions, even though although fit the available data well. Conditioning the model to a wider range of relevant data provide a remedy that avoid producing unrealistic features in spatial models. For instance, there are vast amounts of information about the geometries of river channels that can be used in describing fluvial environment. Relations between the geometrical channel characteristics (width, depth, wave length, amplitude, etc.) are complex and non-parametric and are exhibit a great deal of uncertainty, which is important to propagate rigorously into the predictive model. These relations can be described within a Bayesian approach as multi-dimensional prior probability distributions. We propose a way to constrain multi-point statistics models with intelligent priors obtained from analysing a vast collection of contemporary river patterns based on previously published works. We applied machine learning techniques, namely neural networks and support vector machines, to extract multivariate non-parametric relations between geometrical characteristics of fluvial channels from the available data. An example demonstrates how ensuring geological realism helps to deliver more reliable prediction of a subsurface oil reservoir in a fluvial depositional environment.

Searching for realism, structure and agency in Actor Network Theory.

PubMed

Elder-Vass, Dave

2008-09-01

Superficially, Actor Network Theory (ANT) and critical realism (CR) are radically opposed research traditions. Written from a realist perspective, this paper asks whether there might be a basis for finding common ground between these two traditions. It looks in turn at the questions of realism, structure, and agency, analysing the differences between the two perspectives and seeking to identify what each might learn from the other. Overall, the paper argues that there is a great deal that realists can learn from actor network theory; yet ANT remains stunted by its lack of a depth ontology. It fails to recognize the significance of mechanisms, and of their dependence on emergence, and thus lacks both dimensions of the depth that is characteristic of critical realism's ontology. This prevents ANT from recognizing the role and powers of social structure; but on the other hand, realists would do well to heed ANT's call for us to trace the connections through which structures are constantly made and remade. A lack of ontological depth also underpins ANT's practice of treating human and non-human actors symmetrically, yet this remains a valuable provocation to sociologists who neglect non-human entities entirely.

Piloting Augmented Reality Technology to Enhance Realism in Clinical Simulation.

PubMed

Vaughn, Jacqueline; Lister, Michael; Shaw, Ryan J

2016-09-01

We describe a pilot study that incorporated an innovative hybrid simulation designed to increase the perception of realism in a high-fidelity simulation. Prelicensure students (N = 12) cared for a manikin in a simulation lab scenario wearing Google Glass, a wearable head device that projected video into the students' field of vision. Students reported that the simulation gave them confidence that they were developing skills and knowledge to perform necessary tasks in a clinical setting and that they met the learning objectives of the simulation. The video combined visual images and cues seen in a real patient and created a sense of realism the manikin alone could not provide.

Aesthetic Description and Realism in Art Education.

ERIC Educational Resources Information Center

Brown, Neil C. M.

1989-01-01

Looks at the usefulness of a stable realism for questions related to the description and understanding of art works. Explores two theories which may resolve the antagonism between representational meanings and their assertion as true properties of the work: (1) Wiggin's concept of authentic effect; and (2) Petit's theory of rectification and…

Buried chloride stereochemistry in the Protein Data Bank

PubMed Central

2014-01-01

Background Despite the chloride anion is involved in fundamental biological processes, its interactions with proteins are little known. In particular, we lack a systematic survey of its coordination spheres. Results The analysis of a non-redundant set (pairwise sequence identity?stereochemistry is closer to the expected geometry when the coordination number is 5, suggesting that this is the coordination number towards which the chlorides tend when they interact with proteins. Conclusions The results of these analyses are useful in interpreting, describing, and validating new protein crystal structures that contain chloride anions. PMID:25928393

Buried chloride stereochemistry in the Protein Data Bank.

PubMed

Carugo, Oliviero

2014-09-23

Despite the chloride anion is involved in fundamental biological processes, its interactions with proteins are little known. In particular, we lack a systematic survey of its coordination spheres. The analysis of a non-redundant set (pairwise sequence identity < 30%) of 1739 high resolution (<2 Å) crystal structures that contain at least one chloride anion shows that the first coordination spheres of the chlorides are essentially constituted by hydrogen bond donors. Amongst the side-chains positively charged, arginine interacts with chlorides much more frequently than lysine. Although the most common coordination number is 4, the coordination stereochemistry is closer to the expected geometry when the coordination number is 5, suggesting that this is the coordination number towards which the chlorides tend when they interact with proteins. The results of these analyses are useful in interpreting, describing, and validating new protein crystal structures that contain chloride anions.

Realism and Romance: The Study of Media Effects.

ERIC Educational Resources Information Center

Tuchman, Gaye

1993-01-01

Compares and contrasts two studies representing diametrical approaches (Romanticism versus Realism) toward the issue of agency and media effects: P. Willis's "Common Culture" and W. A. Gamson's "Talking Politics." Argues that both studies find that people make their own uses of media. (SR)

Predicting the ungauged basin: model validation and realism assessment

NASA Astrophysics Data System (ADS)

van Emmerik, Tim; Mulder, Gert; Eilander, Dirk; Piet, Marijn; Savenije, Hubert

2016-04-01

The hydrological decade on Predictions in Ungauged Basins (PUB) [1] led to many new insights in model development, calibration strategies, data acquisition and uncertainty analysis. Due to a limited amount of published studies on genuinely ungauged basins, model validation and realism assessment of model outcome has not been discussed to a great extent. With this study [2] we aim to contribute to the discussion on how one can determine the value and validity of a hydrological model developed for an ungauged basin. As in many cases no local, or even regional, data are available, alternative methods should be applied. Using a PUB case study in a genuinely ungauged basin in southern Cambodia, we give several examples of how one can use different types of soft data to improve model design, calibrate and validate the model, and assess the realism of the model output. A rainfall-runoff model was coupled to an irrigation reservoir, allowing the use of additional and unconventional data. The model was mainly forced with remote sensing data, and local knowledge was used to constrain the parameters. Model realism assessment was done using data from surveys. This resulted in a successful reconstruction of the reservoir dynamics, and revealed the different hydrological characteristics of the two topographical classes. We do not present a generic approach that can be transferred to other ungauged catchments, but we aim to show how clever model design and alternative data acquisition can result in a valuable hydrological model for ungauged catchments. [1] Sivapalan, M., Takeuchi, K., Franks, S., Gupta, V., Karambiri, H., Lakshmi, V., et al. (2003). IAHS decade on predictions in ungauged basins (PUB), 2003-2012: shaping an exciting future for the hydrological sciences. Hydrol. Sci. J. 48, 857-880. doi: 10.1623/hysj.48.6.857.51421 [2] van Emmerik, T., Mulder, G., Eilander, D., Piet, M. and Savenije, H. (2015). Predicting the ungauged basin: model validation and realism assessment

[Dispositional optimism, pessimism and realism in technological potential entrepreneurs].

PubMed

López Puga, Jorge; García García, Juan

2011-11-01

Optimism has been classically considered a key trait in entrepreneurs' personality but it has been studied from a psychological point of view only in recent years. The main aim of this research is to study the relationship between dispositional optimism, pessimism and realism as a function of the tendency to create technology-based businesses. A sample of undergraduate students (n= 205) filled in an electronic questionnaire containing the Life Orientation Test-Revised after they were classified as potential technological entrepreneurs, potential general entrepreneurs and non-potential entrepreneurs. Our results show that technology-based entrepreneurs are more optimistic than non-potential entrepreneurs, whereas there were no statistical differences in pessimism and realism. The results are interpreted theoretically to define the potential entrepreneur and, from an applied perspective, to design training programmes to support future technological entrepreneurs.

Realism on the rocks: Novel success and James Hutton's theory of the earth.

PubMed

Rossetter, Thomas

2018-02-01

In this paper, I introduce a new historical case study into the scientific realism debate. During the late-eighteenth century, the Scottish natural philosopher James Hutton made two important successful novel predictions. The first concerned granitic veins intruding from granite masses into strata. The second concerned what geologists now term "angular unconformities": older sections of strata overlain by younger sections, the two resting at different angles, the former typically more inclined than the latter. These predictions, I argue, are potentially problematic for selective scientific realism in that constituents of Hutton's theory that would not be considered even approximately true today played various roles in generating them. The aim here is not to provide a full philosophical analysis but to introduce the case into the debate by detailing the history and showing why, at least prima facie, it presents a problem for selective realism. First, I explicate Hutton's theory. I then give an account of Hutton's predictions and their confirmations. Next, I explain why these predictions are relevant to the realism debate. Finally, I consider which constituents of Hutton's theory are, according to current beliefs, true (or approximately true), which are not (even approximately) true, and which were responsible for these successes. Copyright © 2017 The Author. Published by Elsevier Ltd.. All rights reserved.

Get real: how current behavior influences perceptions of realism and behavioral intent for public service announcements.

PubMed

Nelson, Michelle R; Zhu, Xuan; Li, Yingying; Fiese, Barbara; Koester, Brenda

2015-01-01

This research examined how realism and current behavior influence message reception and processing for public service announcements (PSAs) designed to help parents with meal planning. Findings from 19 in-depth interviews revealed that the perceived realism of the message, the similarity, and the wishful identification with informants' lives influenced message acceptance, in line with the Message Interpretation Process (MIP) model. Results of an online survey with mothers show that realism matters more for those individuals who already engage in the featured behavior. In line with theory, "experts" (meal planners) show increased behavioral intent of the featured behaviors when viewing the more realistic PSA.

Ontological and Epistemic Claims of Realism and Instrumentalism

ERIC Educational Resources Information Center

Lau, Michael Y.

2005-01-01

This article presents comments on "Realism, Instrumentalism, and Scientific Symbiosis: Psychological Theory as a Search for Truth and the Discovery of Solutions" by John T. Cacioppo, Gun R. Semin and Gary G. Berntson. While Lau admires the authors efforts to negotiate symbiosis with seemingly incommensurate realist and instrumentalist positions in…

Three Forms of Neuro-Realism: Explaining the Persistence of the "Uncritically Real" in Popular Neuroscience News

ERIC Educational Resources Information Center

Gruber, David R.

2017-01-01

Neuro-realism is a widely cited concept describing a textual phenomenon in popular science news wherein brain research uncritically validates or invalidates the "realness" of particular beliefs or practices. Currently, no research on neuro-realism examines the variable rhetorical roles of such statements, that is, how they support…

Nosology, ontology and promiscuous realism.

PubMed

Binney, Nicholas

2015-06-01

Medics may consider worrying about their metaphysics and ontology to be a waste of time. I will argue here that this is not the case. Promiscuous realism is a metaphysical position which holds that multiple, equally valid, classification schemes should be applied to objects (such as patients) to capture different aspects of their complex and heterogeneous nature. As medics at the bedside may need to capture different aspects of their patients' problems, they may need to use multiple classification schemes (multiple nosologies), and thus consider adopting a different metaphysics to the one commonly in use. © 2014 John Wiley & Sons, Ltd.

An Exploration of Adolescents' Perceptions of Videogame Realism

ERIC Educational Resources Information Center

Malliet, Steven

2006-01-01

An attempt is made to translate the concept of perceived realism from the domain of general media studies to the domain of videogame studies. In order to make such a translation, a thorough knowledge and integration is required of the simulation aspects that distinguish videogames from older media such as film or television. The different meanings…

Pragmatic critical realism: could this methodological approach expand our understanding of employment relations?

PubMed

Mearns, Susan Lesley

2011-01-01

This paper seeks to highlight the need for employment relations academics and researchers to expand their use of research methodologies in order for them to enable the advancement of theoretical debate within their discipline. It focuses on the contribution that pragmatical critical realism has made to the field of perception and argues that it would add value to the subject of employment relations. It is a theoretically centred review of pragmatical critical realism and the possible contribution this methodology would make to the field of employment relations. The paper concludes that the employment relationship does not take place in a vacuum rather it is focussed on the interaction between imperfect individuals. Therefore, their interactions are moulded by emotions which can not be explored thoroughly or even acknowledged through a positivists' rigorous but limited acknowledgment of what constitutes 'knowledge' and development of theory. While not rejecting the contribution that quantitative data or positivism have made to the field, the study concludes that pragmatic critical realism has a lot to offer the development of the area and its theoretical foundations.

Effect of fenoterol stereochemistry on the β2 adrenergic receptor system: ligand-directed chiral recognition.

PubMed

Jozwiak, Krzysztof; Plazinska, Anita; Toll, Lawrence; Jimenez, Lucita; Woo, Anthony Yiu-Ho; Xiao, Rui-Ping; Wainer, Irving W

2011-01-01

The β(2) adrenergic receptor (β(2)-AR) is a model system for studying the ligand recognition process in G protein-coupled receptors. Fenoterol (FEN) is a β(2)-AR selective agonist that has two centers of chirality and exists as four stereoisomers. Radioligand binding studies determined that stereochemistry greatly influences the binding affinity. Subsequent Van't Hoff analysis shows very different thermodynamics of binding depending on the stereoconfiguration of the molecule. The binding of (S,x')-isomers is almost entirely enthalpy controlled whereas binding of (R,x')-isomers is purely entropy driven. Stereochemistry of FEN molecule also affects the coupling of the receptor to different G proteins. In a rat cardiomyocyte contractility model, (R,R')-FEN was shown to selectively activate G(s) protein signaling while the (S,R')-isomer activated both G(i) and G(s) protein. The overall data demonstrate that the chirality at the two chiral centers of the FEN molecule influences the magnitude of binding affinity, thermodynamics of local interactions within the binding site, and the global mechanism of β(2)-AR activation. Differences in thermodynamic parameters and nonuniform G-protein coupling suggest a mechanism of chiral recognition in which observed enantioselectivities arise from the interaction of the (R,x')-FEN stereoisomers with a different receptor conformation than the one with which the (S,x')-isomer interacts. Copyright © 2011 Wiley-Liss, Inc.

Practical Stereochemistry.

PubMed

Kellogg, Richard M

2017-04-18

The relationship between fundamental and applied is often uneasy, particularly in modern political climates. A familiar political view, aimed negatively at the scientific community, is that the former is a waste of money whereas the latter gives value for investment. The answer that fundamental is required as the basis for practical suffers from the fact that the timelines between fundamental and practical are often long and the routes contorted and unexpected. This has been my experience. In this Account, examples are given from the research in which I have been involved wherein quite fundamental considerations have led to various applications. The longer the time, the clearer and broader the relationship. Fundamental can and does lead to application. They need and depend on each other. I have seen this both from the side of academia and from small companies. In the course of the past 40 plus years, I have been involved in various aspects of stereochemistry and, in particular, chirality. It has been rewarding to see that several of the developments, most originally grounded in fundamental research considerations, have been used in the chemical community and given new dimensions and often practical applications by others. In this Account, a path-not planned deliberately by me-from orbital symmetry and Woodward-Hoffmann rules through crown ethers to conformational analysis to diastereomeric resolutions to deracemizations powered by Ostwald ripening and the Gibbs-Thomson effect to nucleation to helicenes is described. In order of discussion, the orbital symmetry aspects have via an unusual and unpredicted path has resulted in, among other things, a synthesis of hindered alkenes useful for the production of molecular motors. The crown ether aspects led to discovery of the utility of cesium salts particularly for racemization sensitive nucleophilic substitutions. Work on diastereomeric resolutions has concentrated on the mechanistic as well as practical

Single Stage Tandem Mass Spectrometry Assignment of the C-5 Uronic Acid Stereochemistry in Heparan Sulfate Tetrasaccharides using Electron Detachment Dissociation

NASA Astrophysics Data System (ADS)

Agyekum, Isaac; Zong, Chengli; Boons, Geert-Jan; Amster, I. Jonathan

2017-09-01

The analysis of heparan sulfate (HS) glycosaminoglycans presents many challenges, due to the high degree of structural heterogeneity arising from their non-template biosynthesis. Complete structural elucidation of glycosaminoglycans necessitates the unambiguous assignments of sulfo modifications and the C-5 uronic acid stereochemistry. Efforts to develop tandem mass spectrometric-based methods for the structural analysis of glycosaminoglycans have focused on the assignment of sulfo positions. The present work focuses on the assignment of the C-5 stereochemistry of the uronic acid that lies closest to the reducing end. Prior work with electron-based tandem mass spectrometry methods, specifically electron detachment dissociation (EDD), have shown great promise in providing stereo-specific product ions, such as the B3 ´ -CO2, which has been found to distinguish glucuronic acid (GlcA) from iduronic acid (IdoA) in some HS tetrasaccharides. The previously observed diagnostic ions are generally not observed with 2- O-sulfo uronic acids or for more highly sulfated heparan sulfate tetrasaccharides. A recent study using electron detachment dissociation and principal component analysis revealed a series of ions that correlate with GlcA versus IdoA for a set of 2- O-sulfo HS tetrasaccharide standards. The present work comprehensively investigates the efficacy of these ions for assigning the C-5 stereochemistry of the reducing end uronic acid in 33 HS tetrasaccharides. A diagnostic ratio can be computed from the sum of the ions that correlate to GlcA to those that correlate to IdoA. [Figure not available: see fulltext.

Measurement contextuality is implied by macroscopic realism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Zeqian; Montina, A.; Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, Ontario, N2L 2Y5

2011-04-15

Ontological theories of quantum mechanics provide a realistic description of single systems by means of well-defined quantities conditioning the measurement outcomes. In order to be complete, they should also fulfill the minimal condition of macroscopic realism. Under the assumption of outcome determinism and for Hilbert space dimension greater than 2, they were all proved to be contextual for projective measurements. In recent years a generalized concept of noncontextuality was introduced that applies also to the case of outcome indeterminism and unsharp measurements. It was pointed out that the Beltrametti-Bugajski model is an example of measurement noncontextual indeterminist theory. Here wemore » provide a simple proof that this model is the only one with such a feature for projective measurements and Hilbert space dimension greater than 2. In other words, there is no extension of quantum theory providing more accurate predictions of outcomes and simultaneously preserving the minimal labeling of events through projective operators. As a corollary, noncontextuality for projective measurements implies noncontextuality for unsharp measurements. By noting that the condition of macroscopic realism requires an extension of quantum theory, unless a breaking of unitarity is invoked, we arrive at the conclusion that the only way to solve the measurement problem in the framework of an ontological theory is by relaxing the hypothesis of measurement noncontextuality in its generalized sense.« less

Stereochemistry of quinoxaline antagonist binding to a glutamate receptor investigated by Fourier transform infrared spectroscopy.

PubMed

Madden, D R; Thiran, S; Zimmermann, H; Romm, J; Jayaraman, V

2001-10-12

The stereochemistry of the interactions between quinoxaline antagonists and the ligand-binding domain of the glutamate receptor 4 (GluR4) have been investigated by probing their vibrational modes using Fourier transform infrared spectroscopy. In solution, the electron-withdrawing nitro groups of both compounds establish a resonance equilibrium that appears to stabilize the keto form of one of the cyclic amide carbonyl bonds. Changes in the 6,7-dinitro-2,3-dihydroxyquinoxaline vibrational spectra on binding to the glutamate receptor, interpreted within the framework of a published crystal structure, illuminate the stereochemistry of the interaction and suggest that the binding site imposes a more polarized electronic bonding configuration on this antagonist. Similar spectral changes are observed for 6-cyano-7-dinitro-2,3-dihydroxyquinoxaline, confirming that its interactions with the binding site are highly similar to those of 6,7-dinitro-2,3-dihydroxyquinoxaline and leading to a model of the 6-cyano-7-dinitro-2,3-dihydroxyquinoxaline-S1S2 complex, for which no crystal structure is available. Conformational changes within the GluR ligand binding domain were also monitored. Compared with the previously reported spectral changes seen on binding of the agonist glutamate, only a relatively small change is detected on antagonist binding. This correlation between the functional effects of different classes of ligand and the magnitude of the spectroscopic changes they induce suggests that the spectral data reflect physiologically relevant conformational processes.

Exploring the relationship between object realism and object-based attention effects.

PubMed

Roque, Nelson; Boot, Walter R

2015-09-01

Visual attention prioritizes processing of locations in space, and evidence also suggests that the benefits of attention can be shaped by the presence of objects (object-based attention). However, the prevalence of object-based attention effects has been called into question recently by evidence from a large-sampled study employing classic attention paradigms (Pilz et al., 2012). We conducted two experiments to explore factors that might determine when and if object-based attention effects are observed, focusing on the degree to which the concreteness and realism of objects might contribute to these effects. We adapted the classic attention paradigm first reported by Egly, Driver, and Rafal (1994) by replacing abstract bar stimuli in some conditions with objects that were more concrete and familiar to participants: items of silverware. Furthermore, we varied the realism of these items of silverware, presenting either cartoon versions or photo-realistic versions. Contrary to predictions, increased realism did not increase the size of object-based effects. In fact, no clear object-based effects were observed in either experiment, consistent with previous failures to replicate these effects in similar paradigms. While object-based attention may exist, and may have important influences on how we parse the visual world, these and other findings suggest that the two-object paradigm typically relied upon to study object-based effects may not be the best paradigm to investigate these issues. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of fenoterol stereochemistry on the β2 adrenergic receptor system: ligand directed chiral recognition

PubMed Central

Jozwiak, Krzysztof; Plazinska, Anita; Toll, Lawrence; Jimenez, Lucita; Woo, Anthony Yiu-Ho; Xiao, Rui-Ping; Wainer, Irving W.

2011-01-01

The β2 adrenergic receptor (β2-AR) is a model system for studying the ligand recognition process in G-protein coupled receptors. Fenoterol (FEN) is a β2-AR selective agonist that has two centers of chirality and exists as four stereoisomers. Radioligand binding studies determined that stereochemistry greatly influences the binding affinity. Subsequent Van’t Hoff analysis shows very different thermodynamics of binding depending on the stereoconfiguration of the molecule. The binding of (S,x’)-isomers is almost entirely enthalpy controlled whereas binding of (R,x’)-isomers is purely entropy driven. Stereochemistry of FEN molecule also affects the coupling of the receptor to different G proteins. In a rat cardiomyocyte contractility model, (R,R’)-FEN was shown to selectively activate Gs protein signaling while the (S,R’)- isomer activated both Gi and Gs protein. The overall data demonstrate that the chirality at the two chiral centers of the FEN molecule influences the magnitude of binding affinity, thermodynamics of local interactions within the binding site and the global mechanism of β2-AR activation. Differences in thermodynamic parameters and non-uniform G-protein coupling suggest a mechanism of chiral recognition in which observed enantioselectivities arise from the interaction of the (R,x’)-FEN stereoisomers with a different receptor conformation than the one with which the (S,x’)-isomer interacts. PMID:21618615

Design and Implementation of a Self-Directed Stereochemistry Lesson Using Embedded Virtual Three-Dimensional Images in a Portable Document Format

ERIC Educational Resources Information Center

Cody, Jeremy A.; Craig, Paul A.; Loudermilk, Adam D.; Yacci, Paul M.; Frisco, Sarah L.; Milillo, Jennifer R.

2012-01-01

A novel stereochemistry lesson was prepared that incorporated both handheld molecular models and embedded virtual three-dimensional (3D) images. The images are fully interactive and eye-catching for the students; methods for preparing 3D molecular images in Adobe Acrobat are included. The lesson was designed and implemented to showcase the 3D…

THE INTERSECTION OF INDEPENDENT LIES: INCREASING REALISM IN ECOLOGICAL RISK ASSESSMENT

EPA Science Inventory

In 1966, Levins presented a philosophical discussion on making inference about populations using clusters of models. In this article we provide an overview of model inference in ecological risk assessment, discuss the benefits and trade-offs of increasing model realism, show the...

The Acquisition of Stereochemical Knowledge by Algerian Students Intending to Teach Physical Sciences

ERIC Educational Resources Information Center

Boukhechem, Mohamed-Salah; Dumon, Alain; Zouikri, Mohamed

2011-01-01

In this work we evaluated the level of difficulty found in learning stereochemistry concepts, by students intending to teach physical sciences at the Ecole Normale Superieure (ENS) Kouba (Algeria). A paper and pencil questionnaire was administered to 170 students to evaluate: their familiarity with Newman representations; their ability of linking…

Kinetics and stereochemistry of LinB-catalyzed δ-HBCD transformation: Comparison of in vitro and in silico results.

PubMed

Heeb, Norbert V; Mazenauer, Manuel; Wyss, Simon; Geueke, Birgit; Kohler, Hans-Peter E; Lienemann, Peter

2018-05-12

LinB is a haloalkane dehalogenase found in Sphingobium indicum B90A, an aerobic bacterium isolated from contaminated soils of hexachlorocyclohexane (HCH) dumpsites. We showed that this enzyme also converts hexabromocyclododecanes (HBCDs). Here we give new insights in the kinetics and stereochemistry of the enzymatic transformation of δ-HBCD, which resulted in the formation of two pentabromocyclododecanols (PBCDols) as first- (P 1δ , P 2δ ) and two tetrabromocyclododecadiols (TBCDdiols) as second-generation products (T 1δ , T 2δ ). Enzymatic transformations of δ-HBCD, α 1 -PBCDol, one of the transformation products, and α 2 -PBCDol, its enantiomer, were studied and modeled with Michaelis-Menten (MM) kinetics. Respective MM-parameters K M , v max , k cat /K M indicated that δ-HBCD is the best LinB substrate followed by α 2 - and α 1 -PBCDol. The stereochemistry of these transformations was modeled in silico, investigating respective enzyme-substrate (ES) and enzyme-product (EP) complexes. One of the four predicted ES-complexes led to the PBCDol product P 1δ , identical to α 2 -PBCDol with the 1R,2R,5S,6R,9R,10S-configuration. An S N 2-like substitution of bromine at C6 of δ-HBCD by Asp-108 of LinB and subsequent hydrolysis of the alkyl-enzyme led to α 2 -PBCDol. Modeling results further indicate that backside attacks at C1, C9 and C10 are reasonable too, selectively binding leaving bromide ions in a halide pocket found in LinB. Docking with α 2 -PBCDol, also allowed productive enzyme binding. A TBCD-1,5-diol with the 1S,2S,5R,6R,9S,10R-configuration is the predicted second-generation product T 1δ . In conclusion, in vitro- and in silico findings now allow a detailed description of step-wise enzymatic dehalohydroxylation reactions of δ-HBCD to specific PBCDols and TBCDdiols at Å-resolution and predictions of their stereochemistry. Copyright © 2018 Elsevier Ltd. All rights reserved.

Decoherence-free emergence of macroscopic local realism for entangled photons in a cavity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Portolan, S.; Rossi, F.; Di Stefano, O.

2006-02-15

We investigate the influence of environmental noise on polarization entangled light generated by parametric emission in a cavity. By adopting a recent separability criterion, we show that (i) self-stimulation may suppress the detrimental influence of noise on entanglement, but (ii) once it becomes effective, a noise-equipped classical model of parametric emission provides the same results of quantum theory with respect to the separability criterion. More generally we also show that, in the macroscopic limit, it is not possible to observe violations of local realism with measurements of finite order n-particle correlations only. These results provide a prototypical case of themore » emergence of macroscopic local realism in the presence of strong entanglement even in the absence of decoherence.« less

The JPL Cost Risk Analysis Approach that Incorporates Engineering Realism

NASA Technical Reports Server (NTRS)

Harmon, Corey C.; Warfield, Keith R.; Rosenberg, Leigh S.

2006-01-01

This paper discusses the JPL Cost Engineering Group (CEG) cost risk analysis approach that accounts for all three types of cost risk. It will also describe the evaluation of historical cost data upon which this method is based. This investigation is essential in developing a method that is rooted in engineering realism and produces credible, dependable results to aid decision makers.

Correlation between the Stereochemistry and Bioactivity in Octahedral Rhodium Prolinato Complexes.

PubMed

Rajaratnam, Rajathees; Martin, Elisabeth K; Dörr, Markus; Harms, Klaus; Casini, Angela; Meggers, Eric

2015-08-17

Controlling the relative and absolute configuration of octahedral metal complexes constitutes a key challenge that needs to be overcome in order to fully exploit the structural properties of octahedral metal complexes for applications in the fields of catalysis, materials sciences, and life sciences. Herein, we describe the application of a proline-based chiral tridentate ligand to decisively control the coordination mode of an octahedral rhodium(III) complex. We demonstrate the mirror-like relationship of synthesized enantiomers and differences between diastereomers. Further, we demonstrate, using the established pyridocarbazole pharmacophore ligand as part of the organometallic complexes, the importance of the relative and absolute stereochemistry at the metal toward chiral environments like protein kinases. Protein kinase profiling and inhibition data confirm that the proline-based enantiopure rhodium(III) complexes, despite having all of the same constitution, differ strongly in their selectivity properties despite their unmistakably mutual origin. Moreover, two exemplary compounds have been shown to induce different toxic effects in an ex vivo rat liver model.

Control of phosphorothioate stereochemistry substantially increases the efficacy of antisense oligonucleotides.

PubMed

Iwamoto, Naoki; Butler, David C D; Svrzikapa, Nenad; Mohapatra, Susovan; Zlatev, Ivan; Sah, Dinah W Y; Meena; Standley, Stephany M; Lu, Genliang; Apponi, Luciano H; Frank-Kamenetsky, Maria; Zhang, Jason Jingxin; Vargeese, Chandra; Verdine, Gregory L

2017-09-01

Whereas stereochemical purity in drugs has become the standard for small molecules, stereoisomeric mixtures containing as many as a half million components persist in antisense oligonucleotide (ASO) therapeutics because it has been feasible neither to separate the individual stereoisomers, nor to synthesize stereochemically pure ASOs. Here we report the development of a scalable synthetic process that yields therapeutic ASOs having high stereochemical and chemical purity. Using this method, we synthesized rationally designed stereopure components of mipomersen, a drug comprising 524,288 stereoisomers. We demonstrate that phosphorothioate (PS) stereochemistry substantially affects the pharmacologic properties of ASOs. We report that Sp-configured PS linkages are stabilized relative to Rp, providing stereochemical protection from pharmacologic inactivation of the drug. Further, we elucidated a triplet stereochemical code in the stereopure ASOs, 3'-SpSpRp, that promotes target RNA cleavage by RNase H1 in vitro and provides a more durable response in mice than stereorandom ASOs.

Hope Less: How a Healthy Dose of Realism Can Help in the ICU.

PubMed

Reis, Elizabeth

2014-01-01

The author's father died recently after a sudden heart attack. This essay discusses how the family's experiences in the cardiac intensive care unit surprised her, even though she is a member of the Ethics Committee and the Ethics Consult Team at her local hospital, and how this led her to reconsider the ways in which families and hospital physicians communicate about the process of dying. How should doctors balance their messages of hope and realism when the situation is grim? Important judgment calls needed to be made, yet the family did not fully understand what they needed to know to make good decisions, especially the importance of the timing of their decisions. A conversation early on about what would happen if the patient became physically stable--no matter how impaired--while all options remained on the table might usefully (and mercifully) transform hope at the end.

The Cultural Work of Magical Realism in Three Young Adult Novels

ERIC Educational Resources Information Center

Latham, Don

2007-01-01

Magical realism as a literary mode is often subversive and transgressive, questioning the values and assumptions of the dominant society that it depicts. Young adult literature, by contrast, is typically thought to serve a socializing function, helping to integrate young readers into adult society. What then is the cultural work of magical realism…

Ecological Realism of US EPA Experimental Stream Facility ...

EPA Pesticide Factsheets

The USEPA’s Experimental Stream Facility (ESF) conducts meso-scale ecotoxicology studies that account for both structural and functional responses of whole stream communities to contaminants or other stressors. The 16 mesocosms of ESF are indoors and consist of a tiled run section (0.152 m W x 4.268 m L x 0.105 m D) that widens to a gravel riffle section (0.305 m W x 4.268 m L x 0.19 m D). They are intermediate size among studies reporting stream mesocosm results. Their set-up is unique for their size, with a high degree of engineering controls for continuous flow-through dose-response designs, yet fixed, chronic exposures to contaminants under conditions that quantifiably mimic real stream riffle/run habitat with consistent upstream renewal. With fifty standard operating procedures serving ESF studies, the background and boundary condition information is collected to determine the realism critical to the field relevance of the results. Parallel ex situ and in situ single species exposure formats including fish survival and fecundity metrics are also included. With this framework studies at ESF provide scientifically defensible evaluation of proposed aquatic life criteria. This presentation discusses the relevance and realism of USEPA's mesocosms studies conducted using the Experimental Stream Facility in Milford, OH within the context of understanding the role meso-scale results can play in validating aquatic life criteria for streams and, more generally, man

Orbital State Uncertainty Realism

NASA Astrophysics Data System (ADS)

Horwood, J.; Poore, A. B.

2012-09-01

Fundamental to the success of the space situational awareness (SSA) mission is the rigorous inclusion of uncertainty in the space surveillance network. The *proper characterization of uncertainty* in the orbital state of a space object is a common requirement to many SSA functions including tracking and data association, resolution of uncorrelated tracks (UCTs), conjunction analysis and probability of collision, sensor resource management, and anomaly detection. While tracking environments, such as air and missile defense, make extensive use of Gaussian and local linearity assumptions within algorithms for uncertainty management, space surveillance is inherently different due to long time gaps between updates, high misdetection rates, nonlinear and non-conservative dynamics, and non-Gaussian phenomena. The latter implies that "covariance realism" is not always sufficient. SSA also requires "uncertainty realism"; the proper characterization of both the state and covariance and all non-zero higher-order cumulants. In other words, a proper characterization of a space object's full state *probability density function (PDF)* is required. In order to provide a more statistically rigorous treatment of uncertainty in the space surveillance tracking environment and to better support the aforementioned SSA functions, a new class of multivariate PDFs are formulated which more accurately characterize the uncertainty of a space object's state or orbit. The new distribution contains a parameter set controlling the higher-order cumulants which gives the level sets a distinctive "banana" or "boomerang" shape and degenerates to a Gaussian in a suitable limit. Using the new class of PDFs within the general Bayesian nonlinear filter, the resulting filter prediction step (i.e., uncertainty propagation) is shown to have the *same computational cost as the traditional unscented Kalman filter* with the former able to maintain a proper characterization of the uncertainty for up to *ten

Depressive Realism and Attributional Style: Implications for Individuals at Risk for Depression

ERIC Educational Resources Information Center

Moore, Michael T.; Fresco, David M.

2007-01-01

Prior research has found that depressed individuals are more realistic in their interpretations of certain events than nondepressed individuals. However, the implications of this finding for the etiology of depressive disorders have never been clarified. The current investigation sought to remedy this situation by exploring realism in the context…

Synthesis of precursors to and spectroscopic characterization of highly unsaturated carbenes and diradicals and development and implementation of a web-based stereochemistry tutorial

NASA Astrophysics Data System (ADS)

Burrmann, Nicola Jean

A variety of substituted diynols, diynals, and diynones have been prepared en route to the synthesis of precursors to dialkynyl carbenes (R1--C≡C--C--C≡C--R 2). In light of the unique reactivity associated with these simple systems, several strategies were required to assemble the carbon backbones (Chapter I). Tosylhydrazone and trisylhydrazone precursors to 2-diazo-3-pentyne ( 1), 2-diazo-3-butyne (2), and Idiazo-2-butyne ( 3) were synthesized and then converted into their respective diazo compounds. Various attempts to study these diazo compounds using matrix isolation IR and EPR spectroscopy were made and proved to be unsuccessful. Computations were done to characterize the C5H6 potential energy surface, as well as to determine the IR vibrational frequencies of the isomers on this surface (Chapter 2). A web-based Stereochemistry Tutorial that details the core definitions and structural representations relevant to organic stereochemistry was designed and implemented into several introductory-level organic chemistry classes. This tutorial also allows for students to select their preferred structural representation and method for making stereochemical comparisons between molecules. The tutorial was evaluated, either qualitatively, quantitatively, or both, by students in three different introductory organic chemistry courses at the University of Wisconsin---Madison. The data show that students did use a variety of different methods for making stereochemical comparisons between molecules, and that prior exposure to lectures on stereochemistry by the course professor strongly influenced these choices. Furthermore, the level of improvement in stereochemical knowledge as a result of using only the tutorial was comparable to, or higher than, that achieved by students who were only exposed to lectures by the course professor, regardless of the method chosen for making stereochemical comparisons between molecules (Chapter 3)

Experimental Limits on Local Realism with Separable and Entangled Photons

DTIC Science & Technology

2011-01-01

DATES COVERED (From - To) OCT 2009 – SEP 2011 4. TITLE AND SUBTITLE EXPERIMENTAL LIMITS ON LOCAL REALISM WITH SEPARABLE AND ENTANGLED PHOTONS 5a...realization of the quantum state must be chosen. Entangled photons or electrons provide the most viable choices. In this work we consider a simplified...fewer measurements, and is more advantageous in its conceptual clarity. 15. SUBJECT TERMS polarization- entangled photons , Bell inequalities, local

Happiness, Psychology, and Degrees of Realism

PubMed Central

Lavazza, Andrea

2016-01-01

The recent emphasis on a realist ontology that cannot be overshadowed by subjectivist or relativist perspectives seems to have a number of consequences for psychology as well. My attempt here is to analyse the relationship between happiness as a state of the individual and the states of the external world and the brain events related to (or, in some hypotheses, causally responsible for) its occurrence. It can be maintained that different degrees of realism are suitable to describe the states of happiness and this fact might have relevant psychological implications, namely for the so-called positive psychology. This is especially true now that there are methods available to induce subjective states of happiness unrelated to the external conditions usually taken to be linked to such states. PMID:27536261

Positioning positivism, critical realism and social constructionism in the health sciences: a philosophical orientation.

PubMed

Cruickshank, Justin

2012-03-01

Positioning positivism, critical realism and social constructionism in the health sciences: a philosophical orientation This article starts by considering the differences within the positivist tradition and then it moves on to compare two of the most prominent schools of postpositivism, namely critical realism and social constructionism. Critical realists hold, with positivism, that knowledge should be positively applied, but reject the positivist method for doing this, arguing that causal explanations have to be based not on empirical regularities but on references to unobservable structures. Social constructionists take a different approach to postpositivism and endorse a relativist rejection of truth and hold that the task of research is to foster a scepticism that undermines any positive truth claim made. It is argued that social constructionism is a contradictory position. © 2011 Blackwell Publishing Ltd.

Critical realism and psychiatric nursing: a philosophical inquiry.

PubMed

Littlejohn, Christopher

2003-09-01

There is a tension within contemporary psychiatric nursing between those who would embrace the knowledge and methods of psychiatry and psychology, and those who instead argue for the development of an autonomous nursing profession. This tension cannot be resolved by way of the underpinning philosophies of these positions, namely empiricism and idealism. Instead, critical realism, positioned between these philosophies offers a methodology through which to seek a new paradigm. This paper aims to determine whether psychiatric nursing has the potential to exist as an independent and autonomous profession, concerned with providing a helping response to those in mental distress. The paper asks critical realism's transcendental question in order to identify the a priori requirements of an autonomous psychiatric nursing, independent of both psychiatry and psychology. Consideration of these a priori requirements includes selected information from contemporary texts in order to identify potentially helpful nursing responses to mental distress, as opposed to the theorising that surrounds these helping responses. The theories of psychiatry and psychology are neither necessary nor sufficient in providing a foundation for an autonomous psychiatric nursing. While medications have an intrinsic helpfulness for some people, for some of their problems, for some of the time, this does not illuminate the causes of mental distress. There is an intrinsic helping response in human interpersonal communication, yet this is not specific to 'psychotherapy' and does not 'belong' solely to psychotherapists. Support is found for an autonomous and independent profession of psychiatric nursing, able to provide a helping response to those in mental distress independent of psychiatry and psychology.

Conflict: Operational Realism versus Analytical Rigor in Defense Modeling and Simulation

DTIC Science & Technology

2012-06-14

Campbell, Experimental and Quasi- Eperimental Designs for Generalized Causal Inference, Boston: Houghton Mifflin Company, 2002. [7] R. T. Johnson, G...experimentation? In order for an experiment to be considered rigorous, and the results valid, the experiment should be designed using established...addition to the interview, the pilots were administered a written survey, designed to capture their reactions regarding the level of realism present

Standpoint Theory, Realism and the Search for Objectivity in the Sociology of Education

ERIC Educational Resources Information Center

Edwards, Gail

2014-01-01

This paper evaluates the contribution of "social realism" in resolving questions of knowledge and curriculum in the sociology of education. Social realists argue that, in the interests of educational equality, all pupils should have access to "powerful" knowledge produced by specialist intellectual communities. Social realism…

Bell inequalities for falsifying mesoscopic local realism via amplification of quantum noise

NASA Astrophysics Data System (ADS)

Reid, M. D.

2018-04-01

Macroscopic realism (MR) per se specifies that a system which has two macroscopically distinct states available to it (such as a cat being dead or alive) is at all times predetermined to be in one or other of those two states. A minimal assumption of a macroscopic realistic theory therefore is the validity of a hidden variable λM that predetermines the outcome (whether dead or alive) of a measurement M ̂ distinguishing the two states. Proposals to test MR generally introduce a second premise to further qualify the meaning of MR. Thus, we consider a model, macroscopic local realism (MLR), where the second premise is that measurements at one location cannot cause an instantaneous macroscopic change δ to the results of measurements made on a second system at another location. To provide a practical test, we define the intermediate concept of δ -scopic local realism (δ -LR), where δ ≠0 can be quantified, but need not be macroscopic. By considering the amplification of quantum fluctuations, we show how negation of δ -LR is possible using fields violating a continuous variable Bell inequality. A modified Bell-Clauser-Horne-Shimony-Holt inequality is derived that tests δ -LR, and a quantitative proposal given for experiments based on polarization entanglement. In the proposal, δ is the magnitude of the quantum noise scaled by an adjustable coherent amplitude α that can also be considered part of the measurement apparatus. Thus, δ is large in an absolute sense, but scales inversely with the square root of the system size, which is proportional to |α| 2. We discuss how the proposed experiment gives a realization of a type of Schrödinger-cat experiment without problems of decoherence.

Mapping new theoretical and methodological terrain for knowledge translation: contributions from critical realism and the arts

PubMed Central

Kontos, Pia C; Poland, Blake D

2009-01-01

Background Clinical practice guidelines have been a popular tool for the improvement of health care through the implementation of evidence from systematic research. Yet, it is increasingly clear that knowledge alone is insufficient to change practice. The social, cultural, and material contexts within which practice occurs may invite or reject innovation, complement or inhibit the activities required for success, and sustain or alter adherence to entrenched practices. However, knowledge translation (KT) models are limited in providing insight about how and why contextual contingencies interact, the causal mechanisms linking structural aspects of context and individual agency, and how these mechanisms influence KT. Another limitation of KT models is the neglect of methods to engage potential adopters of the innovation in critical reflection about aspects of context that influence practice, the relevance and meaning of innovation in the context of practice, and the identification of strategies for bringing about meaningful change. Discussion This paper presents a KT model, the Critical Realism and the Arts Research Utilization Model (CRARUM), that combines critical realism and arts-based methodologies. Critical realism facilitates understanding of clinical settings by providing insight into the interrelationship between its structures and potentials, and individual action. The arts nurture empathy, and can foster reflection on the ways in which contextual factors influence and shape clinical practice, and how they may facilitate or impede change. The combination of critical realism and the arts within the CRARUM model promotes the successful embedding of interventions, and greater impact and sustainability. Conclusion CRARUM has the potential to strengthen the science of implementation research by addressing the complexities of practice settings, and engaging potential adopters to critically reflect on existing and proposed practices and strategies for sustaining

Bell's Inequality: Revolution in Quantum Physics or Just AN Inadequate Mathematical Model?

NASA Astrophysics Data System (ADS)

Khrennikov, Andrei

The main aim of this review is to stress the role of mathematical models in physics. The Bell inequality (BI) is often called the "most famous inequality of the 20th century." It is commonly accepted that its violation in corresponding experiments induced a revolution in quantum physics. Unlike "old quantum mechanics" (of Einstein, Schrodinger Bohr, Heisenberg, Pauli, Landau, Fock), "modern quantum mechanics" (of Bell, Aspect, Zeilinger, Shimony, Green-berger, Gisin, Mermin) takes seriously so called quantum non-locality. We will show that the conclusion that one has to give up the realism (i.e., a possibility to assign results of measurements to physical systems) or the locality (i.e., to assume action at a distance) is heavily based on one special mathematical model. This model was invented by A. N. Kolmogorov in 1933. One should pay serious attention to the role of mathematical models in physics. The problems of the realism and locality induced by Bell's argument can be solved by using non-Kolmogorovian probabilistic models. We compare this situation with non-Euclidean geometric models in relativity theory.

Explanation and Quantification in Educational Research: The Arguments of Critical and Scientific Realism

ERIC Educational Resources Information Center

Nash, Roy

2005-01-01

The influence of Bhaskar's critical realism has become increasingly evident in the debate on the nature of educational research. This philosophy, dedicated to the overthrow of positivist doctrines, in particular those of empiricism, nominalism, and causation as constant conjunction, is the foundation of contemporary proposals for new perspectives…

Sociological, Postmodern, and New Realism Perspectives in Social Constructionism: Implications for Literacy Research.

ERIC Educational Resources Information Center

Hruby, George G.

2001-01-01

Offers an historical definition of social constructionism, a review of its conceptual bases, and an exploration of its epistemological implications. Describes a history comprised of three paradigmatically distinct waves: a sociological, a postmodern, and an emerging third wave grounded in new realism or neonaturalism. Suggests potential uses of…

Accuracy, Authenticity, Fidelity: Aesthetic Realism, the "Deficit Model," and the Public Understanding of Science.

PubMed

Vidal, Fernando

2018-03-01

Argument "Deficit model" designates an outlook on the public understanding and communication of science that emphasizes scientific illiteracy and the need to educate the public. Though criticized, it is still widespread, especially among scientists. Its persistence is due not only to factors ranging from scientists' training to policy design, but also to the continuance of realism as an aesthetic criterion. This article examines the link between realism and the deficit model through discussions of neurology and psychiatry in fiction film, as well as through debates about historical movies and the cinematic adaptation of literature. It shows that different values and criteria tend to dominate the realist stance in different domains: accuracy for movies concerning neurology and psychiatry, authenticity for the historical film, and fidelity for adaptations of literature. Finally, contrary to the deficit model, it argues that the cinema is better characterized by a surplus of meaning than by informational shortcomings.

A Theory of State Behavior under Threat: The Tragedy of Domestic Realism

DTIC Science & Technology

2007-03-01

Domestic realism draws upon events and concepts from history, psychology , philosophy, ethics, comparative politics, and upon the realist tradition in...Government Against the People (New York: Random House, 1976). 5 Andrew Silke, ed., Terrorists, Victims, and Society: Psychological Perspectives on...governments go about policing violence; some cases exhibit little restraint in accomplishing that.9 The fields of psychology and sociology provide

Televised Entertainment-Education to Prevent Adolescent Alcohol Use: Perceived Realism, Enjoyment, and Impact

ERIC Educational Resources Information Center

van Leeuwen, Lonneke; Renes, Reint Jan; Leeuwis, Cees

2013-01-01

Alcohol use among adolescents is a concern in the Netherlands because of its high prevalence and risks. To discourage adolescents from drinking alcohol, a televised entertainment-education (E-E) intervention was developed. This study investigated responses of adolescents on perceived realism and enjoyment of the E-E intervention, as well as its…

Correlations among experimental and theoretical NMR data to determine the absolute stereochemistry of darcyribeirine, a pentacyclic indole alkaloid isolated from Rauvolfia grandiflora

NASA Astrophysics Data System (ADS)

Cancelieri, Náuvia Maria; Ferreira, Thiago Resende; Vieira, Ivo José Curcino; Braz-Filho, Raimundo; Piló-Veloso, Dorila; Alcântara, Antônio Flávio de Carvalho

2015-10-01

Darcyribeirine (1) is a pentacyclic indole alkaloid isolated from Rauvolfia grandiflora. Stereochemistry of 1 was previously proposed based on 1D (coupling constant data) and 2D (NOESY correlations) NMR techniques, having been established a configuration 3R, 15S, and 20R (isomer 1a). Stereoisomers of 1 (i.e., 1a-1h) can be grouped into four sets of enantiomers. Carbon chemical shifts and hydrogen coupling constants were calculated using BLYP/6-31G* theory level for the eight isomers of 1. Calculated NMR data of 1a-1h were correlated with the corresponding experimental data of 1. The best correlations between theoretical and experimental carbon chemical shift data were obtained for the set of enantiomers 1e/1f to structures in the gaseous phase and considering solvent effects (using PCM and explicit models). Similar results were obtained when the same procedure was performed to correlations between theoretical and experimental coupling constant data. Finally, optical rotation calculations indicate 1e as its absolute stereochemistry. Orbital population analysis indicates that the hydrogen bonding between N-H of 1e and DMSO is due to contributions of its frontier unoccupied molecular orbitals, mainly LUMO+1, LUMO+2, and LUMO+3.

Magical realism: a cultural intervention for traumatized Hispanic children.

PubMed

De Rios, M D

1997-01-01

A case study is presented of two Spanish-speaking immigrant children who were run over in an automobile accident and hospitalized, to describe a culturally congruent play-therapy technique. Drawing on the work of Pynoos and Nader, the author argues for an anthropological approach in play therapy to create hyperaroused states for the traumatized child and to use cultural super heroes-what is termed "magical realism." Such an approach can be used with Latin American traumatized children as well as with children from other Third World countries to provide a culturally appropriate intervention to treat the psychological sequelae of trauma.

Perceived realism and Twitter use are associated with increased acceptance of cosmetic surgery among those watching reality television cosmetic surgery programs.

PubMed

Fogel, Joshua; King, Kahlil

2014-08-01

Reality television programming is a popular type of television programming, and features shows about cosmetic surgery. Social media such as Facebook and Twitter are increasingly popular methods of sharing information. The authors surveyed college students to determine among those watching reality television cosmetic surgery programs whether perceived realism or social media use was associated with attitudes toward cosmetic surgery. Participants (n=126) were surveyed about their reality television cosmetic surgery program viewing habits, their perception of the realism of reality television programming, and social media topics of Twitter and Facebook. Outcome variables were the Acceptance of Cosmetic Surgery Scales of social, intrapersonal, and consider. Perceived realism was significantly associated with increased scores on the Acceptance of Cosmetic Surgery Scale subscales of social (p=0.004), intrapersonal (p=0.03), and consider (p=0.03). Following a character from a reality television program on Twitter was significantly associated with increased social scores (p=0.04). There was no significant association of Facebook behavior with attitudes toward cosmetic surgery. Cosmetic plastic surgeons may benefit by advertising their services on cosmetic surgery reality television programs. These reality television programs portray cosmetic surgery in a positive manner, and viewers with increased perceived realism will be a potential receptive audience toward such advertising. Also, advertising cosmetic surgery services on Twitter feeds that discuss cosmetic surgery reality television programs would be potentially beneficial.

Stereochemistry of an agonist determines coupling preference of beta2-adrenoceptor to different G proteins in cardiomyocytes.

PubMed

Woo, Anthony Yiu-Ho; Wang, Tian-Bing; Zeng, Xiaokun; Zhu, Weizhong; Abernethy, Darrell R; Wainer, Irving W; Xiao, Rui-Ping

2009-01-01

A fundamental question regarding receptor-G protein interaction is whether different agonists can lead a receptor to different intracellular signaling pathways. Our previous studies have demonstrated that although most beta(2)-adrenoceptor agonists activate both G(s) and G(i) proteins, fenoterol, a full agonist of beta(2)-adrenoceptor, selectively activates G(s) protein. Fenoterol contains two chiral centers and may exist as four stereoisomers. We have synthesized a series of stereoisomers of fenoterol and its derivatives and characterized their receptor binding and pharmacological properties. We tested the hypothesis that the stereochemistry of an agonist determines selectivity of receptor coupling to different G protein(s). We found that the R,R isomers of fenoterol and methoxyfenoterol exhibited more potent effects to increase cardiomyocyte contraction than their S,R isomers. It is noteworthy that although (R,R)-fenoterol and (R,R)-methoxyfenoterol preferentially activate G(s) signaling, their S,R isomers were able to activate both G(s) and G(i) proteins as evidenced by the robust pertussis toxin sensitivities of their effects on cardiomyocyte contraction and on phosphorylation of extracellular signal-regulated kinase 1/2. The differential G protein selectivities of the fenoterol stereoisomers were further confirmed by photoaffinity labeling studies on G(s),G(i2), and G(i3) proteins. The inefficient G(i) signaling with the R,R isomers is not caused by the inability of the R,R isomers to trigger the protein kinase A (PKA)-mediated phosphorylation of the beta(2)-adrenoceptor, because the R,R isomers also markedly increased phosphorylation of the receptor at serine 262 by PKA. We conclude that in addition to receptor subtype and phosphorylation status, the stereochemistry of a given agonist plays an important role in determining receptor-G protein selectivity and downstream signaling events.

On the contributions of astroparticle physics to cosmology

NASA Astrophysics Data System (ADS)

Falkenburg, Brigitte

2014-05-01

Studying astroparticle physics sheds new light on scientific explanation and on the ways in which cosmology is empirically underdetermined or not. Astroparticle physics extends the empirical domain of cosmology from purely astronomical data to "multi-messenger astrophysics", i.e., measurements of all kinds of cosmic rays including very high energetic gamma rays, neutrinos, and charged particles. My paper investigates the ways in which these measurements contribute to cosmology and compares them with philosophical views about scientific explanation, the relation between theory and data, and scientific realism. The "standard models" of cosmology and particle physics lack of unified foundations. Both are "piecemeal physics" in Cartwright's sense, but contrary to her metaphysics of a "dappled world" the work in both fields of research aims at unification. Cosmology proceeds "top-down", from models to data and from large scale to small-scale structures of the universe. Astroparticle physics proceeds "bottom-up", from data taking to models and from subatomic particles to large-scale structures of the universe. In order to reconstruct the causal stories of cosmic rays and the nature of their sources, several pragmatic unifying strategies are employed. Standard views about scientific explanation and scientific realism do not cope with these "bottom-up" strategies and the way in which they contribute to cosmology. In addition it has to be noted that the shift to "multi-messenger astrophysics" transforms the relation between cosmological theory and astrophysical data in a mutually holistic way.

Mediated realism and the representation of a health care controversy.

PubMed

Petraglia, J

1994-01-01

Psychologists have recently identified "situated cognition" as an important issue for educators across disciplines. Accordingly, instructional technologists have been working on ways to make classroom materials more true-to-life and affectively engaging. In this article I review a study designed to investigate the ways in which differing realism conditions (delivered through interactive video) influenced users' understanding of the issue of euthanasia and the case of Dax Cowart. Based on the study's findings, I raise the issue of a possible trade-off between traditional values of objectivity and authenticity.

The Effects of Talking-Head with Various Realism Levels on Students' Emotions in Learning

ERIC Educational Resources Information Center

Mohamad Ali, Ahmad Zamzuri; Hamdan, Mohd Najib

2017-01-01

The aim of this study was to evaluate the effects of various realistic levels of talking-head on students' emotions in pronunciation learning. Four talking-head characters with varying levels of realism were developed and tested: a nonrealistic three-dimensional character, a realistic three-dimensional character, a two-dimensional character, and…

Improving the physiological realism of experimental models.

PubMed

Vinnakota, Kalyan C; Cha, Chae Y; Rorsman, Patrik; Balaban, Robert S; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A; Jeneson, Jeroen A L

2016-04-06

The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease.

Separability and Non-Individuality: Is It Possible to Conciliate (At Least A Form Of) Einstein's Realism with Quantum Mechanics?

NASA Astrophysics Data System (ADS)

Krause, Décio; Arenhart, Jonas R. B.

2014-12-01

In this paper we argue that physical theories, including quantum mechanics, refer to some kind of `objects', even if only implicitly. We raise questions about the logico-mathematical apparatuses commonly employed in such theories, bringing to light some metaphysical presuppositions underlying such apparatuses. We point out to some incongruities in the discourse holding that quantum objects would be entities of some `new kind' while still adhering to the logico-mathematical framework we use to deal with classical objects. The use of such apparatus would hinder us from being in complete agreement with the ontological novelties the theories of quanta seem to advance. Thus, we join those who try to investigate a `logic of quantum mechanics', but from a different point of view: looking for a formal foundation for a supposed new ontology. As a consequence of this move, we can revisit Einstein's ideas on physical reality and propose that, by considering a new kind of object traditionally termed `non-individuals', it is possible to sustain that they still obey some of Einstein's conditions for `physical realities', so that it will be possible to talk of a `principle of separability' in a sense which is not in complete disagreement with quantum mechanics. So, Einstein's departure from quantum mechanics might be softened at least concerning a form of his realism, which sees separated physical objects as distinct `physical realities'.

Structure elucidation and absolute stereochemistry of isomeric monoterpene chromane esters.

PubMed

Batista, João M; Batista, Andrea N L; Mota, Jonas S; Cass, Quezia B; Kato, Massuo J; Bolzani, Vanderlan S; Freedman, Teresa B; López, Silvia N; Furlan, Maysa; Nafie, Laurence A

2011-04-15

Six novel monoterpene chromane esters were isolated from the aerial parts of Peperomia obtusifolia (Piperaceae) using chiral chromatography. This is the first time that chiral chromane esters of this kind, ones with a tethered chiral terpene, have been isolated in nature. Due to their structural features, it is not currently possible to assess directly their absolute stereochemistry using any of the standard classical approaches, such as X-ray crystallography, NMR, optical rotation, or electronic circular dichroism (ECD). Herein we report the absolute configuration of these molecules, involving four chiral centers, using vibrational circular dichroism (VCD) and density functional theory (DFT) (B3LYP/6-31G*) calculations. This work further reinforces the capability of VCD to determine unambiguously the absolute configuration of structurally complex molecules in solution, without crystallization or derivatization, and demonstrates the sensitivity of VCD to specify the absolute configuration for just one among a number of chiral centers. We also demonstrate the sufficiency of using the so-called inexpensive basis set 6-31G* compared to the triple-ζ basis set TZVP for absolute configuration analysis of larger molecules using VCD. Overall, this work extends our knowledge of secondary metabolites in plants and provides a straightforward way to determine the absolute configuration of complex natural products involving a chiral parent moiety combined with a chiral terpene adduct.

Enhancing the violation of the einstein-podolsky-rosen local realism by quantum hyperentanglement.

PubMed

Barbieri, Marco; De Martini, Francesco; Mataloni, Paolo; Vallone, Giuseppe; Cabello, Adán

2006-10-06

Mermin's observation [Phys. Rev. Lett. 65, 1838 (1990)] that the magnitude of the violation of local realism, defined as the ratio between the quantum prediction and the classical bound, can grow exponentially with the size of the system is demonstrated using two-photon hyperentangled states entangled in polarization and path degrees of freedom, and local measurements of polarization and path simultaneously.

A Proposal for Testing Local Realism Without Using Assumptions Related to Hidden Variable States

NASA Technical Reports Server (NTRS)

Ryff, Luiz Carlos

1996-01-01

A feasible experiment is discussed which allows us to prove a Bell's theorem for two particles without using an inequality. The experiment could be used to test local realism against quantum mechanics without the introduction of additional assumptions related to hidden variables states. Only assumptions based on direct experimental observation are needed.

Processing Digital Imagery to Enhance Perceptions of Realism

NASA Technical Reports Server (NTRS)

Woodell, Glenn A.; Jobson, Daniel J.; Rahman, Zia-ur

2003-01-01

Multi-scale retinex with color restoration (MSRCR) is a method of processing digital image data based on Edwin Land s retinex (retina + cortex) theory of human color vision. An outgrowth of basic scientific research and its application to NASA s remote-sensing mission, MSRCR is embodied in a general-purpose algorithm that greatly improves the perception of visual realism and the quantity and quality of perceived information in a digitized image. In addition, the MSRCR algorithm includes provisions for automatic corrections to accelerate and facilitate what could otherwise be a tedious image-editing process. The MSRCR algorithm has been, and is expected to continue to be, the basis for development of commercial image-enhancement software designed to extend and refine its capabilities for diverse applications.

Importance of Matching Physical Friction, Hardness, and Texture in Creating Realistic Haptic Virtual Surfaces.

PubMed

Culbertson, Heather; Kuchenbecker, Katherine J

2017-01-01

Interacting with physical objects through a tool elicits tactile and kinesthetic sensations that comprise your haptic impression of the object. These cues, however, are largely missing from interactions with virtual objects, yielding an unrealistic user experience. This article evaluates the realism of virtual surfaces rendered using haptic models constructed from data recorded during interactions with real surfaces. The models include three components: surface friction, tapping transients, and texture vibrations. We render the virtual surfaces on a SensAble Phantom Omni haptic interface augmented with a Tactile Labs Haptuator for vibration output. We conducted a human-subject study to assess the realism of these virtual surfaces and the importance of the three model components. Following a perceptual discrepancy paradigm, subjects compared each of 15 real surfaces to a full rendering of the same surface plus versions missing each model component. The realism improvement achieved by including friction, tapping, or texture in the rendering was found to directly relate to the intensity of the surface's property in that domain (slipperiness, hardness, or roughness). A subsequent analysis of forces and vibrations measured during interactions with virtual surfaces indicated that the Omni's inherent mechanical properties corrupted the user's haptic experience, decreasing realism of the virtual surface.

Fighting with Reality: Considering Mark Johnson's Pragmatic Realism through Bruce Lee's Jeet Kune Do Method

ERIC Educational Resources Information Center

Miller, Alexander David

2015-01-01

This dissertation considers the supportive and complementary relation between Mark Johnson's embodied realism and Bruce Lee's Jeet Kune Do as a philosophical practice. In exploring this relationship, the emphasis on one's embodiment condition and its relationship with metaphor and self-expression are the primary focus. First, this work involves…

Improving the physiological realism of experimental models

PubMed Central

Vinnakota, Kalyan C.; Cha, Chae Y.; Rorsman, Patrik; Balaban, Robert S.; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A.

2016-01-01

The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease. PMID:27051507

Controlling the stereochemistry and regularity of butanethiol self-assembled monolayers on au(111).

PubMed

Yan, Jiawei; Ouyang, Runhai; Jensen, Palle S; Ascic, Erhad; Tanner, David; Mao, Bingwei; Zhang, Jingdong; Tang, Chunguang; Hush, Noel S; Ulstrup, Jens; Reimers, Jeffrey R

2014-12-10

The rich stereochemistry of the self-assembled monolayers (SAMs) of four butanethiols on Au(111) is described, the SAMs containing up to 12 individual C, S, or Au chiral centers per surface unit cell. This is facilitated by synthesis of enantiomerically pure 2-butanethiol (the smallest unsubstituted chiral alkanethiol), followed by in situ scanning tunneling microscopy (STM) imaging combined with density functional theory molecular dynamics STM image simulations. Even though butanethiol SAMs manifest strong headgroup interactions, steric interactions are shown to dominate SAM structure and chirality. Indeed, steric interactions are shown to dictate the nature of the headgroup itself, whether it takes on the adatom-bound motif RS(•)Au(0)S(•)R or involves direct binding of RS(•) to face-centered-cubic or hexagonal-close-packed sites. Binding as RS(•) produces large, organizationally chiral domains even when R is achiral, while adatom binding leads to rectangular plane groups that suppress long-range expression of chirality. Binding as RS(•) also inhibits the pitting intrinsically associated with adatom binding, desirably producing more regularly structured SAMs.

CG2Real: Improving the Realism of Computer Generated Images Using a Large Collection of Photographs.

PubMed

Johnson, Micah K; Dale, Kevin; Avidan, Shai; Pfister, Hanspeter; Freeman, William T; Matusik, Wojciech

2011-09-01

Computer-generated (CG) images have achieved high levels of realism. This realism, however, comes at the cost of long and expensive manual modeling, and often humans can still distinguish between CG and real images. We introduce a new data-driven approach for rendering realistic imagery that uses a large collection of photographs gathered from online repositories. Given a CG image, we retrieve a small number of real images with similar global structure. We identify corresponding regions between the CG and real images using a mean-shift cosegmentation algorithm. The user can then automatically transfer color, tone, and texture from matching regions to the CG image. Our system only uses image processing operations and does not require a 3D model of the scene, making it fast and easy to integrate into digital content creation workflows. Results of a user study show that our hybrid images appear more realistic than the originals.

Faithful test of nonlocal realism with entangled coherent states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Chang-Woo; Jeong, Hyunseok; Paternostro, Mauro

2011-02-15

We investigate the violation of Leggett's inequality for nonlocal realism using entangled coherent states and various types of local measurements. We prove mathematically the relation between the violation of the Clauser-Horne-Shimony-Holt form of Bell's inequality and Leggett's one when tested by the same resources. For Leggett inequalities, we generalize the nonlocal realistic bound to systems in Hilbert spaces larger than bidimensional ones and introduce an optimization technique that allows one to achieve larger degrees of violation by adjusting the local measurement settings. Our work describes the steps that should be performed to produce a self-consistent generalization of Leggett's original argumentsmore » to continuous-variable states.« less

Conflicting Goals of Educational Action: A Study of Teacher Agency from A Transactional Realism Perspective

ERIC Educational Resources Information Center

Bergh, Andreas; Wahlström, Ninni

2018-01-01

This study focuses on the different ways in which teachers relate their situational agency and professional assignment to the national curriculum content and curriculum dilemmas. It builds theoretically on transactional realism and empirically on analyses of interviews with teachers, exploring the nature of teacher agency during the enactment of a…

The effect of stereochemistry on the biological activity of natural phytotoxins, fungicides, insecticides and herbicides.

PubMed

Evidente, Antonio; Cimmino, Alessio; Andolfi, Anna

2013-02-01

Phytotoxins are secondary microbial metabolites that play an essential role in the development of disease symptoms induced by fungi on host plants. Although phytotoxins can cause extensive-and in some cases devastating-damage to agricultural crops, they can also represent an important tool to develop natural herbicides when produced by fungi and plants to inhibit the growth and spread of weeds. An alternative strategy to biologically control parasitic plants is based on the use of plant and fungal metabolites, which stimulate seed germination in the absence of the host plant. Nontoxigenic fungi also produce bioactive metabolites with potential fungicide and insecticide activity, and could be applied for crop protection. All these metabolites represent important tools to develop eco-friendly pesticides. This review deals with the relationships between the biological activity of some phytotoxins, seed germination stimulants, fungicides and insecticides, and their stereochemistry. Copyright © 2012 Wiley Periodicals, Inc.

Comparative analysis of the heme iron electronic structure and stereochemistry in tetrameric rabbit hemoglobin and monomeric soybean leghemoglobin a using Mössbauer spectroscopy with a high velocity resolution

NASA Astrophysics Data System (ADS)

Alenkina, I. V.; Kumar, A.; Berkovsky, A. L.; Oshtrakh, M. I.

2018-02-01

A comparative study of tetrameric rabbit hemoglobin and monomeric soybean leghemoglobin a in the oxy- and deoxy-forms was carried out using 57Fe Mössbauer spectroscopy with a high velocity resolution in order to analyze the heme iron electronic structure and stereochemistry in relation to the Mössbauer hyperfine parameters. The Mössbauer spectra of tetrameric rabbit hemoglobin in both forms were fitted using two quadrupole doublets related to the 57Fe in ɑ- and β-subunits. In contrast, the Mössbauer spectra of monomeric soybean leghemoglobin a were fitted using: (i) two quadrupole doublets for the oxy-form related to two conformational states of the distal His E7 imidazole ring and different hydrogen bonding of oxygen molecule in the oxy-form and (ii) using three quadrupole doublets for deoxy-form related to three conformational states of the proximal His F8 imidazole ring. Small variations of Mössbauer hyperfine parameters related to small differences in the heme iron electronic structure and stereochemistry in tetrameric rabbit hemoglobin and monomeric soybean leghemoglobin a are discussed.

Emotions Bias Perceptions of Realism in Audiovisual Media: Why We May Take Fiction for Real

ERIC Educational Resources Information Center

Konijn, Elly A.; Walma van der Molen, Juliette H.; van Nes, Sander

2009-01-01

This study investigated whether emotions induced in TV-viewers (either as an emotional state or co-occurring with emotional involvement) would increase viewers' perception of realism in a fake documentary and affect the information value that viewers would attribute to its content. To that end, two experiments were conducted that manipulated (a)…

Differential effects of face-realism and emotion on event-related brain potentials and their implications for the uncanny valley theory

NASA Astrophysics Data System (ADS)

Schindler, Sebastian; Zell, Eduard; Botsch, Mario; Kissler, Johanna

2017-03-01

Cartoon characters are omnipresent in popular media. While few studies have scientifically investigated their processing, in computer graphics, efforts are made to increase realism. Yet, close approximations of reality have been suggested to evoke sometimes a feeling of eeriness, the “uncanny valley” effect. Here, we used high-density electroencephalography to investigate brain responses to professionally stylized happy, angry, and neutral character faces. We employed six face-stylization levels varying from abstract to realistic and investigated the N170, early posterior negativity (EPN), and late positive potential (LPP) event-related components. The face-specific N170 showed a u-shaped modulation, with stronger reactions towards both most abstract and most realistic compared to medium-stylized faces. For abstract faces, N170 was generated more occipitally than for real faces, implying stronger reliance on structural processing. Although emotional faces elicited highest amplitudes on both N170 and EPN, on the N170 realism and expression interacted. Finally, LPP increased linearly with face realism, reflecting activity increase in visual and parietal cortex for more realistic faces. Results reveal differential effects of face stylization on distinct face processing stages and suggest a perceptual basis to the uncanny valley hypothesis. They are discussed in relation to face perception, media design, and computer graphics.

MMORPG escapism predicts decreased well-being: examination of gaming time, game realism beliefs, and online social support for offline problems.

PubMed

Kaczmarek, Lukasz D; Drążkowski, Dariusz

2014-05-01

Massively multiplayer online role-playing game (MMORPG) escapists are individuals who indulge in the MMORPG environment to avoid real world problems. Though a relationship between escapism and deteriorated well-being has been established, little is known about particular pathways that mediate this relationship. In the current study, we examined this topic by testing an integrative model of MMORPG escapism, which includes game realism beliefs, gaming time, offline social support, and online social support for offline problems. MMORPG players (N=1,056) completed measures of escapist motivation, game realism beliefs, social support, well-being, and reported gaming time. The tested structural equation model had a good fit to the data. We found that individuals with escapist motivation endorsed stronger game realism beliefs and spent more time playing MMORPGs, which, in turn, increased online support but decreased offline social support. Well-being was favorably affected by both online and offline social support, although offline social support had a stronger effect. The higher availability of online social support for offline problems did not compensate for the lower availability of offline support among MMORPG escapists. Understanding the psychological factors related to depletion of social resources in MMORPG players can help optimize MMORPGs as leisure activities.

Differential effects of face-realism and emotion on event-related brain potentials and their implications for the uncanny valley theory

PubMed Central

Schindler, Sebastian; Zell, Eduard; Botsch, Mario; Kissler, Johanna

2017-01-01

Cartoon characters are omnipresent in popular media. While few studies have scientifically investigated their processing, in computer graphics, efforts are made to increase realism. Yet, close approximations of reality have been suggested to evoke sometimes a feeling of eeriness, the “uncanny valley” effect. Here, we used high-density electroencephalography to investigate brain responses to professionally stylized happy, angry, and neutral character faces. We employed six face-stylization levels varying from abstract to realistic and investigated the N170, early posterior negativity (EPN), and late positive potential (LPP) event-related components. The face-specific N170 showed a u-shaped modulation, with stronger reactions towards both most abstract and most realistic compared to medium-stylized faces. For abstract faces, N170 was generated more occipitally than for real faces, implying stronger reliance on structural processing. Although emotional faces elicited highest amplitudes on both N170 and EPN, on the N170 realism and expression interacted. Finally, LPP increased linearly with face realism, reflecting activity increase in visual and parietal cortex for more realistic faces. Results reveal differential effects of face stylization on distinct face processing stages and suggest a perceptual basis to the uncanny valley hypothesis. They are discussed in relation to face perception, media design, and computer graphics. PMID:28332557

Study of the Stereochemistry and Oxidation Mechanism of Plant Polyphenols, Assisted by Computational Chemistry.

PubMed

Matsuo, Yosuke

2017-01-01

In recent years, plant polyphenols have attracted great attention due to their wide range of biological activities. Certain kinds of polyphenols have complex structures; therefore, it is difficult to elucidate their total structure, including stereochemistry. In this study, we reinvestigated the stereostructures of two major C-glycosidic ellagitannins contained in Quercus plants, vescalagin and castalagin, and revised their stereostructures based on theoretical calculations of spectroscopic data. We also determined the structures of quercusnins A and B, isolated from the sapwood of Quercus crispula, based on theoretical calculations of NMR data. The oxidation mechanism of polyphenols has not been entirely elucidated. Therefore, we have also studied the oxidation mechanism of tea catechins during black tea production. Our investigation of the oxidation mechanism of black tea pigment theaflavins revealed that the difference in the position of the galloyl ester affords different oxidation products of theaflavins. In addition, oxidation products of pyrogallol-type catechins could be classified into three types-dehydrotheasinensins, theacitrins, and proepitheaflagallins; their detailed production and degradation mechanisms were also examined.

Realism, Instrumentalism, and Scientific Symbiosis: Psychological Theory as a Search for Truth and the Discovery of Solutions

ERIC Educational Resources Information Center

Cacioppo, John T.; Semin, Gun R.; Berntson, Gary G.

2004-01-01

Scientific realism holds that scientific theories are approximations of universal truths about reality, whereas scientific instrumentalism posits that scientific theories are intellectual structures that provide adequate predictions of what is observed and useful frameworks for answering questions and solving problems in a given domain. These…

The Metaphysics of Morris R. Cohen: From Realism to Objective Relativism.

PubMed

Cahoone, Lawrence

2017-01-01

Morris Cohen is mainly remembered as a philosopher of history and law, a friend of jurists (Oliver Wendell Holmes, Felix Frankfurter), and a teacher of more prominent philosophers (e.g., Ernest Nagel, Paul Weiss, Morton White). But his unique position as a student of the work of Russell and Peirce led him to make a distinctive contribution to the debate over realism in in the 1910s. Largely ignored and completely uncited, his early papers formulated what would later be called "objective relativism," influencing the later work of Columbia naturalism, hence American philosophy, from the 1940s to the 1960s.

Improving the realism of hydrologic model through multivariate parameter estimation

NASA Astrophysics Data System (ADS)

Rakovec, Oldrich; Kumar, Rohini; Attinger, Sabine; Samaniego, Luis

2017-04-01

Increased availability and quality of near real-time observations should improve understanding of predictive skills of hydrological models. Recent studies have shown the limited capability of river discharge data alone to adequately constrain different components of distributed model parameterizations. In this study, the GRACE satellite-based total water storage (TWS) anomaly is used to complement the discharge data with an aim to improve the fidelity of mesoscale hydrologic model (mHM) through multivariate parameter estimation. The study is conducted in 83 European basins covering a wide range of hydro-climatic regimes. The model parameterization complemented with the TWS anomalies leads to statistically significant improvements in (1) discharge simulations during low-flow period, and (2) evapotranspiration estimates which are evaluated against independent (FLUXNET) data. Overall, there is no significant deterioration in model performance for the discharge simulations when complemented by information from the TWS anomalies. However, considerable changes in the partitioning of precipitation into runoff components are noticed by in-/exclusion of TWS during the parameter estimation. A cross-validation test carried out to assess the transferability and robustness of the calibrated parameters to other locations further confirms the benefit of complementary TWS data. In particular, the evapotranspiration estimates show more robust performance when TWS data are incorporated during the parameter estimation, in comparison with the benchmark model constrained against discharge only. This study highlights the value for incorporating multiple data sources during parameter estimation to improve the overall realism of hydrologic model and its applications over large domains. Rakovec, O., Kumar, R., Attinger, S. and Samaniego, L. (2016): Improving the realism of hydrologic model functioning through multivariate parameter estimation. Water Resour. Res., 52, http://dx.doi.org/10

Impact of Dysphoria and Self-Consciousness on Perceptions of Social Competence: Test of the Depressive Realism Hypothesis

ERIC Educational Resources Information Center

Chau, Phuong M.; Milling, Leonard S.

2006-01-01

Depressive realism refers to a cognitive style wherein depressed people sometimes have more accurate perceptions of reality than nondepressed people. The notion of depressives being "sadder yet wiser" was controversial when first presented, and continues to be heavily debated. Self-perception studies provide maximum external validity,…

Mechanism and stereochemistry for nucleophilic attack at carbon of platinum (iv) alkyls: Model reactions for hydrocarbon oxidation with aqueous platinum chlorides. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luinstra, G.A.; Labinger, J.A.; Bercaw, J.E.

1992-10-01

Reactions of PtCl4(2-) with RI (R = CH3, CH2CH2OH) in water yield PtCl5R(2-) which were isolated as their NMe4 salts. They decompose in aqueous chloride solution to give ROH and RCL. erythro- and threo-PtCl5(CHDCHDOH)(2-) are obtained by oxidation of PtCl3(cis- and trans CHD=CHD)(-) respectively. Kinetic rate laws and stereochemistry support SN2 displacement by Cl(-) or H[sub 2]O as the mechanism of the decomposition reactions.

Design of interactive health drama built on social realism.

PubMed

Graspemo, Gabriella; Hassling, Linda; Nordfeldt, Sam; Eriksson, Hendrik; Timpka, Toomas

2004-01-01

There are many psychosocial aspects of chronic diseases, such as diabetes. Educational multimedia can support patients with chronic diseases and their families by communicating narratives based on social realism. The production of such socio-realistic interactive health dramas requires systematic methods, especially for the identification of significant stories. The aim of this study is to explore the use of self-documentary video in the design of an Interactive Health Drama environment to support diabetic adolescents and their families. In particular, the potential of the self-documentary video for story development in combination with qualitative interviews were explored. The proposed approach, when further developed, is intended to enable all types of chronic disease patients to work with their specific psychosocial problems in a supportive and stimulating environment adapted to their personality and preferences.

Differentiation of the Stereochemistry and Anomeric Configuration for 1-3 Linked Disaccharides Via Tandem Mass Spectrometry and 18O-labeling

NASA Astrophysics Data System (ADS)

Konda, Chiharu; Bendiak, Brad; Xia, Yu

2012-02-01

Collision-induced dissociation (CID) of deprotonated hexose-containing disaccharides ( m/z 341) with 1-2, 1-4, and 1-6 linkages yields product ions at m/z 221, which have been identified as glycosyl-glycolaldehyde anions. From disaccharides with these linkages, CID of m/z 221 ions produces distinct fragmentation patterns that enable the stereochemistries and anomeric configurations of the non-reducing sugar units to be determined. However, only trace quantities of m/z 221 ions can be generated for 1-3 linkages in Paul or linear ion traps, preventing further CID analysis. Here we demonstrate that high intensities of m/z 221 ions can be built up in the linear ion trap (Q3) from beam-type CID of a series of 1-3 linked disaccharides conducted on a triple quadrupole/linear ion trap mass spectrometer. 18O-labeling at the carbonyl position of the reducing sugar allowed mass-discrimination of the "sidedness" of dissociation events to either side of the glycosidic linkage. Under relatively low energy beam-type CID and ion trap CID, an m/z 223 product ion containing 18O predominated. It was a structural isomer that fragmented quite differently than the glycosyl-glycolaldehydes and did not provide structural information about the non-reducing sugar. Under higher collision energy beam-type CID conditions, the formation of m/z 221 ions, which have the glycosyl-glycolaldehyde structures, were favored. Characteristic fragmentation patterns were observed for each m/z 221 ion from higher energy beam-type CID of 1-3 linked disaccharides and the stereochemistry of the non-reducing sugar, together with the anomeric configuration, were successfully identified both with and without 18O-labeling of the reducing sugar carbonyl group.

Stereoselective Synthesis of 8,12-Furanoeudesmanes from Santonin. Absolute Stereochemistry of Natural Furanoeudesma-1,3-diene and Tubipofurane.

PubMed

Blay, Gonzalo; Cardona, Luz; García, Begoña; Pedro, José R.; Sánchez, Juan J.

1996-05-31

Ketobutenolide 3, easily obtained from santonin (1), has been transformed into two natural furanoeudesmanes 4 and 5, isolated from Commiphora molmol and Tubipora musica, respectively. trans- And cis-decalin systems were obtained by stereoselective reduction of the C(4)-C(5) double bond in 3 in the following way: hydrogenation of 3 over Pd/C followed by acidic treatment gave the cis isomer 10 as the major product; selective hydrogenation of the C(1)-C(2) double bond with the Wilkinson's catalyst followed by reduction with NaTeH yielded mainly the trans isomer 9. Compounds 9 and 10 were transformed into 4 and 5 in parallel sequences. Optical rotation and CD measurements of the synthetic products revealed that the stereochemistry of both natural products should be revised to their enantiomeric form.

The Effectiveness of Physical Models in Teaching Anatomy: A Meta-Analysis of Comparative Studies

ERIC Educational Resources Information Center

Yammine, Kaissar; Violato, Claudio

2016-01-01

There are various educational methods used in anatomy teaching. While three dimensional (3D) visualization technologies are gaining ground due to their ever-increasing realism, reports investigating physical models as a low-cost 3D traditional method are still the subject of considerable interest. The aim of this meta-analysis is to quantitatively…

Depressive Realism and Outcome Density Bias in Contingency Judgments: The Effect of the Context and Intertrial Interval

ERIC Educational Resources Information Center

Msetfi, Rachel M.; Murphy, Robin A.; Simpson, Jane; Kornbrot, Diana E.

2005-01-01

The perception of the effectiveness of instrumental actions is influenced by depressed mood. Depressive realism (DR) is the claim that depressed people are particularly accurate in evaluating instrumentality. In two experiments, the authors tested the DR hypothesis using an action-outcome contingency judgment task. DR effects were a function of…

Effect of Stereochemistry on Directed Self-Assembly of Poly(styrene-b-lactide) Films on Chemical Patterns

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xiao; Liu, Yadong; Wan, Lei

2016-03-15

We demonstrated here for the first time that the stereochemistry of polylactide (PLA) blocks affected the assembly behaviors of PS-b-PLA on chemical patterns. Two PS-b-PLA block copolymers, where the PLA block is either racemic (PDLLA) or left-handed (PLLA), were synthesized and directed to assemble on chemical patterns with a wide range of L-s/L-o. PS-b-PDLLA was stretched up to 70% on chemical patterns, while PS-b-PLLA was only stretched by 20%. The assembly behavior of PS-b-PDLLA was different from AB diblock copolymer, but similar to that of ABA triblock copolymer. The high stretchability might be attributed to the formation of stereocomplexes inmore » PDLLA blocks. Compared to ABA triblock copolymers, stereocomplexed diblock copolymers have much faster assembly kinetics. This observation provides a new concept to achieve large process windows by the introduction of specific interactions, for example, H-bonding, supramolecular interaction, and sterecomplexation, between polymer chains.« less

Relativity, entanglement and the physical reality of the photon

NASA Astrophysics Data System (ADS)

Tiwari, S. C.

2002-04-01

Recent experiments on the classic Einstein-Podolsky-Rosen (EPR) setting claim to test the compatibility between nonlocal quantum entanglement and the (special) theory of relativity. Confirmation of quantum theory has led to the interpretation that Einstein's image of physical reality for each photon in the EPR pair cannot be maintained. A detailed critique on two representative experiments is presented following the original EPR notion of local realism. It is argued that relativity does not enter into the picture, however for the Bell-Bohm version of local realism in terms of hidden variables such experiments are significant. Of the two alternatives, namely incompleteness of quantum theory for describing an individual quantum system, and the ensemble view, it is only the former that has been ruled out by the experiments. An alternative approach gives a statistical ensemble interpretation of the observed data, and the significant conclusion that these experiments do not deny physical reality of the photon is obtained. After discussing the need for a photon model, a vortex structure is proposed based on the space-time invariant property-spin, and pure gauge fields. To test the prime role of spin for photons and the angular-momentum interpretation of electromagnetic fields, experimental schemes feasible in modern laboratories are suggested.

Fast, metadynamics-based method for prediction of the stereochemistry-dependent relative free energies of ligand-receptor interactions.

PubMed

Plazinska, Anita; Plazinski, Wojciech; Jozwiak, Krzysztof

2014-04-30

The computational approach applicable for the molecular dynamics (MD)-based techniques is proposed to predict the ligand-protein binding affinities dependent on the ligand stereochemistry. All possible stereoconfigurations are expressed in terms of one set of force-field parameters [stereoconfiguration-independent potential (SIP)], which allows for calculating all relative free energies by only single simulation. SIP can be used for studying diverse, stereoconfiguration-dependent phenomena by means of various computational techniques of enhanced sampling. The method has been successfully tested on the β2-adrenergic receptor (β2-AR) binding the four fenoterol stereoisomers by both metadynamics simulations and replica-exchange MD. Both the methods gave very similar results, fully confirming the presence of stereoselective effects in the fenoterol-β2-AR interactions. However, the metadynamics-based approach offered much better efficiency of sampling which allows for significant reduction of the unphysical region in SIP. Copyright © 2014 Wiley Periodicals, Inc.

Beyond Gisin’s Theorem and its Applications: Violation of Local Realism by Two-Party Einstein-Podolsky-Rosen Steering

PubMed Central

Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Yu-Chun; Wu, Chunfeng; Ye, Xiang-Jun; Żukowski, Marek; Kwek, L. C.

2015-01-01

We demonstrate here that for a given mixed multi-qubit state if there are at least two observers for whom mutual Einstein-Podolsky-Rosen steering is possible, i.e. each observer is able to steer the other qubits into two different pure states by spontaneous collapses due to von Neumann type measurements on his/her qubit, then nonexistence of local realistic models is fully equivalent to quantum entanglement (this is not so without this condition). This result leads to an enhanced version of Gisin’s theorem (originally: all pure entangled states violate local realism). Local realism is violated by all mixed states with the above steering property. The new class of states allows one e.g. to perform three party secret sharing with just pairs of entangled qubits, instead of three qubit entanglements (which are currently available with low fidelity). This significantly increases the feasibility of having high performance versions of such protocols. Finally, we discuss some possible applications. PMID:26108704

Increasing combat realism: the effectiveness of stun belt use on soldiers for the enhancement of live training and testing exercises

NASA Astrophysics Data System (ADS)

Schricker, Bradley C.; Antalek, Christopher

2006-05-01

The ability to make correct decisions while operating in a combat zone enables American and Coalition warfighters to better respond to any threats they may encounter due to the minimization of negative training the warfighter encountered during their live, virtual, and constructive (LVC) training exercises. By increasing the physical effects encountered by one's senses during combat scenarios, combat realism is able to be increased, which is a key component in the reduction in negative training. The use of LVC simulations for training and testing augmentation purposes depends on a number of factors, not the least of which is the accurate representation of the training environment. This is particularly true in the realm of tactical engagement training through the use of Tactical Engagement Simulation Systems (TESS). The training environment is perceived through human senses, most notably sight and hearing. As with other haptic devices, the sense of touch is gaining traction as a viable medium through which to express the effects of combat battle damage from the synthetic training environment to participants within a simulated training exercise. New developments in this field are promoting the safe use of an electronic stun device to indicate to a trainee that they have been hit by a projectile, from either direct or indirect fire, through the course of simulated combat. A growing number of examples suggest that this added output medium can greatly enhance the realism of a training exercise and, thus, improve the training value. This paper serves as a literature survey of this concept, beginning with an explanation of TESS. It will then focus on how the electronic stun effect may be employed within a TESS and then detail some of the noted pros and cons of such an approach. The paper will conclude with a description of potential directions and work.

Working with Cultural-Historical Activity Theory and Critical Realism to Investigate and Expand Farmer Learning in Southern Africa

ERIC Educational Resources Information Center

Mukute, Mutizwa; Lotz-Sisitka, Heila

2012-01-01

This article uses the theoretical and methodological tools of cultural historical activity theory and critical realism to examine three case studies of the introduction and expansion of sustainable agricultural practices in southern Africa. The article addresses relevant issues in the field of agricultural extension, which lacks a theoretical…

Reality and the Physicist

NASA Astrophysics Data System (ADS)

D'Espagnat, Bernard; Whitehouse, Translated by J. C.

1989-03-01

Preface; Introduction; Part I. Instrumentalism and Science: 1. The positivism of the physicists; 2. Positivism and fallibilism: philosophical controversies; 3. Border areas of instrumentalism; Part II. Physical Realism and Contemporary Physics: 4. Physical realism and fallibilism; 5. Microrealism and non-separability; 6. Physical realism in trouble; Part III. Causality, Reality and Time: 7. Irreversibility; 8. Sensible reality; 9. Independent reality; 10. The dilemma of modern physics: reality or meaning?; 11. Questions and answers; 12. Summary and perspectives; Appendixes; Addendum; Notes; References; Index.

Questioning the Value of Realism: Young Adults' Processing of Messages in Alcohol-Related Public Service Announcements and Advertising.

ERIC Educational Resources Information Center

Andsager, Julie L.; Austin, Erica Weintraub; Pinkleton, Bruce E.

2001-01-01

Finds that: (1) perceived realism and themes that students could identify with are important factors in increasing the salience and persuasiveness of alcohol-related public service announcements (PSAs) among undergraduate students; (2) realistic but logic-based PSAs were not as effective as unrealistic but enjoyable ads; and (3) low production…

Overcoming the barrier of narrative adherence in conflicts through awareness of the psychological bias of naïve realism.

PubMed

Nasie, Meytal; Bar-Tal, Daniel; Pliskin, Ruthie; Nahhas, Eman; Halperin, Eran

2014-11-01

One significant socio-psychological barrier for peaceful resolution of conflicts is each party's adherence to its own collective narrative. We hypothesized that raising awareness to the psychological bias of naïve realism and its identification in oneself would provide a path to overcoming this barrier, thus increasing openness to the adversary's narrative. We conducted three experimental studies in the context of the Israeli-Palestinian conflict. Studies 1 and 2, conducted among Jewish Israelis and Palestinian Israelis, respectively, revealed that participants with hawkish political ideology reported greater openness to the adversary's narrative when they were made aware of naïve realism bias. Study 3 revealed that hawkish participants at the baseline adhered to the ingroup narrative and resisted the adversary's narrative more than dovish participants. They were also more able to identify the bias in themselves upon learning about it. This identification may explain why the manipulation led to bias correction only among hawkish participants. © 2014 by the Society for Personality and Social Psychology, Inc.

Critical realism: a practical ontology to explain the complexities of smoking and tobacco control in different resource settings

PubMed Central

Oladele, Dunsi; Clark, Alexander M.; Richter, Solina; Laing, Lory

2013-01-01

Background This paper presents critical realism (CR) as an innovative system for research in tobacco prevention and control. CR argues that underlying mechanisms are considered and explored to ensure effective implementation of any program/policy or intervention. Any intervention or program/policy that is transposed from one country to another or one setting to another is complex. Methods The research was undertaken and analyzed through a critical ethnography lens using CR as a philosophical underpinning. The study relied upon the following components: original fieldwork in Nigeria including participant observation of smokers, in-depth interviews and focus groups with smokers, and in-depth interviews with health professionals working in the area of tobacco control in Nigeria. Results Findings from this small ethnographic study in Nigeria, suggest that Critical Realism holds promise for addressing underlying mechanism that links complex influences on smoking. Conclusion This paper argues that understanding the underlying mechanisms associated with smoking in different societies will enable a platform for effective implementation of tobacco control policies that work in various settings. PMID:23561029

Classroom Enters the Courtroom: Stereochemistry of SN1 and SN2 Reactions in Enantiomer Patent Litigations of the Antidepressant Escitalopram.

PubMed

Michman, Elisheva; Agranat, Israel

2016-01-01

The role of elementary stereochemistry is illustrated in the patent litigations of the blockbuster antidepressant drug escitalopram oxalate. An undergraduate student of organic chemistry would recognize the stereochemical courses of the intramolecular SN 2 and SN 1 reactions of the single-enantiomer (S)-diol intermediate in the synthesis of the blockbuster antidepressant drug escitalopram oxalate: retention of configuration of the chiral carbon atom under basic conditions and racemization under acidic conditions, respectively. He/she, in searching for a stereoselective ring-closure reaction of the enantiomeric diol, will think of an SN 2 reaction in a basic medium. From these points of view, the process claim in the enantiomer patents of escitalopram is obvious/lacks an inventive step. An organic chemistry examination problem based on this scenario is offered. © 2015 Wiley Periodicals, Inc.

Chameleon Effect, the Range of Values Hypothesis and Reproducing the EPR-Bohm Correlations

NASA Astrophysics Data System (ADS)

Accardi, Luigi; Khrennikov, Andrei

2007-02-01

We present a detailed analysis of assumptions that J. Bell used to show that local realism contradicts QM. We find that Bell's viewpoint on realism is nonphysical, because it implicitly assume that observed physical variables coincides with ontic variables (i.e., these variables before measurement). The real physical process of measurement is a process of dynamical interaction between a system and a measurement device. Therefore one should check the adequacy of QM not to "Bell's realism," but to adaptive realism (chameleon realism). Dropping Bell's assumption we are able to construct a natural representation of the EPR-Bohm correlations in the local (adaptive) realistic approach.

Advancing renal education: hybrid simulation, using simulated patients to enhance realism in haemodialysis education.

PubMed

Dunbar-Reid, Kylie; Sinclair, Peter M; Hudson, Denis

2015-06-01

Simulation is a well-established and proven teaching method, yet its use in renal education is not widely reported. Criticisms of simulation-based teaching include limited realism and a lack of authentic patient interaction. This paper discusses the benefits and challenges of high-fidelity simulation and suggests hybrid simulation as a complementary model to existing simulation programmes. Through the use of a simulated patient, hybrid simulation can improve the authenticity of renal simulation-based education while simultaneously teaching and assessing technologically enframed caring. © 2015 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Prediction of Stereochemistry using Q2MM

PubMed Central

2016-01-01

screens on a range of transition metal-catalyzed reactions that are important from both an industrial and an academic perspective. In this Account, we provide an overview of the continued improvement of the prediction of stereochemistry using Q2MM-derived TSFFs using four examples from different stages of development: (i) Pd-catalyzed allylation, (ii) OsO4-catalyzed asymmetric dihydroxylation (AD) of alkenes, (iii) Rh-catalyzed hydrogenation of enamides, and (iv) Ru-catalyzed hydrogenation of ketones. In the current form, correlation coefficients of 0.8–0.9 between calculated and experimental ee values are typical for a wide range of substrate–ligand combinations, and suitable ligands can be predicted for a given substrate with ∼80% accuracy. Although the generation of a TSFF requires an initial effort and will therefore be most useful for widely used reactions that require frequent screening campaigns, the method allows for a rapid virtual screen of large ligand libraries to focus experimental efforts on the most promising substrate–ligand combinations. PMID:27064579

Actuality of transcendental æsthetics for modern physics

NASA Astrophysics Data System (ADS)

Petitot, Jean

1. The more mathematics and physics unify themselves in the physico-mathematical modern theories, the more an objective epistemology becomes necessary. Only such a transcendental epistemology is able to thematize correctly the status of the mathematical determination of physical reality. 2. There exists a transcendental history of the synthetic a priori and of the construction of physical categories. 3. The transcendental approach allows to supersed Wittgenstein's and Carnap's antiplatonist thesis according to which pure mathematics are physically applicable only if they lack any descriptive, cognitive or objective, content and reduce to mere prescriptive and normative devices. In fact, pure mathematics are prescriptive-normative in physics because: (i) the categories of physical objectivity are prescriptive-normative, and (ii) their categorial content is mathematically “constructed” through a Transcendental Aesthetics. Only a transcendental approach make compatible, in the one hand, a grammatical conventionalism of Wittgensteinian or Carnapian type and, on the other hand, a platonist realism of Gödelian type. Mathematics are not a grammar of the world but a mathematical hermeneutics of the intuitive forms and of the categorial grammar of the world.

Emergence of realism: Enhanced visual artistry and high accuracy of visual numerosity representation after left prefrontal damage.

PubMed

Takahata, Keisuke; Saito, Fumie; Muramatsu, Taro; Yamada, Makiko; Shirahase, Joichiro; Tabuchi, Hajime; Suhara, Tetsuya; Mimura, Masaru; Kato, Motoichiro

2014-05-01

Over the last two decades, evidence of enhancement of drawing and painting skills due to focal prefrontal damage has accumulated. It is of special interest that most artworks created by such patients were highly realistic ones, but the mechanism underlying this phenomenon remains to be understood. Our hypothesis is that enhanced tendency of realism was associated with accuracy of visual numerosity representation, which has been shown to be mediated predominantly by right parietal functions. Here, we report a case of left prefrontal stroke, where the patient showed enhancement of artistic skills of realistic painting after the onset of brain damage. We investigated cognitive, functional and esthetic characteristics of the patient׳s visual artistry and visual numerosity representation. Neuropsychological tests revealed impaired executive function after the stroke. Despite that, the patient׳s visual artistry related to realism was rather promoted across the onset of brain damage as demonstrated by blind evaluation of the paintings by professional art reviewers. On visual numerical cognition tasks, the patient showed higher performance in comparison with age-matched healthy controls. These results paralleled increased perfusion in the right parietal cortex including the precuneus and intraparietal sulcus. Our data provide new insight into mechanisms underlying change in artistic style due to focal prefrontal lesion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Educational program in crisis management for cardiac surgery teams including high realism simulation.

PubMed

Stevens, Louis-Mathieu; Cooper, Jeffrey B; Raemer, Daniel B; Schneider, Robert C; Frankel, Allan S; Berry, William R; Agnihotri, Arvind K

2012-07-01

Cardiac surgery demands effective teamwork for safe, high-quality care. The objective of this pilot study was to develop a comprehensive program to sharpen performance of experienced cardiac surgical teams in acute crisis management. We developed and implemented an educational program for cardiac surgery based on high realism acute crisis simulation scenarios and interactive whole-unit workshop. The impact of these interventions was assessed with postintervention questionnaires, preintervention and 6-month postintervention surveys, and structured interviews. The realism of the acute crisis simulation scenarios gradually improved; most participants rated both the simulation and whole-unit workshop as very good or excellent. Repeat simulation training was recommended every 6 to 12 months by 82% of the participants. Participants of the interactive workshop identified 2 areas of highest priority: encouraging speaking up about critical information and interprofessional information sharing. They also stressed the importance of briefings, early communication of surgical plan, knowing members of the team, and continued simulation for practice. The pre/post survey response rates were 70% (55/79) and 66% (52/79), respectively. The concept of working as a team improved between surveys (P = .028), with a trend for improvement in gaining common understanding of the plan before a procedure (P = .075) and appropriate resolution of disagreements (P = .092). Interviewees reported that the training had a positive effect on their personal behaviors and patient care, including speaking up more readily and communicating more clearly. Comprehensive team training using simulation and a whole-unit interactive workshop can be successfully deployed for experienced cardiac surgery teams with demonstrable benefits in participant's perception of team performance. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Can Virtual Reality Increase the Realism of Role Plays Used to Teach College Women Sexual Coercion and Rape-Resistance Skills?

ERIC Educational Resources Information Center

Jouriles, Ernest N.; McDonald, Renee; Kullowatz, Antje; Rosenfield, David; Gomez, Gabriella S.; Cuevas, Anthony

2009-01-01

The present study evaluated whether virtual reality (VR) can enhance the realism of role plays designed to help college women resist sexual attacks. Sixty-two female undergraduate students were randomly assigned to either the Role Play (RP) or Virtual Role Play (VRP) conditions, which were differentiated only by the use of VR technology in the VRP…

The (old) New Realism: what Holt has to offer for ecological psychology.

PubMed

Charles, Eric P

2009-03-01

As Ecological Psychology pushes into new areas, success will be made easier by a rediscovery its theoretical history, in particular the "New Realism", lead in part by E. B. Holt. Three New Realists tenants seem particularly relevant: (1) we experience reality, (2) relations are real, and (3) things are what you see when you see those things. Though the two groups differ in terms of their conception of perception, and what can be perceived, their conceptions are related in very insightful ways. Further, the comparison reemphasizes the extent of unique empirical claims ecological psychologists make, and grounds those claims within a larger framework for psychology as a whole. This makes obvious the need for further work on the mathematics of invariants, the physiological mechanisms of information extraction, and the behaviors of perception.

Using the PhysX engine for physics-based virtual surgery with force feedback.

PubMed

Maciel, Anderson; Halic, Tansel; Lu, Zhonghua; Nedel, Luciana P; De, Suvranu

2009-09-01

The development of modern surgical simulators is highly challenging, as they must support complex simulation environments. The demand for higher realism in such simulators has driven researchers to adopt physics-based models, which are computationally very demanding. This poses a major problem, since real-time interactions must permit graphical updates of 30 Hz and a much higher rate of 1 kHz for force feedback (haptics). Recently several physics engines have been developed which offer multi-physics simulation capabilities, including rigid and deformable bodies, cloth and fluids. While such physics engines provide unique opportunities for the development of surgical simulators, their higher latencies, compared to what is necessary for real-time graphics and haptics, offer significant barriers to their use in interactive simulation environments. In this work, we propose solutions to this problem and demonstrate how a multimodal surgical simulation environment may be developed based on NVIDIA's PhysX physics library. Hence, models that are undergoing relatively low-frequency updates in PhysX can exist in an environment that demands much higher frequency updates for haptics. We use a collision handling layer to interface between the physical response provided by PhysX and the haptic rendering device to provide both real-time tissue response and force feedback. Our simulator integrates a bimanual haptic interface for force feedback and per-pixel shaders for graphics realism in real time. To demonstrate the effectiveness of our approach, we present the simulation of the laparoscopic adjustable gastric banding (LAGB) procedure as a case study. To develop complex and realistic surgical trainers with realistic organ geometries and tissue properties demands stable physics-based deformation methods, which are not always compatible with the interaction level required for such trainers. We have shown that combining different modelling strategies for behaviour, collision and

Synthesis, stereochemistry determination, pharmacological studies and quantum chemical analyses of bisthiazolidinone derivative

NASA Astrophysics Data System (ADS)

Mushtaque, Md.; Avecilla, Fernando; Hafeez, Zubair Bin; Jahan, Meriyam; Khan, Md. Shahzad; Rizvi, M. Moshahid A.; Khan, Mohd. Shahid; Srivastava, Anurag; Mallik, Anwesha; Verma, Saurabh

2017-01-01

A new compound (3) bisthaizolidinone derivative was synthesized by Knoevenagel condensation reaction. The structure of synthesized compound was elucidated by different spectral techniques and X-ray diffraction studies. The stereochemistry of the compound (3) was determined by 1Hsbnd 1H NOESY, 1Hsbnd 1H NMR COSY and single crystal X-ray diffraction studies as (Z, Z)-configuration. The computational quantum chemical studies of compound(3) like, IR, UV, NBO analysis were performed by DFT with Becke-3-Lee-Yang-Parr (B3LYP) exchange-correlation functional in combination with 6-311++G(d,p) basis sets. The DNA-binding of compound (3) exhibited a moderate binding constant (Kb = 1 × 105 Lmol-1) with hypochromic shift. The molecular docking displayed good binding affinity -7.18 kcal/mol. The MTT assay of compound (3) was screened against different cancerous cell lines, HepG2, Siha, Hela and MCF-7. Studies against these cell lines depicted that the screened compound (3) showed potent inhibitory activity against HepG2 cell (IC50 = 7.5 μM) followed by MCF-7 (IC50 = 52.0 μM), Siha (IC50 = 66.98 μM), Hela (IC50 = 74.83 μM) cell lines, and non-toxic effect against non-cancerous HEK-293 cells (IC50 = 287.89 μM) at the concentration range (0-300) μM. Furthermore, cell cycle perturbation was performed on HepG2 & Siha cell lines and observed that cells were arrested in G2/M in HepG2, and G0/G1 in Siha cell lines with respect to untreated control. Hence, compound (3) possesses potent anti-cancerous activity against HepG2 cell line.

Future Orientation among Caucasian and Arab-American Adolescents: The Role of Realism About Child-Rearing and Perceptions of Others' Acceptance of Adolescent Pregnancy

ERIC Educational Resources Information Center

Mirza, Saima A.; Somers, Cheryl L.

2004-01-01

Future orientation in adolescents is an important concept to study because of its relations with academic performance and success levels. This study examined adolescents' realism about childrearing and their perceptions of others' approval of teen pregnancy to examine their association with future orientation. Participants were 476 high…

Perceived realism moderates the relation between sexualized media consumption and permissive sexual attitudes in Dutch adolescents.

PubMed

Baams, Laura; Overbeek, Geertjan; Dubas, Judith Semon; Doornwaard, Suzan M; Rommes, Els; van Aken, Marcel A G

2015-04-01

This study examined whether the development of sexualized media consumption and permissive sexual attitudes would be more strongly interrelated when adolescents perceived sexualized media images as highly realistic. We used data from a three-wave longitudinal sample of 444 Dutch adolescents aged 13-16 years at baseline. Results from parallel process latent growth modeling multigroup analyses showed that higher initial levels of sexualized media consumption were associated with higher initial level of permissive sexual attitudes. Moreover, increases of sexualized media consumption over time were associated with increases of permissive sexual attitudes over time. Considering the moderation by perceived realism, we found these effects only for those who perceived sexualized media as more realistic. Findings for male and female adolescents were similar except for the relations between initial levels and subsequent development. Among male adolescents who perceived sexualized media images to be realistic, higher initial levels of permissive sexual attitudes were related to subsequent less rapid development of sexualized media consumption. For male adolescents who perceived sexualized media to be less realistic, higher initial levels of sexualized media consumption were related to a subsequent less rapid development of permissive sexual attitudes. These relations were not found for female adolescents. Overall, our results suggest that, in male and female adolescents, those with a high level of perceived realism showed a correlated development of sexualized media consumption and permissive sexual attitudes. These findings point to a need for extended information on how to guide adolescents in interpreting and handling sexualized media in everyday life.

Images of Inherited War: Three American Presidents in Vietnam

DTIC Science & Technology

2011-06-01

Dependent Realism to demonstrate how theoretical advances in modern physical science correlate to cognitive theories in International Relations. We...Quantum Physics and Model-Dependent Realism In his book, The Grand Design, theoretical physicist and cosmologist Stephen Hawking draws on theoretical...exhibited wave-like properties and that existing scientific laws could not account for their behavior. Newtonian physics was “built on a framework

Z-sinapinic acid: the change of the stereochemistry of cinnamic acids as rational synthesis of a new matrix for carbohydrate MALDI-MS analysis.

PubMed

Salum, María L; Itovich, Lucia M; Erra-Balsells, Rosa

2013-11-01

Successful application of matrix-assisted laser desorption/ionization (MALDI) MS started with the introduction of efficient matrices such as cinnamic acid derivatives (i.e. 3,5-dimethoxy-4-hydroxycinnamic acid, SA; α-cyano-4-hydroxycinnamic acid). Since the empirical founding of these matrices, other commercial available cinnamic acids with different nature and location of substituents at benzene ring were attempted. Rational design and synthesis of new cinnamic acids have been recently described too. Because the presence of a rigid double bond in its molecule structure, cinnamic acids can exist as two different geometric isomers, the E-form and Z-form. Commercial available cinnamic acids currently used as matrices are the geometric isomers trans or E (E-cinnamic and trans-cinnamic acids). As a new rational design of MALDI matrices, Z-cinnamic acids were synthesized, and their properties as matrices were studied. Their performance was compared with that of the corresponding E-isomer and classical crystalline matrices (3,5-dihydroxybenzoic acid; norharmane) in the analysis of neutral/sulfated carbohydrates. Herein, we demonstrate the outstanding performance for Z-SA. Sulfated oligosaccharides were detected in negative ion mode, and the dissociation of sulfate groups was almost suppressed. Additionally, to better understand the quite different performance of each geometric isomer as matrix, the physical and morphological properties as well as the photochemical stability in solid state were studied. The influence of the E/Z photoisomerization of the matrix during MALDI was evaluated. Finally, molecular modeling (density functional theory study) of the optimized geometry and stereochemistry of E-cinnamic and Z-cinnamic acids revealed some factors governing the analyte-matrix interaction. Copyright © 2013 John Wiley & Sons, Ltd.

Rabies elimination research: juxtaposing optimism, pragmatism and realism

PubMed Central

Hampson, Katie

2017-01-01

More than 100 years of research has now been conducted into the prevention, control and elimination of rabies with safe and highly efficacious vaccines developed for use in human and animal populations. Domestic dogs are a major reservoir for rabies, and although considerable advances have been made towards the elimination and control of canine rabies in many parts of the world, the disease continues to kill tens of thousands of people every year in Africa and Asia. Policy efforts are now being directed towards a global target of zero human deaths from dog-mediated rabies by 2030 and the global elimination of canine rabies. Here we demonstrate how research provides a cause for optimism as to the feasibility of these goals through strategies based around mass dog vaccination. We summarize some of the pragmatic insights generated from rabies epidemiology and dog ecology research that can improve the design of dog vaccination strategies in low- and middle-income countries and which should encourage implementation without further delay. We also highlight the need for realism in reaching the feasible, although technically more difficult and longer-term goal of global elimination of canine rabies. Finally, we discuss how research on rabies has broader relevance to the control and elimination of a suite of diseases of current concern to human and animal health, providing an exemplar of the value of a ‘One Health’ approach. PMID:29263285

Televised entertainment-education to prevent adolescent alcohol use: perceived realism, enjoyment, and impact.

PubMed

van Leeuwen, Lonneke; Renes, Reint Jan; Leeuwis, Cees

2013-04-01

Alcohol use among adolescents is a concern in the Netherlands because of its high prevalence and risks. To discourage adolescents from drinking alcohol, a televised entertainment-education (E-E) intervention was developed. This study investigated responses of adolescents on perceived realism and enjoyment of the E-E intervention, as well as its impact on alcohol drinking behavior. Viewers perceived the E-E narratives to be credible and enjoyable but did not relate to the characters in the narratives. However, exposure to the E-E intervention predicted desired changes in alcohol drinking behavior, intentions to decrease alcohol use, and perceived normative pressure, especially in less educated viewers. These findings demonstrate that E-E is a promising strategy to target adolescent alcohol use. Future research will focus on the individual processes and story elements that account for the positive results.

From minerals to hillslopes: Towards an integrated framework for interpreting chemical and physical erosion

NASA Astrophysics Data System (ADS)

Hahm, W.; Riebe, C. S.; Ferrier, K.; Kirchner, J. W.

2011-12-01

Traditional frameworks for conceptualizing hillslope denudation distinguish between the movement of mass in solution (chemical erosion) and mass moved via mechanical processes (physical erosion). At the hillslope scale, physical and chemical erosion rates can be quantified by combining measurements of regolith chemistry with cosmogenic nuclide concentrations in bedrock and sediment, while basin-scale rates are often inferred from riverine solute and sediment loads. These techniques integrate the effects of numerous weathering and erosion mechanisms and do not provide prima facie information about the precise nature and scale of those mechanisms. For insight into erosional process, physical erosion has been considered in terms of two limiting regimes. When physical erosion outpaces weathering front advance, regolith is mobilized downslope as soon as it is sufficiently loosened by weathering, and physical erosion rates are limited by rates of mobile regolith production. This is commonly termed weathering-limited erosion. Conversely, when weathering front advance outpaces erosion, the mobile regolith layer grows thicker over time, and physical erosion rates are limited by the efficiency of downslope transport processes. This is termed transport-limited erosion. This terminology brings the description of hillslope evolution closer to the realm of essential realism, to the extent that measurable quantities from the field can be cast in a process-based framework. An analogous process-limitation framework describes chemical erosion. In supply-limited chemical erosion, chemical weathering depletes regolith of its reactive phases during residence on a hillslope, and chemical erosion rates are limited by the supply of fresh minerals to the weathering zone. Alternatively, hillslopes may exhibit kinetic-limited chemical erosion, where physical erosion transports regolith downslope before weatherable phases are completely removed by chemical erosion. We show how supply- and

Stereochemistry of Furfural Reduction by a Saccharomyces cerevisiae Aldehyde Reductase That Contributes to In Situ Furfural Detoxification▿

PubMed Central

Bowman, Michael J.; Jordan, Douglas B.; Vermillion, Karl E.; Braker, Jay D.; Moon, Jaewoong; Liu, Z. Lewis

2010-01-01

Ari1p from Saccharomyces cerevisiae, recently identified as an intermediate-subclass short-chain dehydrogenase/reductase, contributes in situ to the detoxification of furfural. Furfural inhibits efficient ethanol production by yeast, particularly when the carbon source is acid-treated lignocellulose, which contains furfural at a relatively high concentration. NADPH is Ari1p's best known hydride donor. Here we report the stereochemistry of the hydride transfer step, determined by using (4R)-[4-2H]NADPD and (4S)-[4-2H]NADPD and unlabeled furfural in Ari1p-catalyzed reactions and following the deuterium atom into products 2-furanmethanol or NADP+. Analysis of the products demonstrates unambiguously that Ari1p directs hydride transfer from the si face of NADPH to the re face of furfural. The singular orientation of substrates enables construction of a model of the Michaelis complex in the Ari1p active site. The model reveals hydrophobic residues near the furfural binding site that, upon mutation, may increase specificity for furfural and enhance enzyme performance. Using (4S)-[4-2H]NADPD and NADPH as substrates, primary deuterium kinetic isotope effects of 2.2 and 2.5 were determined for the steady-state parameters kcatNADPH and kcat/KmNADPH, respectively, indicating that hydride transfer is partially rate limiting to catalysis. PMID:20525870

Mediating role of activity level in the depressive realism effect.

PubMed

Blanco, Fernando; Matute, Helena; A Vadillo, Miguel

2012-01-01

Several classic studies have concluded that the accuracy of identifying uncontrollable situations depends heavily on depressive mood. Nondepressed participants tend to exhibit an optimistic illusion of control, whereas depressed participants tend to better detect a lack of control. Recently, we suggested that the different activity levels (measured as the probability of responding during a contingency learning task) exhibited by depressed and nondepressed individuals is partly responsible for this effect. The two studies presented in this paper provide further support for this mediational hypothesis, in which mood is the distal cause of the illusion of control operating through activity level, the proximal cause. In Study 1, the probability of responding, P(R), was found to be a mediator variable between the depressive symptoms and the judgments of control. In Study 2, we intervened directly on the mediator variable: The P(R) for both depressed and nondepressed participants was manipulated through instructions. Our results confirm that P(R) manipulation produced differences in the participants' perceptions of uncontrollability. Importantly, the intervention on the mediator variable cancelled the effect of the distal cause; the participants' judgments of control were no longer mood dependent when the P(R) was manipulated. This result supports the hypothesis that the so-called depressive realism effect is actually mediated by the probability of responding.

The quantum Hall effects: Philosophical approach

NASA Astrophysics Data System (ADS)

Lederer, P.

2015-05-01

The Quantum Hall Effects offer a rich variety of theoretical and experimental advances. They provide interesting insights on such topics as gauge invariance, strong interactions in Condensed Matter physics, emergence of new paradigms. This paper focuses on some related philosophical questions. Various brands of positivism or agnosticism are confronted with the physics of the Quantum Hall Effects. Hacking's views on Scientific Realism, Chalmers' on Non-Figurative Realism are discussed. It is argued that the difficulties with those versions of realism may be resolved within a dialectical materialist approach. The latter is argued to provide a rational approach to the phenomena, theory and ontology of the Quantum Hall Effects.

Mapping language to visual referents: Does the degree of image realism matter?

PubMed

Saryazdi, Raheleh; Chambers, Craig G

2018-01-01

Studies of real-time spoken language comprehension have shown that listeners rapidly map unfolding speech to available referents in the immediate visual environment. This has been explored using various kinds of 2-dimensional (2D) stimuli, with convenience or availability typically motivating the choice of a particular image type. However, work in other areas has suggested that certain cognitive processes are sensitive to the level of realism in 2D representations. The present study examined the process of mapping language to depictions of objects that are more or less realistic, namely photographs versus clipart images. A custom stimulus set was first created by generating clipart images directly from photographs of real objects. Two visual world experiments were then conducted, varying whether referent identification was driven by noun or verb information. A modest benefit for clipart stimuli was observed during real-time processing, but only for noun-driving mappings. The results are discussed in terms of their implications for studies of visually situated language processing. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Survey of CIG Data Base Generation from Imagery.

DTIC Science & Technology

1980-09-01

world as measured by training transfer. There is no conclusive research as to therequired degree of realism or fidelity necessary to train. In order to...driving force behind emphasizing perceptual fidelity as opposed to realisn is the high cost of realism . Replication of all sensible attri- butes of the...and specification of visual simulation systems will con- tinue to je based on physical fidelity to the real world until those trade-offs on realism

Versatile transformations of hydrocarbons in anaerobic bacteria: substrate ranges and regio- and stereo-chemistry of activation reactions†

PubMed Central

Jarling, René; Kühner, Simon; Basílio Janke, Eline; Gruner, Andrea; Drozdowska, Marta; Golding, Bernard T.; Rabus, Ralf; Wilkes, Heinz

2015-01-01

Anaerobic metabolism of hydrocarbons proceeds either via addition to fumarate or by hydroxylation in various microorganisms, e.g., sulfate-reducing or denitrifying bacteria, which are specialized in utilizing n-alkanes or alkylbenzenes as growth substrates. General pathways for carbon assimilation and energy gain have been elucidated for a limited number of possible substrates. In this work the metabolic activity of 11 bacterial strains during anaerobic growth with crude oil was investigated and compared with the metabolite patterns appearing during anaerobic growth with more than 40 different hydrocarbons supplied as binary mixtures. We show that the range of co-metabolically formed alkyl- and arylalkyl-succinates is much broader in n-alkane than in alkylbenzene utilizers. The structures and stereochemistry of these products are resolved. Furthermore, we demonstrate that anaerobic hydroxylation of alkylbenzenes does not only occur in denitrifiers but also in sulfate reducers. We propose that these processes play a role in detoxification under conditions of solvent stress. The thermophilic sulfate-reducing strain TD3 is shown to produce n-alkylsuccinates, which are suggested not to derive from terminal activation of n-alkanes, but rather to represent intermediates of a metabolic pathway short-cutting fumarate regeneration by reverse action of succinate synthase. The outcomes of this study provide a basis for geochemically tracing such processes in natural habitats and contribute to an improved understanding of microbial activity in hydrocarbon-rich anoxic environments. PMID:26441848

A modified Wright-Fisher model that incorporates Ne: A variant of the standard model with increased biological realism and reduced computational complexity.

PubMed

Zhao, Lei; Gossmann, Toni I; Waxman, David

2016-03-21

The Wright-Fisher model is an important model in evolutionary biology and population genetics. It has been applied in numerous analyses of finite populations with discrete generations. It is recognised that real populations can behave, in some key aspects, as though their size that is not the census size, N, but rather a smaller size, namely the effective population size, Ne. However, in the Wright-Fisher model, there is no distinction between the effective and census population sizes. Equivalently, we can say that in this model, Ne coincides with N. The Wright-Fisher model therefore lacks an important aspect of biological realism. Here, we present a method that allows Ne to be directly incorporated into the Wright-Fisher model. The modified model involves matrices whose size is determined by Ne. Thus apart from increased biological realism, the modified model also has reduced computational complexity, particularly so when Ne⪡N. For complex problems, it may be hard or impossible to numerically analyse the most commonly-used approximation of the Wright-Fisher model that incorporates Ne, namely the diffusion approximation. An alternative approach is simulation. However, the simulations need to be sufficiently detailed that they yield an effective size that is different to the census size. Simulations may also be time consuming and have attendant statistical errors. The method presented in this work may then be the only alternative to simulations, when Ne differs from N. We illustrate the straightforward application of the method to some problems involving allele fixation and the determination of the equilibrium site frequency spectrum. We then apply the method to the problem of fixation when three alleles are segregating in a population. This latter problem is significantly more complex than a two allele problem and since the diffusion equation cannot be numerically solved, the only other way Ne can be incorporated into the analysis is by simulation. We have

Constructing the principles: Method and metaphysics in the progress of theoretical physics

NASA Astrophysics Data System (ADS)

Glass, Lawrence C.

This thesis presents a new framework for the philosophy of physics focused on methodological differences found in the practice of modern theoretical physics. The starting point for this investigation is the longstanding debate over scientific realism. Some philosophers have argued that it is the aim of science to produce an accurate description of the world including explanations for observable phenomena. These scientific realists hold that our best confirmed theories are approximately true and that the entities they propose actually populate the world, whether or not they have been observed. Others have argued that science achieves only frameworks for the prediction and manipulation of observable phenomena. These anti-realists argue that truth is a misleading concept when applied to empirical knowledge. Instead, focus should be on the empirical adequacy of scientific theories. This thesis argues that the fundamental distinction at issue, a division between true scientific theories and ones which are empirically adequate, is best explored in terms of methodological differences. In analogy with the realism debate, there are at least two methodological strategies. Rather than focusing on scientific theories as wholes, this thesis takes as units of analysis physical principles which are systematic empirical generalizations. The first possible strategy, the conservative, takes the assumption that the empirical adequacy of a theory in one domain serves as good evidence for such adequacy in other domains. This then motivates the application of the principle to new domains. The second strategy, the innovative, assumes that empirical adequacy in one domain does not justify the expectation of adequacy in other domains. New principles are offered as explanations in the new domain. The final part of the thesis is the application of this framework to two examples. On the first, Lorentz's use of the aether is reconstructed in terms of the conservative strategy with respect to

Reflections on the nature of the concepts of field in physics

NASA Astrophysics Data System (ADS)

Pombo, C.

2012-12-01

This paper is a short introduction on the analysis of the concepts of field in physics, showing their different natures. It comprises a study on the development of observers based on observational realism, a physical epistemology in development, on the basis of analytical psychology. This epistemology incorporates and justify the proposition of R. Carnap, of separating observational and theoretical domains of a theory, and gives a criterion for this separation. The basis of three theories are discussed, where concepts of field emerge. We discuss the different origins and meanings of these fields, from an epistemological point of view, in their respective theories. The aim of this paper is to form a basis of discussion to be applied in the analysis of other theories where concepts of field are present, to reach a better understanding of the contemporary programs of unification. We would like to clarify if these programs are intended for unification of fields as elements of the physical reality, fields as explanations for the observations, unification of their theories, or other possible cases.

[Critical Review of Gender Ideology in the Light of Metaphysical Realism].

PubMed

Burguete Miguel, Enrique Eduardo

2018-01-01

The implementing of gender ideology in the imaginary of current welfare-state societies owes much to a long process in the history of thought, which has culminated in an accommodation of post-feminist discourse. This paper sets out the epistemological principles that are present in gender ideology, as a response to both its recent and more-remote antecedents. It is furthermore framed by an urge for emancipation that began with medieval scholasticism, the latest manifestation of which lies in the post-structuralist deconstructionism that outlines the concept of queer. This concept has dissociated the categories of sex and gender to the point of making them irrelevant for the determination of sexual identity, leaving the latter susceptible to being infinitely de- and reconstructed. This article also reviews the liberal-hedonistic context of the new postmodern setting, while showing how the concepts of ″a subjective feeling of happiness″ and ″a life fulfilled″ do not express similar content. The paper goes on to challenge the theory of gender from the perspective of metaphysic realism; stressing that the human being only appears as a real person via the possibility of anticipating another's contemplation, thereby cancelling out the abstraction of pure subjectivity. It finally offers its conclusions, with certain substantive recommendations in the field of education.

CYP2C9 Amino Acid Residues Influencing Phenytoin Turnover and Metabolite Regio- and Stereochemistry

PubMed Central

Mosher, Carrie M.; Tai, Guoying; Rettie, Allan E.

2009-01-01

Phenytoin has been an effective anticonvulsant agent for over 60 years, although its clinical use is complicated by nonlinear pharmacokinetics, a narrow therapeutic index, and metabolically based drug-drug interactions. Although it is well established that CYP2C9 is the major cytochrome P450 enzyme controlling metabolic elimination of phenytoin through its oxidative conversion to (S)-5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH), nothing is known about the amino acid binding determinants within the CYP2C9 active site that promote metabolism and maintain the tight stereocontrol of hydroxy metabolite formation. This knowledge gap was addressed here through the construction of nine active site mutants at amino acid positions Phe100, Arg108, Phe114, Leu208, and Phe476 and in vitro analysis of the steady-state kinetics and stereochemistry of p-HPPH formation. The F100L and F114W mutants exhibited 4- to 5-fold increases in catalytic efficiency, whereas the F100W, F114L, F476L, and F476W mutants lost >90% of their phenytoin hydroxylation capacity. This pattern of effects differs substantially from that found previously for (S)-warfarin and (S)-flurbiprofen metabolism, suggesting that these three ligands bind within discrete locations in the CYP2C9 active site. Only the F114L, F476L, and L208V mutants altered phenytoin's orientation during catalytic turnover. The L208V mutant also uniquely demonstrated enhanced 6-hydroxylation of (S)-warfarin. These latter data provide the first experimental evidence for a role of the F-G loop region in dictating the catalytic orientation of substrates within the CYP2C9 active site. PMID:19258521

Beyond idealism and realism: Canadian NGO/government relations during the negotiation of the FCTC.

PubMed

Lencucha, Raphael; Labonté, Ronald; Rouse, Michael J

2010-04-01

The Framework Convention on Tobacco Control (FCTC) marks a unique point in the history of global health governance. This convention produced the first legally binding treaty under the auspices of the World Health Organization. Another first was the extent to which non-governmental organizations (NGOs) participated in the negotiation process. This article explores the relationship between one group of NGOs and their respective government during the negotiation of the FCTC. Documentary analyses and 18 individual in-depth interviews were conducted with both government and NGO representatives. In contrast to the polar perspectives of idealism (NGOs as unique and autonomous) and realism (NGOs as funded arms of the government), our findings suggest that neither opposition nor conformity on the part of the NGOs characterize the relationship between the NGOs and government. While specific to the case under study (the FCTC), our findings nonetheless indicate the need for a nuanced view of the relationship between governments and NGOs, at least during the process of multilateral health policy negotiations.

Depressive realism and outcome density bias in contingency judgments: the effect of the context and intertrial interval.

PubMed

Msetfi, Rachel M; Murphy, Robin A; Simpson, Jane; Kornbrot, Diana E

2005-02-01

The perception of the effectiveness of instrumental actions is influenced by depressed mood. Depressive realism (DR) is the claim that depressed people are particularly accurate in evaluating instrumentality. In two experiments, the authors tested the DR hypothesis using an action-outcome contingency judgment task. DR effects were a function of intertrial interval length and outcome density, suggesting that depressed mood is accompanied by reduced contextual processing rather than increased judgment accuracy. The DR effect was observed only when participants were exposed to extended periods in which no actions or outcomes occurred. This implies that DR may result from an impairment in contextual processing rather than accurate but negative expectations. Therefore, DR is consistent with a cognitive distortion view of depression. ((c) 2005 APA, all rights reserved).

Assignment of the Stereochemistry and Anomeric Configuration of Sugars within Oligosaccharides Via Overlapping Disaccharide Ladders Using MSn

NASA Astrophysics Data System (ADS)

Konda, Chiharu; Londry, Frank A.; Bendiak, Brad; Xia, Yu

2014-08-01

A systematic approach is described that can pinpoint the stereo-structures (sugar identity, anomeric configuration, and location) of individual sugar units within linear oligosaccharides. Using a highly modified mass spectrometer, dissociation of linear oligosaccharides in the gas phase was optimized along multiple-stage tandem dissociation pathways (MSn, n = 4 or 5). The instrument was a hybrid triple quadrupole/linear ion trap mass spectrometer capable of high-efficiency bidirectional ion transfer between quadrupole arrays. Different types of collision-induced dissociation (CID), either on-resonance ion trap or beam-type CID could be utilized at any given stage of dissociation, enabling either glycosidic bond cleavages or cross-ring cleavages to be maximized when wanted. The approach first involves optimizing the isolation of disaccharide units as an ordered set of overlapping substructures via glycosidic bond cleavages during early stages of MSn, with explicit intent to minimize cross-ring cleavages. Subsequently, cross-ring cleavages were optimized for individual disaccharides to yield key diagnostic product ions ( m/ z 221). Finally, fingerprint patterns that establish stereochemistry and anomeric configuration were obtained from the diagnostic ions via CID. Model linear oligosaccharides were derivatized at the reducing end, allowing overlapping ladders of disaccharides to be isolated from MSn. High confidence stereo-structural determination was achieved by matching MSn CID of the diagnostic ions to synthetic standards via a spectral matching algorithm. Using this MSn ( n = 4 or 5) approach, the stereo-structures, anomeric configurations, and locations of three individual sugar units within two pentasaccharides were successfully determined.

Hydrophobic Tail Length, Degree of Fluorination and Headgroup Stereochemistry are Determinants of the Biocompatibility of (Fluorinated) Carbohydrate Surfactants

PubMed Central

Li, Xueshu; Turánek, Jaroslav; Knötigová, Pavlína; Kudláčková, Hana; Mašek, Josef; Parkin, Sean; Rankin, Stephen E; Knutson, Barbara L; Lehmler, Hans-Joachim

2009-01-01

A series of hydrocarbon and fluorocarbon carbohydrate surfactants with different headgroups (i.e., gluco-, galacto- and maltopyranoside) and (fluorinated) alkyl tails (i.e., C7 and C14 to C19) was synthesized to investigate trends in their cytotoxicity and haemolytic activity, and how surfactant-lipid interactions of selected surfactants contribute to these two measures of biocompatibility. All surfactants displayed low cytotoxicity (EC50 = 25 to > 250 μM) and low haemolytic activity (EC50 = 0.2 to > 3.3 mM), with headgroup structure, tail length and degree of fluorination being important structural determinants for both endpoints. The EC50 values of hydrocarbon and fluorocarbon glucopyranoside surfactants displayed a “cut-off” effect (i.e., a maximum with respect to the chain length). According to steady-state fluorescence anisotropy studies, short chain (C7) surfactants partitioned less readily into model membranes, which explains their low cytotoxicity and haemolytic activity. Interestingly, galactopyranosides were less toxic compared to glucopyranosides with the same hydrophobic tail. Although both surfactant types only differ in the stereochemistry of the 4-OH group, hexadecyl gluco- and galactopyranoside surfactants had similar apparent membrane partition coefficients, but differed in their overall effect on the phase behaviour of DPPC model membranes, as assessed using steady-state fluorescence anisotropy studies. These observations suggest that highly selective surfactant-lipid interactions may be responsible for the differential cytotoxicity and, possible, haemolytic activity of hydrocarbon and fluorocarbon carbohydrate surfactants intended for a variety of pharmaceutical and biomedical applications. PMID:19481909

The priority of internal symmetries in particle physics

NASA Astrophysics Data System (ADS)

Kantorovich, Aharon

2003-12-01

In this paper, I try to decipher the role of internal symmetries in the ontological maze of particle physics. The relationship between internal symmetries and laws of nature is discussed within the framework of ;Platonic realism.; The notion of physical ;structure; is introduced as representing a deeper ontological layer behind the observable world. I argue that an internal symmetry is a structure encompassing laws of nature. The application of internal symmetry groups to particle physics came about in two revolutionary steps. The first was the introduction of the internal symmetries of hadrons in the early 1960s. These global and approximate symmetries served as means of bypassing the dynamics. I argue that the realist could interpret these symmetries as ontologically prior to the hadrons. The second step was the gauge revolution in the 1970s, where symmetries became local and exact and were integrated with the dynamics. I argue that the symmetries of the second generation are fundamental in the following two respects: (1) According to the so-called ;gauge argument,; gauge symmetry dictates the existence of gauge bosons, which determine the nature of the forces. This view, which has been recently criticized by some philosophers, is widely accepted in particle physics at least as a heuristic principle. (2) In view of grand unified theories, the new symmetries can be interpreted as ontologically prior to baryon matter.

Investigation of the dynamic stereochemistry of dimesityl-2,4,6-trimethoxyphenylmethane by complete lineshape analysis and 2D EXSY NMR spectroscopy.

PubMed

Denkova, Pavletta; Vassilev, Nikolay; Van Lokeren, Luk; Willem, Rudolph

2008-04-01

The static and dynamic stereochemistry of dimesityl-2,4,6-trimethoxyphenylmethane in solution was investigated by lineshape analysis of 1D NMR spectra and cross-peak amplitude processing in 2D EXSY spectra, recorded at variable temperatures. Previous studies on this propeller-shaped chiral compound show that the stereomer threshold interconversion is associated with helicity reversal and occurs through [1,2]- and [1,3]-two ring flips of one mesityl and the 2,4,6-trimethoxyphenyl rings. In the present study, the experimental rate constants of the [1,2]- and [1,3]-two ring flips, which are identical, were determined at various temperatures by combining quantitative 2D EXSY spectra processing and complete lineshape analysis (CLSA) of 1D NMR spectra. The latter were subjected to reference deconvolution and linear prediction in order to eliminate the lineshape distortions due to magnetic field inhomogeneity. The activation parameters of these ring flips were determined by an Eyring equation analysis of the temperature dependence of the rate constant. The experimentally determined activation enthalpy and entropy for the two-ring flips, and those obtained from theoretical ab initio calculations at different levels of theory and basis sets, were found to be in good agreement. Copyright (c) 2008 John Wiley & Sons, Ltd.

Testing quantum mechanics against macroscopic realism using the output of {chi}{sup (2)} nonlinearity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Podoshvedov, Sergey A.; Kim, Jaewan

2006-09-15

We suggest an all-optical scheme to generate entangled superposition of a single photon with macroscopic entangled states for testing macroscopic realism. The scheme consists of source of single photons, a Mach-Zehnder interferometer in routes of which a system of coupled-down converters with type-I phase matching is inserted, and a beam splitter for the other auxiliary modes of the scheme. We use quantization of the pumping modes, depletion of the coherent states passing through the system, and interference effect in the pumping modes in the process of erasing which-path information of the single-photon on exit from the Mach-Zehnder interferometer. We showmore » the macroscopic fields of the output superposition are distinguishable states. This scheme generates macroscopic entangled state that violates Bell's inequality. Moreover, the detailed analysis concerning change of amplitudes of entangled superposition by means of repeating this process many times is accomplished. We show our scheme works without photon number resolving detection and it is robust to detector inefficiency.« less

About the Undecidable Thing of Onthologic Truth of the Reality of the Fundamental Physics

NASA Astrophysics Data System (ADS)

Amaya, J. M.; Carbonell, M. V.; Martínez, E.; Flórez, M.

2007-04-01

In the philosophy of contemporary science, different currents from thought have been arising, each one of which, it has developed methodologies that include a set of normative rules for the evaluation that must decide the acceptance or rejection of the scientific theories already elaborated. These methodologies, rivals to each other, are: "Inductivism", "Conventionalism", "Falsacionism" and the "Theories like structures" (Kühn and Lakatos). These evaluative methodologies of the quality and validity of the scientific knowledge (or metatheories of science) associate a epistemological validation as soon as until limit or border of science forms, it presents/displays and it describes the observable world as well as the one that there is behind the appearances. Consequence of it has been the appearance of different valorative interpretations from the representation that the scientific theories give us of which reality is called, such as "Scientific realism", "Antirealism", "Conjectural realism", "Structural realism" etc that has based their theses on the problem on language, truth and reality.

Bioorganic Chemistry. A Natural Reunion of the Physical and Life Sciences

PubMed Central

Poulter, C. Dale

2009-01-01

Organic substances were conceived as those found in living organisms. Although the definition was soon broadened to include all carbon-containing compounds, naturally occurring molecules have always held a special fascination for organic chemists. From these beginnings, molecules from nature were indespensible tools as generations of organic chemists developed new techniques for determining structures, analyzed the mechanisms of reactions, explored the effects conformation and stereochemistry on reactions, and found challenging new targets to synthesize. Only recently have organic chemists harnessed the powerful techniques of organic chemistry to study the functions of organic molecules in their biological hosts, the enzymes that synthesize molecules and the complex processes that occur in a cell. In this Perspective, I present a personal account my entrée into bioorganic chemistry as a physical organic chemist and subsequent work to understand the chemical mechanisms of enzyme-catalyzed reactions, to develop techniques to identify and assign hydrogen bonds in tRNAs through NMR studies with isotopically labeled molecules, and to study how structure determines function in biosynthetic enzymes with proteins obtained by genetic engineering. PMID:19323569

Evaluating Remapped Physical Reach for Hand Interactions with Passive Haptics in Virtual Reality.

PubMed

Han, Dustin T; Suhail, Mohamed; Ragan, Eric D

2018-04-01

Virtual reality often uses motion tracking to incorporate physical hand movements into interaction techniques for selection and manipulation of virtual objects. To increase realism and allow direct hand interaction, real-world physical objects can be aligned with virtual objects to provide tactile feedback and physical grasping. However, unless a physical space is custom configured to match a specific virtual reality experience, the ability to perfectly match the physical and virtual objects is limited. Our research addresses this challenge by studying methods that allow one physical object to be mapped to multiple virtual objects that can exist at different virtual locations in an egocentric reference frame. We study two such techniques: one that introduces a static translational offset between the virtual and physical hand before a reaching action, and one that dynamically interpolates the position of the virtual hand during a reaching motion. We conducted two experiments to assess how the two methods affect reaching effectiveness, comfort, and ability to adapt to the remapping techniques when reaching for objects with different types of mismatches between physical and virtual locations. We also present a case study to demonstrate how the hand remapping techniques could be used in an immersive game application to support realistic hand interaction while optimizing usability. Overall, the translational technique performed better than the interpolated reach technique and was more robust for situations with larger mismatches between virtual and physical objects.

Effects of realism on extended violent and nonviolent video game play on aggressive thoughts, feelings, and physiological arousal.

PubMed

Barlett, Christopher P; Rodeheffer, Christopher

2009-01-01

Previous research has shown that playing violent video game exposure can increase aggressive thoughts, aggressive feelings, and physiological arousal. This study compared the effects that playing a realistic violent, unrealistic violent, or nonviolent video game for 45 min has on such variables. For the purpose of this study, realism was defined as the probability of seeing an event in real life. Participants (N=74; 39 male, 35 female) played either a realistic violent, unrealistic violent, or nonviolent video game for 45 min. Aggressive thoughts and aggressive feelings were measured four times (every 15 min), whereas arousal was measured continuously. The results showed that, though playing any violent game stimulated aggressive thoughts, playing a more realistic violent game stimulated significantly more aggressive feelings and arousal over the course of play. Copyright 2009 Wiley-Liss, Inc.

Physically-Based Rendering of Particle-Based Fluids with Light Transport Effects

NASA Astrophysics Data System (ADS)

Beddiaf, Ali; Babahenini, Mohamed Chaouki

2018-03-01

Recent interactive rendering approaches aim to efficiently produce images. However, time constraints deeply affect their output accuracy and realism (many light phenomena are poorly or not supported at all). To remedy this issue, in this paper, we propose a physically-based fluid rendering approach. First, while state-of-the-art methods focus on isosurface rendering with only two refractions, our proposal (1) considers the fluid as a heterogeneous participating medium with refractive boundaries, and (2) supports both multiple refractions and scattering. Second, the proposed solution is fully particle-based in the sense that no particles transformation into a grid is required. This interesting feature makes it able to handle many particle types (water, bubble, foam, and sand). On top of that, a medium with different fluids (color, phase function, etc.) can also be rendered.

Towards a physically-based multi-scale ecohydrological simulator for semi-arid regions

NASA Astrophysics Data System (ADS)

Caviedes-Voullième, Daniel; Josefik, Zoltan; Hinz, Christoph

2017-04-01

The use of numerical models as tools for describing and understanding complex ecohydrological systems has enabled to test hypothesis and propose fundamental, process-based explanations of the system system behaviour as a whole as well as its internal dynamics. Reaction-diffusion equations have been used to describe and generate organized pattern such as bands, spots, and labyrinths using simple feedback mechanisms and boundary conditions. Alternatively, pattern-matching cellular automaton models have been used to generate vegetation self-organization in arid and semi-arid regions also using simple description of surface hydrological processes. A key question is: How much physical realism is needed in order to adequately capture the pattern formation processes in semi-arid regions while reliably representing the water balance dynamics at the relevant time scales? In fact, redistribution of water by surface runoff at the hillslope scale occurs at temporal resolution of minutes while the vegetation development requires much lower temporal resolution and longer times spans. This generates a fundamental spatio-temporal multi-scale problem to be solved, for which high resolution rainfall and surface topography are required. Accordingly, the objective of this contribution is to provide proof-of-concept that governing processes can be described numerically at those multiple scales. The requirements for a simulating ecohydrological processes and pattern formation with increased physical realism are, amongst others: i. high resolution rainfall that adequately captures the triggers of growth as vegetation dynamics of arid regions respond as pulsed systems. ii. complex, natural topography in order to accurately model drainage patterns, as surface water redistribution is highly sensitive to topographic features. iii. microtopography and hydraulic roughness, as small scale variations do impact on large scale hillslope behaviour iv. moisture dependent infiltration as temporal

Scientist's Idealism Vs. User's Realism for Orthorectification of Full Radarsat-2/Compact RCM Polarimetric Data with DSM

NASA Astrophysics Data System (ADS)

Toutin, Thierry; Wang, Huili; Charbonneau, Francois; Schmitt, Carla

2013-08-01

This paper presented two methods for the orthorectification of full/compact polarimetric SAR data: the polarimetric processing is performed in the image space (scientist's idealism) or in the ground space (user's realism) before or after the geometric processing, respectively. Radarsat-2 (R2) fine-quad and simulated very high-resolution RCM data acquired with different look angles over a hilly relief study site were processed using accurate lidar digital surface model. Quantitative evaluations between the two methods as a function of different geometric and radiometric parameters were performed to evaluate the impact during the orthorectification. The results demonstrated that the ground-space method can be safely applied to polarimetric R2 SAR data with an exception with the steep look angles and steep terrain slopes. On the other hand, the ground-space method cannot be applied to simulated compact RCM data due to 17dB noise floor and oversampling.

Contextualism adds realism: nursing students' perceptions of and performance in numeracy skills tests.

PubMed

Ramjan, Lucie M

2011-11-01

This project investigated nursing students' perceptions of and performance in a de-contextualised diagnostic maths paper (i.e. questions only) and a contextualised diagnostic maths paper (i.e. visual pictures along with questions). Sampling was purposive, the criteria being that participants would be from the population of student nurses (n=700) in their second year, of a three-year Bachelor of Nursing course, undertaking a Unit 'Medical-Surgical Nursing 1' (MSN1) at one of four campuses across the University of Western Sydney (UWS), NSW, Australia. The numerical test scores for both papers were analysed with the assistance of SPSS software and a Professional Development Officer. The survey data were analysed manually and thematically by the researcher. There was a substantive improvement in scores from Test 1 (de-contextualised) to Test 2 (contextualised). It is uncertain whether the change occurred because Test 2 is a genuinely better presentation than Test 1 or just a practice effect. Nevertheless, the contextualised paper was preferred by the majority of students (80%). Students preferred the visual images and revealed that it led to a "deeper learning" of numeracy skills, reduced stress and anxiety levels and simulated 'the real life' clinical setting, thus adding "an element of realism" to the situation. Copyright © 2010 Elsevier Ltd. All rights reserved.

Feeling and Time: The Phenomenology of Mood Disorders, Depressive Realism, and Existential Psychotherapy

PubMed Central

Ghaemi, S. Nassir

2007-01-01

Phenomenological research suggests that pure manic and depressive states are less common than mixtures of the two and that the two poles of mood are characterized by opposite ways of experiencing time. In mania, the subjective experience of time is sped up and in depression it is slowed down, perhaps reflecting differences in circadian pathophysiology. The two classic mood states are also quite different in their effect on subjective awareness: manic patients lack insight into their excitation, while depressed patients are quite insightful into their unhappiness. Consequently, insight plays a major role in overdiagnosis of unipolar depression and misdiagnosis of bipolar disorder. The phenomenology of depression also is relevant to types of psychotherapies used to treat it. The depressive realism (DR) model, in contrast to the cognitive distortion model, appears to better apply to many persons with mild to moderate depressive syndromes. I suggest that existential psychotherapy is the necessary corollary of the DR model in those cases. Further, some depressive morbidities may in fact prove, after phenomenological study, to involve other mental states instead of depression. The chronic subsyndromal depression that is often the long-term consequence of treated bipolar disorder may in fact represent existential despair, rather than depression proper, again suggesting intervention with existential psychotherapeutic methods. PMID:17122410

Statistical strength of experiments to reject local realism with photon pairs and inefficient detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Yanbao; Mathematical and Computational Sciences Division, National Institute of Standards and Technology, Boulder, Colorado, 80305; Knill, Emanuel

2010-03-15

Because of the fundamental importance of Bell's theorem, a loophole-free demonstration of a violation of local realism (LR) is highly desirable. Here, we study violations of LR involving photon pairs. We quantify the experimental evidence against LR by using measures of statistical strength related to the Kullback-Leibler (KL) divergence, as suggested by van Dam et al.[W. van Dam, R. D. Gill, and P. D. Grunwald, IEEE Trans. Inf. Theory. 51, 2812 (2005)]. Specifically, we analyze a test of LR with entangled states created from two independent polarized photons passing through a polarizing beam splitter. We numerically study the detection efficiencymore » required to achieve a specified statistical strength for the rejection of LR depending on whether photon counters or detectors are used. Based on our results, we find that a test of LR free of the detection loophole requires photon counters with efficiencies of at least 89.71%, or photon detectors with efficiencies of at least 91.11%. For comparison, we also perform this analysis with ideal unbalanced Bell states, which are known to allow rejection of LR with detector efficiencies above 2/3.« less

Holism and structuralism in U(1) gauge theory

NASA Astrophysics Data System (ADS)

Lyre, Holger

After decades of neglect philosophers of physics have discovered gauge theories-arguably the paradigm of modern field physics-as a genuine topic for foundational and philosophical research. Incidentally, in the last couple of years interest from the philosophy of physics in structural realism-in the eyes of its proponents the best suited realist position towards modern physics-has also raised. This paper tries to connect both topics and aims to show that structural realism gains further credence from an ontological analysis of gauge theories-in particular U (1) gauge theory. In the first part of the paper the framework of fiber bundle gauge theories is briefly presented and the interpretation of local gauge symmetry will be examined. In the second part, an ontological underdetermination of gauge theories is carved out by considering the various kinds of non-locality involved in such typical effects as the Aharonov-Bohm effect. The analysis shows that the peculiar form of non-separability figuring in gauge theories is a variant of spatiotemporal holism and can be distinguished from quantum theoretic holism. In the last part of the paper the arguments for a gauge theoretic support of structural realism are laid out and discussed.

Does Quantum Physics Refute Realism, Materialism and Determinism?

ERIC Educational Resources Information Center

Bunge, Mario

2012-01-01

It is argued that the correct answer to the three questions in the title is "no": that the theses being denied derive from traditional philosophy, not from the way the quantum theories are used. For example, the calculation of the energy spectrum of an atom assumes the autonomous existence of the atom, rather than its dependence upon the observer.…

From Dualism to Unity in Quantum Physics

NASA Astrophysics Data System (ADS)

Landé, Alfred

2016-02-01

Preface; Introduction; 1. Causality, chance, continuity; 2. States, observables, probabilities; 3. The metric law of probabilities; 4. Quantum dynamics; 5. Quantum fact and fiction; Retrospect. From dualism to unity, from positivism to realism; Appendix 1. Survey of elementary postulates; Appendix 2. Two problems of uniqueness; References; Index.

A review of stereochemical implications in the generation of secondary organic aerosol from isoprene oxidation.

PubMed

Cash, James M; Heal, Mathew R; Langford, Ben; Drewer, Julia

2016-11-09

The atmospheric reactions leading to the generation of secondary organic aerosol (SOA) from the oxidation of isoprene are generally assumed to produce only racemic mixtures, but aspects of the chemical reactions suggest this may not be the case. In this review, the stereochemical outcomes of published isoprene-degradation mechanisms contributing to high amounts of SOA are evaluated. Despite evidence suggesting isoprene first-generation oxidation products do not contribute to SOA directly, this review suggests the stereochemistry of first-generation products may be important because their stereochemical configurations may be retained through to the second-generation products which form SOA. Specifically, due to the stereochemistry of epoxide ring-opening mechanisms, the outcome of the reactions involving epoxydiols of isoprene (IEPOX), methacrylic acid epoxide (MAE) and hydroxymethylmethyl-α-lactone (HMML) are, in principle, stereospecific which indicates the stereochemistry is predefined from first-generation precursors. The products from these three epoxide intermediates oligomerise to form macromolecules which are proposed to form chiral structures within the aerosol and are considered to be the largest contributors to SOA. If conditions in the atmosphere such as pH, aerosol water content, relative humidity, pre-existing aerosol, aerosol coatings and aerosol cation/anion content (and other) variables acting on the reactions leading to SOA affect the tacticity (arrangement of chiral centres) in the SOA then they may influence its physical properties, for example its hygroscopicity. Chamber studies of SOA formation from isoprene encompass particular sets of controlled conditions of these variables. It may therefore be important to consider stereochemistry when upscaling from chamber study data to predictions of SOA yields across the range of ambient atmospheric conditions. Experiments analysing the stereochemistry of the reactions under varying conditions of the

Template-free modeling by LEE and LEER in CASP11.

PubMed

Joung, InSuk; Lee, Sun Young; Cheng, Qianyi; Kim, Jong Yun; Joo, Keehyoung; Lee, Sung Jong; Lee, Jooyoung

2016-09-01

For the template-free modeling of human targets of CASP11, we utilized two of our modeling protocols, LEE and LEER. The LEE protocol took CASP11-released server models as the input and used some of them as templates for 3D (three-dimensional) modeling. The template selection procedure was based on the clustering of the server models aided by a community detection method of a server-model network. Restraining energy terms generated from the selected templates together with physical and statistical energy terms were used to build 3D models. Side-chains of the 3D models were rebuilt using target-specific consensus side-chain library along with the SCWRL4 rotamer library, which completed the LEE protocol. The first success factor of the LEE protocol was due to efficient server model screening. The average backbone accuracy of selected server models was similar to that of top 30% server models. The second factor was that a proper energy function along with our optimization method guided us, so that we successfully generated better quality models than the input template models. In 10 out of 24 cases, better backbone structures than the best of input template structures were generated. LEE models were further refined by performing restrained molecular dynamics simulations to generate LEER models. CASP11 results indicate that LEE models were better than the average template models in terms of both backbone structures and side-chain orientations. LEER models were of improved physical realism and stereo-chemistry compared to LEE models, and they were comparable to LEE models in the backbone accuracy. Proteins 2016; 84(Suppl 1):118-130. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Causal reports: Context-dependent contributions of intuitive physics and visual impressions of launching.

PubMed

Vicovaro, Michele

2018-05-01

Everyday causal reports appear to be based on a blend of perceptual and cognitive processes. Causality can sometimes be perceived automatically through low-level visual processing of stimuli, but it can also be inferred on the basis of an intuitive understanding of the physical mechanism that underlies an observable event. We investigated how visual impressions of launching and the intuitive physics of collisions contribute to the formation of explicit causal responses. In Experiment 1, participants observed collisions between realistic objects differing in apparent material and hence implied mass, whereas in Experiment 2, participants observed collisions between abstract, non-material objects. The results of Experiment 1 showed that ratings of causality were mainly driven by the intuitive physics of collisions, whereas the results of Experiment 2 provide some support to the hypothesis that ratings of causality were mainly driven by visual impressions of launching. These results suggest that stimulus factors and experimental design factors - such as the realism of the stimuli and the variation in the implied mass of the colliding objects - may determine the relative contributions of perceptual and post-perceptual cognitive processes to explicit causal responses. A revised version of the impetus transmission heuristic provides a satisfactory explanation for these results, whereas the hypothesis that causal responses and intuitive physics are based on the internalization of physical laws does not. Copyright © 2018 Elsevier B.V. All rights reserved.

Pattern cladistics and the 'realism-antirealism debate' in the philosophy of biology.

PubMed

Vergara-Silva, Francisco

2009-06-01

Despite the amount of work that has been produced on the subject over the years, the 'transformation of cladistics' is still a misunderstood episode in the history of comparative biology. Here, I analyze two outstanding, highly contrasting historiographic accounts on the matter, under the perspective of an influential dichotomy in the philosophy of science: the opposition between Scientific Realism and Empiricism. Placing special emphasis on the notion of 'causal grounding' of morphological characters (sensu Olivier Rieppel) in modern developmental biology's (mechanistic) theories, I arrive at the conclusion that a 'new transformation of cladistics' is philosophically plausible. This 'reformed' understanding of 'pattern cladistics' entails retaining the interpretation of cladograms as 'schemes of synapomorphies', but in association to construing cladogram nodes as 'developmental-genetic taxic homologies', instead of 'standard Darwinian ancestors'. The reinterpretation of pattern cladistics presented here additionally proposes to take Bas Van Fraassen's 'constructive empiricism' as a philosophical stance that could properly support such analysis of developmental-genetic data for systematic purposes. The latter suggestion is justified through a reappraisal of previous ideas developed by prominent pattern cladists (mainly, Colin Patterson), which concerned a scientifically efficient 'observable/non-observable distinction' linked to the conceptual pair 'ontogeny and phylogeny'. Finally, I argue that a robust articulation of Antirealist alternatives in systematics may provide a rational basis for its disciplinary separation from evolutionary biology, as well as for a critical reconsideration of the proper role of certain Scientific Realist positions, currently popular in comparative biology.

Stereochemistry of C18 monounsaturated cork suberin acids determined by spectroscopic techniques including (1) H-NMR multiplet analysis of olefinic protons.

PubMed

Santos, Sara; Graça, José

2014-01-01

Suberin is a biopolyester responsible for the protection of secondary plant tissues, and yet its molecular structure remains unknown. The C18:1 ω-hydroxyacid and the C18:1 α,ω-diacid are major monomers in the suberin structure, but the configuration of the double bond remains to be elucidated. To unequivocally define the configuration of the C18:1 suberin acids. Pure C18:1 ω-hydroxyacid and C18:1 α,ω-diacid, isolated from cork suberin, and two structurally very close C18:1 model compounds of known stereochemistry, methyl oleate and methyl elaidate, were analysed by NMR spectroscopy, Fourier transform infrared (FTIR) and Raman spectroscopy, and GC-MS. The GC-MS analysis showed that both acids were present in cork suberin as only one geometric isomer. The analysis of dimethyloxazoline (DMOX) and picolinyl derivatives proved the double bond position to be at C-9. The FTIR spectra were concordant with a cis-configuration for both suberin acids, but their unambiguous stereochemical assignment came from the NMR analysis: (i) the chemical shifts of the allylic (13) C carbons were shielded comparatively to the trans model compound, and (ii) the complex multiplets of the olefinic protons could be simulated only with (3) JHH and long-range (4) JHH coupling constants typical of a cis geometry. The two C18:1 suberin acids in cork are (Z)-18-hydroxyoctadec-9-enoic acid and (Z)-octadec-9-enedoic acid. Copyright © 2013 John Wiley & Sons, Ltd.

Test of a hypothesis of realism in quantum theory using a Bayesian approach

NASA Astrophysics Data System (ADS)

Nikitin, N.; Toms, K.

2017-05-01

In this paper we propose a time-independent equality and time-dependent inequality, suitable for an experimental test of the hypothesis of realism. The derivation of these relations is based on the concept of conditional probability and on Bayes' theorem in the framework of Kolmogorov's axiomatics of probability theory. The equality obtained is intrinsically different from the well-known Greenberger-Horne-Zeilinger (GHZ) equality and its variants, because violation of the proposed equality might be tested in experiments with only two microsystems in a maximally entangled Bell state |Ψ-> , while a test of the GHZ equality requires at least three quantum systems in a special state |ΨGHZ> . The obtained inequality differs from Bell's, Wigner's, and Leggett-Garg inequalities, because it deals with spin s =1 /2 projections onto only two nonparallel directions at two different moments of time, while a test of the Bell and Wigner inequalities requires at least three nonparallel directions, and a test of the Leggett-Garg inequalities requires at least three distinct moments of time. Hence, the proposed inequality seems to open an additional experimental possibility to avoid the "contextuality loophole." Violation of the proposed equality and inequality is illustrated with the behavior of a pair of anticorrelated spins in an external magnetic field and also with the oscillations of flavor-entangled pairs of neutral pseudoscalar mesons.

Examining pediatric resuscitation education using simulation and scripted debriefing: a multicenter randomized trial.

PubMed

Cheng, Adam; Hunt, Elizabeth A; Donoghue, Aaron; Nelson-McMillan, Kristen; Nishisaki, Akira; Leflore, Judy; Eppich, Walter; Moyer, Mike; Brett-Fleegler, Marisa; Kleinman, Monica; Anderson, Jodee; Adler, Mark; Braga, Matthew; Kost, Susanne; Stryjewski, Glenn; Min, Steve; Podraza, John; Lopreiato, Joseph; Hamilton, Melinda Fiedor; Stone, Kimberly; Reid, Jennifer; Hopkins, Jeffrey; Manos, Jennifer; Duff, Jonathan; Richard, Matthew; Nadkarni, Vinay M

2013-06-01

Resuscitation training programs use simulation and debriefing as an educational modality with limited standardization of debriefing format and content. Our study attempted to address this issue by using a debriefing script to standardize debriefings. To determine whether use of a scripted debriefing by novice instructors and/or simulator physical realism affects knowledge and performance in simulated cardiopulmonary arrests. DESIGN Prospective, randomized, factorial study design. The study was conducted from 2008 to 2011 at 14 Examining Pediatric Resuscitation Education Using Simulation and Scripted Debriefing (EXPRESS) network simulation programs. Interprofessional health care teams participated in 2 simulated cardiopulmonary arrests, before and after debriefing. We randomized 97 participants (23 teams) to nonscripted low-realism; 93 participants (22 teams) to scripted low-realism; 103 participants (23 teams) to nonscripted high-realism; and 94 participants (22 teams) to scripted high-realism groups. INTERVENTION Participants were randomized to 1 of 4 arms: permutations of scripted vs nonscripted debriefing and high-realism vs low-realism simulators. Percentage difference (0%-100%) in multiple choice question (MCQ) test (individual scores), Behavioral Assessment Tool (BAT) (team leader performance), and the Clinical Performance Tool (CPT) (team performance) scores postintervention vs preintervention comparison (PPC). There was no significant difference at baseline in nonscripted vs scripted groups for MCQ (P = .87), BAT (P = .99), and CPT (P = .95) scores. Scripted debriefing showed greater improvement in knowledge (mean [95% CI] MCQ-PPC, 5.3% [4.1%-6.5%] vs 3.6% [2.3%-4.7%]; P = .04) and team leader behavioral performance (median [interquartile range (IQR)] BAT-PPC, 16% [7.4%-28.5%] vs 8% [0.2%-31.6%]; P = .03). Their improvement in clinical performance during simulated cardiopulmonary arrests was not significantly different (median [IQR] CPT-PPC, 7.9% [4

An assessment of the realism of digital human manikins used for simulation in ergonomics.

PubMed

Nérot, Agathe; Skalli, Wafa; Wang, Xuguang

2015-01-01

In this study, the accuracy of the joint centres of the manikins generated by RAMSIS and Human Builder (HB), two digital human modelling (DHM) systems widely used in industry for virtual ergonomics simulation, was investigated. Eighteen variously sized females and males were generated from external anthropometric dimensions and six joint centres (knee, hip and four spine joints) were compared with their anatomic locations obtained from the three-dimensional reconstructed bones from a low-dose X-ray system. Both RAMSIS and HB could correctly reproduce external anthropometric dimensions, while the estimation of internal joint centres location presented an average error of 27.6 mm for HB and 38.3 mm for RAMSIS. Differences between both manikins showed that a more realistic kinematic linkage led to better accuracy in joint location. This study opens the way to further research on the relationship between the external body geometry and internal skeleton in order to improve the realism of the internal skeleton of DHMs, especially for a biomechanical analysis requiring information of joint load and muscle force estimation. This study assessed two digital human modelling (DHM) systems widely used in industry for virtual ergonomics. Results support the need of a more realistic human modelling, especially for a biomechanical analysis and a standardisation of DHMs.

Entropic no-disturbance as a physical principle

NASA Astrophysics Data System (ADS)

Jia, Zhih-Ahn; Zhai, Rui; Yu, Bai-Chu; Wu, Yu-Chun; Guo, Guang-Can

2018-05-01

The celebrated Bell-Kochen-Specker no-go theorem asserts that quantum mechanics does not present the property of realism; the essence of the theorem is the lack of a joint probability distribution for some experiment settings. We exploit the information theoretic form of the theorem using information measure instead of probabilistic measure and indicate that quantum mechanics does not present such kind of entropic realism either. The entropic form of Gleason's no-disturbance principle is developed and characterized by the intersection of several entropic cones. Entropic contextuality and entropic nonlocality are investigated in depth in this framework as well. We show how one can construct monogamy relations using entropic cone and basic Shannon-type inequalities. The general criterion for several entropic tests to be monogamous is also developed; using the criterion, we demonstrate that entropic nonlocal correlations, entropic contextuality tests, and entropic nonlocality and entropic contextuality are monogamous. Finally, we analyze the entropic monogamy relations for the multiparty and many-test case, which may play a crucial role in quantum network communication.

The evolution of process-based hydrologic models: historical challenges and the collective quest for physical realism

NASA Astrophysics Data System (ADS)

Clark, Martyn P.; Bierkens, Marc F. P.; Samaniego, Luis; Woods, Ross A.; Uijlenhoet, Remko; Bennett, Katrina E.; Pauwels, Valentijn R. N.; Cai, Xitian; Wood, Andrew W.; Peters-Lidard, Christa D.

2017-07-01

The diversity in hydrologic models has historically led to great controversy on the correct approach to process-based hydrologic modeling, with debates centered on the adequacy of process parameterizations, data limitations and uncertainty, and computational constraints on model analysis. In this paper, we revisit key modeling challenges on requirements to (1) define suitable model equations, (2) define adequate model parameters, and (3) cope with limitations in computing power. We outline the historical modeling challenges, provide examples of modeling advances that address these challenges, and define outstanding research needs. We illustrate how modeling advances have been made by groups using models of different type and complexity, and we argue for the need to more effectively use our diversity of modeling approaches in order to advance our collective quest for physically realistic hydrologic models.

The evolution of process-based hydrologic models: historical challenges and the collective quest for physical realism

NASA Astrophysics Data System (ADS)

Clark, M. P.; Nijssen, B.; Wood, A.; Mizukami, N.; Newman, A. J.

2017-12-01

The diversity in hydrologic models has historically led to great controversy on the "correct" approach to process-based hydrologic modeling, with debates centered on the adequacy of process parameterizations, data limitations and uncertainty, and computational constraints on model analysis. In this paper, we revisit key modeling challenges on requirements to (1) define suitable model equations, (2) define adequate model parameters, and (3) cope with limitations in computing power. We outline the historical modeling challenges, provide examples of modeling advances that address these challenges, and define outstanding research needs. We illustrate how modeling advances have been made by groups using models of different type and complexity, and we argue for the need to more effectively use our diversity of modeling approaches in order to advance our collective quest for physically realistic hydrologic models.

The evolution of process-based hydrologic models: historical challenges and the collective quest for physical realism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, Martyn P.; Bierkens, Marc F. P.; Samaniego, Luis

The diversity in hydrologic models has historically led to great controversy on the correct approach to process-based hydrologic modeling, with debates centered on the adequacy of process parameterizations, data limitations and uncertainty, and computational constraints on model analysis. Here, we revisit key modeling challenges on requirements to (1) define suitable model equations, (2) define adequate model parameters, and (3) cope with limitations in computing power. We outline the historical modeling challenges, provide examples of modeling advances that address these challenges, and define outstanding research needs. We also illustrate how modeling advances have been made by groups using models of different type and complexity,more » and we argue for the need to more effectively use our diversity of modeling approaches in order to advance our collective quest for physically realistic hydrologic models.« less

The evolution of process-based hydrologic models: historical challenges and the collective quest for physical realism

DOE PAGES

Clark, Martyn P.; Bierkens, Marc F. P.; Samaniego, Luis; ...

2017-07-11

The diversity in hydrologic models has historically led to great controversy on the correct approach to process-based hydrologic modeling, with debates centered on the adequacy of process parameterizations, data limitations and uncertainty, and computational constraints on model analysis. Here, we revisit key modeling challenges on requirements to (1) define suitable model equations, (2) define adequate model parameters, and (3) cope with limitations in computing power. We outline the historical modeling challenges, provide examples of modeling advances that address these challenges, and define outstanding research needs. We also illustrate how modeling advances have been made by groups using models of different type and complexity,more » and we argue for the need to more effectively use our diversity of modeling approaches in order to advance our collective quest for physically realistic hydrologic models.« less

Carbohydrate Stereochemistry.

ERIC Educational Resources Information Center

Shallenberger, Robert S.; Wienen, Wanda J.

1989-01-01

Treats the development of general stereochemical principles in historical fashion. Discusses work by Pasteur, van't Hoff, and Le Bel. Considers sugars by configuration, anomeric forms, ring forms, and conformational isomers. Presents numerous diagrams and thorough explanations. (MVL)

The effect of different levels of realism of context learning on the prescribing competencies of medical students during the clinical clerkship in internal medicine: an exploratory study.

PubMed

Tichelaar, Jelle; van Kan, Coen; van Unen, Robert J; Schneider, Anton J; van Agtmael, Michiel A; de Vries, Theo P G M; Richir, Milan C

2015-02-01

The aim of this study is to evaluate the effect of different levels of realism of context learning on the prescribing competencies of medical students during the clinical clerkship in internal medicine. Between 2001 and 2007, 164 medical students took part in the prospective explorative study during their clinical clerkship in internal medicine at the VU University Medical Center, Amsterdam, The Netherlands. In a fixed order, each student had to formulate a treatment plan for a real patient in three situations of increasing realism: a minimal level (studying a patient record), medium level (preparing for a therapeutic consultation), and optimal level (preparing for and performing a therapeutic consultation with the patient). In comparison to studying a patient record (minimal context level), preparing a therapeutic consultation (medium context) improved four of the six steps of the WHO six-step plan. Preparing and performing a therapeutic consultation with a real patient (optimal context) further improved three essential prescribing competencies, namely checking for contraindications and interactions, prescription writing, and instructions to the patient. The results of this first explorative study suggest that enrichment of the learning context (responsibility for patient care) might be an important factor to improve the training of rational prescribing skills of medical students during their clinical clerkship in internal medicine. Clinical (pharmacology) teachers should be aware that seemingly small adaptations in the learning context of prescribing training during clinical clerkships (i.e., with or without involvement with and responsibility for patient care) may have relatively large impact on the development of prescribing competencies of our future doctors.

Effect of improving the realism of simulated clinical judgement tasks on nurses' overconfidence and underconfidence: evidence from a comparative confidence calibration analysis.

PubMed

Yang, Huiqin; Thompson, Carl; Bland, Martin

2012-12-01

Apparent overconfidence and underconfidence in clinicians making clinical judgements could be a feature of evaluative research designs that fail to accurately represent clinical environments. To test the effect of improved realism of clinical judgement tasks on confidence calibration performance of nurses and student nurses. A comparative confidence calibration analysis. The study was conducted in a large university of Northern England. Ninety-seven participants rated their confidence - using a scale that ranged from 0 (no confidence) to 100 (totally confident) on dichotomous clinical judgements of critical event risk. The judgements were in response to 25 paper-based and 25 higher fidelity scenarios using a computerised patient simulator and clinical equipment. Scenarios, and judgement criteria of 'correctness', were generated from real patient cases. Using a series of calibration measures (calibration, resolution and over/underconfidence), participants' confidence was calibrated against the proportion of correct judgements. The calibration measures generated by the paper-based and high fidelity clinical simulation conditions were compared. Participants made significantly less accurate clinical judgements of risk in the high fidelity clinical simulations compared to the paper simulations (P=0.0002). They were significantly less confident in high fidelity clinical simulations than paper simulations (P=0.03). However, there was no significant difference of over/underconfidence for participants between the two simulated settings (P=0.06). Participants were no better calibrated in the high fidelity clinical simulations than paper simulations, P=0.85. Likewise, participants had no better ability of discriminating correct judgements from incorrect judgements as measured by the resolution statistic in high fidelity clinical simulations than paper simulations, P=0.76. Improving the realism of simulated judgement tasks led to reduced confidence and judgement accuracy in

Synthetic cathinones and stereochemistry: S enantiomer of mephedrone reduces anxiety- and depressant-like effects in cocaine- or MDPV-abstinent rats.

PubMed

Philogene-Khalid, Helene L; Hicks, Callum; Reitz, Allen B; Liu-Chen, Lee-Yuan; Rawls, Scott M

2017-09-01

The neuropharmacological profile of the synthetic cathinone mephedrone (MEPH) is influenced by stereochemistry. Both MEPH enantiomers are monoamine transporter substrates, but R-MEPH is primarily responsible for rewarding effects of MEPH as it produces greater locomotor activation and intracranial self-stimulation than S-MEPH. S-MEPH is a 50-fold more potent 5-HT releaser than R-MEPH and does not place preference in rats. MEPH is also structurally similar to the cathinone derivative bupropion, an antidepressant and smoking cessation medication, suggesting MEPH has therapeutic and addictive properties. We tested the hypothesis that S-MEPH reduces anxiety- and depression-like behaviors in rats withdrawn from chronic cocaine or methylenedioxypyrovalerone (MDPV) using the elevated plus maze (EPM) and forced swim test (FST), respectively. Rats were tested 48-h after a binge-like paradigm (3×/day for 10days in 1-h intervals) of cocaine (10mg/kg), MDPV (1mg/kg) or saline. In vitro studies assessed the receptor binding and activity of S-MEPH. Rats withdrawn from chronic cocaine or MDPV displayed an increase in anxiety- and depression-like behaviors that was antagonized by treatment with S-MEPH (10, 30mg/kg). S-MEPH displayed affinity, but not agonist activity, for 5-HT 2 receptors (2A-2C) and showed negligible affinity for dopaminergic, adrenergic and nicotinic receptors. S-MEPH attenuated withdrawal behaviors following chronic cocaine or MDPV, perhaps through 5-HT release and/or 5-HT 2 receptor interactions. The present data suggest S-MEPH may be a possible structural and pharmacological template to develop maintenance therapy for acute anxiety and depression during early withdrawal from psychostimulant abuse. Copyright © 2017 Elsevier B.V. All rights reserved.

Physics based performance model of a UV missile seeker

NASA Astrophysics Data System (ADS)

James, I.

2017-10-01

Electro-optically (EO) guided surface to air missiles (SAM) have developed to use Ultraviolet (UV) wavebands supplementary to the more common Infrared (IR) wavebands. Missiles such as the US Stinger have been around for some time, these have been joined recently by Chinese FN-16 and Russian SA-29 (Verba) and there is a much higher potential proliferation risk. The purpose of this paper is to introduce a first-principles, physics based, model of a typical seeker arrangement. The model is constructed from various calculations that aim to characterise the physical effects that will affect the performance of the system. Data has been gathered from a number of sources to provide realism to the variables within the model. It will be demonstrated that many of the variables have the power to dramatically alter the performance of the system as a whole. Further, data will be shown to illustrate the expected performance of a typical UV detector within a SAM in detection range against a variety of target sizes. The trend for the detection range against aircraft size and skin reflectivity will be shown to be non-linear, this should have been expected owing to the exponential decay of a signal through atmosphere. Future work will validate the performance of the model against real world performance data for cameras (when this is available) to ensure that it is operates within acceptable errors.

Realism without truth: a review of Giere's science without laws and scientific perspectivism.

PubMed

Hackenberg, Timothy D

2009-05-01

An increasingly popular view among philosophers of science is that of science as action-as the collective activity of scientists working in socially-coordinated communities. Scientists are seen not as dispassionate pursuers of Truth, but as active participants in a social enterprise, and science is viewed on a continuum with other human activities. When taken to an extreme, the science-as-social-process view can be taken to imply that science is no different from any other human activity, and therefore can make no privileged claims about its knowledge of the world. Such extreme views are normally contrasted with equally extreme views of classical science, as uncovering Universal Truth. In Science Without Laws and Scientific Perspectivism, Giere outlines an approach to understanding science that finds a middle ground between these extremes. He acknowledges that science occurs in a social and historical context, and that scientific models are constructions designed and created to serve human ends. At the same time, however, scientific models correspond to parts of the world in ways that can legitimately be termed objective. Giere's position, perspectival realism, shares important common ground with Skinner's writings on science, some of which are explored in this review. Perhaps most fundamentally, Giere shares with Skinner the view that science itself is amenable to scientific inquiry: scientific principles can and should be brought to bear on the process of science. The two approaches offer different but complementary perspectives on the nature of science, both of which are needed in a comprehensive understanding of science.

REALISM WITHOUT TRUTH: A REVIEW OF GIERE'S SCIENCE WITHOUT LAWS AND SCIENTIFIC PERSPECTIVISM

PubMed Central

Hackenberg, Timothy D

2009-01-01

An increasingly popular view among philosophers of science is that of science as action—as the collective activity of scientists working in socially-coordinated communities. Scientists are seen not as dispassionate pursuers of Truth, but as active participants in a social enterprise, and science is viewed on a continuum with other human activities. When taken to an extreme, the science-as-social-process view can be taken to imply that science is no different from any other human activity, and therefore can make no privileged claims about its knowledge of the world. Such extreme views are normally contrasted with equally extreme views of classical science, as uncovering Universal Truth. In Science Without Laws and Scientific Perspectivism, Giere outlines an approach to understanding science that finds a middle ground between these extremes. He acknowledges that science occurs in a social and historical context, and that scientific models are constructions designed and created to serve human ends. At the same time, however, scientific models correspond to parts of the world in ways that can legitimately be termed objective. Giere's position, perspectival realism, shares important common ground with Skinner's writings on science, some of which are explored in this review. Perhaps most fundamentally, Giere shares with Skinner the view that science itself is amenable to scientific inquiry: scientific principles can and should be brought to bear on the process of science. The two approaches offer different but complementary perspectives on the nature of science, both of which are needed in a comprehensive understanding of science. PMID:19949495

Recalibrating disease parameters for increasing realism in modeling epidemics in closed settings.

PubMed

Bioglio, Livio; Génois, Mathieu; Vestergaard, Christian L; Poletto, Chiara; Barrat, Alain; Colizza, Vittoria

2016-11-14

The homogeneous mixing assumption is widely adopted in epidemic modelling for its parsimony and represents the building block of more complex approaches, including very detailed agent-based models. The latter assume homogeneous mixing within schools, workplaces and households, mostly for the lack of detailed information on human contact behaviour within these settings. The recent data availability on high-resolution face-to-face interactions makes it now possible to assess the goodness of this simplified scheme in reproducing relevant aspects of the infection dynamics. We consider empirical contact networks gathered in different contexts, as well as synthetic data obtained through realistic models of contacts in structured populations. We perform stochastic spreading simulations on these contact networks and in populations of the same size under a homogeneous mixing hypothesis. We adjust the epidemiological parameters of the latter in order to fit the prevalence curve of the contact epidemic model. We quantify the agreement by comparing epidemic peak times, peak values, and epidemic sizes. Good approximations of the peak times and peak values are obtained with the homogeneous mixing approach, with a median relative difference smaller than 20 % in all cases investigated. Accuracy in reproducing the peak time depends on the setting under study, while for the peak value it is independent of the setting. Recalibration is found to be linear in the epidemic parameters used in the contact data simulations, showing changes across empirical settings but robustness across groups and population sizes. An adequate rescaling of the epidemiological parameters can yield a good agreement between the epidemic curves obtained with a real contact network and a homogeneous mixing approach in a population of the same size. The use of such recalibrated homogeneous mixing approximations would enhance the accuracy and realism of agent-based simulations and limit the intrinsic biases of

Realism and Perspectivism: a Reevaluation of Rival Theories of Spatial Vision.

NASA Astrophysics Data System (ADS)

Thro, E. Broydrick

1990-01-01

My study reevaluates two theories of human space perception, a trigonometric surveying theory I call perspectivism and a "scene recognition" theory I call realism. Realists believe that retinal image geometry can supply no unambiguous information about an object's size and distance--and that, as a result, viewers can locate objects in space only by making discretionary interpretations based on familiar experience of object types. Perspectivists, in contrast, think viewers can disambiguate object sizes/distances on the basis of retinal image information alone. More specifically, they believe the eye responds to perspective image geometry with an automatic trigonometric calculation that not only fixes the directions and shapes, but also roughly fixes the sizes and distances of scene elements in space. Today this surveyor theory has been largely superceded by the realist approach, because most vision scientists believe retinal image geometry is ambiguous about the scale of space. However, I show that there is a considerable body of neglected evidence, both past and present, tending to call this scale ambiguity claim into question. I maintain that this evidence against scale ambiguity could hardly be more important, if one considers its subversive implications for the scene recognition theory that is not only today's reigning approach to spatial vision, but also the foundation for computer scientists' efforts to create space-perceiving robots. If viewers were deemed to be capable of automatic surveying calculations, the discretionary scene recognition theory would lose its main justification. Clearly, it would be difficult for realists to maintain that we viewers rely on scene recognition for space perception in spite of our ability to survey. And in reality, as I show, the surveyor theory does a much better job of describing the everyday space we viewers actually see--a space featuring stable, unambiguous relationships among scene elements, and a single horizon and

DNA-fiber EPR investigation of the influence of amino-terminal residue stereochemistry on the DNA binding orientation of Cu(II)•Gly-Gly-His-derived metallopeptides

PubMed Central

Hamada, Hirokazu; Abe, Yuko; Nagane, Ryoichi; Fang, Ya-Yin; Lewis, Mark A.; Long, Eric C.; Chikira, Makoto

2007-01-01

DNA fiber EPR was used to investigate the DNA binding stabilities and orientations of Cu(II)•Gly-Gly-His-derived metallopeptides containing d- vs. l-amino acid substitutions in the first peptide position. This examination included studies of Cu(II)•d-Arg-Gly-His and Cu(II)•d-Lys-Gly-His for comparison to metallopeptides containing l-Arg/Lys substitutions, and also the diastereoisomeric pairs Cu(II)•d/l-Pro-Gly-His and Cu(II)•d/l-Pro-Lys-His. Results indicated that l-Arg/Lys to d-Arg/Lys substitutions considerably randomized the orientation of the metallopeptides on DNA whereas the replacement of l-Pro by d-Pro in Cu(II)•l-Pro-Gly-His caused a decrease in randomness. The difference in the extent of randomness of d- vs. l-Pro-Gly-His complexes was diminished through the substitution of Gly for Lys in the middle peptide position, supporting the notion that the ε-amino group of Lys triggered further randomization, likely through hydrogen bonding or electrostatic interactions that disrupt binding of the metallopeptide equatorial plane and the DNA. The relationship between the stereochemistry of amino acid residues and the binding and reaction of M(II)•Xaa-Xaa’-His metallopeptides with DNA are also discussed. PMID:17706784

The effectiveness of physical models in teaching anatomy: a meta-analysis of comparative studies.

PubMed

Yammine, Kaissar; Violato, Claudio

2016-10-01

There are various educational methods used in anatomy teaching. While three dimensional (3D) visualization technologies are gaining ground due to their ever-increasing realism, reports investigating physical models as a low-cost 3D traditional method are still the subject of considerable interest. The aim of this meta-analysis is to quantitatively assess the effectiveness of such models based on comparative studies. Eight studies (7 randomized trials; 1 quasi-experimental) including 16 comparison arms and 820 learners met the inclusion criteria. Primary outcomes were defined as factual, spatial and overall percentage scores. The meta-analytical results are: educational methods using physical models yielded significantly better results when compared to all other educational methods for the overall knowledge outcome (p < 0.001) and for spatial knowledge acquisition (p < 0.001). Significantly better results were also found with regard to the long-retention knowledge outcome (p < 0.01). No significance was found for the factual knowledge acquisition outcome. The evidence in the present systematic review was found to have high internal validity and at least an acceptable strength. In conclusion, physical anatomical models offer a promising tool for teaching gross anatomy in 3D representation due to their easy accessibility and educational effectiveness. Such models could be a practical tool to bring up the learners' level of gross anatomy knowledge at low cost.

Interactive physically-based sound simulation

NASA Astrophysics Data System (ADS)

Raghuvanshi, Nikunj

The realization of interactive, immersive virtual worlds requires the ability to present a realistic audio experience that convincingly compliments their visual rendering. Physical simulation is a natural way to achieve such realism, enabling deeply immersive virtual worlds. However, physically-based sound simulation is very computationally expensive owing to the high-frequency, transient oscillations underlying audible sounds. The increasing computational power of desktop computers has served to reduce the gap between required and available computation, and it has become possible to bridge this gap further by using a combination of algorithmic improvements that exploit the physical, as well as perceptual properties of audible sounds. My thesis is a step in this direction. My dissertation concentrates on developing real-time techniques for both sub-problems of sound simulation: synthesis and propagation. Sound synthesis is concerned with generating the sounds produced by objects due to elastic surface vibrations upon interaction with the environment, such as collisions. I present novel techniques that exploit human auditory perception to simulate scenes with hundreds of sounding objects undergoing impact and rolling in real time. Sound propagation is the complementary problem of modeling the high-order scattering and diffraction of sound in an environment as it travels from source to listener. I discuss my work on a novel numerical acoustic simulator (ARD) that is hundred times faster and consumes ten times less memory than a high-accuracy finite-difference technique, allowing acoustic simulations on previously-intractable spaces, such as a cathedral, on a desktop computer. Lastly, I present my work on interactive sound propagation that leverages my ARD simulator to render the acoustics of arbitrary static scenes for multiple moving sources and listener in real time, while accounting for scene-dependent effects such as low-pass filtering and smooth attenuation

ns2np4 (n = 4, 5) lone pair triplets whirling in M*F2E3 (M* = Kr, Xe): Stereochemistry and ab initio analyses

NASA Astrophysics Data System (ADS)

Galy, Jean; Matar, Samir F.

2017-02-01

The stereochemistry of ns2np4 (n = 4, 5) lone pair LP characterizing noble gas Kr and Xe (labeled M*) in M*F2 difluorides is examined within coherent crystal chemistry and ab initio visualizations. M*2+ in such oxidation state brings three lone pairs (E) and difluorides are formulated M*F2E3. The analyses use electron localization function (ELF) obtained within density functional theory calculations showing the development of the LP triplets whirling {E3} quantified in the relevant chemical systems. Detailed ELF data analyses allowed showing that in α KrF2E3 and isostructural XeF2E3 difluorides the three E electronic clouds merge or hybridize into a torus and adopt a perfect gyration circle with an elliptical section, while in β KrF2 the network architecture deforms the whole torus into an ellipsoid shape. Original precise metrics are provided for the torus in the different compounds under study. In KrF2 the geometric changes upon β → α phase transition is schematized and mechanisms for the transformation with temperature or pressure are proposed. The results are further highlighted by electronic band structure calculations which show similar features of equal band gaps of 3 eV in both α and β KrF2 and a reorganization of frontier orbitals due to the different orientations of the F-Kr-F linear molecule in the two tetragonal structures.

Peer role-play and standardised patients in communication training: a comparative study on the student perspective on acceptability, realism, and perceived effect

PubMed Central

2010-01-01

Background To assess the student perspective on acceptability, realism, and perceived effect of communication training with peer role play (RP) and standardised patients (SP). Methods 69 prefinal year students from a large German medical faculty were randomly assigned to one of two groups receiving communication training with RP (N = 34) or SP (N = 35) in the course of their paediatric rotation. In both groups, training addressed major medical and communication problems encountered in the exploration and counselling of parents of sick children. Acceptability and realism of the training as well as perceived effects and applicability for future parent-physician encounters were assessed using six-point Likert scales. Results Both forms of training were highly accepted (RP 5.32 ± .41, SP 5.51 ± .44, n.s.; 6 = very good, 1 = very poor) and perceived to be highly realistic (RP 5.60 ± .38, SP 5.53 ± .36, n.s.; 6 = highly realistic, 1 = unrealistic). Regarding perceived effects, participation was seen to be significantly more worthwhile in the SP group (RP 5.17 ± .37, SP 5.50 ± .43; p < .003; 6 = totally agree, 1 = don't agree at all). Both training methods were perceived as useful for training communication skills (RP 5.01 ± .68, SP 5.34 ± .47; 6 = totally agree; 1 = don't agree at all) and were considered to be moderately applicable for future parent-physician encounters (RP 4.29 ± 1.08, SP 5.00 ± .89; 6 = well prepared, 1 = unprepared), with usefulness and applicability both being rated higher in the SP group (p < .032 and p < .009). Conclusions RP and SP represent comparably valuable tools for the training of specific communication skills from the student perspective. Both provide highly realistic training scenarios and warrant inclusion in medical curricula. Given the expense of SP, deciding which method to employ should be carefully weighed up. From the perspective of the students in our study, SP were seen as a more useful and more applicable tool than RP

Modification of Obstetric Emergency Simulation Scenarios for Realism in a Home-Birth Setting.

PubMed

Komorowski, Janelle; Andrighetti, Tia; Benton, Melissa

2017-01-01

Clinical competency and clear communication are essential for intrapartum care providers who encounter high-stakes, low-frequency emergencies. The challenge for these providers is to maintain infrequently used skills. The challenge is even more significant for midwives who manage births at home and who, due to low practice volume and low-risk clientele, may rarely encounter an emergency. In addition, access to team simulation may be limited for home-birth midwives. This project modified existing validated obstetric simulation scenarios for a home-birth setting. Twelve certified professional midwives (CPMs) in active home-birth practice participated in shoulder dystocia and postpartum hemorrhage simulations. The simulations were staged to resemble home-birth settings, supplies, and personnel. Fidelity (realism) of the simulations was assessed with the Simulation Design Scale, and satisfaction and self-confidence were assessed with the Student Satisfaction and Self-Confidence in Learning Scale. Both utilized a 5-point Likert scale, with higher scores suggesting greater levels of fidelity, participant satisfaction, and self-confidence. Simulation Design Scale scores indicated participants agreed fidelity was achieved for the home-birth setting, while scores on the Student Satisfaction and Self-Confidence in Learning indicated high levels of participant satisfaction and self-confidence. If offered without modification, simulation scenarios designed for use in hospitals may lose fidelity for home-birth midwives, particularly in the environmental and psychological components. Simulation is standard of care in most settings, an excellent vehicle for maintaining skills, and some evidence suggests it results in improved perinatal outcomes. Additional study is needed in this area to support home-birth providers in maintaining skills. This pilot study suggests that simulation scenarios intended for hospital use can be successfully adapted to the home-birth setting. © 2016 by

Assessment of Irrigation Physics in a Land Surface Modeling Framework Using Non-Traditional and Human-Practice Datasets

NASA Technical Reports Server (NTRS)

Lawston, Patricia M.; Santanello, Joseph A.; Rodell, Matthew; Franz, Trenton E.

2017-01-01

Irrigation increases soil moisture, which in turn controls water and energy fluxes from the land surface to the10 planetary boundary layer and determines plant stress and productivity. Therefore, developing a realistic representation of irrigation is critical to understanding land-atmosphere interactions in agricultural areas. Irrigation parameterizations are becoming more common in land surface models and are growing in sophistication, but there is difficulty in assessing the realism of these schemes, due to limited observations (e.g., soil moisture, evapotranspiration) and scant reporting of irrigation timing and quantity. This study uses the Noah land surface model run at high resolution within NASAs Land15 Information System to assess the physics of a sprinkler irrigation simulation scheme and model sensitivity to choice of irrigation intensity and greenness fraction datasets over a small, high resolution domain in Nebraska. Differences between experiments are small at the interannual scale but become more apparent at seasonal and daily time scales. In addition, this study uses point and gridded soil moisture observations from fixed and roving Cosmic Ray Neutron Probes and co-located human practice data to evaluate the realism of irrigation amounts and soil moisture impacts simulated by the model. Results20 show that field-scale heterogeneity resulting from the individual actions of farmers is not captured by the model and the amount of irrigation applied by the model exceeds that applied at the two irrigated fields. However, the seasonal timing of irrigation and soil moisture contrasts between irrigated and non-irrigated areas are simulated well by the model. Overall, the results underscore the necessity of both high-quality meteorological forcing data and proper representation of irrigation foraccurate simulation of water and energy states and fluxes over cropland.

Stereochemistry and solvent role in protein folding: nuclear magnetic resonance and molecular dynamics studies of poly-L and alternating-L,D homopolypeptides in dimethyl sulfoxide.

PubMed

Srivastava, Kinshuk Raj; Kumar, Anil; Goyal, Bhupesh; Durani, Susheel

2011-05-26

The competing interactions folding and unfolding protein structure remain obscure. Using homopolypeptides, we ask if poly-L structure may have a role. We mutate the structure to alternating-L,D stereochemistry and substitute water as the fold-promoting solvent with methanol and dimethyl sulfoxide (DMSO) as the fold-denaturing solvents. Circular dichroism and molecular dynamics established previously that, while both isomers were folded in water, the poly-L isomer was unfolded and alternating-L,D isomer folded in methanol. Nuclear magnetic resonance and molecular dynamics establish now that both isomers are unfolded in DMSO. We calculated energetics of folding-unfolding equilibrium with water and methanol as solvents. We have now calculated interactions of unfolded polypeptide structures with DMSO as solvent. Methanol was found to unfold and water fold poly-L structure as a dielectric. DMSO has now been found to unfold both poly-L and alternating-L,D structures by strong solvation of peptides to disrupt their hydrogen bonds. Accordingly, we propose that while linked peptides fold protein structure with hydrogen bonds they unfold the structure electrostatically due to the stereochemical effect of the poly-L structure. Protein folding to ordering of peptide hydrogen bonds with water as canonical solvent may thus involve two specific and independent solvent effects-one, strong screening of electrostatics of poly-L linked peptides, and two, weak dipolar solvation of peptides. Correspondingly, protein denaturation may involve two independent solvent effects-one, weak dielectric to unfold poly-L structure electrostatically, and two, strong polarity to disrupt peptide hydrogen bonds by solvation of peptides.

Shock treatment: using immersive digital realism to restage and re-examine milgram's 'obedience to authority' research.

PubMed

Haslam, S Alexander; Reicher, Stephen D; Millard, Kathryn

2015-01-01

Attempts to revisit Milgram's 'Obedience to Authority' (OtA) paradigm present serious ethical challenges. In recent years new paradigms have been developed to circumvent these challenges but none involve using Milgram's own procedures and asking naïve participants to deliver the maximum level of shock. This was achieved in the present research by using Immersive Digital Realism (IDR) to revisit the OtA paradigm. IDR is a dramatic method that involves a director collaborating with professional actors to develop characters, the strategic withholding of contextual information, and immersion in a real-world environment. 14 actors took part in an IDR study in which they were assigned to conditions that restaged Milgrams's New Baseline ('Coronary') condition and four other variants. Post-experimental interviews also assessed participants' identification with Experimenter and Learner. Participants' behaviour closely resembled that observed in Milgram's original research. In particular, this was evidenced by (a) all being willing to administer shocks greater than 150 volts, (b) near-universal refusal to continue after being told by the Experimenter that "you have no other choice, you must continue" (Milgram's fourth prod and the one most resembling an order), and (c) a strong correlation between the maximum level of shock that participants administered and the mean maximum shock delivered in the corresponding variant in Milgram's own research. Consistent with an engaged follower account, relative identification with the Experimenter (vs. the Learner) was also a good predictor of the maximum shock that participants administered.

Significant-Loophole-Free Test of Bell's Theorem with Entangled Photons.

PubMed

Giustina, Marissa; Versteegh, Marijn A M; Wengerowsky, Sören; Handsteiner, Johannes; Hochrainer, Armin; Phelan, Kevin; Steinlechner, Fabian; Kofler, Johannes; Larsson, Jan-Åke; Abellán, Carlos; Amaya, Waldimar; Pruneri, Valerio; Mitchell, Morgan W; Beyer, Jörn; Gerrits, Thomas; Lita, Adriana E; Shalm, Lynden K; Nam, Sae Woo; Scheidl, Thomas; Ursin, Rupert; Wittmann, Bernhard; Zeilinger, Anton

2015-12-18

Local realism is the worldview in which physical properties of objects exist independently of measurement and where physical influences cannot travel faster than the speed of light. Bell's theorem states that this worldview is incompatible with the predictions of quantum mechanics, as is expressed in Bell's inequalities. Previous experiments convincingly supported the quantum predictions. Yet, every experiment requires assumptions that provide loopholes for a local realist explanation. Here, we report a Bell test that closes the most significant of these loopholes simultaneously. Using a well-optimized source of entangled photons, rapid setting generation, and highly efficient superconducting detectors, we observe a violation of a Bell inequality with high statistical significance. The purely statistical probability of our results to occur under local realism does not exceed 3.74×10^{-31}, corresponding to an 11.5 standard deviation effect.

Biosynthesis of 4-aminoheptose 2-epimers, core structural components of the septacidins and spicamycins

USDA-ARS?s Scientific Manuscript database

Septacidins and spicamycins are acylated 4-aminoheptosyl-ß-N-glycosides produced by Streptomyces fimbriatus and S. alanosinicus, respectively. Their structures are highly conserved, but differ in the stereochemistry of the 4-aminoheptosyl residues. The origin of this stereochemistry is unknown, but ...

Dynamic and fluid-structure interaction simulations of bioprosthetic heart valves using parametric design with T-splines and Fung-type material models

NASA Astrophysics Data System (ADS)

Hsu, Ming-Chen; Kamensky, David; Xu, Fei; Kiendl, Josef; Wang, Chenglong; Wu, Michael C. H.; Mineroff, Joshua; Reali, Alessandro; Bazilevs, Yuri; Sacks, Michael S.

2015-06-01

This paper builds on a recently developed immersogeometric fluid-structure interaction (FSI) methodology for bioprosthetic heart valve (BHV) modeling and simulation. It enhances the proposed framework in the areas of geometry design and constitutive modeling. With these enhancements, BHV FSI simulations may be performed with greater levels of automation, robustness and physical realism. In addition, the paper presents a comparison between FSI analysis and standalone structural dynamics simulation driven by prescribed transvalvular pressure, the latter being a more common modeling choice for this class of problems. The FSI computation achieved better physiological realism in predicting the valve leaflet deformation than its standalone structural dynamics counterpart.

Dynamic and fluid–structure interaction simulations of bioprosthetic heart valves using parametric design with T-splines and Fung-type material models

PubMed Central

Kamensky, David; Xu, Fei; Kiendl, Josef; Wang, Chenglong; Wu, Michael C. H.; Mineroff, Joshua; Reali, Alessandro; Bazilevs, Yuri; Sacks, Michael S.

2015-01-01

This paper builds on a recently developed immersogeometric fluid–structure interaction (FSI) methodology for bioprosthetic heart valve (BHV) modeling and simulation. It enhances the proposed framework in the areas of geometry design and constitutive modeling. With these enhancements, BHV FSI simulations may be performed with greater levels of automation, robustness and physical realism. In addition, the paper presents a comparison between FSI analysis and standalone structural dynamics simulation driven by prescribed transvalvular pressure, the latter being a more common modeling choice for this class of problems. The FSI computation achieved better physiological realism in predicting the valve leaflet deformation than its standalone structural dynamics counterpart. PMID:26392645

Realism in the Realized Popper's Experiment

NASA Astrophysics Data System (ADS)

Hunter, Geoffrey

2002-12-01

The realization of Karl Popper's EPR-like experiment by Shih and Kim (published 1999) produced the result that Popper hoped for: no ``action at a distance'' on one photon of an entangled pair when a measurement is made on the other photon. This experimental result is interpretable in local realistic terms: each photon has a definite position and transverse momentum most of the time; the position measurement on one photon (localization within a slit) disturbs the transverse momentum of that photon in a non-predictable way in accordance with the uncertainty principle; however, there is no effect on the other photon (the photon that is not in a slit) no action at a distance. The position measurement (localization within a slit) of the one photon destroys the coherence (entanglement) between the photons; i.e. decoherence occurs. This realistic (albeit retrodictive) interpretation of the Shih-Kim realization of what Popper called his ``crucial experiment'' is in accord with Bohr's original concept of the nature of the uncertainty principle, as being an inevitable effect of the disturbance of the measured system by the measuring apparatus. In this experiment the impact parameter of an incident photon with the centerline of the slit is an uncontrollable parameter of each individual photon scattering event; this impact parameter is variable for every incident photon, the variations being a statistical aspect of the beam of photons produced by the experimental arrangement. These experimental results are also in accord with the proposition of Einstein, Podolski and Rosen's 1935 paper: that quantum mechanics provides only a statistical, physically incomplete, theory of microscopic physical processes, for the quantum mechanical description of the experiment does not describe or explain the individual photon scattering events that are actually observed; the angle by which an individual photon is scattered is not predictable, because the photon's impact parameter with the

Children's Interpretations of Computer-Animated Dinosaurs in Live Theatre: "Dinosaurus".

ERIC Educational Resources Information Center

Klein, Jeanne M.

To explore media theories of perceived reality regarding factuality, social, and physical realism, and "videocy" (or theatrical spectacle), 32 children in first, third, and fifth grades were individually interviewed after attending a production of "Dinosaurus" which included computer-animated dinosaurs. Contrary to beliefs that…

Non Kolmogorov Probability Models Outside Quantum Mechanics

NASA Astrophysics Data System (ADS)

Accardi, Luigi

2009-03-01

This paper is devoted to analysis of main conceptual problems in the interpretation of QM: reality, locality, determinism, physical state, Heisenberg principle, "deterministic" and "exact" theories, laws of chance, notion of event, statistical invariants, adaptive realism, EPR correlations and, finally, the EPR-chameleon experiment.

The Problem of Representation and Experience in Quantum Mechanics

NASA Astrophysics Data System (ADS)

Ronde, Christian De

2014-03-01

In this paper we discuss the problem of representation and experience in quantum mechanics. We analyze the importance of metaphysics in physical thought and its relation to empiricism and analytic philosophy. We argue against both instrumentalism and scientific realism and claim that both perspectives tend to bypass the problem of representation and justify a "common sense" type experience. Finally, we present our expressionist conception of physics.

Modeling and Reality in Early Twentieth-Century Physics

NASA Astrophysics Data System (ADS)

Seth, Suman

2011-04-01

Towards the end of 1913, Arnold Sommerfeld, Professor of theoretical physics at Munich University, sent a letter of congratulations to a young Niels Bohr. The Dane's now-classic trilogy of papers, which coupled Rutherford's conception of the atom with a ``planetary'' configuration of electrons, had just appeared. Sommerfeld saw the calculation of the Rydberg constant as a singular triumph and immediately spotted an opportunity to try to explain the Zeeman effect. Yet he also sounded a note of caution, confessing that he remained ``somewhat skeptical'' of atomic models in general. In this, of course, he was hardly alone. Bohr's atom was a particularly egregious example of a peculiar model, one requiring what even its creator considered ``horrid assumptions.'' Nonetheless, success bred conviction. Expanding upon Bohr's original ideas, Sommerfeld soon produced the so-called ``Bohr-Sommerfeld quantization conditions,'' using them to calculate a myriad of results. Experimental evidence, Sommerfeld argued in 1915, showed that quantised electron-paths ``correspond exactly to reality'' and possess ``real existence.'' This kind of realism would not, of course, last long. In 1925, Werner Heisenberg (earlier a student of Sommerfeld's) made scepticism about the details of the Bohr model into a methodological dictum, one later enshrined in the ``Copenhagen interpretation'' of quantum mechanics. This paper uses Sommerfeld's work from the turn of the twentieth century to the mid-1920s as a window onto a landscape involving multiple contestations over the legitimacy of atomic modelling. The surprise that greeted Heisenberg's and others' phenomenological insistences, we will see, can only be understood with reference to what should be considered a ``realist interlude'' in the history of twentieth century atomic physics, one inspired by the astonishing successes of Rutherford's and Bohr's imaginings.

The Value of Measurement for Development of Nursing Knowledge:Underlying Philosophy, Contributions and Critiques.

PubMed

Durepos, Pamela; Orr, Elizabeth; Ploeg, Jenny; Kaasalainen, Sharon

2018-06-26

A philosophical discussion of constructive realism and measurement in the development of nursing knowledge is presented. Through Carper's four patterns of knowing, nurses come to know a person holistically. However, measurement as a source for nursing knowledge has been criticized for underlying positivism and reductionist approach to exploring reality. Which seems mal-alignment with person-centered care. Discussion paper. Constructive realism bridges positivism and constructivism, facilitating the measurement of physical and psychological phenomena. Reduction of complex phenomena and theoretical constructs into measurable properties is essential to building nursing's empiric knowledge and facilitates (rather than inhibits) person-knowing. Nurses should consider constructive realism as a philosophy to underpin their practice. This philosophy supports measurement as a primary method of inquiry in nursing research and clinical practice. Nurses can carefully select, and purposefully integrate, measurement tools with other methods of inquiry (such as qualitative research methods) to demonstrate the usefulness of nursing interventions and highlight nursing as a science. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Impact of model structure on flow simulation and hydrological realism: from a lumped to a semi-distributed approach

NASA Astrophysics Data System (ADS)

Garavaglia, Federico; Le Lay, Matthieu; Gottardi, Fréderic; Garçon, Rémy; Gailhard, Joël; Paquet, Emmanuel; Mathevet, Thibault

2017-08-01

Model intercomparison experiments are widely used to investigate and improve hydrological model performance. However, a study based only on runoff simulation is not sufficient to discriminate between different model structures. Hence, there is a need to improve hydrological models for specific streamflow signatures (e.g., low and high flow) and multi-variable predictions (e.g., soil moisture, snow and groundwater). This study assesses the impact of model structure on flow simulation and hydrological realism using three versions of a hydrological model called MORDOR: the historical lumped structure and a revisited formulation available in both lumped and semi-distributed structures. In particular, the main goal of this paper is to investigate the relative impact of model equations and spatial discretization on flow simulation, snowpack representation and evapotranspiration estimation. Comparison of the models is based on an extensive dataset composed of 50 catchments located in French mountainous regions. The evaluation framework is founded on a multi-criterion split-sample strategy. All models were calibrated using an automatic optimization method based on an efficient genetic algorithm. The evaluation framework is enriched by the assessment of snow and evapotranspiration modeling against in situ and satellite data. The results showed that the new model formulations perform significantly better than the initial one in terms of the various streamflow signatures, snow and evapotranspiration predictions. The semi-distributed approach provides better calibration-validation performance for the snow cover area, snow water equivalent and runoff simulation, especially for nival catchments.

A Pauson-Khand approach to the synthesis of ingenol.

PubMed

Winkler, Jeffrey D; Lee, Esther C Y; Nevels, LaToya I

2005-04-14

[reaction: see text] Pauson-Khand cyclization of dioxanone photoadduct 21 leads to the formation of a single product in good yield. However, retro-aldol fragmentation of the pentacyclic cyclopentenone 22 leads to the formation of 23, with cis C-8/C-10 intrabridgehead stereochemistry, unlike the target compound ingenol 1, which possesses C-8/C-10 trans intrabridgehead stereochemistry.

Theonellapeptolide IIIe, a new cyclic peptolide from the New Zealand deep water sponge, Lamellomorpha strongylata.

PubMed

Li, S; Dumdei, E J; Blunt, J W; Munro, M H; Robinson, W T; Pannell, L K

1998-06-26

The structure, stereochemistry, and conformation of theonellapeptolide IIIe (1), a new 36-membered ring cyclic peptolide from the New Zealand deep-water sponge Lamellomorpha strongylata, is described. The sequence of the cytotoxic peptolide was determined through a combination of NMR and MS-MS techniques and confirmed by X-ray crystal structure analysis, which, with chiral HPLC, established the absolute stereochemistry.

Shock Treatment: Using Immersive Digital Realism to Restage and Re-examine Milgram’s ‘Obedience to Authority’ Research

PubMed Central

Haslam, S. Alexander; Reicher, Stephen D.; Millard, Kathryn

2015-01-01

Attempts to revisit Milgram’s ‘Obedience to Authority’ (OtA) paradigm present serious ethical challenges. In recent years new paradigms have been developed to circumvent these challenges but none involve using Milgram’s own procedures and asking naïve participants to deliver the maximum level of shock. This was achieved in the present research by using Immersive Digital Realism (IDR) to revisit the OtA paradigm. IDR is a dramatic method that involves a director collaborating with professional actors to develop characters, the strategic withholding of contextual information, and immersion in a real-world environment. 14 actors took part in an IDR study in which they were assigned to conditions that restaged Milgrams’s New Baseline (‘Coronary’) condition and four other variants. Post-experimental interviews also assessed participants’ identification with Experimenter and Learner. Participants’ behaviour closely resembled that observed in Milgram’s original research. In particular, this was evidenced by (a) all being willing to administer shocks greater than 150 volts, (b) near-universal refusal to continue after being told by the Experimenter that “you have no other choice, you must continue” (Milgram’s fourth prod and the one most resembling an order), and (c) a strong correlation between the maximum level of shock that participants administered and the mean maximum shock delivered in the corresponding variant in Milgram’s own research. Consistent with an engaged follower account, relative identification with the Experimenter (vs. the Learner) was also a good predictor of the maximum shock that participants administered. PMID:25730318

Molecular cloning of isoflavone reductase from pea (Pisum sativum L.): evidence for a 3R-isoflavanone intermediate in (+)-pisatin biosynthesis.

PubMed

Paiva, N L; Sun, Y; Dixon, R A; VanEtten, H D; Hrazdina, G

1994-08-01

Isoflavone reductase (IFR) reduces achiral isoflavones to chiral isoflavanones during the biosynthesis of chiral pterocarpan phytoalexins. A cDNA clone for IFR from pea (Pisum sativum) was isolated using the polymerase chain reaction and expressed in Escherichia coli. Analysis of circular dichroism (CD) spectra of the reduction product sophorol obtained using the recombinant enzyme indicated that the isoflavanone possessed the 3R stereochemistry, in contrast to previous reports indicating a 3S-isoflavanone as the product of the pea IFR. Analysis of CD spectra of sophorol produced using enzyme extracts of CuCl2-treated pea seedlings confirmed the 3R stereochemistry. Thus, the stereochemistry of the isoflavanone intermediate in (+)-pisatin biosynthesis in pea is the same as that in (-)-medicarpin biosynthesis in alfalfa, although the final pterocarpans have the opposite stereochemistry. At the amino acid level the pea IFR cDNA was 91.8 and 85.2% identical to the IFRs from alfalfa and chickpea, respectively. IFR appears to be encoded by a single gene in pea. Its transcripts are highly induced in CuCl2-treated seedlings, consistent with the appearance of IFR enzyme activity and pisatin accumulation.

Dynamic rupture scenarios from Sumatra to Iceland - High-resolution earthquake source physics on natural fault systems

NASA Astrophysics Data System (ADS)

Gabriel, A. A.; Madden, E. H.; Ulrich, T.; Wollherr, S.

2016-12-01

Capturing the observed complexity of earthquake sources in dynamic rupture simulations may require: non-linear fault friction, thermal and fluid effects, heterogeneous fault stress and strength initial conditions, fault curvature and roughness, on- and off-fault non-elastic failure. All of these factors have been independently shown to alter dynamic rupture behavior and thus possibly influence the degree of realism attainable via simulated ground motions. In this presentation we will show examples of high-resolution earthquake scenarios, e.g. based on the 2004 Sumatra-Andaman Earthquake and a potential rupture of the Husavik-Flatey fault system in Northern Iceland. The simulations combine a multitude of representations of source complexity at the necessary spatio-temporal resolution enabled by excellent scalability on modern HPC systems. Such simulations allow an analysis of the dominant factors impacting earthquake source physics and ground motions given distinct tectonic settings or distinct focuses of seismic hazard assessment. Across all simulations, we find that fault geometry concurrently with the regional background stress state provide a first order influence on source dynamics and the emanated seismic wave field. The dynamic rupture models are performed with SeisSol, a software package based on an ADER-Discontinuous Galerkin scheme for solving the spontaneous dynamic earthquake rupture problem with high-order accuracy in space and time. Use of unstructured tetrahedral meshes allows for a realistic representation of the non-planar fault geometry, subsurface structure and bathymetry. The results presented highlight the fact that modern numerical methods are essential to further our understanding of earthquake source physics and complement both physic-based ground motion research and empirical approaches in seismic hazard analysis.

Dynamic rupture scenarios from Sumatra to Iceland - High-resolution earthquake source physics on natural fault systems

NASA Astrophysics Data System (ADS)

Gabriel, Alice-Agnes; Madden, Elizabeth H.; Ulrich, Thomas; Wollherr, Stephanie

2017-04-01

Capturing the observed complexity of earthquake sources in dynamic rupture simulations may require: non-linear fault friction, thermal and fluid effects, heterogeneous fault stress and fault strength initial conditions, fault curvature and roughness, on- and off-fault non-elastic failure. All of these factors have been independently shown to alter dynamic rupture behavior and thus possibly influence the degree of realism attainable via simulated ground motions. In this presentation we will show examples of high-resolution earthquake scenarios, e.g. based on the 2004 Sumatra-Andaman Earthquake, the 1994 Northridge earthquake and a potential rupture of the Husavik-Flatey fault system in Northern Iceland. The simulations combine a multitude of representations of source complexity at the necessary spatio-temporal resolution enabled by excellent scalability on modern HPC systems. Such simulations allow an analysis of the dominant factors impacting earthquake source physics and ground motions given distinct tectonic settings or distinct focuses of seismic hazard assessment. Across all simulations, we find that fault geometry concurrently with the regional background stress state provide a first order influence on source dynamics and the emanated seismic wave field. The dynamic rupture models are performed with SeisSol, a software package based on an ADER-Discontinuous Galerkin scheme for solving the spontaneous dynamic earthquake rupture problem with high-order accuracy in space and time. Use of unstructured tetrahedral meshes allows for a realistic representation of the non-planar fault geometry, subsurface structure and bathymetry. The results presented highlight the fact that modern numerical methods are essential to further our understanding of earthquake source physics and complement both physic-based ground motion research and empirical approaches in seismic hazard analysis.

Structure elucidation of nigricanoside A through enantioselective total synthesis† †Electronic supplementary information (ESI) available: Complete experimental details and characterization data. See DOI: 10.1039/c5sc00281h Click here for additional data file.

PubMed Central

Chen, Jie; Koswatta, Panduka; DeBergh, J. Robb; Fu, Peng; Pan, Ende

2015-01-01

Nigricanoside A was isolated from green alga, and its dimethyl ester was found to display potent cytotoxicity. Its scarcity prevented a full structure elucidation, leaving total synthesis as the only means to determine its relative and absolute stereochemistry and to explore its biological activity. Here we assign the stereochemistry of the natural product through enantioselective total synthesis and provide initial studies of its cytotoxicity. PMID:26877863

Surfactant Effects on Structure and Mechanical Properties of Ultrahigh-Molecular-Weight Polyethylene/Layered Silicate Composites.

PubMed

Nikiforov, Leonid A; Okhlopkova, Tatinana A; Kapitonova, Iullia V; Sleptsova, Sardana A; Okhlopkova, Aitalina A; Shim, Ee Le; Cho, Jin-Ho

2017-12-05

In this study, the reinforcement of ultrahigh-molecular-weight polyethylene (UHMWPE) with biotite was investigated. The biotite filler was mechanically activated with different dry surfactants to improve its compatibility with UHMWPE and decrease agglomeration among biotite particles. Alkyldimethylbenzylammonium chloride (ADBAC) and cetyltrimethylammonium bromide (CTAB) were selected as cationic surfactants. The tensile strength of composites containing 1 wt % of CTAB-treated biotite was increased by 30% relative to those with untreated biotite, but was unchanged with ADBAC treatment of the same biotite content. The stereochemistry of the surfactant may be critical to the composite structure and mechanical properties of the material. The stereochemistry of CTAB was preferable to that of ADBAC in enhancing mechanical properties because the stereochemistry of ADBAC impedes favorable interactions with the biotite surface during mechanical activation.

A stereochemical examination of the equine metabolism of 17alpha-methyltestosterone.

PubMed

McKinney, Andrew R; Suann, Craig J; Stenhouse, Allen M

2007-01-09

An investigation was conducted into the stereochemistry of the equine urinary metabolites of 17alpha-methyltestosterone observed after oral administration. Standards of the complete range of C3/C5/C16 stereoisomeric 17alpha-methylandrostane-3,17beta-diols, 17alpha-methylandrostane-3,16,17beta-triols and 17alpha-hydroxymethylandrostane-3,17beta-diols were purchased or synthesised, and were used to unequivocally identify the absolute structures of the metabolites. Phase I metabolism was found to involve combinations of Delta(4)-3-ketone reduction with both 5alpha,3beta- and 5beta,3alpha-stereochemistry, hydroxylation at C16 with both 16alpha- and 16beta-stereochemistry and hydroxylation of the 17alpha-methyl substituent. Phase II metabolism involved mainly sulfation with a lesser degree of beta-glucuronidation.

On the usefulness of the concept of presence in virtual reality applications

NASA Astrophysics Data System (ADS)

Mestre, Daniel R.

2015-03-01

Virtual Reality (VR) leads to realistic experimental situations, while enabling researchers to have deterministic control on these situations, and to precisely measure participants' behavior. However, because more realistic and complex situations can be implemented, important questions arise, concerning the validity and representativeness of the observed behavior, with reference to a real situation. One example is the investigation of a critical (virtually dangerous) situation, in which the participant knows that no actual threat is present in the simulated situation, and might thus exhibit a behavioral response that is far from reality. This poses serious problems, for instance in training situations, in terms of transfer of learning to a real situation. Facing this difficult question, it seems necessary to study the relationships between three factors: immersion (physical realism), presence (psychological realism) and behavior. We propose a conceptual framework, in which presence is a necessary condition for the emergence of a behavior that is representative of what is observed in real conditions. Presence itself depends not only on physical immersive characteristics of the Virtual Reality setup, but also on contextual and psychological factors.

Experimental test of quantum nonlocality in three-photon Greenberger-Horne-Zeilinger entanglement

PubMed

Pan; Bouwmeester; Daniell; Weinfurter; Zeilinger

2000-02-03

Bell's theorem states that certain statistical correlations predicted by quantum physics for measurements on two-particle systems cannot be understood within a realistic picture based on local properties of each individual particle-even if the two particles are separated by large distances. Einstein, Podolsky and Rosen first recognized the fundamental significance of these quantum correlations (termed 'entanglement' by Schrodinger) and the two-particle quantum predictions have found ever-increasing experimental support. A more striking conflict between quantum mechanical and local realistic predictions (for perfect correlations) has been discovered; but experimental verification has been difficult, as it requires entanglement between at least three particles. Here we report experimental confirmation of this conflict, using our recently developed method to observe three-photon entanglement, or 'Greenberger-Horne-Zeilinger' (GHZ) states. The results of three specific experiments, involving measurements of polarization correlations between three photons, lead to predictions for a fourth experiment; quantum physical predictions are mutually contradictory with expectations based on local realism. We find the results of the fourth experiment to be in agreement with the quantum prediction and in striking conflict with local realism.

Bohmian mechanics without wave function ontology

NASA Astrophysics Data System (ADS)

Solé, Albert

2013-11-01

In this paper, I critically assess different interpretations of Bohmian mechanics that are not committed to an ontology based on the wave function being an actual physical object that inhabits configuration space. More specifically, my aim is to explore the connection between the denial of configuration space realism and another interpretive debate that is specific to Bohmian mechanics: the quantum potential versus guidance approaches. Whereas defenders of the quantum potential approach to the theory claim that Bohmian mechanics is better formulated as quasi-Newtonian, via the postulation of forces proportional to acceleration; advocates of the guidance approach defend the notion that the theory is essentially first-order and incorporates some concepts akin to those of Aristotelian physics. Here I analyze whether the desideratum of an interpretation of Bohmian mechanics that is both explanatorily adequate and not committed to configuration space realism favors one of these two approaches to the theory over the other. Contrary to some recent claims in the literature, I argue that the quasi-Newtonian approach based on the idea of a quantum potential does not come out the winner.

Computationally Aided Absolute Stereochemical Determination of Enantioenriched Amines.

PubMed

Zhang, Jun; Gholami, Hadi; Ding, Xinliang; Chun, Minji; Vasileiou, Chrysoula; Nehira, Tatsuo; Borhan, Babak

2017-03-17

A simple and efficient protocol for sensing the absolute stereochemistry and enantiomeric excess of chiral monoamines is reported. Preparation of the sample requires a single-step reaction of the 1,1'-(bromomethylene)dinaphthalene (BDN) with the chiral amine. Analysis of the exciton coupled circular dichroism generated from the BDN-derivatized chiral amine sample, along with comparison to conformational analysis performed computationally, yields the absolute stereochemistry of the parent chiral monoamine.

Utility of Automatic Lighting Design in 3-D Virtual Training Environment

DTIC Science & Technology

2004-01-01

Many training environments have emphasized realism . Although realism may be important for many training applications, it is not essential for...achieving presence, attention, and emotional engagement (Zimmons, 2004). Also, realism is not always in conflict with providing atmosphere or mood, as...applied to the scene to heighten the audience’s emotional experience, while maintaining the perceived realism of the environment portrayed (Block, 2001

Connecting with patients and instilling realism in an era of emerging communication possibilities: a review on palliative care communication heading to telecare practice.

PubMed

van Gurp, Jelle; Hasselaar, Jeroen; van Leeuwen, Evert; Hoek, Patrick; Vissers, Kris; van Selm, Martine

2013-12-01

Appropriate palliative care communication is pivotal to optimizing the quality of life in dying patients and their families. This review aims at describing communication patterns in palliative care and discussing potential relations between communication patterns and upcoming telecare in the practice of palliative care. This review builds on a systematic five-step qualitative analysis of the selected articles: 1. Development of a 'descriptive table of studies reviewed' based on the concept of genre, 2. Open coding of table content and first broad clustering of codes, 3. Intracluster categorization of inductive codes into substantive categories, 4. Constant inter- and intracluster comparison results in identification of genres, and 5. Labeling of genres. This review includes 71 articles. In the analysis, two communication genres in palliative care proved to be dominant: the conversation to connect, about creating and maintaining a professional-patient/family relationship, and the conversation to instill realism, about telling a clinical truth without diminishing hope. The abovementioned two genres clarify a logical intertwinement between communicative purposes, the socio-ethical background underlying palliative care practice and elements of form. Our study supports understanding of current communication in palliative care and anticipates future communicative actions in an era of new communication technologies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The Modernization of the Chinese People’s Liberation Army: Goals and Problems.

DTIC Science & Technology

1980-06-01

been deployed. Nearly 200 MIRE.s and IRBMs had been deployed along the Trans- Siberian Railway, including some of the new SS-20 IRB4s with MIRV...39. U. S., Congress, Mouse , A New Realism, p. 44. 40. Beiing Review, No. 11, 17 March 1980, p. 9. Note: it covers The areas of physics, chemistry

Integrating 3D geological information with a national physically-based hydrological modelling system

NASA Astrophysics Data System (ADS)

Lewis, Elizabeth; Parkin, Geoff; Kessler, Holger; Whiteman, Mark

2016-04-01

Robust numerical models are an essential tool for informing flood and water management and policy around the world. Physically-based hydrological models have traditionally not been used for such applications due to prohibitively large data, time and computational resource requirements. Given recent advances in computing power and data availability, a robust, physically-based hydrological modelling system for Great Britain using the SHETRAN model and national datasets has been created. Such a model has several advantages over less complex systems. Firstly, compared with conceptual models, a national physically-based model is more readily applicable to ungauged catchments, in which hydrological predictions are also required. Secondly, the results of a physically-based system may be more robust under changing conditions such as climate and land cover, as physical processes and relationships are explicitly accounted for. Finally, a fully integrated surface and subsurface model such as SHETRAN offers a wider range of applications compared with simpler schemes, such as assessments of groundwater resources, sediment and nutrient transport and flooding from multiple sources. As such, SHETRAN provides a robust means of simulating numerous terrestrial system processes which will add physical realism when coupled to the JULES land surface model. 306 catchments spanning Great Britain have been modelled using this system. The standard configuration of this system performs satisfactorily (NSE > 0.5) for 72% of catchments and well (NSE > 0.7) for 48%. Many of the remaining 28% of catchments that performed relatively poorly (NSE < 0.5) are located in the chalk in the south east of England. As such, the British Geological Survey 3D geology model for Great Britain (GB3D) has been incorporated, for the first time in any hydrological model, to pave the way for improvements to be made to simulations of catchments with important groundwater regimes. This coupling has involved

Mathematical and physical meaning of the Bell inequalities

NASA Astrophysics Data System (ADS)

Santos, Emilio

2016-09-01

It is shown that the Bell inequalities are closely related to the triangle inequalities involving distance functions amongst pairs of random variables with values \\{0,1\\}. A hidden variables model may be defined as a mapping between a set of quantum projection operators and a set of random variables. The model is noncontextual if there is a joint probability distribution. The Bell inequalities are necessary conditions for its existence. The inequalities are most relevant when measurements are performed at space-like separation, thus showing a conflict between quantum mechanics and local realism (Bell's theorem). The relations of the Bell inequalities with contextuality, the Kochen-Specker theorem, and quantum entanglement are briefly discussed.

ON THE RELATIONSHIPS OF SUBSTRATE ORIENTATION, HYDROGEN ABSTRACTION AND PRODUCT STEREOCHEMISTRY IN SINGLE AND DOUBLE DIOXYGENATIONS BY SOYBEAN LIPOXYGENASE-1 AND ITS ALA542GLY MUTANT*

PubMed Central

Coffa, Gianguido; Imber, Ann N.; Maguire, Brendan C.; Laxmikanthan, Gurunathan; Schneider, Claus; Gaffney, Betty J.; Brash, Alan R.

2005-01-01

Recent findings associate the control of stereochemistry in lipoxygenase (LOX) catalysis with a conserved active site alanine for S configuration hydroperoxide products, or a corresponding glycine for R stereoconfiguration. To further elucidate the mechanistic basis for this stereocontrol we compared the stereoselectivity of the initiating hydrogen abstraction in soybean LOX-1 and an Ala542Gly mutant that converts linoleic acid to both 13S and 9R configuration hydroperoxide products. Using 11R-3H- and 11S-3H-labeled linoleic acid substrates to examine the initial hydrogen abstraction, we found that all the primary hydroperoxide products were formed with an identical and highly stereoselective proS hydrogen abstraction from C-11 of the substrate (97–99% pro-S selective). This strongly suggests that 9R and 13S oxygenations occur with the same binding orientation of substrate in the active site, and as the equivalent 9R and 13S products were formed from a bulky ester derivative (1-palmitoyl-2-linoleoyl-phosphatidylcholine), one can infer that the orientation is tail-first. Both the EPR spectrum and the reaction kinetics were altered by the R product-inducing Ala-Gly mutation, indicating a substantial influence of this Ala-Gly substitution extending to the environment of the active site iron. To examine also the reversed orientation of substrate binding, we studied oxygenation of the 15S-hydroperoxide of arachidonic acid by the Ala542Gly mutant soybean LOX-1. In addition to the usual 5S,15S- and 8S,15S-dihydroperoxides, a new product was formed and identified by HPLC, UV, GC-MS and NMR as 9R , 1 5 S -dihydroperoxy-eicosa-5Z,7E,11Z,13E-tetraenoic acid, the R configuration “partner” of the normal 5S,15S product. This provides evidence that both tail-first and carboxylate end-first binding of substrate can be associated with S or R partnerships in product formation in the same active site. PMID:16157595

Predicting Future Capabilities of the People’s Liberation Army Air Forces of China

DTIC Science & Technology

2010-04-01

are important—offensive realism and defensive realism. The author will first discuss the origins of realism in international relations theory ... neoclassical realism. First, the international system is one of anarchy. There is no structural model to regulate international behavior among independent...of Relative Gains in International Politics,” The Journal of Conflict Resolution 46, no. 3 (Jun., 2002): 394. 6 Kenneth N. Waltz, Theory of

Understanding the Professional Socialization of Canadian Physical Therapy Students: A Qualitative Investigation

PubMed Central

Deborah Lucy, S.; Bisbee, Leslie; Conti-Becker, Angela

2009-01-01

ABSTRACT Purpose: To understand the professional socialization of physical therapy (PT) students. Method: Forty-two students enrolled in our newly developed master's degree programme wrote three-page reflective journals on a critical learning incident after each of three selected clinical experiences. The journals were coded and analyzed, and major themes were identified and described. A separate cohort of 44 students participated in focus groups after the same three clinical experiences to check the trustworthiness of the results. Results: Following the first placement, the main themes coded were emotions, self-confidence, professionalism in the real world, communication, and learning by doing. After the intermediate placement, major themes were idealism versus realism, depth of communication with clients, and breadth of communication with family members and colleagues. Aspects of clinical learning were variable, and self-confidence remained an issue. After the final placement, most students were deeply engaged with their clients and self-confidence had developed to the point of self-efficacy. Tensions increased between the concept of ideal practice and the pragmatics of actual practice, and the concept of self as protégé (rather than as object of the supervisor's evaluation) emerged. The themes were subsequently assembled in a booklet with representative quotations. Conclusion: These results contribute to foundational knowledge required by PT educators, including clinical instructors, by explicitly describing the professional socialization of PT students. PMID:20145748

Is This Real Life? Is This Just Fantasy?: Realism and Representations in Learning with Technology

NASA Astrophysics Data System (ADS)

Sauter, Megan Patrice

Students often engage in hands-on activities during science learning; however, financial and practical constraints often limit the availability of these activities. Recent advances in technology have led to increases in the use of simulations and remote labs, which attempt to recreate hands-on science learning via computer. Remote labs and simulations are interesting from a cognitive perspective because they allow for different relations between representations and their referents. Remote labs are unique in that they provide a yoked representation, meaning that the representation of the lab on the computer screen is actually linked to that which it represents: a real scientific device. Simulations merely represent the lab and are not connected to any real scientific devices. However, the type of visual representations used in the lab may modify the effects of the lab technology. The purpose of this dissertation is to examine the relation between representation and technology and its effects of students' psychological experiences using online science labs. Undergraduates participated in two studies that investigated the relation between technology and representation. In the first study, participants performed either a remote lab or a simulation incorporating one of two visual representations, either a static image or a video of the equipment. Although participants in both lab conditions learned, participants in the remote lab condition had more authentic experiences. However, effects were moderated by the realism of the visual representation. Participants who saw a video were more invested and felt the experience was more authentic. In a second study, participants performed a remote lab and either saw the same video as in the first study, an animation, or the video and an animation. Most participants had an authentic experience because both representations evoked strong feelings of presence. However, participants who saw the video were more likely to believe the

The stereochemistry of chlorophyll-c₃ from the haptophyte Emiliania huxleyi: the (13²R)-enantiomers of chlorophylls-c are exclusively selected as the photosynthetically active pigments in chromophyte algae.

PubMed

Mizoguchi, Tadashi; Kimura, Yuki; Yoshitomi, Taichi; Tamiaki, Hitoshi

2011-11-01

Chlorophyll(Chl)-c pigments in algae, diatoms and some prokaryotes are characterized by the fully conjugated porphyrin π-system as well as the acrylate residue at the 17-position. The precise structural characterization of Chl-c(3) from the haptophyte Emiliania huxleyi was performed. The conformations of the π-conjugated peripheral substituents, the 3-/8-vinyl, 7-methoxycarbonyl and 17-acrylate moieties were evaluated, in a solution, using nuclear Overhauser enhancement correlations and molecular modeling calculations. The rotation of the 17-acrylate residue was considerably restricted, whereas the other three substituents readily rotated at ambient temperature. Moreover, the stereochemistry at the 13²-position was determined by combination of chiral high-performance liquid chromatography (HPLC) with circular dichroism (CD) spectroscopy. Compared with the CD spectra of the structurally related, synthetic (13²R)- and (13²S)-protochlorophyllide(PChlide)-a, naturally occurring Chl-c₃ had exclusively the (13²R)-configuration. To elucidate this natural selection of a single enantiomer, we analyzed the three major Chl-c pigments (Chl-c₁, c₂ and c₃) in four phylogenetically distinct classes of Chl-c containing algae, i.e., heterokontophyta, dinophyta, cryptophyta and haptophyta using chiral HPLC. All the photosynthetic organisms contained only the (13²R)-enantiomerically pure Chls-c, and lacked the corresponding enantiomeric (13²S)-forms. Additionally, Chl-c₂ was found in all the organisms as the common Chl-c. These results throw a light on the biosynthesis as well as photosynthetic function of Chl-c pigments: Chl-c₂ is derived from 8-vinyl-PChlide-a by dehydrogenation of the 17-propionate to acrylate residues as generally proposed, and the (13²R)-enantiomers of Chls-c function as photosynthetically active, light-harvesting pigments together with the principal Chl-a and carotenoids. 2011 Elsevier B.V. All rights reserved.

Einstein's ``Spooky Action at a Distance'' in the Light of Kant's Transcendental Doctrine of Space and Time

NASA Astrophysics Data System (ADS)

Hacyan, Shahen

2006-11-01

Since the famous Einstein-Podolsky-Rosen (EPR) paper, it is clear that there is a serious incompatibility between local realism and quantum mechanics. Einstein believed that a complete quantum theory should be free of what he once called "spooky actions at distance". However, all experiments in quantum optics and atomic physics performed in the last two decades confirm the existence of quantum correlations that seem to contradict local realism. According to Bohr, the apparent contradictions disclose only the inadequacy of our customary concepts for the description of the quantum world. Are space and time such customary concepts? In this presentation, I argue that the Copenhagen interpretation is compatible with Kant's transcendental idealism and that, in particular, EPR type paradoxes are consistent with Kant's transcendental aesthetics, according to which space and time have no objective reality but are pure forms of sensible intuition.

Synthesis of new β-amidodehydroaminobutyric acid derivatives and of new tyrosine derivatives using copper catalyzed C-N and C-O coupling reactions.

PubMed

Pereira, G; Vilaça, H; Ferreira, P M T

2013-02-01

Several β-amidodehydroaminobutyric acid derivatives were prepared from N,C-diprotected β-bromodehydroaminobutyric acids and amides by a copper catalyzed C-N coupling reaction. The best reaction conditions include the use of a catalytic amount of CuI, N,N'-dimethylethylenediamine as ligand and K(2)CO(3) as base in toluene at 110 °C. The stereochemistry of the products was determined using NOE difference experiments and the results obtained are in agreement with an E-stereochemistry. Thus, the stereochemistry is maintained in the case of the E-isomers of β-bromodehydroaminobutyric acid derivatives, but when the Z-isomers were used as substrates the reaction proceeds with inversion of configuration. The use of β-bromodehydrodipeptides as substrates was also tested. It was found that the reaction outcome depend on the stereochemistry of the β-bromodehydrodipeptide and on the nature of the first amino acid residue. The products isolated were the β-amidodehydrodipeptide derivatives and/or the corresponding dihydropyrazines. The same catalytic system (CuI/N,N'-dimethylethylene diamine) was used in the C-O coupling reactions between a tyrosine derivative and aryl bromides. The new O-aryltyrosine derivatives were isolated in moderate to good yields. The photophysical properties of two of these compounds were studied in four solvents of different polarity. The results show that these compounds after deprotection can be used as fluorescence markers.

Forensic 3D Visualization of CT Data Using Cinematic Volume Rendering: A Preliminary Study.

PubMed

Ebert, Lars C; Schweitzer, Wolf; Gascho, Dominic; Ruder, Thomas D; Flach, Patricia M; Thali, Michael J; Ampanozi, Garyfalia

2017-02-01

The 3D volume-rendering technique (VRT) is commonly used in forensic radiology. Its main function is to explain medical findings to state attorneys, judges, or police representatives. New visualization algorithms permit the generation of almost photorealistic volume renderings of CT datasets. The objective of this study is to present and compare a variety of radiologic findings to illustrate the differences between and the advantages and limitations of the current VRT and the physically based cinematic rendering technique (CRT). Seventy volunteers were shown VRT and CRT reconstructions of 10 different cases. They were asked to mark the findings on the images and rate them in terms of realism and understandability. A total of 48 of the 70 questionnaires were returned and included in the analysis. On the basis of most of the findings presented, CRT appears to be equal or superior to VRT with respect to the realism and understandability of the visualized findings. Overall, in terms of realism, the difference between the techniques was statistically significant (p < 0.05). Most participants perceived the CRT findings to be more understandable than the VRT findings, but that difference was not statistically significant (p > 0.05). CRT, which is similar to conventional VRT, is not primarily intended for diagnostic radiologic image analysis, and therefore it should be used primarily as a tool to deliver visual information in the form of radiologic image reports. Using CRT for forensic visualization might have advantages over using VRT if conveying a high degree of visual realism is of importance. Most of the shortcomings of CRT have to do with the software being an early prototype.

(Dis)entangling Barad: Materialisms and ethics.

PubMed

Hollin, Gregory; Forsyth, Isla; Giraud, Eva; Potts, Tracey

2017-12-01

In the wake of the widespread uptake of and debate surrounding the work of Karen Barad, this article revisits her core conceptual contributions. We offer descriptions, elaborations, problematizations and provocations for those intrigued by or invested in this body of work. We examine Barad's use of quantum physics, which underpins her conception of the material world. We discuss the political strengths of this position but also note tensions associated with applying quantum physics to phenomena at macro-scales. We identify both frictions and unacknowledged affinities with science and technology studies in Barad's critique of reflexivity and her concept of diffraction. We flesh out Barad's overarching position of 'agential realism', which contains a revised understanding of scientific apparatuses. Building upon these discussions, we argue that inherent in agential realism is both an ethics of inclusion and an ethics of exclusion. Existing research has, however, frequently emphasized entanglement and inclusion to the detriment of foreclosure and exclusion. Nonetheless, we contend that it is in the potential for an ethics of exclusion that Barad's work could be of greatest utility within science and technology studies and beyond.

A new rearranged dolabellane diterpene from the soft coral Clavularia inflata.

PubMed

Alea, Glenn V; Bowden, Bruce F; Ragasa, Consolacion Y

2008-06-15

A new dolabellane type diterpene 1 has been isolated through its acetate 1a. The structure of 1a was elucidated by extensive 1D and 2D NMR spectroscopy and confirmed by mass spectrometry. The structure of 1 was deduced by comparison of its NMR spectral data with those of 1a, while its relative stereochemistry was deduced by NOESY. The absolute stereochemistry of C-7 was determined by analyses of 1 separately esterified with R and S O-mandelic acids.

Role of Chirality in Drugs… An Overview

PubMed

Alkadi, Hourieh; Jbeily, Rajwa

2017-03-29

Stereochemistry has been occupied a great role in manufacture and development of pharmaceuti-cals. Chiral properties play an important role in the determination of pharmacological actions of the drug. In recent years, there is a considerable interest in chiral separation to isolate and examine both enantiomers. This article provides an overview about the stereochemistry and its role in drugs, and also, offers approved isolation methods for enantiomeric pairs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Grasping the Concepts of Stereochemistry.

ERIC Educational Resources Information Center

Barta, Nancy S.; Stille, John R.

1994-01-01

Presents an effective means of determining the R or S configuration of chiral molecules using the Cahn Ingold Prelog (CIP) sequence rules to establish substituent priority and use of the ultimate model of chirality, the hands, to aid in the direct correlation and assignment of relative configuration. (ZWH)

Polyhedron Modeling of Rubble-Pile Asteroids

NASA Technical Reports Server (NTRS)

Korycansky, D. G.; Asphaug, E.

2005-01-01

We report on progress in modeling of asteroids as collections of rigid polyhedra ("rubble piles"). Such models are (idealized) candidates for asteroid structures: aggregates of irregular rocky subunits that are held together by self-gravity and friction. We have taken several steps toward greater realism and physical interest in construction of the models (although the gravitational fields are being treated in a simplified manner). -

Quinolizidine alkaloids from Lupinus lanatus

NASA Astrophysics Data System (ADS)

Neto, Alexandre T.; Oliveira, Carolina Q.; Ilha, Vinicius; Pedroso, Marcelo; Burrow, Robert A.; Dalcol, Ionara I.; Morel, Ademir F.

2011-10-01

In this study, one new quinolizidine alkaloid, lanatine A ( 1), together with three other known alkaloids, 13-α- trans-cinnamoyloxylupanine ( 2), 13-α-hydroxylupanine ( 3), and (-)-multiflorine ( 4) were isolated from the aerial parts of Lupinus lanatus (Fabaceae). The structures of alkaloids 1- 4 were elucidated by spectroscopic data analysis. The stereochemistry of 1 was determined by single crystal X-ray analysis. Bayesian statistical analysis of the Bijvoet differences suggests the absolute stereochemistry of 1. In addition, the antimicrobial potential of alkaloids 1- 4 is also reported.

Book Review: Book review

NASA Astrophysics Data System (ADS)

Wüthrich, Christian

Symmetry considerations stand at the core of classical and quantum physics. No modern-and few older-physical theories forgo the immense services that these considerations offer. It is therefore only natural that philosophers of physics have increasingly started to study the motivations for, as well as the technical implementations and the interpretative implications of, symmetries in fundamental physics. Apart from the extraordinary foundational interest of symmetries, they provide a vehicle to study more general philosophical issues such as the relation between the physical world and its representations and between physics and mathematics. Moreover, traditional problems in metaphysics and philosophy of science such as the nature and status of laws of nature, scientific realism, and determinism naturally arise in, and enjoy substantial fertilisation from, the context of symmetries in physics.

Marxist Influences and South Asian Literature. South Asia Series Occasional Paper No. 23, Vol. II.

ERIC Educational Resources Information Center

Coppola, Carlo, Ed.

This document is the second of two volumes of papers dealing with various aspects of Marxist literary influence, and more specifically socialist realism, in India, Pakistan, and Bangladesh. Included in this volume are articles that deal with such subjects as socialist realism and the progressive movement in Malayalam, realism in Marathi creative…

Anti-Helicobacter pylori activity of derivatives of the phthalide-containing antibacterial agents spirolaxine methyl ether, CJ-12,954, CJ-13,013, CJ-13,102, CJ-13,104, CJ-13,108 and CJ-13,015.

PubMed

Radcliff, Fiona J; Fraser, John D; Wilson, Zoe E; Heapy, Amanda M; Robinson, James E; Bryant, Christina J; Flowers, Christopher L; Brimble, Margaret A

2008-06-01

The naturally occurring phthalide-containing antibiotics spirolaxine methyl ether, CJ-12,954, CJ-13,013, CJ-13,015, CJ-13,102, CJ-13,103, CJ-13,104 and CJ-13,108, have been reported to exhibit anti-H. pylori activity. However, the exact stereochemistry of spirolaxine methyl ether, CJ-12,954 or CJ-13,013, contributing to this observed activity has not been confirmed. The anti-H. pylori activity of several analogues of spirolaxine methyl ether, CJ-12,954 and CJ-13,013 of defined stereochemistry together with the anti-H. pylori activity of several indole analogues of the simpler phthalide-containing antibiotics CJ-13,102, CJ-13,104, CJ-13,108 and CJ-13,015 is reported herein. A 1:1 mixture of spiroacetals 5b and 6b in which the phthalide substituent exhibited (3R)-stereochemistry was sixty times more active than the corresponding 1:1 mixture of spiroacetals with (3S)-stereochemistry. Notably, the unnatural (2''S)-diastereomer of spirolaxine methyl ether exhibited more potent anti-H. pylori activity than the natural product spirolaxine methyl ether. The 4,6-dimethoxyindoles 9, 10, 11 and 13 were all found to be less active than their parent compounds 1, 2, 3 and 4, respectively. Chain-shortened 4,6-dimethoxyindole analogue 12 of CJ-13,108 3 and 4,6-dimethoxyindole-spiroacetal 13 exhibited weak anti-H. pylori activity thus providing future opportunity for drug discovery programs.

ADDING REALISM TO NUCLEAR MATERIAL DISSOLVING ANALYSIS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williamson, B.

2011-08-15

Two new criticality modeling approaches have greatly increased the efficiency of dissolver operations in H-Canyon. The first new approach takes credit for the linear, physical distribution of the mass throughout the entire length of the fuel assembly. This distribution of mass is referred to as the linear density. Crediting the linear density of the fuel bundles results in using lower fissile concentrations, which allows higher masses to be charged to the dissolver. Also, this approach takes credit for the fact that only part of the fissile mass is wetted at a time. There are multiple assemblies stacked on top ofmore » each other in a bundle. On average, only 50-75% of the mass (the bottom two or three assemblies) is wetted at a time. This means that only 50-75% (depending on operating level) of the mass is moderated and is contributing to the reactivity of the system. The second new approach takes credit for the progression of the dissolving process. Previously, dissolving analysis looked at a snapshot in time where the same fissile material existed both in the wells and in the bulk solution at the same time. The second new approach models multiple consecutive phases that simulate the fissile material moving from a high concentration in the wells to a low concentration in the bulk solution. This approach is more realistic and allows higher fissile masses to be charged to the dissolver.« less

Fresnel's laws, ceteris paribus.

PubMed

Wright, Aaron Sidney

2017-08-01

This article is about structural realism, historical continuity, laws of nature, and ceteris paribus clauses. Fresnel's Laws of optics support Structural Realism because they are a scientific structure that has survived theory change. However, the history of Fresnel's Laws which has been depicted in debates over realism since the 1980s is badly distorted. Specifically, claims that J. C. Maxwell or his followers believed in an ontologically-subsistent electromagnetic field, and gave up the aether, before Einstein's annus mirabilis in 1905 are indefensible. Related claims that Maxwell himself did not believe in a luminiferous aether are also indefensible. This paper corrects the record. In order to trace Fresnel's Laws across significant ontological changes, they must be followed past Einstein into modern physics and nonlinear optics. I develop the philosophical implications of a more accurate history, and analyze Fresnel's Laws' historical trajectory in terms of dynamic ceteris paribus clauses. Structuralists have not embraced ceteris paribus laws, but they continue to point to Fresnel's Laws to resist anti-realist arguments from theory change. Fresnel's Laws fit the standard definition of a ceteris paribus law as a law applicable only in particular circumstances. Realists who appeal to the historical continuity of Fresnel's Laws to combat anti-realists must incorporate ceteris paribus laws into their metaphysics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Differentiation with Stratification: A Principle of Theoretical Physics in the Tradition of the Memory Art

NASA Astrophysics Data System (ADS)

Pombo, Claudia

2015-10-01

The art of memory started with Aristotle's questions on memory. During its long evolution, it had important contributions from alchemists, was transformed by Ramon Llull and apparently ended with Giordano Bruno, who was considered the best known representative of this art. This tradition did not disappear, but lives in the formulations of our modern scientific theories. From its initial form as a method of keeping information via associations, it became a principle of classification and structuring of knowledge. This principle, which we here name differentiation with stratification, is a structural design behind classical mechanics. Integrating two different traditions of science in one structure, this physical theory became the modern paradigm of science. In this paper, we show that this principle can also be formulated as a set of questions. This is done via an analysis of theories, based on the epistemology of observational realism. A combination of Rudolph Carnap's concept of theory as a system of observational and theoretical languages, with a criterion for separating observational languages, based on analytical psychology, shapes this epistemology. The `nuclear' role of the observational laws and the differentiations from these nucleus, reproducing the general cases of phenomena, reveals the memory art's heritage in the theories. Here in this paper we argue that this design is also present in special relativity and in quantum mechanics.

Improving Realism in Reduced Gravity Simulators

NASA Technical Reports Server (NTRS)

Cowley, Matthew; Harvil, Lauren; Clowers, Kurt; Clark, Timothy; Rajulu, Sudhakar

2010-01-01

Since man was first determined to walk on the moon, simulating the lunar environment became a priority. Providing an accurate reduced gravity environment is crucial for astronaut training and hardware testing. This presentation will follow the development of reduced gravity simulators to a final comparison of environments between the currently used systems. During the Apollo program era, multiple systems were built and tested, with several NASA centers having their own unique device. These systems ranged from marionette-like suspension devices where the subject laid on his side, to pneumatically driven offloading harnesses, to parabolic flights. However, only token comparisons, if any, were made between systems. Parabolic flight allows the entire body to fall at the same rate, giving an excellent simulation of reduced gravity as far as the biomechanics and physical perceptions are concerned. While the effects are accurate, there is limited workspace, limited time, and high cost associated with these tests. With all mechanical offload systems only the parts of the body that are actively offloaded feel any reduced gravity effects. The rest of the body still feels the full effect of gravity. The Partial Gravity System (Pogo) is the current ground-based offload system used to training and testing at the NASA Johnson Space Center. The Pogo is a pneumatic type system that allows for offloaded motion in the z-axis and free movement in the x-axis, but has limited motion in the y-axis. The pneumatic system itself is limited by cylinder stroke length and response time. The Active Response Gravity Offload System (ARGOS) is a next generation groundbased offload system, currently in development, that is based on modern robotic manufacturing lines. This system is projected to provide more z-axis travel and full freedom in both the x and y-axes. Current characterization tests are underway to determine how the ground-based offloading systems perform, how they compare to parabolic

Synthesis, characterization and electrochemical studies of some Ni(II)Cu(II) heterobimetallic complexes derived from succinoyldihydrazones.

PubMed

Borthakur, R; Kumar, A; Lal, R A

2015-10-05

Synthesis, structural characterization and redox properties of three heterobimetallic complexes with formule {[NiCu(L(n))(CH3OH)3]·CH3OH} using [Cu(H2L(n))(H2O)] as metalloligand have been demonstrated in the present paper. Electronic spectroscopy suggests that the copper center has a pseudo square pyramidal stereochemistry in all the complexes while the nickel center has a distorted octahedral stereochemistry. The electron transfer reactions of the complexes have been investigated by cyclic voltammetry. Copyright © 2015 Elsevier B.V. All rights reserved.

Small-Molecule Inhibitor Leads of Ribosome-Inactivating Proteins Developed Using the Doorstop Approach

DTIC Science & Technology

2011-03-01

stereochemistry of R22 used in our virtual screen. R20 or R20b was prepared by coupling 4-formylbenzoic acid with a substituted pyrrole in the keto form for R20 or...a mixture of keto and enol forms for R20b according to a reported process [42] (Figure 4). The substituted pyrrole was obtained via cyclization of 2...1H- pyrrole -3-carboxylate—a close ana- log of R20b—has been reported to have the Z stereochemistry [45]. Therefore, identification of R20 as an active

Crown ether stereoisomerism: Implications in metal ion extraction and ionic liquid design

NASA Astrophysics Data System (ADS)

Pawlak, Alan J.

Since their discovery more than four decades ago, crown ethers (CEs) have been the subject of intense investigation in a number of fields. Although many of the structural features that govern the behavior of these compounds have been thoroughly explored, the effect of their stereochemistry has received relatively little attention. In the present work, crown ether stereochemistry is shown to have important implications in both the design of ternary (i.e., three-component) ionic liquids (TILs) and metal ion extraction. Specifically, as a first step toward the development of guidelines for the rational design of ternary ionic liquids employing crown ethers as the neutral extractant, a systematic examination of the effect of crown ether stereochemistry (employing dicyclohexano-18-crown-6 (DCH18C6) as a representative crown compound), along with ring size, the nature and number of donor atoms, and the presence of functional groups, on the thermal properties (i.e., melting point or glass transition; decomposition or evaporation) of these compounds was carried out. Stereochemistry was found to have no appreciable impact on the onset temperature for mass loss. Rather, molecular weight and aromaticity were found to be more influential. Stereochemistry was, however, found to significantly affect the melting point of a TIL prepared from it; while the metal-CE formation constant, which varies with stereoisomer was observed to determine the onset temperature for mass loss of the TIL. To explore the implications of crown ether stereoisomerism in metal ion extraction, the formation constants for alkaline earth cation complexes with the isomers of DCH18C6 and selected stereoisomers of di-tert-butylcyclohexano-18-crown-6 (DtBuCH18C6) were measured. These values were found to vary inversely with the ligand strain (i.e., reorganizational) energy for the isomer, as determined by molecular mechanics calculations. Using this relationship (along with additional identification methods

Utilization of virtual reality for endotracheal intubation training.

PubMed

Mayrose, James; Kesavadas, T; Chugh, Kevin; Joshi, Dhananjay; Ellis, David G

2003-10-01

Tracheal intubation is performed for urgent airway control in injured patients. Current methods of training include working on cadavers and manikins, which lack the realism of a living human being. Work in this field has been limited due to the complex nature of simulating in real-time, the interactive forces and deformations which occur during an actual patient intubation. This study addressed the issue of intubation training in an attempt to bridge the gap between actual and virtual patient scenarios. The haptic device along with the real-time performance of the simulator give it both visual and physical realism. The three-dimensional viewing and interaction available through virtual reality make it possible for physicians, pre-hospital personnel and students to practice many endotracheal intubations without ever touching a patient. The ability for a medical professional to practice a procedure multiple times prior to performing it on a patient will both enhance the skill of the individual while reducing the risk to the patient.

Shifty: A Weight-Shifting Dynamic Passive Haptic Proxy to Enhance Object Perception in Virtual Reality.

PubMed

Zenner, Andre; Kruger, Antonio

2017-04-01

We define the concept of Dynamic Passive Haptic Feedback (DPHF) for virtual reality by introducing the weight-shifting physical DPHF proxy object Shifty. This concept combines actuators known from active haptics and physical proxies known from passive haptics to construct proxies that automatically adapt their passive haptic feedback. We describe the concept behind our ungrounded weight-shifting DPHF proxy Shifty and the implementation of our prototype. We then investigate how Shifty can, by automatically changing its internal weight distribution, enhance the user's perception of virtual objects interacted with in two experiments. In a first experiment, we show that Shifty can enhance the perception of virtual objects changing in shape, especially in length and thickness. Here, Shifty was shown to increase the user's fun and perceived realism significantly, compared to an equivalent passive haptic proxy. In a second experiment, Shifty is used to pick up virtual objects of different virtual weights. The results show that Shifty enhances the perception of weight and thus the perceived realism by adapting its kinesthetic feedback to the picked-up virtual object. In the same experiment, we additionally show that specific combinations of haptic, visual and auditory feedback during the pick-up interaction help to compensate for visual-haptic mismatch perceived during the shifting process.

The Morality of Employing Remotely Piloted Weapon Systems in Combat

DTIC Science & Technology

2013-03-01

ethics of remotely piloted weapon systems involve utilitarianism and Just War Theory. Although the other two perspectives, pacifism and realism, do...perspectives of utilitarianism , Just War Theory, pacifism, and realism are evaluated to justify the claim. With the exception of pacifism, each of these...of utilitarianism , Just War Theory, pacifism, and realism are evaluated to justify the claim. With the exception of pacifism, each of these

The Troubled Relationship Between Israel and the European Union: An Empirical Explanation

DTIC Science & Technology

2015-03-01

the state, and the architecture of the international system.17 Classical realism and structural realism qualify the effects of human nature and the...outcomes in IR is highly constrained by the architecture of the international system. The result is unavoidable competition and power politics...42 Constructivism, like realism, focuses on the architecture of the international system and defines the international system as anarchical in

European Scientific Notes. Volume 37, Number 1.

DTIC Science & Technology

1983-01-31

instantoneous sea-state condition can be tions vary widely in their realism , with computed from a special data base coded some producing dynamic color pictures...between the variables of accuracy, approach channels, the alignment of practicality, realism , and expense. jetties, and the establishment of Because the...tidal current variables The system certainly seems to be valid, have been played into some of the and the smooth dynamics, realism , and simulator runs

USACDEC Experimentation Manual

DTIC Science & Technology

1981-10-01

Commander, Instrumentation Command (Prov) who is responsible for the cinematic form of the films. The writing requirements for discrete sections of the...level of simulated realism required. Higher levels of simulated realism will require higher degrees of control to insure the test events occur as...experimentation, the "enemy" created to add realism . Aggressor forces may be represented by live troops In the field or by mechanical targets with or

Translations of Eastern Europe, Political, Sociological, and Military Affairs. Number 1398.

DTIC Science & Technology

1977-06-09

concentrated realism . Finally, "Tanase Scatiu," a film based on fragments of Duiliu Zamfirescu’s works and put together in a screenplay by MLhnea Gheorgiu...trans- position but rather recreated an actual and psychological universe, the world of the original novels of a century ago, with penetrating realism ...acquire, as well as the atmosphere of an era. A judicious equilibrium is established between the crude realism of the framework and the figurative

Synthesis of the ABC tricyclic fragment of the pectenotoxins via stereocontrolled cyclization of a gamma-hydroxyepoxide appended to the AB spiroacetal unit.

PubMed

Halim, Rosliana; Brimble, Margaret A; Merten, Jörn

2006-04-07

The stereocontrolled synthesis of the C1-C16 ABC spiroacetal-containing tricyclic fragment of pectenotoxin-7 6 has been accomplished. The key AB spiroacetal aldehyde 9 was successfully synthesized via acid catalyzed cyclization of protected ketone precursor 28 that was readily prepared from aldehyde 12 and sulfone 13. The syn stereochemistry in aldehyde 12 was installed using an asymmetric aldol reaction proceeding via a titanium enolate. The stereogenic centre in sulfone 13 was derived from (R)-(+)-glycidol. The absolute stereochemistry of the final spiroacetal aldehyde 9 was confirmed by NOE studies establishing the (S)-stereochemistry of the spiroacetal centre. Construction of the tetrahydrofuran C ring system began with Wittig olefination of the AB spiroacetal aldehyde 9 with (carbethoxyethylidene)triphenylphosphorane 10 affording the desired (E)-olefin 32. Appendage of a three carbon chain to the AB spiroacetal fragment was achieved via addition of acetylene 11 to the unstable allylic iodide 39. Epoxidation of (E)-enyne 8 via in situ formation of L-fructose derived dioxirane generated the desired syn-epoxide 36. Semi-hydrogenation of the resulting epoxide 36 followed by dihydroxylation of the alkene effected concomitant cyclization, thus completing the synthesis of the ABC spiroacetal ring fragment 6.

Stereoselective synthesis of an active metabolite of the potent PI3 kinase inhibitor PKI-179.

PubMed

Chen, Zecheng; Venkatesan, Aranapakam M; Dos Santos, Osvaldo; Delos Santos, Efren; Dehnhardt, Christoph M; Ayral-Kaloustian, Semiramis; Ashcroft, Joseph; McDonald, Leonard A; Mansour, Tarek S

2010-03-05

The synthesis and stereochemical determination of 1-(4-(4-((1R,5R,6R)-6-hydroxy-3-oxa-8-azabicyclo[3.2.1]octan-8-yl)-6-morpholino-1,3,5-triazin-2-yl)phenyl)-3-(pyridin-4-yl)urea (2), an active metabolite of the potent PI3 kinase inhibitor PKI-179 (1), is described. Stereospecific hydroboration of the double bond of 2,5-dihydro-1H-pyrrole 8 gave the 2,3-trans alcohol 9 exclusively. The configuration of the 3-hydroxyl group in 9 was inverted by an oxidation and stereoselective reduction sequence to give the corresponding 2,3-cis isomer 23. Both exo (21) and endo (27) isomers of the metabolite 2 were prepared via a practical synthetic route from 9 and 23, respectively, and the stereochemistry of 2 was determined to be endo. The endo isomer (27) was separated into two enantiomers 28 and 29 by chiral HPLC. Compound 2 was found to be enantiomerically pure and identical to the enantiomer 28. The absolute stereochemistry of the enantiomer 28 was determined by Mosher's method, thus establishing the stereochemistry of the active metabolite 2.

Generating realistic environments for cyber operations development, testing, and training

NASA Astrophysics Data System (ADS)

Berk, Vincent H.; Gregorio-de Souza, Ian; Murphy, John P.

2012-06-01

Training eective cyber operatives requires realistic network environments that incorporate the structural and social complexities representative of the real world. Network trac generators facilitate repeatable experiments for the development, training and testing of cyber operations. However, current network trac generators, ranging from simple load testers to complex frameworks, fail to capture the realism inherent in actual environments. In order to improve the realism of network trac generated by these systems, it is necessary to quantitatively measure the level of realism in generated trac with respect to the environment being mimicked. We categorize realism measures into statistical, content, and behavioral measurements, and propose various metrics that can be applied at each level to indicate how eectively the generated trac mimics the real world.

Synthesis, Properties and Stereochemistry of 2-Halo-1,2λ⁵-oxaphosphetanes.

PubMed

Kolodiazhna, Anastasy O; Kolodiazhnyi, Oleg I

2016-10-17

Results of research into four-membered 2-halo-1,2λ⁵-oxaphosphetane phosphorus(V)-heterocycles are presented. The preparation of 2-halo-1,2λ⁵-oxaphosphetanes by reaction of P- haloylides with carbonyl compounds is described. The mechanism of asynchronous [2+2]-сycloaddition of ylides to aldehydes was proposed on the base of low-temperature NMR investigations. 2-Halo-1,2λ⁵-oxaphosphetanes were isolated as individual compounds and their structures were confirmed by ¹Н-, 13 C-, 19 F- and 31 Р-NMR spectra. These compounds are convenient reagents for preparing of various organic and organophosphorus compounds hardly available by other methods. Chemical and physical properties of the 2-halo-1,2λ⁵-oxaphosphetanes are reviewed. The 2-chloro-1,2λ⁵-oxaphosphetanes, rearrange with formation of 2-chloroalkyl-phosphonates or convert into trans -phosphorylated alkenes depending on the substituents at the α-carbon atom. Prospective synthetic applications of 2-halo-1,2λ⁵-oxaphosphetanes are analyzed. The 2-halo-1,2λ⁵-oxaphosphetanes may be easily converted to various alkenylphosphonates: allyl- or vinylphosphonates, phosphorus ketenes, thioketenes, ketenimines.

A new twist to the No Miracles Argument for the success of science.

PubMed

Wray, K Brad

2018-06-01

J. D. Trout has recently developed a new defense of scientific realism, a new version of the No Miracles Argument. I critically evaluate Trout's novel defense of realism. I argue that Trout's argument for scientific realism and the related explanation for the success of science are self-defeating. In the process of arguing against the traditional realist strategies for explaining the success of science, he inadvertently undermines his own argument. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inversion of Configuration at the Phosphorus Nucleophile in the Diastereoselective and Enantioselective Synthesis of P-Stereogenic syn-Phosphiranes from Chiral Epoxides.

PubMed

Muldoon, Jake A; Varga, Balázs R; Deegan, Meaghan M; Chapp, Timothy W; Eördögh, Ádám M; Hughes, Russell P; Glueck, David S; Moore, Curtis E; Rheingold, Arnold L

2018-04-23

Nucleophilic substitution results in inversion of configuration at the electrophilic carbon center (S N 2) or racemization (S N 1). The stereochemistry of the nucleophile is rarely considered, but phosphines, which have a high barrier to pyramidal inversion, attack electrophiles with retention of configuration at P. Surprisingly, cyclization of bifunctional secondary phosphine alkyl tosylates proceeded under mild conditions with inversion of configuration at the nucleophile to yield P-stereogenic syn-phosphiranes. DFT studies suggested that the novel stereochemistry results from acid-promoted tosylate dissociation to yield an intermediate phosphenium-bridged cation, which undergoes syn-selective cyclization. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Inadequacy of the paradigms of special education to subjects with severe and profound grade intellectual disability - the need for pragmatic realism in psychiatry and special pedagogy].

PubMed

Sipowicz, Kasper; Żuraw, Hanna; Witusik, Andrzej; Mokros, Łukasz; Najbert, Edyta; Pietras, Tadeusz

2018-05-25

People with severe and profound grade disabilities are the subject of interest in psychiatry, clinical psychology and special pedagogy. Unfortunately, the paradigmatic approach to special education based on postmodern philosophy is in contrast to the biomedical approach that is based on the positivist and Cartesian models. The paper is an attempt to systematize the similarities and differences between the humanistic approach and the modern biomedical model, which, despite the apparent differences, do not differ so much from each other. Work with a person disabled intellectually in the severe or profound degree is governed by the principles of methodical realism, taking into account to an equal extent the principal deficits, the concomitant diseases, limitations and the social context. The deeper the impairment and disability is, the smaller is the role of the humanistic paradigm in work with the client in the medical management and educational process. Changing the paradigms of special pedagogy has drawn attention to the social context of disability, separating, however, special pedagogy from modern medicine and psychology, cognitive-oriented and psychometry-based. The postmodern paradigm has become an ideology, which makes it difficult to work with deeply disabled people. Only the multidirectional approach including a variety of paradigms makes it possible to provide integrational aid to people with severe and profound grade intellectual disabilities. Working with such a disabled person should take into account equally the biomedical and humanistic aspects. © 2018 MEDPRESS.

Realism in Exercises

DTIC Science & Technology

1989-09-01

me expand on this thesis just a bit. My contention is that in every exercise, even the ones like Wintex- Cimex which are supposed to test the logistics...Wintex- Cimex and Gallant Eagle, occur every other year and in the off-year there is a complimentary FTX. Addit-ionally, there is usually one big CPX...spares calculations, and other logistics concerns. 3-2 Observation and Participation The researcher observed the winter exercise known as Wintex- Cimex

Critical Aesthetic Realism

ERIC Educational Resources Information Center

McMahon, Jennifer A.

2011-01-01

A clear-cut concept of the aesthetic is elusive. Kant's "Critique of Judgment" presents one of the more comprehensive aesthetic theories from which one can extract a set of features, some of which pertain to aesthetic experience and others to the logical structure of aesthetic judgment. When considered together, however, these features present a…

Disarmament and Realism

ERIC Educational Resources Information Center

Smith, Ralph Stuart

1970-01-01

International cooperation in the field of disarmament is necessary to make the world a safe place in which to live. Moreover, every additional advance in aerospace technology makes this cooperation more imperative. (CK)

Effects of Field of View and Visual Complexity on Virtual Reality Training Effectiveness for a Visual Scanning Task

DOE PAGES

Ragan, Eric D.; Bowman, Doug A.; Kopper, Regis; ...

2015-02-13

Virtual reality training systems are commonly used in a variety of domains, and it is important to understand how the realism of a training simulation influences training effectiveness. The paper presents a framework for evaluating the effects of virtual reality fidelity based on an analysis of a simulation’s display, interaction, and scenario components. Following this framework, we conducted a controlled experiment to test the effects of fidelity on training effectiveness for a visual scanning task. The experiment varied the levels of field of view and visual realism during a training phase and then evaluated scanning performance with the simulator’s highestmore » level of fidelity. To assess scanning performance, we measured target detection and adherence to a prescribed strategy. The results show that both field of view and visual realism significantly affected target detection during training; higher field of view led to better performance and higher visual realism worsened performance. Additionally, the level of visual realism during training significantly affected learning of the prescribed visual scanning strategy, providing evidence that high visual realism was important for learning the technique. The results also demonstrate that task performance during training was not always a sufficient measure of mastery of an instructed technique. That is, if learning a prescribed strategy or skill is the goal of a training exercise, performance in a simulation may not be an appropriate indicator of effectiveness outside of training—evaluation in a more realistic setting may be necessary.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ragan, Eric D.; Bowman, Doug A.; Kopper, Regis

Virtual reality training systems are commonly used in a variety of domains, and it is important to understand how the realism of a training simulation influences training effectiveness. The paper presents a framework for evaluating the effects of virtual reality fidelity based on an analysis of a simulation’s display, interaction, and scenario components. Following this framework, we conducted a controlled experiment to test the effects of fidelity on training effectiveness for a visual scanning task. The experiment varied the levels of field of view and visual realism during a training phase and then evaluated scanning performance with the simulator’s highestmore » level of fidelity. To assess scanning performance, we measured target detection and adherence to a prescribed strategy. The results show that both field of view and visual realism significantly affected target detection during training; higher field of view led to better performance and higher visual realism worsened performance. Additionally, the level of visual realism during training significantly affected learning of the prescribed visual scanning strategy, providing evidence that high visual realism was important for learning the technique. The results also demonstrate that task performance during training was not always a sufficient measure of mastery of an instructed technique. That is, if learning a prescribed strategy or skill is the goal of a training exercise, performance in a simulation may not be an appropriate indicator of effectiveness outside of training—evaluation in a more realistic setting may be necessary.« less

A rapid alternative to X-ray crystallography for chiral determination: case studies of vibrational circular dichroism (VCD) to advance drug discovery projects.

PubMed

Wesolowski, Steven S; Pivonka, Don E

2013-07-15

The absolute stereochemistry of chiral drugs is usually established via X-ray crystallography. However, vibrational circular dichroism (VCD) spectroscopy coupled with quantum mechanics simulations offers a rapid alternative to crystallography and is readily applied to both crystalline and non-crystalline samples. VCD is an effective complement to X-ray analysis of drug candidates, and it can be used as a high-throughput means of assessing absolute stereochemistry at all phases of the discovery process (hundreds of assignments per year). The practical implementation (or fee-for-service outsourcing) of VCD and selected case studies are illustrated with an emphasis on providing utility and impact to pharmaceutical discovery programs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Conformational arm-wrestling: battles for stereochemical control in benzamides bearing matched and mismatched chiral 2- and 6-substituents.

PubMed

Clayden, Jonathan; Foricher, Yann J Y; Helliwell, Madeleine; Johnson, Paul; Mitjans, David; Vinader, Victoria

2006-02-07

The orientation of a tertiary amide group adjacent to an aromatic ring may be governed by the stereochemistry of an adjacent chiral substituent. With a chiral substituent in both ortho positions, matched/mismatched pairs of isomers result. Evidence for matched stereochemistry is provided by the clean NMR spectra of single conformers, while mismatching gives poor or unexpected selectivities in the formation of chiral substituents, or mixtures of amide conformers. Attempts to use the match-mismatch effect to select for racemic pairs of enantiomeric substituents, and hence develop a "racemate-sequestering" reagent, are described, along with the use of "matching" to scavenge a single enantiomer of a diamine from material of incomplete enantiomeric purity.

Audience Activity and Television News Gratifications.

ERIC Educational Resources Information Center

Rubin, Alan M.; Perse, Elizabeth M.

1987-01-01

Indicates that (1) affinity, selectivity, and involvement predicted intentionality; (2) pass time motives, perceived realism, and reduced intentionality predicted nonselectivity; (3) pass time motives and reduced affinity predicted distractions; (4) information and nonentertainment motives, perceived realism, and intentionality predicted…

Stereochemical studies of acyclic isoprenoids-XII. Lipids of methanogenic bacteria and possible contributions to sediments

USGS Publications Warehouse

Risatti, J.B.; Rowland, S.J.; Yon, D.A.; Maxwell, J.R.

1984-01-01

Abundant volatile lipids of Methanobacterium thermoautotrophicum and Methanosarcina barkeri include isoprenoid hydrocarbons (??? C30), and C15, C20 and C25 isoprenoid alcohols. M. barkeri contains 2,6,10,15,19-pentamethyleicosane, whose relative stereochemistry is the same as found in marine sediments, indicating that it is a marker of methanogenic activity. The C20, C30 and C25 alkenes in M. thermoautotrophicum also have a preferred sterochemistry; the latter have the 2,6,10,14,18-pentamethyleicosanyl skeleton, suggesting that the alkane in marine sediments may derive from methanogens. The stereochemistry of squalane in a marine sediment is also compatible with an origin in methanogens; in contrast, the stereochemistry of pristane in M. thermoautotrophicum indicates a fossil fuel contaminant origin, suggesting that this and certain other alkanes reported in archaebacteria might also be of contaminant origin. There is, therefore, little evidence at present that the pristane in immature marine sediments originates in methanogens. The C15 and C20 saturated alcohols in M. thermoautotrophicum have mainly the all-R configuration. If this is generally true for methanogens, the C20 alcohol in the Messel shale may originate mainly from methanogens, whereas that in the Green River shale may originate mainly from photosynthetic organisms. ?? 1984.

Tunneling and Parity Violation in Trisulfane (HSSSH): An Almost Ideal Molecule for Detecting Parity Violation in Chiral Molecules.

PubMed

Fábri, Csaba; Horný, Ľuboš; Quack, Martin

2015-12-01

Measuring the parity-violating energy difference Δpv E between the enantiomers of chiral molecules is a major challenge of current physical-chemical stereochemistry. An important step towards this goal is to identify suitable molecules for such experiments by means of theory. This step has been made by calculations for the complex dynamics of tunneling and electroweak quantum chemistry of parity violation in the "classic" molecule trisulfane, HSSSH, which satisfies the relevant conditions for experiments almost ideally, as the molecule is comparatively simple and parity violation clearly dominates over tunneling in the ground state. At the same time, the barrier for stereomutation is easily overcome by the S-H infrared chromophore. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phenomenological Modeling of Infrared Sources: Recent Advances

NASA Technical Reports Server (NTRS)

Leung, Chun Ming; Kwok, Sun (Editor)

1993-01-01

Infrared observations from planned space facilities (e.g., ISO (Infrared Space Observatory), SIRTF (Space Infrared Telescope Facility)) will yield a large and uniform sample of high-quality data from both photometric and spectroscopic measurements. To maximize the scientific returns of these space missions, complementary theoretical studies must be undertaken to interpret these observations. A crucial step in such studies is the construction of phenomenological models in which we parameterize the observed radiation characteristics in terms of the physical source properties. In the last decade, models with increasing degree of physical realism (in terms of grain properties, physical processes, and source geometry) have been constructed for infrared sources. Here we review current capabilities available in the phenomenological modeling of infrared sources and discuss briefly directions for future research in this area.

Struggling for a New Identity: A Critique of the Curriculum Research Effort in Technology Education.

ERIC Educational Resources Information Center

Zuga, Karen F.

Historically, technology education evolved from several strands: Bacon's realism, Pestalozzi's belief in the practical application of knowledge, Rousseau's naturalism, Herbart's sense realism, Dewey's progressive and social reconstructionist thinking, and the influence of vocationalism. The mainstream practice of industrial arts was more a study…

Gold-catalyzed and N-iodosuccinimide-mediated cyclization of gamma-substituted allenamides.

PubMed

Hyland, Christopher J T; Hegedus, Louis S

2006-10-27

Chiral gamma-substituted allenamides have been shown to undergo efficient gold-catalyzed and N-iodosuccinimide-mediated cyclization to highly functionalized dihydrofurans. These reactions proceed rapidly and without loss of stereochemistry.

The effect of maturation on the configuration of pristane in sediments and petroleum

NASA Technical Reports Server (NTRS)

Patience, R. L.; Rowland, S. J.; Maxwell, J. R.

1978-01-01

The absolute stereochemistry of pristane in a sample of contemporary marine zooplankton, Messel shale (Germany) and Djatibarang (Java) crude has been determined by gas chromatographic methods. The relative stereochemistry in Irati shale (Brazil), Green River (U.S.) crude, Halibut (Australia) crude has also been determined, and confirmed for a sample of the Green River shale. The stereoisomer distributions indicate a loss of stereospecificity of the phytol-derived 6(R), 10(S) pristane with increasing geological maturation. For example, the least mature geological sample, the Eocene Messel shale, contains solely the 6(R), 10(S) isomer, whereas a mature sample, Djatibarange crude, contains 50% of the 6(R), 10(S) isomer and 25% of each of the 6(R), 10(R) and 6(S), 10(S) isomers.

Stage acoustics for musicians: A multidimensional approach using 3D ambisonic technology

NASA Astrophysics Data System (ADS)

Guthrie, Anne

In this research, a method was outlined and tested for the use of 3D Ambisonic technology to inform stage acoustics research and design. Stage acoustics for musicians as a field has yet to benefit from recent advancements in auralization and spatial acoustic analysis. This research attempts to address common issues in stage acoustics: subjective requirements for performers in relation to feelings of support, quality of sound, and ease of ensemble playing in relation to measurable, objective characteristics that can be used to design better stage enclosures. While these issues have been addressed in previous work, this research attempts to use technological advancements to improve the resolution and realism of the testing and analysis procedures. Advancements include measurement of spatial impulse responses using a spherical microphone array, higher-order ambisonic encoding and playback for real-time performer auralization, high-resolution spatial beamforming for analysis of onstage impulse responses, and multidimensional scaling procedures to determine subjective musician preferences. The methodology for implementing these technologies into stage acoustics research is outlined in this document and initial observations regarding implications for stage enclosure design are proposed. This research provides a robust method for measuring and analyzing performer experiences on multiple stages without the costly and time-intensive process of physically surveying orchestras on different stages, with increased repeatability while maintaining a high level of immersive realism and spatial resolution. Along with implications for physical design, this method provides possibilities for virtual teaching and rehearsal, parametric modeling and co-located performance.

Exposure Render: An Interactive Photo-Realistic Volume Rendering Framework

PubMed Central

Kroes, Thomas; Post, Frits H.; Botha, Charl P.

2012-01-01

The field of volume visualization has undergone rapid development during the past years, both due to advances in suitable computing hardware and due to the increasing availability of large volume datasets. Recent work has focused on increasing the visual realism in Direct Volume Rendering (DVR) by integrating a number of visually plausible but often effect-specific rendering techniques, for instance modeling of light occlusion and depth of field. Besides yielding more attractive renderings, especially the more realistic lighting has a positive effect on perceptual tasks. Although these new rendering techniques yield impressive results, they exhibit limitations in terms of their exibility and their performance. Monte Carlo ray tracing (MCRT), coupled with physically based light transport, is the de-facto standard for synthesizing highly realistic images in the graphics domain, although usually not from volumetric data. Due to the stochastic sampling of MCRT algorithms, numerous effects can be achieved in a relatively straight-forward fashion. For this reason, we have developed a practical framework that applies MCRT techniques also to direct volume rendering (DVR). With this work, we demonstrate that a host of realistic effects, including physically based lighting, can be simulated in a generic and flexible fashion, leading to interactive DVR with improved realism. In the hope that this improved approach to DVR will see more use in practice, we have made available our framework under a permissive open source license. PMID:22768292

An Easily Constructed Model of a Coordination Polyhedron that Represents the Hexagonal Closest-Packed Structure.

ERIC Educational Resources Information Center

Yamana, Shukichi

1987-01-01

Illustrates the 29 steps involved in the development of a model of a coordination polyhedron that represents the hexagonal closest packed structure. Points out it is useful in teaching stereochemistry. (TW)

48 CFR 5215.605 - Evaluation factors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... appropriate premiums for measured increments of quality. When a cost/benefit approach is used, cost must carry... recent Forward Pricing Rate Agreements (FPRAs)). (iv) Cost realism evaluation generally will be performed... realism data are required, the contracting officer shall not request a formal field pricing report but...

An Evaluation of Student Perceptions of Screen Presentations in Computer-based Laboratory Simulations.

ERIC Educational Resources Information Center

Edward, Norrie S.

1997-01-01

Evaluates the importance of realism in the screen presentation of the plant in computer-based laboratory simulations for part-time engineering students. Concludes that simulations are less effective than actual laboratories but that realism minimizes the disadvantages. The schematic approach was preferred for ease of use. (AIM)

Somewhere between What Is and What If: Fictionalisation and Ethnographic Inquiry

ERIC Educational Resources Information Center

Reed, Malcolm

2011-01-01

Fictionalisation seems to render ethnographic inquiry suspect as research appropriate to the social sciences because it subverts a claim of realism or objectivity. This leads some ethnographers to propose alternative criteria for validation, such as participation and evocation, which offer alignment with realism; others suggest that scientific…

A linearized theory method of constrained optimization for supersonic cruise wing design

NASA Technical Reports Server (NTRS)

Miller, D. S.; Carlson, H. W.; Middleton, W. D.

1976-01-01

A linearized theory wing design and optimization procedure which allows physical realism and practical considerations to be imposed as constraints on the optimum (least drag due to lift) solution is discussed and examples of application are presented. In addition to the usual constraints on lift and pitching moment, constraints are imposed on wing surface ordinates and wing upper surface pressure levels and gradients. The design procedure also provides the capability of including directly in the optimization process the effects of other aircraft components such as a fuselage, canards, and nacelles.

The probabilistic origin of Bell's inequality

NASA Technical Reports Server (NTRS)

Krenn, Guenther

1994-01-01

The concept of local realism entails certain restrictions concerning the possible occurrence of correlated events. Although these restrictions are inherent in classical physics they have never been noticed until Bell showed in 1964 that general correlations in quantum mechanics can not be interpreted in a classical way. We demonstrate how a local realistic way of thinking about measurement results necessarily leads to limitations with regard to the possible appearance of correlated events. These limitations, which are equivalent to Bell's inequality can be easily formulated as an immediate consequence of our discussion.

A Hilbert Space Representation of Generalized Observables and Measurement Processes in the ESR Model

NASA Astrophysics Data System (ADS)

Sozzo, Sandro; Garola, Claudio

2010-12-01

The extended semantic realism ( ESR) model recently worked out by one of the authors embodies the mathematical formalism of standard (Hilbert space) quantum mechanics in a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide here a Hilbert space representation of the generalized observables introduced by the ESR model that satisfy a simple physical condition, propose a generalization of the projection postulate, and suggest a possible mathematical description of the measurement process in terms of evolution of the compound system made up of the measured system and the measuring apparatus.

Delayed-Choice Experiments and the Metaphysics of Entanglement

NASA Astrophysics Data System (ADS)

Egg, Matthias

2013-09-01

Delayed-choice experiments in quantum mechanics are often taken to undermine a realistic interpretation of the quantum state. More specifically, Healey has recently argued that the phenomenon of delayed-choice entanglement swapping is incompatible with the view that entanglement is a physical relation between quantum systems. This paper argues against these claims. It first reviews two paradigmatic delayed-choice experiments and analyzes their metaphysical implications. It then applies the results of this analysis to the case of entanglement swapping, showing that such experiments pose no threat to realism about entanglement.

Mechanism and Stereochemistry of 5-Dehydroquinate Synthetase*

PubMed Central

Rotenberg, S. L.; Sprinson, D. B.

1970-01-01

3-Deoxy-D-arabino-heptulosonic acid 7-phosphate (DAHP) labeled at C-7 randomly or stereospecifically with tritium and at C-1 with 14C was converted enzymically to 5-dehydroquinate. Tritium of all three substrates was completely retained in 5-dehydroquinate, in accord with formation of a non-ketonizing 6,7-enol intermediate. The 5-dehydroquinates were dehydrated to 5-dehydroshikimate by 5-dehydroquinate dehydratase, which is known to catalyze a cis-elimination. Only 5-dehydroquinate derived from [7-3H](7R)-DAHP lost its tritium in this dehydration, indicating that the configuration at C-7 was inverted in the conversion of DAHP to 5-dehydroquinate. PMID:5275368

How Stereochemistry Considerations can Improve Pesticide Safety

EPA Science Inventory

About 30% of pesticides are chiral molecules and therefore exist as two or more stereoisomers, which can differ significantly in their toxicity, biodegradation, and persistence. Such differences can impact their relative safety to humans and environmental species. Enantiomers, mi...

Stereochemistry of silicon in oxygen-containing compounds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serezhkin, V. N., E-mail: Serezhkin@samsu.ru; Urusov, V. S.

2017-01-15

Specific stereochemical features of silicon in oxygen-containing compounds, including hybrid silicates with all oxygen atoms of SiO{sub n} groups ({sub n} = 4, 5, or 6) entering into the composition of organic anions or molecules, are described by characteristics of Voronoi—Dirichlet polyhedra. It is found that in rutile-like stishovite and post-stishovite phases with the structures similar to those of СаСl{sub 2}, α-PbO{sub 2}, or pyrite FeS{sub 2}, the volume of Voronoi—Dirichlet polyhedra of silicon and oxygen atoms decreases linearly with pressure increasing to 268 GPa. Based on these results, the possibility of formation of new post-stishovite phases is shown, namely,more » the fluorite-like structure (transition predicted at ~400 GPa) and a body-centered cubic lattice with statistical arrangement of silicon and oxygen atoms (~900 GPa).« less

Antiviral agents of plant origin. III. Scopadulin, a novel tetracyclic diterpene from Scoparia dulcis L.

PubMed

Hayashi, T; Kawasaki, M; Miwa, Y; Taga, T; Morita, N

1990-04-01

The structure and stereochemistry of scopadulin, a novel aphidicolane-type diterpene isolated from Scoparia dulcis L. have been established from spectral data and single-crystal X-ray analysis of its acetone solvate.

Chemical Applications of Graph Theory: Part I. Fundamentals and Topological Indices.

ERIC Educational Resources Information Center

Hansen, Peter J.; Jurs, Peter C.

1988-01-01

Explores graph theory and use of topological indices to predict boiling points. Lists three indices: Wiener Number, Randic Branching Index and Molecular Connectivity, and Molecular Identification numbers. Warns of inadequacies with stereochemistry. (ML)

Representational Realism, Closed Theories and the Quantum to Classical Limit

NASA Astrophysics Data System (ADS)

de Ronde, Christian

In this chapter, we discuss the representational realist stance as a pluralistontic approach to inter-theoretic relationships. Our stance stresses the fact that physical theories require the necessary consideration of a conceptual level of discourse which determines and configures the specific field of phenomena discussed by each particular theory. We will criticize the orthodox line of research which has grounded the analysis about QM in two (Bohrian) metaphysical presuppositions - accepted in the present as dogmas that all interpretations must follow. We will also examine how the orthodox project of "bridging the gap" between the quantum and the classical domains has constrained the possibilities of research, producing only a limited set of interpretational problems which only focus in the justification of "classical reality" and exclude the possibility of analyzing the possibilities of non-classical conceptual representations of QM. The representational realist stance introduces two new problems, namely, the superposition problem and the contextuality problem, which consider explicitly the conceptual representation of orthodox QM beyond the mere reference to mathematical structures and measurement outcomes. In the final part of the chapter, we revisit, from representational realist perspective, the quantum to classical limit and the orthodox claim that this inter-theoretic relation can be explained through the principle of decoherence.

Weird Reality, Aesthetics, and Vitality in Education

ERIC Educational Resources Information Center

Oral, Sevket Benhur

2015-01-01

This paper discusses the repercussions of a new metaphysics--speculative/weird realism--for education and pedagogy. A historic shift is taking place in present-day continental philosophy, which involves an explicit and renewed call for "realism." One of the most salient features of this development is a revitalised interest in…

What's Really Wrong with Ethnography?

ERIC Educational Resources Information Center

Banfield, Grant

2004-01-01

In asking the provocative question: "What's wrong with ethnography?" Hammersley draws attention to what he sees as the conceptual and methodological confusion arising from two competing strands of practice: "naive realism" and "relativism". As a solution, he offers "subtle realism" to steer a path through and beyond the confusion. This paper…

The Canvas Mirror: Painting as Politics in the New Deal.

ERIC Educational Resources Information Center

Fogel, Jared A.; Stevens, Robert L.

2001-01-01

Explores four artistic classifications prominent in depression-era art examining and contrasting examples of each: (1) Regionalism; (2) Social Realism; (3) American Idealism; and (4) Anti-Fascism. Focuses on artworks by the artist Seymour Fogel because his work demonstrates that Regionalism and Social Realism were not mutually exclusive and that…

A Critical Realist Orientation to Learner Needs

ERIC Educational Resources Information Center

Ayers, David F.

2011-01-01

The objective of this essay is to propose critical realism as a philosophical middle way between two sets of ontological, epistemological, and methodological assumptions regarding learner needs. Key concepts of critical realism, a tradition in the philosophy of science, are introduced and applied toward an analysis of learner needs, resulting in…

Policy prescriptions to preserve mobility for seniors--A dose of realism.

PubMed

Staplin, Loren; Freund, Katherine

2013-12-01

This paper advocates policy change in three key areas: infrastructure, driver licensing, and access to private resources for transportation alternatives. Policy makers are encouraged to plan for the transportation future of our aging society by prioritizing public expenditures for roads and highways according to design and engineering practices already proven to assist older drivers and pedestrians. By adopting minimum, evidence-based requirements for visual, mental and physical capability for licensure and uniformly applying them at all ages, across all states, policy makers can improve the safety of older drivers without unfairly restricting their mobility-and need not increase the regulatory burden in doing so. By reviewing and replicating already successful state policies that either create incentives or remove barriers to the use of private resources for non-profit, senior transportation, policy makers can help communities access the labor and capital, as well as manage the risks of market-oriented, non-profit mobility solutions. Copyright © 2013 Elsevier Ltd. All rights reserved.

The reasonable effectiveness of mathematics in the natural sciences

NASA Astrophysics Data System (ADS)

Harvey, Alex

2011-12-01

Mathematics and its relation to the physical universe have been the topic of speculation since the days of Pythagoras. Several different views of the nature of mathematics have been considered: Realism—mathematics exists and is discovered; Logicism—all mathematics may be deduced through pure logic; Formalism—mathematics is just the manipulation of formulas and rules invented for the purpose; Intuitionism—mathematics comprises mental constructs governed by self evident rules. The debate among the several schools has major importance in understanding what Eugene Wigner called, The Unreasonable Effectiveness of Mathematics in the Natural Sciences. In return, this `Unreasonable Effectiveness' suggests a possible resolution of the debate in favor of Realism. The crucial element is the extraordinary predictive capacity of mathematical structures descriptive of physical theories.

Transmission of chirality through space and across length scales

NASA Astrophysics Data System (ADS)

Morrow, Sarah M.; Bissette, Andrew J.; Fletcher, Stephen P.

2017-05-01

Chirality is a fundamental property and vital to chemistry, biology, physics and materials science. The ability to use asymmetry to operate molecular-level machines or macroscopically functional devices, or to give novel properties to materials, may address key challenges at the heart of the physical sciences. However, how chirality at one length scale can be translated to asymmetry at a different scale is largely not well understood. In this Review, we discuss systems where chiral information is translated across length scales and through space. A variety of synthetic systems involve the transmission of chiral information between the molecular-, meso- and macroscales. We show how fundamental stereochemical principles may be used to design and understand nanoscale chiral phenomena and highlight important recent advances relevant to nanotechnology. The survey reveals that while the study of stereochemistry on the nanoscale is a rich and dynamic area, our understanding of how to control and harness it and dial-up specific properties is still in its infancy. The long-term goal of controlling nanoscale chirality promises to be an exciting journey, revealing insight into biological mechanisms and providing new technologies based on dynamic physical properties.

Novel stereocontrolled approach to syn- and anti-oxepene-cyclogeranyl trans-fused polycyclic systems: asymmetric total synthesis of (-)-Aplysistatin, (+)-Palisadin A, (+)-Palisadin B, (+)-12-hydroxy-palisadin B, and the AB ring system of adociasulfate-2 and toxicol A.

PubMed

Couladouros, Elias A; Vidali, Veroniki P

2004-08-06

A new stereocontrolled method for the formation of trans-anti cyclogeranyl-oxepene systems is described. The demanding stereochemistry is secured by stereoselective coupling of a cyclogeranyl tertiary alcohol with a 1,2-unsymmetrically substituted epoxide, while the formation of the highly strained oxepene is achieved employing ring-closing metathesis. Since the stereochemistry of the trans-fused 6,7-ring system is determined by the epoxide, the method also allows the construction of trans-syn 6,7-ring systems. This approach leads to the synthesis of the AB fragment of Adociasulfate-2 and Toxicol A, for the first time. The flexibility and efficiency of the presented strategy is demonstrated by the total asymmetric synthesis of (-)-Aplysistatin, (+)-Palisadin A, (+)-12-hydroxy-Palisadin B, and (+)-Palisadin B, employing two similar key intermediates.

An Easily Constructed Model of a Coordination Polyhedron that Represents the Cubic Closest-Packed Structure.

ERIC Educational Resources Information Center

Yamana, Shukichi

1987-01-01

Illustrates the 18 steps to the development of a model of a coordination polyhedron that represents the cubic closest-packed structure. Uses a sealed, empty envelope in developing the model in teaching about stereochemistry. (TW)

Teaching 1H NMR Spectrometry Using Computer Modeling.

ERIC Educational Resources Information Center

Habata, Yoichi; Akabori, Sadatoshi

2001-01-01

Molecular modeling by computer is used to display stereochemistry, molecular orbitals, structure of transition states, and progress of reactions. Describes new ideas for teaching 1H NMR spectroscopy using computer modeling. (Contains 12 references.) (ASK)

Hydrological modelling over different scales on the edge of the permafrost zone: approaching model realism based on experimentalists' knowledge

NASA Astrophysics Data System (ADS)

Nesterova, Natalia; Makarieva, Olga; Lebedeva, Lyudmila

2017-04-01

of river runoff, snow depth, soil temperature and moisture in the Mogot study site are satisfactory. Model parameterization developed on the Mogot watersheds was employed to simulate runoff generation in the four river basins with area from 150 to 4060 km2 in the surrounded region. We conclude that data about internal catchment processes is extremely helpful for the increasing model realism. Hard and soft experimental knowledge in the form of model parameters and settings could be transferred to larger river basins in the region. The study is supported by Russian Foundation for Basic Research (project 15-35-21146).

Diazo compounds in the chemistry of fullerenes

NASA Astrophysics Data System (ADS)

Tuktarov, Airat R.; Dzhemilev, Usein M.

2010-09-01

Experimental and theoretical data on the reactions of different diazo compounds (diazomethane, its derivatives, cyclic diazo compounds and diazocarbonyl compounds) with fullerenes are summarized. The structures and stereochemistry of cycloadducts formed in these reactions are considered.

Conditions for Lorentz-invariant superluminal information transfer without signaling

NASA Astrophysics Data System (ADS)

Grössing, G.; Fussy, S.; Mesa Pascasio, J.; Schwabl, H.

2016-03-01

We understand emergent quantum mechanics in the sense that quantum mechanics describes processes of physical emergence relating an assumed sub-quantum physics to macroscopic boundary conditions. The latter can be shown to entail top-down causation, in addition to usual bottom-up scenarios. With this example it is demonstrated that definitions of “realism” in the literature are simply too restrictive. A prevailing manner to define realism in quantum mechanics is in terms of pre-determination independent of the measurement. With our counter-example, which actually is ubiquitous in emergent, or self-organizing, systems, we argue for realism without pre-determination. We refer to earlier results of our group showing how the guiding equation of the de Broglie-Bohm interpretation can be derived from a theory with classical ingredients only. Essentially, this corresponds to a “quantum mechanics without wave functions” in ordinary 3-space, albeit with nonlocal correlations. This, then, leads to the central question of how to deal with the nonlocality problem in a relativistic setting. We here show that a basic argument discussing the allegedly paradox time ordering of events in EPR-type two-particle experiments falls short of taking into account the contextuality of the experimental setup. Consequently, we then discuss under which circumstances (i.e. physical premises) superluminal information transfer (but not signaling) may be compatible with a Lorentz-invariant theory. Finally, we argue that the impossibility of superluminal signaling - despite the presence of superluminal information transfer - is not the result of some sort of conspiracy (á la “Nature likes to hide”), but the consequence of the impossibility to exactly reproduce in repeated experimental runs a state's preparation, or of the no-cloning theorem, respectively.

Bell Test experiments explained without entanglement

NASA Astrophysics Data System (ADS)

Boyd, Jeffrey

2011-04-01

by Jeffrey H. Boyd. Jeffreyhboyd@gmail.com. John Bell proposed a test of what was called "local realism." However that is a different view of reality than we hold. Bell incorrectly assumed the validity of wave particle dualism. According to our model waves are independent of particles; wave interference precedes the emission of a particle. This results in two conclusions. First the proposed inequalities that apply to "local realism" in Bell's theorem do not apply to this model. The alleged mathematics of "local realism" is therefore wrong. Second, we can explain the Bell Test experimental results (such as the experiments done at Innsbruck) without any need for entanglement, non-locality, or particle superposition.

Views about Physics Held by Physics Teachers with Differing Approaches to Teaching Physics

ERIC Educational Resources Information Center

Mulhall, Pamela; Gunstone, Richard

2008-01-01

Physics teachers' approaches to teaching physics are generally considered to be linked to their views about physics. In this qualitative study, the views about physics held by a group of physics teachers whose teaching practice was traditional were explored and compared with the views held by physics teachers who used conceptual change approaches.…

Beyond Iconic Simulation

ERIC Educational Resources Information Center

Dormans, Joris

2011-01-01

Realism remains a prominent topic in game design and industry research; yet, a strong academic case can be made that games are anything, but realistic. This article frames realism in games in semiotic terms as iconic simulation and argues that games can gain expressiveness when they move beyond the current focus on iconic simulation. In parallel…

Analysing an Audit Cycle: A Critical Realist Account

ERIC Educational Resources Information Center

Boughey, Chrissie; McKenna, Sioux

2017-01-01

This paper reports on the use of a framework developed from Bhaskar's critical realism and Archer's social realism to analyse teaching- and learning-related data produced as a result of the first cycle of institutional audits in the South African higher education system. The use of the framework allows us to see what this cycle of audits did…

Total synthesis and stereochemical assignment of the spiroisoxazoline natural product (+)-calafianin.

PubMed

Bardhan, Sujata; Schmitt, Daniel C; Porco, John A

2006-03-02

Synthesis of the spiroisoxazoline natural product (+)-calafianin is reported using asymmetric nucleophilic epoxidation and nitrile oxide cycloaddition as key steps. Synthesis and spectral analysis of all calafianin stereoisomers led to unambiguous assignment of relative and absolute stereochemistry.

A single active site residue directs oxygenation stereospecificity in lipoxygenases: Stereocontrol is linked to the position of oxygenation

PubMed Central

Coffa, Gianguido; Brash, Alan R.

2004-01-01

Lipoxygenases are a class of dioxygenases that form hydroperoxy fatty acids with distinct positional and stereo configurations. Several amino acid residues influencing regiospecificity have been identified, whereas the basis of stereocontrol is not understood. We have now identified a single residue in the lipoxygenase catalytic domain that is important for stereocontrol; it is conserved as an Ala in S lipoxygenases and a Gly in R lipoxygenases. Our results with mutation of the conserved Ala to Gly in two S lipoxygenases (mouse 8S-LOX and human 15-LOX-2) and the corresponding Gly–Ala substitution in two R lipoxygenases (human 12R-LOX and coral 8R-LOX) reveal that the basis for R or S stereo-control also involves a switch in the position of oxygenation on the substrate. After the initial hydrogen abstraction, antarafacial oxygenation at one end or the other of the activated pair of double bonds (pentadiene) gives, for example, 8S or 12R product. The Ala residue promotes oxygenation on the reactive pentadiene at the end deep in the substrate binding pocket and S stereochemistry of the product hydroperoxide, and a Gly residue promotes oxygenation at the proximal end of the reactive pentadiene resulting in R stereochemistry. A model of lipoxygenase reaction specificity is proposed in which product regiochemistry and stereochemistry are determined by fixed relationships between substrate orientation, hydrogen abstraction, and the Gly or Ala residue we have identified. PMID:15496467

European Physical Society Conference on High Energy Physics

NASA Astrophysics Data System (ADS)

The European Physical Society Conference on High Energy Physics, organized by the High Energy and Particle Physics Division of the European Physical Society, is a major international conference that reviews biennially since 1971 the state of our knowledge of the fundamental constituents of matter and their interactions. The latest conferences in this series were held in Stockholm, Grenoble, Krakow, Manchester, Lisbon, and Aachen. Jointly organized by the Institute of High Energy Physics of the Austrian Academy of Sciences, the University of Vienna, the Vienna University of Technology, and the Stefan Meyer Institute for Subatomic Physics of the Austrian Academy of Sciences, the 23rd edition of this conference took place in Vienna, Austria. Among the topics covered were Accelerators, Astroparticle Physics, Cosmology and Gravitation, Detector R&D and Data Handling, Education and Outreach, Flavour Physics and Fundamental Symmetries, Heavy Ion Physics, Higgs and New Physics, Neutrino Physics, Non-Perturbative Field Theory and String Theory, QCD and Hadronic Physics, as well as Top and Electroweak Physics.

Guajadial: an unusual meroterpenoid from guava leaves Psidium guajava.

PubMed

Yang, Xiao-Long; Hsieh, Kun-Lung; Liu, Ji-Kai

2007-11-22

Guajadial (1), a novel caryophyllene-based meroterpenoid, was isolated from the Leaves of Psidium guajava (guava). The structure and relative stereochemistry of guajadial (1) were elucidated by extensive spectroscopic analysis. A possible biosynthetic pathway for 1 was proposed.

Hardy's test as a device-independent dimension witness

NASA Astrophysics Data System (ADS)

Mukherjee, Amit; Roy, Arup; Bhattacharya, Some Sankar; Das, Subhadipa; Gazi, Md. Rajjak; Banik, Manik

2015-08-01

Knowing the dimension of an unknown physical system has practical relevance, as dimensionality plays an important role in various information theoretic tasks. In this work we show that a modified version of Hardy's argument, which reveals the contradiction of quantum theory with local realism, turns out to be useful for inspecting the minimal subsystem dimension of an unknown correlated quantum system. The use of Hardy's test in this task has a novel advantage: the subsystem dimension can be determined without knowing the detailed functioning of the experimental devices; i.e., Hardy's test suffices to be a device-independent dimension witness.

China Report, Political, Sociological and Military Affairs

DTIC Science & Technology

1985-02-15

method of writing in the socialist literature of the new period; basically, the creative method of revolutionary realism is adopted, such...resolutionary realism regarding revolutionary romanticism as an important component part, and not in the least rejecting the independent existence and...Chinese Cinematic Performing Arts discussion meeting at the Nanhu Guesthouse in Guangzhou on the afternoon of 16 January, Entrusted by Comrade Ren

Modelling the core magnetic field of the earth

NASA Technical Reports Server (NTRS)

Harrison, C. G. A.; Carle, H. M.

1982-01-01

It is suggested that radial off-center dipoles located within the core of the earth be used instead of spherical harmonics of the magnetic potential in modeling the core magnetic field. The off-center dipoles, in addition to more realistically modeling the physical current systems within the core, are if located deep within the core more effective at removing long wavelength signals of either potential or field. Their disadvantage is that their positions and strengths are more difficult to compute, and such effects as upward and downward continuation are more difficult to manipulate. It is nevertheless agreed with Cox (1975) and Alldredge and Hurwitz (1964) that physical realism in models is more important than mathematical convenience. A radial dipole model is presented which agrees with observations of secular variation and excursions.

Medical physics: the perfect intermediate level physics class

NASA Astrophysics Data System (ADS)

Christensen, Nelson

2001-07-01

Medical physics is currently a rapidly growing field of physics. Numerous academic, clinical and industrial opportunities are open to physicists in the medical world. I report on an intermediate level physics course on medical physics taught at Carleton College. The topics covered in this course cover all areas of physics, but with examples drawn from medical applications. In addition to physics majors, this course appeals to biology, chemistry and pre-medical students who have a keen interest in physics.

Demonstration of Enantiomer Specificity of Proteins and Drugs

ERIC Educational Resources Information Center

Anderson, Gretchen L.; Page, Shallee T.

2004-01-01

Classroom demonstrations and activities are used to illustrate the properties of enantiomer. During this activity, in a relatively short time students develop a working knowledge of the importance of stereochemistry in biochemistry and its effect on drug design and metabolism.

iMarNet: an ocean biogeochemistry model intercomparison project within a common physical ocean modelling framework

NASA Astrophysics Data System (ADS)

Kwiatkowski, L.; Yool, A.; Allen, J. I.; Anderson, T. R.; Barciela, R.; Buitenhuis, E. T.; Butenschön, M.; Enright, C.; Halloran, P. R.; Le Quéré, C.; de Mora, L.; Racault, M.-F.; Sinha, B.; Totterdell, I. J.; Cox, P. M.

2014-12-01

Ocean biogeochemistry (OBGC) models span a wide variety of complexities, including highly simplified nutrient-restoring schemes, nutrient-phytoplankton-zooplankton-detritus (NPZD) models that crudely represent the marine biota, models that represent a broader trophic structure by grouping organisms as plankton functional types (PFTs) based on their biogeochemical role (dynamic green ocean models) and ecosystem models that group organisms by ecological function and trait. OBGC models are now integral components of Earth system models (ESMs), but they compete for computing resources with higher resolution dynamical setups and with other components such as atmospheric chemistry and terrestrial vegetation schemes. As such, the choice of OBGC in ESMs needs to balance model complexity and realism alongside relative computing cost. Here we present an intercomparison of six OBGC models that were candidates for implementation within the next UK Earth system model (UKESM1). The models cover a large range of biological complexity (from 7 to 57 tracers) but all include representations of at least the nitrogen, carbon, alkalinity and oxygen cycles. Each OBGC model was coupled to the ocean general circulation model Nucleus for European Modelling of the Ocean (NEMO) and results from physically identical hindcast simulations were compared. Model skill was evaluated for biogeochemical metrics of global-scale bulk properties using conventional statistical techniques. The computing cost of each model was also measured in standardised tests run at two resource levels. No model is shown to consistently outperform all other models across all metrics. Nonetheless, the simpler models are broadly closer to observations across a number of fields and thus offer a high-efficiency option for ESMs that prioritise high-resolution climate dynamics. However, simpler models provide limited insight into more complex marine biogeochemical processes and ecosystem pathways, and a parallel approach of

JPRS Report, China, Red Flag, Number 9, 1 May 1988

DTIC Science & Technology

1988-07-08

constantly being consummated and deepened. In China as in other countries, writers and artists of classi- cal realism , particularly writers and artists...of modern critical realism , as well as philosophers and aestheticians living in the same age, have all written on the reflection of life in...exhibition, performance, cinematic production, circulation and broadcasting are the main forms of dissemination. There is hardly any author who

An Annotated Bibliography of Objective Pilot Performance Measures

DTIC Science & Technology

1982-01-01

realism . (Author) 224 NAVTRAEQUIPCEN IH-330 t 667. PROPHET, Wallace W., and Caro, Paul W., Simulation and Aircrew Training and Performance, Human... cinematic simulation and air training appears to be the most promising cost-effective method of developing NOE visual perception skills. Of other...flight and control dynamics. Informal trials were run with research staff and carrier-qualified pilots to evaluate realism of the displays; amount of

Streamlining Simulation Development using a Commercial Game Engine

DTIC Science & Technology

2009-10-01

few years. The realism is stunning and the Commercial Game Industry fuels the fire of cutting edge advances in hardware and immersive experiences...Technology applies to Military training in more than just the obvious upgrades in game engines and hardware. The increased visual realism and performance...elaborate storytelling and cinematic effects provide a more immersive and compelling experience to the player. The underlying game engine technology

Physics: Frightful, but Fun. Pupils' and Teachers' Views of Physics and Physics Teaching

ERIC Educational Resources Information Center

Angell, Carl; Guttersrud, Oystein; Henriksen, Ellen K.; Isnes, Anders

2004-01-01

There is widespread concern for the situation of school physics regarding recruitment, contents, teaching methods, etc. In this study based on questionnaire and focus group data, we explore how upper secondary pupils and teachers perceive physics as a subject, how they experience physics instruction, and how physics compares to other subjects. Our…

Do as I do: exercise habits of physical therapists, physical therapist assistants, and student physical therapists.

PubMed

Chevan, Julia; Haskvitz, Esther M

2010-05-01

Physical therapy practitioners are among the many health care professionals who can counsel their patients to address the public health care concern of physical inactivity. Health care providers who are physically active themselves are more likely to counsel patients on the benefits of activity. The purposes of this study were: (1) to examine the leisure-time physical activity habits of physical therapists, physical therapist assistants, and student physical therapists in the United States using Centers for Disease Control and Prevention and American College of Sports Medicine (CDC-ACSM) recommendations and (2) to compare these habits with those of the general population and other health care professionals. A cross-sectional survey design was used. There were 2 data sources. A random sample of American Physical Therapy Association members completed an online survey that included questions about physical activity habits worded in same manner as the leisure-time activities section of the 2005 National Health Interview Survey (NHIS). The final study sample comprised 1,238 participants: 923 physical therapists, 210 student physical therapists, and 105 physical therapist assistants. The 2005 NHIS public use data files were the source for the same information about the general US population and for a subset of health care professionals. Rates of participation in vigorous and moderate physical activity were analyzed. Physical therapists, physical therapist assistants, and student physical therapists exercised at higher rates than adults and health-diagnosing professionals in the 2005 NHIS. Limitations The study may be limited by sampling and response bias. This study identified that physical therapists, physical therapist assistants, and student physical therapists are meeting CDC-ACSM physical activity guidelines at higher rates than the US adult population and health-diagnosing professionals. These rates exceed the physical activity targets set for adults in Healthy

Secoiridoid components from Jasminum grandiflorum.

PubMed

Sadhu, Samir Kumar; Khan, Md Sojib; Ohtsuki, Takashi; Ishibashi, Masami

2007-07-01

Secoiridoid glucosides, 2''-epifraxamoside and demethyl-2''-epifraxamoside, and the secoiridoid, jasminanhydride were isolated from Jasminum grandiflorum together with four previously known phenolics and a triterpene. Structures were elucidated by detailed spectroscopic analysis. Stereochemistry of the compounds was determined by differential NOE experiment.

The Reception of J. H. van't Hoff's Theory of the Asymmetric Carbon Atom

ERIC Educational Resources Information Center

Snelders, H. A. M.

1974-01-01

Discusses Jacobus Henricus van't Hoff's revolutionary theory of the asymmetric carbon atom and its early reception among his contemporaries in the Netherlands. Indicates that the extension of the new idea to practical problems gives the impetus to the development of stereochemistry. (CC)

Philosophy of race meets population genetics.

PubMed

Spencer, Quayshawn

2015-08-01

In this paper, I respond to four common semantic and metaphysical objections that philosophers of race have launched at scholars who interpret recent human genetic clustering results in population genetics as evidence for biological racial realism. I call these objections 'the discreteness objection', 'the visibility objection', 'the very important objection', and 'the objectively real objection.' After motivating each objection, I show that each one stems from implausible philosophical assumptions about the relevant meaning of 'race' or the nature of biological racial realism. In order to be constructive, I end by offering some advice for how we can productively critique attempts to defend biological racial realism based on recent human genetic clustering results. I also offer a clarification of the relevant human-population genetic research. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Metolachlor Herbicide: An Exercise in Today's Stereochemistry

ERIC Educational Resources Information Center

Mannschreck, Albrecht; von Angerer, Erwin

2009-01-01

Metolachlor is one of the most widely used agents registered for the protection of many cultivated plants against weeds. Because of axial and central chirality, this molecule forms four stereoisomers, the investigation of which by [superscript 1]H NMR and chromatography is described. It is shown that the isomers do not interconvert at room…

The "Protocenter" Concept: A Method for Teaching Stereochemistry

ERIC Educational Resources Information Center

Lewis, David E.

2010-01-01

The "protocenter", defined as an atom carrying two different attached groups in a nonlinear arrangement, is proposed as a concept useful for the introduction of chirality and geometric isomerism in introductory organic chemistry classes. Two protocenters are the minimum requirement for stereoisomers of a compound to exist. Protocenters may be…

Stereochemistry Considerations Can Improve Pesticide Safety and Sustainability

EPA Science Inventory

About 30% of pesticides are chiral molecules and therefore exist as two or more stereoisomers, which can differ significantly in their toxicity, biodegradation, and persistence. Such differences determine their relative safety to humans and environmental species. Enantiomers, mir...

Stereochemistry and function of oxaloacetate keto-enol tautomerase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Creighton, D.J.; Johnson, J.D.; Lambert, M.R.

1986-05-01

Oxaloacetate keto-enol tautomerase, partially purified from porcine kidney, catalyzes the conversions of enol- to keto-oxaloacetate by a mechanism in which solvent protons end up equally distributed between the two prochiral positions at C3 of keto-oxaloacetate. This conclusion is based upon the observation that when enzyme catalyzed ketonization is conducted in /sup 3/H/sub 2/O in the presence of excess malate dehydrogenase and NADH, only 50% of the /sup 3/H in the isolated (2S)-(3-/sup 3/H)malate is labilized to solvent upon treatment with fumarase. Either the tautomerase operates on the basis of a highly unusual stereomechanistic principle or tautomerase activity is not anmore » evolved property of the enzyme protein. As a result of an attempt to clarify the physiological importance of oxaloacetate tautomerase activity, keto-oxaloacetate was demonstrated to be directly transported across the inner membrane of rat liver mitochrondria, on the basis of the results of kinetic and isotope-trapping experiments.« less

Close encounters with DNA

PubMed Central

Maffeo, C.; Yoo, J.; Comer, J.; Wells, D. B.; Luan, B.; Aksimentiev, A.

2014-01-01

Over the past ten years, the all-atom molecular dynamics method has grown in the scale of both systems and processes amenable to it and in its ability to make quantitative predictions about the behavior of experimental systems. The field of computational DNA research is no exception, witnessing a dramatic increase in the size of systems simulated with atomic resolution, the duration of individual simulations and the realism of the simulation outcomes. In this topical review, we describe the hallmark physical properties of DNA from the perspective of all-atom simulations. We demonstrate the amazing ability of such simulations to reveal the microscopic physical origins of experimentally observed phenomena and we review the frustrating limitations associated with imperfections of present atomic force fields and inadequate sampling. The review is focused on the following four physical properties of DNA: effective electric charge, response to an external mechanical force, interaction with other DNA molecules and behavior in an external electric field. PMID:25238560

Coordination of knowledge in judging animated motion

NASA Astrophysics Data System (ADS)

Thaden-Koch, Thomas C.; Dufresne, Robert J.; Mestre, Jose P.

2006-12-01

Coordination class theory is used to explain college students’ judgments about animated depictions of moving objects. diSessa’s coordination class theory models a “concept” as a complex knowledge system that can reliably determine a particular type of information in widely varying situations. In the experiment described here, fifty individually interviewed college students judged the realism of two sets of computer animations depicting balls rolling on a pair of tracks. The judgments of students from an introductory physics class were strongly affected by the number of balls depicted (one or two), but the judgments of students from an educational psychology class were not. Coordination analysis of interview transcripts supports the interpretation that physics students’ developing physics knowledge led them to consistently miss or ignore some observations that the other students consistently paid attention to. The analysis highlights the context sensitivity and potential fragility of coordination systems, and leads to the conclusion that students’ developing knowledge systems might not necessarily result in consistently improving performance.

Close encounters with DNA.

PubMed

Maffeo, C; Yoo, J; Comer, J; Wells, D B; Luan, B; Aksimentiev, A

2014-10-15

Over the past ten years, the all-atom molecular dynamics method has grown in the scale of both systems and processes amenable to it and in its ability to make quantitative predictions about the behavior of experimental systems. The field of computational DNA research is no exception, witnessing a dramatic increase in the size of systems simulated with atomic resolution, the duration of individual simulations and the realism of the simulation outcomes. In this topical review, we describe the hallmark physical properties of DNA from the perspective of all-atom simulations. We demonstrate the amazing ability of such simulations to reveal the microscopic physical origins of experimentally observed phenomena. We also discuss the frustrating limitations associated with imperfections of present atomic force fields and inadequate sampling. The review is focused on the following four physical properties of DNA: effective electric charge, response to an external mechanical force, interaction with other DNA molecules and behavior in an external electric field.

EDITORIAL: Physics competitions Physics competitions

NASA Astrophysics Data System (ADS)

Jordens, H.; Mathelitsch, L.

2009-11-01

1. Physics competitions: aims and realizations One aim of physics competitions is to increase the interest of young students, primarily at upper secondary level, to physics and natural sciences in general. A competition has motivational aspects known usually from sports events or games—comparing one's own ability with others, of course with the desire to be better and to win. If competitions reach nationwide and even international levels, additional stimulation is created. Competitions provide greatest attraction to possible winners, to the group of gifted people in a particular field. This implies that science contests are excellent tools for the promotion of talented students. Traditional teaching has been shown to have problems in supporting this group of students. Very often teachers are overstretched with the demands of teaching both low- and high-level students. Extracurricular activities are therefore a good chance to relieve the teacher, and to give talented students the opportunity for appropriate training and challenge. The competitions, however, have a broader impact and address more young people than one might guess from the statements above. Training courses and selection at school level give a larger group of students extra and, to some extent, complimentary education in physics. The degree of complexity of the tasks corresponds very often to the standards of the next level of education in the school system. Interestingly, many physics competitions have their origin in countries beyond the former Iron Curtain. They started as regional and national tournaments, were joined by neighbouring countries and have grown, in some cases, to events with participants from more than 80 countries. Although the features mentioned above are common to the different competitions, there are distinct differences between them [1]. The International Physics Olympiad (IPhO) is the oldest international physics competition for students at upper secondary level [2]. It dates

Reforming Military Command Arrangements: The Case of the Rapid Deployment Joint Task Force

DTIC Science & Technology

2011-03-01

protected. Organizational theory has identified actions that organizations normally pursue or avoid in order to increase—or at least preserve—their...thesis. See note 1 for details. 85 179. Jeffrey W. Taliaferro, Steven E. Lobell, and Norrin M. Ripsman, “Introduction: Neoclassical Realism, the State...and For- eign Policy,” in Steven E. Lobell, Norrin M. Ripsman and Jeffrey W. Taliaferro, eds., Neoclassical Realism, the State, and Foreign Poli- cy

Alternative Audio Solution to Enhance Immersion in Deployable Synthetic Environments

DTIC Science & Technology

2003-09-01

sense of presence. For example, the musical score of a movie increases the viewers’ emotional involvement in a cinematic feature. The character...photo-realistic way can make mental immersion difficult, because any flaw in the realism will spoil the effect [SHER 03].” One way to overcome spoiling...the visual realism is to reinforce visual clues with those from other modalities. 3. Aural Modality a. General Aural displays can be

Supporting Flight Control for UAV-Assisted Wilderness Search and Rescue Through Human Centered Interface Design

DTIC Science & Technology

2007-12-01

have found that increased realism typically makes a more impressive looking interface, but not always a more effective interface [53]. Some display...intended positions. Other, more cinematic meth- ods may look more impressive, but looking better is not necessarily more effective at supporting... realism : Misplaced faith in realis- tic displays. Ergonomics in Design: Magazine of Human Factors Applications, 13(3):6–13, 2005. [54] H. S. Smallman, M. St

Translations of JEN-MIN JIH-PAO Articles on Sociological and Economic Subjects

DTIC Science & Technology

1960-06-23

atmosphere filled, with fiery enthusiasm and the spirit of realism . kchie ver/ients At fcributabie_to_Poli^ios^SBjirning Taking for example the...but also gradually achieved good -quality. The stage play is different from the cinematic film. At the beginning of its performance, there might...forward the combination of revolutionary realism with revolutionary romaticism, &t-<x this is a creative method’which is in keeping with the spirt

USSR Report: Political and Sociological Affairs, No. 1478.

DTIC Science & Technology

1983-11-18

June (1983) Plenum of the CPSU Central Committee stressed the important role which the party attributes to literature and the art of socialist realism ...appearances they proudly speak of the high calling of literature and art of Socialist Realism , expose with publicistic and artis- tic force the...documentary films on the farm. However, cinematic practice also has its problems. Sometimes films are screened for which absence of ideals, banality

Virtual Manufacturing (la Fabrication virtuelle)

DTIC Science & Technology

1998-05-01

with moving parts and subassemblies, • verification of product subcomponents and systems operations through kinematics studies, and • realism ...dimensions, parts moved in mechanism based directions, and realism of interaction is increased through use of sound, touch and other parameters. For the...direct converters from CAD systems. A simple cinematic package is also high on the requirement to be able to simulate motions as well as an interface to

Complex systems: physics beyond physics

NASA Astrophysics Data System (ADS)

Holovatch, Yurij; Kenna, Ralph; Thurner, Stefan

2017-03-01

Complex systems are characterised by specific time-dependent interactions among their many constituents. As a consequence they often manifest rich, non-trivial and unexpected behaviour. Examples arise both in the physical and non-physical worlds. The study of complex systems forms a new interdisciplinary research area that cuts across physics, biology, ecology, economics, sociology, and the humanities. In this paper we review the essence of complex systems from a physicists' point of view, and try to clarify what makes them conceptually different from systems that are traditionally studied in physics. Our goal is to demonstrate how the dynamics of such systems may be conceptualised in quantitative and predictive terms by extending notions from statistical physics and how they can often be captured in a framework of co-evolving multiplex network structures. We mention three areas of complex-systems science that are currently studied extensively, the science of cities, dynamics of societies, and the representation of texts as evolutionary objects. We discuss why these areas form complex systems in the above sense. We argue that there exists plenty of new ground for physicists to explore and that methodical and conceptual progress is needed most.

Technology-enhanced simulation and pediatric education: a meta-analysis.

PubMed

Cheng, Adam; Lang, Tara R; Starr, Stephanie R; Pusic, Martin; Cook, David A

2014-05-01

Pediatrics has embraced technology-enhanced simulation (TES) as an educational modality, but its effectiveness for pediatric education remains unclear. The objective of this study was to describe the characteristics and evaluate the effectiveness of TES for pediatric education. This review adhered to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) standards. A systematic search of Medline, Embase, CINAHL, ERIC, Web of Science, Scopus, key journals, and previous review bibliographies through May 2011 and an updated Medline search through October 2013 were conducted. Original research articles in any language evaluating the use of TES for educating health care providers at any stage, where the content solely focuses on patients 18 years or younger, were selected. Reviewers working in duplicate abstracted information on learners, clinical topic, instructional design, study quality, and outcomes. We coded skills (simulated setting) separately for time and nontime measures and similarly classified patient care behaviors and patient effects. We identified 57 studies (3666 learners) using TES to teach pediatrics. Effect sizes (ESs) were pooled by using a random-effects model. Among studies comparing TES with no intervention, pooled ESs were large for outcomes of knowledge, nontime skills (eg, performance in simulated setting), behaviors with patients, and time to task completion (ES = 0.80-1.91). Studies comparing the use of high versus low physical realism simulators showed small to moderate effects favoring high physical realism (ES = 0.31-0.70). TES for pediatric education is associated with large ESs in comparison with no intervention. Future research should include comparative studies that identify optimal instructional methods and incorporate pediatric-specific issues into educational interventions. Copyright © 2014 by the American Academy of Pediatrics.

A Simple Method for Drawing Chiral Mononuclear Octahedral Metal Complexes

ERIC Educational Resources Information Center

Mohamadou, Aminou; Haudrechy, Arnaud

2008-01-01

Octahedral transition-metal complexes are involved in a number of reactions and octahedral coordination geometry, frequently observed for metallic centers, includes important topographical stereochemistry. Depending on the number and nature of different ligands, octahedral coordination units with at least two different monodentate ligands give…

Two-Dimensional Chirality in Three-Dimensional Chemistry.

ERIC Educational Resources Information Center

Wintner, Claude E.

1983-01-01

The concept of two-dimensional chirality is used to enhance students' understanding of three-dimensional stereochemistry. This chirality is used as a key to teaching/understanding such concepts as enaniotropism, diastereotopism, pseudoasymmetry, retention/inversion of configuration, and stereochemical results of addition to double bonds. (JN)

De novo asymmetric synthesis and biological analysis of the daumone pheromones in Caenorhabditis elegans and in the soybean cyst nematode Heterodera glycines

USDA-ARS?s Scientific Manuscript database

The de novo asymmetric total syntheses of daumone 1, daumone 2 and analogs are described. The key steps of our approach are the diastereoselective palladium catalyzed glycosylation reaction, the Noyori reduction of a acetylfuran and a propargyl ketone, which introduce the absolute stereochemistry of...

Rehabilitation of faulty kinetic determinations and misassigned glycoside hydrolase family of retaining mechanism ß-xylosidases

USDA-ARS?s Scientific Manuscript database

We obtained Cx1 from a commercial supplier, whose catalog listed it as a ß-xylosidase of glycoside hydrolase family 43. NMR experiments indicate retention of anomeric configuration in its reaction stereochemistry, opposing the assignment of GH43, which follows an inverting mechanism. Partial protein...

Reaction mechanisms: Stripping down SN2

NASA Astrophysics Data System (ADS)

Orr-Ewing, Andrew J.

2012-07-01

The mechanism of the SN2 reaction is fundamental to understanding and controlling the stereochemistry of organic reactions, but surrounding solvent molecules may complicate the textbook picture. Micro-solvation studies have now explored the stereochemical consequences of the presence of one or two solvent molecules.

Organic Lecture Demonstrations.

ERIC Educational Resources Information Center

Silversmith, Ernest F.

1988-01-01

Provides a listing of 35 demonstrations designed to generate interest in organic chemistry and help put points across. Topics include opening lecture; molecular structure and properties; halogenation; nucleophilic substitution, alkenes and dienes, stereochemistry, spectroscopy, alcohols and phenols, aldehydes and ketones; carboxylic acids, amines,…

Feminist Physics Education: Deconstructed Physics and Students' Multiple Subjectivities

NASA Astrophysics Data System (ADS)

Jammula, Diane Crenshaw

Physics is one of the least diverse sciences; in the U.S. in 2010, only 21% of bachelors degrees in physics were awarded to women, 2.5% to African Americans, and 4% to Hispanic Americans (AIP, 2012). Though physics education reform efforts supporting interactive engagement have doubled students' learning gains (Hake, 1998), gender and race gaps persist (Brewe et al., 2010; Kost, Pollock, & Finkelstein, 2009). When students' subjectivities align with presentations of physics, they are more likely to develop positive physics identities (Hughes, 2001). However, both traditional and reformed physics classrooms may present physics singularly as abstract, elite, and rational (Carlone, 2004). Drawing from feminist science, I argue that binaries including abstract / concrete, elite / accessible, and rational / emotional are hierarchal and gendered, raced and classed. The words on the left define conventional physics and are associated with middle class white masculinity, while the words on the right are associated with femininity or other, and are often missing or delegitimized in physics education, as are females and minorities. To conceptualize a feminist physics education, I deconstructed these binaries by including the words on the right as part of doing physics. I do not imply that women and men think differently, but that broadening notions of physics may allow a wider range of students to connect with the discipline. I used this conceptual framework to modify a popular reformed physics curriculum called Modeling Instruction (Hestenes, 1987). I taught this curriculum at an urban public college in an introductory physics course for non-science majors. Twenty-three students of diverse gender, race, ethnic, immigrant and class backgrounds enrolled. I conducted an ethnography of the classroom to learn how students negotiate their subjectivities to affiliate with or alienate from their perceptions of physics, and to understand how classroom experiences exacerbate or

Physical Activity Levels during Adventure-Physical Education Lessons

ERIC Educational Resources Information Center

Gehris, Jeffrey; Myers, Elizabeth; Whitaker, Robert

2012-01-01

Adventure-physical education has been proposed to promote adolescents' physical development, but little is known about physical activity levels during such lessons. Using the System for Observing Fitness Instruction Time, we observed students' (ages 11-14 years) physical activity levels in co-educational classes during 43 adventure-physical…

Introductory Physics Students' Physics and Mathematics Epistemologies

NASA Astrophysics Data System (ADS)

Scanlon, Erin M.

The purpose of this three study dissertation is to investigate why students are enrolled in introductory physics courses experience difficulties in being successful; one possible source of their difficulties is related to their epistemology. In order to investigate students' epistemologies about mathematics and physics, students were observed solving physics problems in groups during a laboratory course (study 1) and while solving physics and mathematics problems individually during office-hour sessions (study 2). The Epistemological Resources theoretical framework was employed (Hammer & Elby, 2002). Using emergent and a priori epistemological resource operationalizations (Jones, 2015), 25 distinct epistemological resources were identified in study 1. Differences in physics epistemological resource usage between students of varying academic background (as measured by their number of previously completed mathematics and science classes were identified. By employing an external (Jones, 2015) and internal (Scanlon, 2016) a priori epistemological resource coding scheme, a total of 17 distinct epistemological resources were identified in study 2. The data were sampled to compare the mathematics and physics epistemological resource usage of participants with consistent and inconsistent sign usage in an energy conservation physics problem in order to provide a meaningful context for discussion. Participants of the same sign usage group employed epistemological resources similarly. Conversely, participants in different groups had significantly different physics epistemological resource usage patterns. Finally, student epistemological resource usage patterns from the first two studies were compared to course outcomes in order to determine implications for practice (study 3). Educators must be aware of and address the epistemological underpinnings of students' difficulties in introductory physics courses.

Physical Activity and Health: Does Physical Education Matter?

ERIC Educational Resources Information Center

Pate, Russell R.; O'Neill, Jennifer R.; McIver, Kerry L.

2011-01-01

Physical education has been an institution in American schools since the late 19th century, and today almost all American children are exposed to physical education classes. It has often been claimed that physical education provides important benefits to public health. The purpose of this paper is to determine if physical education increases…

The History and Significance of the Incommensurability Thesis

NASA Astrophysics Data System (ADS)

Pearce, James Jacob

The incommensurability thesis (IT) maintains that there are no non-prejudicial means of choosing between competing theories in the empirical sciences. If true, IT would entail that natural science is a fundamentally subjective or irrational activity. Should this latter claim prove justifiable, then empirical science cannot be regarded as an organ of objective knowledge, and "scientific realism" is eo ipso false. I follow the origin of IT from its pre-history in Logical Positivism, through certain preliminary philosophical developments in the work of Karl Popper, W. V. O. Quine, Stephen Toulmin and N. R. Hanson, to the eventual formulation and introduction of IT by Thomas Kuhn and Paul Feyerabend. I then examine the rigorous criticism of IT by various philosophers since about 1964, and discuss different methods of objective theory comparison which have been advanced by such philosophers as Hilary Putnam, W. H. Newton-Smith, Michael Devitt, Hartry Field, Philip Kitcher and Howard Sankey. I conclude by arguing for two counterintuitive claims: (1) Even if true, IT fails to provide evidence against scientific realism. (2) In fact, the truth of IT actually furnishes evidence for a necessary condition for scientific realism, and hence evidence which can be construed as indirectly favorable to scientific realism.

Assessing physical function and physical activity in patients with CKD.

PubMed

Painter, Patricia; Marcus, Robin L

2013-05-01

Patients with CKD are characterized by low levels of physical functioning, which, along with low physical activity, predict poor outcomes in those treated with dialysis. The hallmark of clinical care in geriatric practice and geriatric research is the orientation to and assessment of physical function and functional limitations. Although there is increasing interest in physical function and physical activity in patients with CKD, the nephrology field has not focused on this aspect of care. This paper provides an in-depth review of the measurement of physical function and physical activity. It focuses on physiologic impairments and physical performance limitations (impaired mobility and functional limitations). The review is based on established frameworks of physical impairment and functional limitations that have guided research in physical function in the aging population. Definitions and measures for physiologic impairments, physical performance limitations, self-reported function, and physical activity are presented. On the basis of the information presented, recommendations for incorporating routine assessment of physical function and encouragement for physical activity in clinical care are provided.

Women in Physics.

ERIC Educational Resources Information Center

Roth, Laura M.; O'Fallon, Nancy M.

This booklet presents information about career opportunities for women in physics. Included are summaries of research areas in physics (optical physics, solid-state physics, materials science, nuclear physics, high-energy physics, astrophysics, cryogenics, plasma physics, biophysics, atmospheric physics) and differences between theory and…

Simulating 3D deformation using connected polygons

NASA Astrophysics Data System (ADS)

Tarigan, J. T.; Jaya, I.; Hardi, S. M.; Zamzami, E. M.

2018-03-01

In modern 3D application, interaction between user and the virtual world is one of an important factor to increase the realism. This interaction can be visualized in many forms; one of them is object deformation. There are many ways to simulate object deformation in virtual 3D world; each comes with different level of realism and performance. Our objective is to present a new method to simulate object deformation by using a graph-connected polygon. In this solution, each object contains multiple level of polygons in different level of volume. The proposed solution focusses on performance rather while maintaining the acceptable level of realism. In this paper, we present the design and implementation of our solution and show that this solution is usable in performance sensitive 3D application such as games and virtual reality.

Constructivism in Science and Science Education: A Philosophical Critique

NASA Astrophysics Data System (ADS)

Nola, Robert

This paper argues that constructivist science education works with an unsatisfactory account of knowledge which affects both its account of the nature of science and of science education. The paper begins with a brief survey of realism and anti-realism in science and the varieties of constructivism that can be found. In the second section the important conception of knowledge and teaching that Plato develops in the Meno is contrasted with constructivism. The section ends with an account of the contribution that Vico (as understood by constructivists), Kant and Piaget have made to constructivist doctrines. Section three is devoted to a critique of the theory of knowledge and the anti-realism of von Glaserfeld. The final section considers the connection, or lack of it, between the constructivist view of science and knowledge and the teaching of science.

Some Physics Not in the Physical Review.

ERIC Educational Resources Information Center

Varney, Robert N.

1982-01-01

Discusses how physics was done at the University of California at Berkeley in the 1930s, focusing on the faculty and their accomplishments, physics experiments, physics instruments/equipment (cyclotron and rhumbatron), and research problems and their solutions. Includes reminiscences about lectures on thermodynamics presented by Otto Stern during…

Promoting Physical Activity in Adapted Physical Education

ERIC Educational Resources Information Center

Yun, Joonkoo; Beamer, Jennifer

2018-01-01

The importance of physical activity has received considerable attention during the past decade. Physical education has been viewed as a cost-effective way to promote physical activity as a public health initiative. In fact, the Centers for Disease Control and Prevention recommends that a "substantial percentage" of students' overall…

Synthesis and properties of dithymidine phosphate analogues containing 3'-thiothymidine.

PubMed Central

Cosstick, R; Vyle, J S

1990-01-01

Dithymidine-3'-S-phosphorothioate (d(TspT)) has been prepared from a 5'-O-monomethoxytritylthymidine-3'-S-phosphorothioamidite (7) by activation with 5-(p-nitrophenyl)tetrazole in the presence of 3'-O-acetylthymidine. The resulting dinucleoside phosphorothioite is readily oxidised to the corresponding 3'-S-phosphorothioate using either tetrabutylammonium (TBA) periodate or TBA oxone and has been deprotected under standard conditions to yield d(TspT). This dithymidine phosphate analogue is comparatively resistant to hydrolysis by nuclease P1, but the P-S bond is readily cleaved by aqueous solutions of either iodine or silver nitrate. Dithymidine-3'-S-phosphorodithioate (d[Tsp(s)T]) was prepared in an analogous fashion using sulphur to oxidise the intermediate dinucleoside phosphorothioite. Absolute stereochemistry has been assigned to the diastereoisomers of d[Tsp(s)T] by comparing their physical and chemical properties to those of the dinucleoside phosphorothioates. PMID:2315041

Students' Views on Physical Development and Physical Self-Concept in Adventure-Physical Education

ERIC Educational Resources Information Center

Gehris, Jeffrey; Kress, Jeff; Swalm, Ricky

2010-01-01

This study investigated 10th-grade students' views concerning the physical effects of an adventure-physical education curriculum and the potential of such a curriculum to enhance components of a multidimensional model of physical self-concept. Semistructured interviews were used to obtain students' views and participant observations were conducted…

How should realism and hope be combined in physician-patient communication at the end of life? An online focus-group study among participants with and without a Muslim background.

PubMed

Oosterveld-Vlug, Mariska G; Francke, Anneke L; Pasman, H Roeline W; Onwuteaka-Philipsen, Bregje D

2017-06-01

Maintaining false hope may result in prolonged curative aggressive treatments until the very last stage of life. In this study, we sought to explore how people think that realistic and hopeful information should best be combined in physician-patient communications at the end of life. During a period of 15 days, participants of five online focus groups (OFGs) could log in onto a closed discussion site and offer responses to several topics. A variety of people participated: patients, older people, relatives, and healthcare professionals with and without a Muslim background. Participants with a Muslim background constituted a separate group, because previous research indicated that they might have distinct views on good end-of-life care and communication. Transcripts were analyzed following the principles of thematic analysis. Participants from all focus groups preferred that physicians provide realistic information in an empathic way, stating that the patient would never be left on his own and that withholding curative treatment was not equal to withholding care, explicitly asking how the patient could be helped during the time remaining, and involving other professionals in the care process and communications. As such, physicians could support patients' transition from "hope for a cure" to "hope for a good death." Muslims specified the way they wished to receive realistic information: first from a relative, and not by using the term "incurable illness," but rather by informing the patient that they had no remaining curative treatments available. Realism and hope are not necessarily mutually exclusive and can be combined when providing realistic information in a delicate and culturally sensitive way. This study provides suggestions on how physicians can do so. Communication skills training as well as anchoring knowledge of the diversity of cultural and religious views into physicians' education could improve end-of-life communication.

EDITORIAL: Physics competitions Physics competitions

NASA Astrophysics Data System (ADS)

Jordens, H.; Mathelitsch, L.

2011-07-01

International tests on competences, such as TIMSS or PISA, and knowledge of young students have revealed low average scores in many countries, often unexpectedly. One effective measure to increase the average standard of a population is to bring the last third of the group to a higher level. Therefore, many nations put some effort into this activity. This brings the danger that not enough attention is paid to students at the other end, those who are talented. Indeed, it is a very difficult task for a teacher to support the less able and at the same time challenge the gifted students, to lead them to the limits of their abilities and provide for a smooth transition to university study. Physics competitions have been proven to fulfil these last demands to a large degree, and therefore are an important additional and, to some extent, complementary tool for the promotion of talented students. This third special section on physics competitions in European Journal of Physics contains three papers, each dealing with a different form of science contest. The first continues the series of presentations of tasks performed at the International Young Physicists' Tournament, which was held in Vienna in 2011. First place went to the team from Singapore, and they have put their investigation on vertical oscillations of coupled magnets into written form (not required by the tournament, where an oral presentation and a defence and discussion are the central aspects). Their paper shows how rich in physics this problem is, and what level of solutions high-school students can already achieve. Sadly, those responsible for the organization of last year's International Physics Olympiad did not provide us with a report on this competition. This is unfortunate, since the Olympiad in Zagreb was very successful and, in particular, the experimental tasks were creative and demanding. Very similar to the aims and the execution of the Physics Olympiad is the International Olympiad on Astronomy

Configurable Semi-Autonomic Animated Animal Characters in Interactive Virtual Reality Applications

DTIC Science & Technology

2012-03-01

animal characters that can behave with a high degree of realism. The re- alism can be measured in two aspects. One is behavioral realism, or how real the...representations of animal characters in our training applications. This study is focused on animal behavior and animation for VR applications. A simple...of animal characters in our training applications. One such example is that dogs are used ex- tensively in security and law enforcement environments

Simultaneous Contrast: Examining the Use of American National Power

DTIC Science & Technology

2007-05-09

Assistance Command, Vietnam in 1962, or at the end of World War Two with the withdrawal of Japanese forces, or somewhere even earlier under French ...Half-Century Although the concepts of a middle way or some higher realism seemed to show the path as World War Two ended, it is only with the full...46Arthur S. Link, “The Higher Realism of Woodrow Wilson,” Journal of Presbytarian History, Vol 41 (March

Bat 21: A Case Study

DTIC Science & Technology

1990-04-02

whether or not the account represents the people, period and place with bona fide realism . The thematic review is a broad attempt to capture the...through with a simplified and believable narrative. A degree of realism is maintained that sustains the reader’s professional interest, even in light...ground instead of eleven and a half is clearly a cinematic device to close the film. The film does close with two exceptionally appropriate subtitles, both

USSR Report, Political and Sociological Affairs

DTIC Science & Technology

1986-09-23

travelers don’t skimp even on other advertised shows. This situation is common for cinematic forums of recent years. Every year this official competition...between the various groupings of artists in the twenties consisted in the forging and establishment of socialist realism , a process which ended with the...definitive victory of socialist realism and its heyday in the thirties." /9716 CSO: 1800/582 73 JPRS-UPS-86-046 23 September 1986 CULTURE

Development of a stereoselective and scalable process for the preparation of a methylcyclobutanol-pyridyl ether.

PubMed

Kuethe, Jeffrey T; Basu, Kallol; Orr, Robert K; Ashley, Eric; Poirier, Marc; Tan, Lushi

2018-02-15

The evolution of a scalable process for the preparation of methylcyclobutanol-pyridyl ether 1 is described. Key aspects of this development including careful control of the stereochemistry, elimination of chromatography, and application to kilogram-scale synthesis are addressed. Copyright © 2017 Elsevier Ltd. All rights reserved.

NMR spectra of 3β-hydroxy-5α-cholane derivatives, zymosterol synthesis intermediates

NASA Astrophysics Data System (ADS)

Baranovsky, A. V.; Bolotin, A. A.; Kiselev, V. P.

2011-05-01

Proton and carbon resonances in NMR spectra of a number of derivatives of 3β-hydroxy-5α-cholanes, zymosterol synthesis intermediates, have been completely assigned using 2D NMR spectroscopy methods. The stereochemistry of the chiral centers and the structures of the molecules have been confirmed.

Solvent effects on the relative stability of radicals derived from artemisinin: DFT study using the PCM/COSMO approach

NASA Astrophysics Data System (ADS)

Araujo, M. T. De; Carneiro, J. W. De M.; Taranto, A. G.

The PCM/COSMO approach was employed to calculate the relative stability of radicals derived from the antimalarial artemisinin. The calculations were performed in polar (water) and apolar (THF) solvent at the density functional level [B3LYP/6-31g(d)]. Relative stabilities were calculated by means of isodesmic equations using artemisinin as reference. Replacement of oxygen atoms by CH2 unities was found to decrease the relative stability of the anionic radical intermediates. The degree of destabilization is reduced in the presence of solvent, being less in water than in THF. The dipole moment and the corresponding solvation free energies of these species modulate this effect. Derivatives with inverted stereochemistry are more stable than those with the artemisinin-like stereochemistry, although the solvent attenuates this stabilization effect. As was found in the in vacuo calculations, the radicals centered on carbon are always more stable than the corresponding radicals centered on oxygen.

Photochemical activity of a key donor-acceptor complex can drive stereoselective catalytic α-alkylation of aldehydes.

PubMed

Arceo, Elena; Jurberg, Igor D; Alvarez-Fernández, Ana; Melchiorre, Paolo

2013-09-01

Asymmetric catalytic variants of sunlight-driven photochemical processes hold extraordinary potential for the sustainable preparation of chiral molecules. However, the involvement of short-lived electronically excited states inherent to any photochemical reaction makes it challenging for a chiral catalyst to dictate the stereochemistry of the products. Here, we report that readily available chiral organic catalysts, with well-known utility in thermal asymmetric processes, can also confer a high level of stereocontrol in synthetically relevant intermolecular carbon-carbon bond-forming reactions driven by visible light. A unique mechanism of catalysis is proposed, wherein the catalyst is involved actively in both the photochemical activation of the substrates (by inducing the transient formation of chiral electron donor-acceptor complexes) and the stereoselectivity-defining event. We use this approach to enable transformations that are extremely difficult under thermal conditions, such as the asymmetric α-alkylation of aldehydes with alkyl halides, the formation of all-carbon quaternary stereocentres and the control of remote stereochemistry.

Carbocation/Polyol Systems as Efficient Organic Catalysts for the Preparation of Cyclic Carbonates.

PubMed

Rulev, Yuri A; Gugkaeva, Zalina T; Lokutova, Anastasia V; Maleev, Victor I; Peregudov, Alexander S; Wu, Xiao; North, Michael; Belokon, Yuri N

2017-03-22

Carbocation/polyol systems are shown to be highly efficient catalysts for the synthesis of cyclic carbonates from epoxides and carbon dioxide at 50 °C and 5 MPa CO 2 pressure. The best activity was shown by the combination of crystal violet and 1,1'-bi-2-naphthol (BINOL), which could be recycled five times with no loss of activity. The presence of specific interactions between the amino groups of the carbocation and the hydroxyl protons was confirmed by NMR experiments. The Job plots for the crystal violet iodide/BINOL and brilliant green iodide/BINOL systems showed that the catalytic systems consist of one molecule of the carbocation and one molecule of BINOL. Mechanistic studies using a deuterated epoxide indicate that there was some loss of epoxide stereochemistry during the reaction, but predominant retention of stereochemistry is observed. On this basis, a catalytic cycle is proposed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structural studies of naturally occurring toxicogenic compounds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Springer, J. P.

1977-10-01

The paralytic shellfish poison (PSP), saxitoxin, is a neurotoxin isolated from Alaska butter clams (Saxidomus giganteus), mussels (Mytilus californianus) and axenic cultures of the dinoflagellate Gonyaulax catenella. The structure of saxitoxin has been determined through the use of single crystal X-ray diffraction. It possesses a unique tricyclic arrangement of atoms containing two guanidinium moieties and also a hydrated ketone. The relative stereochemistry is presented as well as the absolute configuration. The chemical constitution of a tremorgenic metabolite, paxilline, isolated from extracts of the fungus Penicillium paxilli Bainier has been determined. Paxilline represents a previously unreported class of natural compounds formedmore » by the combination of tryptophan and mevalonate subunits. The complete stereostructure of two other fungal metabolites, paspaline and paspalicine, closely related to paxilline but isolated from Claviceps paspali Stammes have also been determined and are presented. The stereochemistries of paxilline, paspaline and paspalicine are identical at corresponding chiral centers.« less

Relative stability of radicals derived from artemisinin: A semiempirical and DFT study

NASA Astrophysics Data System (ADS)

Arantes, C.; de Araujo, M. T.; Taranto, A. G.; de M. Carneiro, J. W.

The semiempirical AM1 and PM3 methods, as well as the density functional (DFT/B3LYP) approach using the 6-31g(d) basis set, were employed to calculate the relative stability of intermediate radicals derived from artemisinin, a sesquiterpene lactone having an endoperoxide bridge that is essential for its antimalarial activity. The compounds studied have their nonperoxidic oxygen atom of the trioxane ring and/or the carbonyl group replaced by a CH2 unit. Relative stabilities were calculated by means of isodesmic equations using artemisinin as reference. It was found that replacement of oxygen atoms decreases the relative stability of the anionic radical intermediates. In contrast, for compounds with inverted stereochemistry the intermediate radicals were found to be more stable than those with the artemisinin-like stereochemistry. These relative stabilities may modulate the antimalarial potency. Radicals centered on carbon are always more stable than the corresponding radicals centered on oxygen.

Radiation Oncology Physics and Medical Physics Education

NASA Astrophysics Data System (ADS)

Bourland, Dan

2011-10-01

Medical physics, an applied field of physics, is the applications of physics in medicine. Medical physicists are essential professionals in contemporary healthcare, contributing primarily to the diagnosis and treatment of diseases through numerous inventions, advances, and improvements in medical imaging and cancer treatment. Clinical service, research, and teaching by medical physicists benefits thousands of patients and other individuals every day. This talk will cover three main topics. First, exciting current research and development areas in the medical physics sub-specialty of radiation oncology physics will be described, including advanced oncology imaging for treatment simulation, image-guided radiation therapy, and biologically-optimized radiation treatment. Challenges in patient safety in high-technology radiation treatments will be briefly reviewed. Second, the educational path to becoming a medical physicist will be reviewed, including undergraduate foundations, graduate training, residency, board certification, and career opportunities. Third, I will introduce the American Association of Physicists in Medicine (AAPM), which is the professional society that represents, advocates, and advances the field of medical physics (www.aapm.org).

Looking forward, not back: Supporting structuralism in the present.

PubMed

McKenzie, Kerry

2016-10-01

The view that the fundamental kind properties are intrinsic properties enjoys reflexive endorsement by most metaphysicians of science. But ontic structural realists deny that there are any fundamental intrinsic properties at all. Given that structuralists distrust intuition as a guide to truth, and given that we currently lack a fundamental physical theory that we could consult instead to order settle the issue, it might seem as if there is simply nowhere for this debate to go at present. However, I will argue that there exists an as-yet untapped resource for arguing for ontic structuralism - namely, the way that fundamentality is conceptualized in our most fundamental physical frameworks. By arguing that physical objects must be subject to the 'Goldilock's principle' if they are to count as fundamental at all, I argue that we can no longer view the majority of properties defining them as intrinsic. As such, ontic structural realism can be regarded as the most promising metaphysics for fundamental physics, and that this is so even though we do not yet claim to know precisely what that fundamental physics is. Copyright © 2016 Elsevier Ltd. All rights reserved.

Perceived physical competence towards physical activity, and motivation and enjoyment in physical education as longitudinal predictors of adolescents' self-reported physical activity.

PubMed

Timo, Jaakkola; Sami, Yli-Piipari; Anthony, Watt; Jarmo, Liukkonen

2016-09-01

The aim of the study was to investigate if adolescents' perceived physical competence towards physical activity (PA), and autonomous motivation and enjoyment in physical education (PE) during early adolescence can predict amount and intensity of self-reported physical activity six years later. This study utilized a 6-year longitudinal data set collected within Finnish school settings. Students responded to questionnaires measuring their perceived physical competence towards physical activity, and autonomous motivation and enjoyment in PE during their first year at middle school (Grade 7), and their PA engagement during their last year in high school (Grade 12). A sample of 333 students (200 girls, 133 boys; M age=12.41, years, SD=.27) participated in the study. Perceived physical competence in physical activity was assessed by the sport competence dimension of the Physical Self-Perception Profile, autonomous motivation in PE was assessed by the Sport Motivation Scale and enjoyment in PE by the Sport Enjoyment Scale. Students' self-reported metabolic equivalent (MET) and PA intensity (light [LPA], moderate [MPA], vigorous [VPA]) was calculated from the short form of International Physical Activity Questionnaire. Perceived physical competence towards physical activity significantly predicted total METs (β=.28), MPA (β=.18) and VPA (β=.29) six years later. Autonomous motivation and enjoyment in PE at Grade 7, however, were not significant predictors of later PA. The results of this study support the proposition that self-perception of an individual's abilities arising from interactions with the environment related to PA during early puberty has an influential effect on later PA behaviour. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Standard Model of Particle Physics--a health physics perspective.

PubMed

Bevelacqua, J J

2010-11-01

The Standard Model of Particle Physics is reviewed with an emphasis on its relationship to the physics supporting the health physics profession. Concepts important to health physics are emphasized and specific applications are presented. The capability of the Standard Model to provide health physics relevant information is illustrated with application of conservation laws to neutron and muon decay and in the calculation of the neutron mean lifetime.

The relationship between physical activity and physical self-esteem in adolescents: the role of physical fitness indices.

PubMed

Haugen, Tommy; Ommundsen, Yngvar; Seiler, Stephen

2013-02-01

The aim of this study was to investigate if physical fitness (strength/power, endurance, flexibility and coordination) mediates the cross-sectional relationship between physical activity and physical self-perception (athletic competence and physical appearance) in a sample of 15-year old adolescents. We wanted to investigate the relative strength of each indirect effect. The present data are taken from two waves of a larger data collection for the project "Youth in Balance", and was collected in the autumn of 2005 (N = 1207) and 2008 (N = 632). A total of 1839 students (889 girls and 950 boys) from 12 schools in Kristiansand took part. A bias-corrected bootstrapping technique was used to examine indirect effects. Results revealed that cardiovascular endurance, lower-body strength/power, and upper-body strength stood out as unique mediators in the relationship between physical activity and athletic competence in both genders. Furthermore, there was an indirect effect of physical activity on physical appearance through physical strength/power and flexibility in males. No indirect effects of physical activity on physical appearance through actual physical fitness indices were detected in females.

Physics and Physics Education at Clarion University

NASA Astrophysics Data System (ADS)

Aravind, Vasudeva

Clarion University is located in the rolling hills of western Pennsylvania. We are a primarily undergraduate public institution serving about 6000 students. We graduate students who take different career paths, one of them being teaching physics at high schools. Since educating teachers of tomorrow requires us to introduce currently trending, research proven pedagogical methods, we incorporate several aspects of physics pedagogies such as peer instruction, flipped classroom and hands on experimentation in a studio physics lab format. In this talk, I discuss some of our projects on physics education, and seek to find potential collaborators interested in working along similar lines.

Physics through the 1990s: Nuclear physics

NASA Technical Reports Server (NTRS)

1986-01-01

The volume begins with a non-mathematical introduction to nuclear physics. A description of the major advances in the field follows, with chapters on nuclear structure and dynamics, fundamental forces in the nucleus, and nuclei under extreme conditions of temperature, density, and spin. Impacts of nuclear physics on astrophysics and the scientific and societal benefits of nuclear physics are then discussed. Another section deals with scientific frontiers, describing research into the realm of the quark-gluon plasma; the changing description of nuclear matter, specifically the use of the quark model; and the implications of the standard model and grand unified theories of elementary-particle physics; and finishes with recommendations and priorities for nuclear physics research facilities, instrumentation, accelerators, theory, education, and data bases. Appended are a list of national accelerator facilities, a list of reviewers, a bibliography, and a glossary.

Physics through the 1990s: Condensed-matter physics

NASA Technical Reports Server (NTRS)

1986-01-01

The volume presents the current status of condensed-matter physics from developments since the 1970s to opportunities in the 1990s. Topics include electronic structure, vibrational properties, critical phenomena and phase transitions, magnetism, semiconductors, defects and diffusion, surfaces and interfaces, low-temperature physics, liquid-state physics, polymers, nonlinear dynamics, instabilities, and chaos. Appendices cover the connections between condensed-matter physics and applications of national interest, new experimental techniques and materials, laser spectroscopy, and national facilities for condensed-matter physics research. The needs of the research community regarding support for individual researchers and for national facilities are presented, as are recommendations for improved government-academic-industrial relations.

24 CFR 965.601 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Physical condition standards; physical inspection requirements. 965.601 Section 965.601 Housing and Urban Development REGULATIONS... Physical Condition Standards and Physical Inspection Requirements § 965.601 Physical condition standards...

24 CFR 965.601 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Physical condition standards; physical inspection requirements. 965.601 Section 965.601 Housing and Urban Development REGULATIONS... Physical Condition Standards and Physical Inspection Requirements § 965.601 Physical condition standards...

24 CFR 965.601 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Physical condition standards; physical inspection requirements. 965.601 Section 965.601 Housing and Urban Development Regulations... Physical Condition Standards and Physical Inspection Requirements § 965.601 Physical condition standards...

24 CFR 965.601 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Physical condition standards; physical inspection requirements. 965.601 Section 965.601 Housing and Urban Development REGULATIONS... Physical Condition Standards and Physical Inspection Requirements § 965.601 Physical condition standards...

24 CFR 965.601 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Physical condition standards; physical inspection requirements. 965.601 Section 965.601 Housing and Urban Development REGULATIONS... Physical Condition Standards and Physical Inspection Requirements § 965.601 Physical condition standards...

Physics through the 1990s: Atomic, molecular and optical physics

NASA Technical Reports Server (NTRS)

1986-01-01

The volume presents a program of research initiatives in atomic, molecular, and optical physics. The current state of atomic, molecular, and optical physics in the US is examined with respect to demographics, education patterns, applications, and the US economy. Recommendations are made for each field, with discussions of their histories and the relevance of the research to government agencies. The section on atomic physics includes atomic theory, structure, and dynamics; accelerator-based atomic physics; and large facilities. The section on molecular physics includes spectroscopy, scattering theory and experiment, and the dynamics of chemical reactions. The section on optical physics discusses lasers, laser spectroscopy, and quantum optics and coherence. A section elucidates interfaces between the three fields and astrophysics, condensed matter physics, surface science, plasma physics, atmospheric physics, and nuclear physics. Another section shows applications of the three fields in ultra-precise measurements, fusion, national security, materials, medicine, and other topics.

Visualizing Molecular Chirality in the Organic Chemistry Laboratory Using Cholesteric Liquid Crystals

ERIC Educational Resources Information Center

Popova, Maia; Bretz, Stacey Lowery; Hartley, C. Scott

2016-01-01

Although stereochemistry is an important topic in second-year undergraduate organic chemistry, there are limited options for laboratory activities that allow direct visualization of macroscopic chiral phenomena. A novel, guided-inquiry experiment was developed that allows students to explore chirality in the context of cholesteric liquid crystals.…

Conformation analysis of oligomeric flavanoids

Treesearch

Jan P. Steynberg; E. Vincent Brandt; Daneel Ferreira; Carin A. Helfer; Wayne L. Mattice; Dominika Gornik; Richard W. Hemingway

1995-01-01

The profisetinidins are the most important polyflavanoids of commerce, making up the major constituents of wattle and quebracho tannins. Within the dimeric profisetinidins, substantial complexity exists because of stereo-, regio, rotational and conformational isomers. Definition of the stereochemistry of the upper and lower flavan units, the location of the...

Multidimensional Physical Self-Concept of Athletes with Physical Disabilities

ERIC Educational Resources Information Center

Shapiro, Deborah R.; Martin, Jeffrey J.

2010-01-01

The purposes of this investigation were first to predict reported PA (physical activity) behavior and self-esteem using a multidimensional physical self-concept model and second to describe perceptions of multidimensional physical self-concept (e.g., strength, endurance, sport competence) among athletes with physical disabilities. Athletes (N =…

Predicting Physics Achievement: Attitude towards Physics, Self-Efficacy of Learning Physics, and Mathematics Achievement

ERIC Educational Resources Information Center

Kapucu, Serkan

2017-01-01

This study aims to explore the relationships among Turkish high school students' attitude towards physics, self-efficacy of learning physics, mathematics achievement, and physics achievement. To investigate the relationships, a unique questionnaire that identifies the attitude, self-efficacy and achievements were delivered to a total of 301 high…

Antibiotic resistance versus small molecules, the chemical evolution.

PubMed

Lee, V J; Hecker, S J

1999-11-01

Two discovery approaches directed to addressing the problem of increasing bacterial resistance are described. The first is a program to build activity against methicillin-resistant Staphylococcus aureus (MRSA) into the cephalosporin class of antibacterials, by enhancing affinity for PBP2a, the penicillin-binding protein responsible for this resistance. Through stepwise improvement in potency, human serum binding, solubility, and betalactamase stability, a stable of new compounds with excellent potential as anti-MRSA agents was realized. From this set was chosen MC-02, 479 (RWJ-54428), which is now undergoing extensive preclinical evaluation. The second approach explores the uridyl peptide family of antibiotics, inhibitors of bacterial translocase (mraY), whose members include the pacidamycins, mureidomycins, and napsamycins. Access to a diverse set of analogs by total synthesis was catalyzed by the discovery that hydrogenation of the 4'-exoenamidofuranosyl moiety causes no loss in biological activity. Indepth exploration of SAR required (1) establishment of the absolute stereochemistry of the central diaminobutyric acid (DABA) moiety and (2) determination of the stereochemistry of the 4'-substituent on the deoxyfuranose unit. The former was accomplished by comparison of DABA derived from degradation of a natural product pacidamycin with a sample synthesized from L-threonine. The biological activity of one member of a synthesized library of possible stereoisomers of the natural product established the absolute stereochemistry of the remaining centers. A variety of analogs of the natural product were prepared utilizing the synthetic methods developed, and their biological activities provide important insights into the specificity and spectrum of the antibiotic class. Copyright 1999 John Wiley & Sons, Inc. Med Res Rev, 19, No. 6, 521-542, 1999

Connecting Symbolic Integrals to Physical Meaning in Introductory Physics

NASA Astrophysics Data System (ADS)

Amos, Nathaniel R.

This dissertation presents a series of studies pertaining to introductory physics students' abilities to derive physical meaning from symbolic integrals (e.g., the integral of vdt) and their components, namely differentials and differential products (e.g., dt and vdt, respectively). Our studies focus on physical meaning in the form of interpretations (e.g., "the total displacement of an object") and units (e.g., "meters"). Our first pair of studies independently attempted to identify introductory-level mechanics students' common conceptual difficulties with and unproductive interpretations of physics integrals and their components, as well as to estimate the frequencies of these difficulties. Our results confirmed some previously-observed incorrect interpretations, such as the notion that differentials are physically meaningless; however, we also uncovered two new conceptualizations of differentials, the "rate" (differentials are "rates" or "derivatives") and "instantaneous value" (differentials are values of physical variables "at an instant") interpretations, which were exhibited by more than half of our participants at least once. Our next study used linear regression analysis to estimate the strengths of the inter-connections between the abilities to derive physical meaning from each of differentials, differential products, and integrals in both first- and second-semester, calculus-based introductory physics. As part of this study, we also developed a highly reliable, multiple choice assessment designed to measure students' abilities to connect symbolic differentials, differential products, and integrals with their physical interpretations and units. Findings from this study were consistent with statistical mediation via differential products. In particular, students' abilities to extract physical meaning from differentials were seen to be strongly related to their abilities to derive physical meaning from differential products, and similarly differential

TU-A-17A-02: In Memoriam of Ben Galkin: Virtual Tools for Validation of X-Ray Breast Imaging Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Myers, K; Bakic, P; Abbey, C

2014-06-15

This symposium will explore simulation methods for the preclinical evaluation of novel 3D and 4D x-ray breast imaging systems – the subject of AAPM taskgroup TG234. Given the complex design of modern imaging systems, simulations offer significant advantages over long and costly clinical studies in terms of reproducibility, reduced radiation exposures, a known reference standard, and the capability for studying patient and disease subpopulations through appropriate choice of simulation parameters. Our focus will be on testing the realism of software anthropomorphic phantoms and virtual clinical trials tools developed for the optimization and validation of breast imaging systems. The symposium willmore » review the stateof- the-science, as well as the advantages and limitations of various approaches to testing realism of phantoms and simulated breast images. Approaches based upon the visual assessment of synthetic breast images by expert observers will be contrasted with approaches based upon comparing statistical properties between synthetic and clinical images. The role of observer models in the assessment of realism will be considered. Finally, an industry perspective will be presented, summarizing the role and importance of virtual tools and simulation methods in product development. The challenges and conditions that must be satisfied in order for computational modeling and simulation to play a significantly increased role in the design and evaluation of novel breast imaging systems will be addressed. Learning Objectives: Review the state-of-the science in testing realism of software anthropomorphic phantoms and virtual clinical trials tools; Compare approaches based upon the visual assessment by expert observers vs. the analysis of statistical properties of synthetic images; Discuss the role of observer models in the assessment of realism; Summarize the industry perspective to virtual methods for breast imaging.« less

Physical and Social Contexts of Physical Activities Among Adolescent Girls

PubMed Central

Kuo, JoAnn; Schmitz, Kathryn H.; Evenson, Kelly R.; McKenzie, Thomas L.; Jobe, Jared B.; Rung, Ariane L.; Gittelsohn, Joel; Pate, Russell R.

2016-01-01

Background With limited opportunities for physical activity during school hours, it is important to understand the contexts of physical activities done outside of school time. Given the importance of physical and social aspects of environments, the purpose of this study was to describe where and with whom girls participate in physical activities outside of school. Methods Participants were 1925 sixth-grade girls in the Trial of Activity for Adolescent Girls (TAAG). At baseline, they completed a 3-day physical activity recall (3DPAR), reporting the main activity performed during 30-minute intervals and the physical and social contexts of physical activities. Results The most frequently reported physical activities done outside of school time were house chores, walking (for transportation or exercise), dance, basketball, playing with younger children, and running or jogging. The most common location for these activities was at home or in the neighborhood. With the exception of household chores, these activities were typically done with at least one other person. Conclusions Interventions that promote physical activities that can be done at or around home or developing supportive social networks for physical activity would be consistent with the current physical activity contexts of adolescent girls. PMID:19420391

Physics Matters: An Introduction to Conceptual Physics

NASA Astrophysics Data System (ADS)

Trefil, James; Hazen, Robert M.

2003-12-01

From amusement park rides to critical environmental issues such as energy generation-physics affects almost every aspect of our world. In PHYSICS MATTERS, James Trefil and Robert Hazen examine the fundamental physics principles at work behind the many practical applications that fuel our society and individual lives. Their goal is to promote a deeper understanding of how the great ideas of physics connect to form a much larger understanding of the universe in which we live. Highlights Helps readers build a general knowledge of key ideas in physics and their connection to technology and other areas of science. Promotes an appreciation of what science is, how scientific knowledge is developed, and how it differs from other intellectual activities. Examines modern technologies, including GPS, the Internet, and information technologies, as well as medical technologies, such as MRI, PET scans, CAT scans, and radioisotope tracers. Explores key issues facing the world today, such as global warning, nuclear waste, and government funding for research.

Death: Realism in Children's Books.

ERIC Educational Resources Information Center

Danielson, Kathy Everts

In the past, books for children treated death fearfully, morbidly, and didactically, but now children's literature treats death in a more realistic manner and is sensitive to its emotional aspects. Current theories suggest that children perceive death differently at various ages. G. P. Koocher (1973) used J. Piaget's cognitive stages as the basis…

Neutrino physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haxton, Wick C.; Holstein, Barry R.; Department of Physics and Astronomy, University of Massachusetts, Amherst, Massachusetts 01003

2000-01-01

The basic concepts of neutrino physics are presented at a level appropriate for integration into elementary courses on quantum mechanics and/or modern physics. (c) 2000 American Association of Physics Teachers.

Physical versus Virtual Manipulative Experimentation in Physics Learning

ERIC Educational Resources Information Center

Zacharia, Zacharias C.; Olympiou, Georgios

2011-01-01

The aim of this study was to investigate whether physical or virtual manipulative experimentation can differentiate physics learning. There were four experimental conditions, namely Physical Manipulative Experimentation (PME), Virtual Manipulative Experimentation (VME), and two sequential combinations of PME and VME, as well as a control condition…

Physically Fit or Physically Literate? How Children with Special Educational Needs Understand Physical Education

ERIC Educational Resources Information Center

Coates, Janine

2011-01-01

The role of physical literacy within physical education (PE) has become a widely debated topic in recent years. Its role in educating children about physicality through embodiment, skill acquisition and reading the environment is argued to be of great benefit to children. However, whether children understand the role of PE in the development of…

Sports physical

MedlinePlus

... this page: //medlineplus.gov/ency/patientinstructions/000673.htm Sports physical To use the sharing features on this ... or routine checkups. Why do you Need a Sports Physical? The sports physical is done to: Find ...

Conformational analysis of oligomeric flavanoids

Treesearch

Jan P. Steynberg; E. Vincent Brandt; Daneel Ferreira; Carin A. Helfer; Wayne L. Mattice; Dominika Gornik; Richard W. Hemingway

1995-01-01

The profisetinidins are the most important polyflavanoids of commerce, making up the major constituents of wattle and quebracho tannins. Even within the dimeric profisetinidins, substantial complexity exists because of stereo-, regio-, rotational and conformational isomers. Definition of the stereochemistry of the upper and lower flavan units, the location of the...

Expectations Regarding Aging, Physical Activity, and Physical Function in Older Adults

PubMed Central

Breda, Aili I.; Watts, Amber S.

2017-01-01

Objective: The present study examined how expectations regarding aging (ERA) influence physical activity participation and physical function. Method: We surveyed 148 older adults about their ERA (ERA-38), health-promoting lifestyles (HPLP-II), and self-rated health (RAND-36). We tested the mediating effect of physical activity on the relationships between ERA and physical function. Results: Positive expectations were associated with more engagement in physical activity (B = 0.016, p < .05) and better physical function (B = 0.521, p < .01). Physical activity mediated the relationship between ERA and physical function (B = 5.890, p < .01, indirect effect 0.092, CI = [0.015, 0.239]). Discussion: ERA play an important role in adoption of physically active lifestyles in older adults and may influence health outcomes, such as physical function. Future research should evaluate whether attempts to increase physical activity are more successful when modifications to ERA are also targeted. PMID:28491915

Promoting Lifelong Physical Activity through Quality Physical Education

ERIC Educational Resources Information Center

Lee, Amelia M.

2004-01-01

Despite the recognized health risks associated with physical inactivity, most Americans are not active enough to achieve health benefits, and many report no planned physical activity at all. The Surgeon General's report on physical activity and health and several research studies have provided evidence that most Americans do not exercise and are…

Sports Physicals

MedlinePlus

... Staying Safe Videos for Educators Search English Español Sports Physicals KidsHealth / For Teens / Sports Physicals What's in ... beginning of your sports season. What Is a Sports Physical? In the sports medicine field, the sports ...

Censored rainfall modelling for estimation of fine-scale extremes

NASA Astrophysics Data System (ADS)

Cross, David; Onof, Christian; Winter, Hugo; Bernardara, Pietro

2018-01-01

Reliable estimation of rainfall extremes is essential for drainage system design, flood mitigation, and risk quantification. However, traditional techniques lack physical realism and extrapolation can be highly uncertain. In this study, we improve the physical basis for short-duration extreme rainfall estimation by simulating the heavy portion of the rainfall record mechanistically using the Bartlett-Lewis rectangular pulse (BLRP) model. Mechanistic rainfall models have had a tendency to underestimate rainfall extremes at fine temporal scales. Despite this, the simple process representation of rectangular pulse models is appealing in the context of extreme rainfall estimation because it emulates the known phenomenology of rainfall generation. A censored approach to Bartlett-Lewis model calibration is proposed and performed for single-site rainfall from two gauges in the UK and Germany. Extreme rainfall estimation is performed for each gauge at the 5, 15, and 60 min resolutions, and considerations for censor selection discussed.

Physical self-concept and physical fitness in elderly individuals.

PubMed

Amesberger, G; Finkenzeller, T; Würth, S; Müller, E

2011-08-01

This investigation examined the relations between physical self-concept and physical fitness (endurance, balance, muscle strength, muscle power) for gaining knowledge about the interrelationship between subjective ratings and objective fitness scores in the elderly in three steps: (1) detecting correlations and changes in time, (2) clarifying the influence of gender, and (3) of a skiing intervention lasting 12 weeks. Physical self-concept was assessed using a modified version of the Physical Self-Concepts (PSK) scales (Stiller et al., 2004) reflecting three first-order factors (endurance, strength, general sportiness) and one second-order factor (global fitness). Objective fitness scores were obtained by VO(2 max), counter movement jump, concentric muscle strength, and static balance. The results reveal that elderly individuals' global physical self and general sportiness are mainly linked to VO(2 max) and concentric muscle strength. Global physical self is predicted by VO(2 max) in females and by physical strength (concentric muscle strength) in males, indicating gender differences. Over time, correlations between subjective ratings and objective fitness scores become stronger in the sense of convergent validity in the skiing intervention group, whereas convergent and divergent validity cannot be supported by data of the control group. In sum, physical self-concept is an important factor in the context of physical intervention programs in the elderly. © 2011 John Wiley & Sons A/S.

Predicting Decade-to-Century Climate Change: Prospects for Improving Models

NASA Technical Reports Server (NTRS)

Somerville, Richard C. J.

1999-01-01

Recent research has led to a greatly increased understanding of the uncertainties in today's climate models. In attempting to predict the climate of the 21st century, we must confront not only computer limitations on the affordable resolution of global models, but also a lack of physical realism in attempting to model key processes. Until we are able to incorporate adequate treatments of critical elements of the entire biogeophysical climate system, our models will remain subject to these uncertainties, and our scenarios of future climate change, both anthropogenic and natural, will not fully meet the requirements of either policymakers or the public. The areas of most-needed model improvements are thought to include air-sea exchanges, land surface processes, ice and snow physics, hydrologic cycle elements, and especially the role of aerosols and cloud-radiation interactions. Of these areas, cloud-radiation interactions are known to be responsible for much of the inter-model differences in sensitivity to greenhouse gases. Recently, we have diagnostically evaluated several current and proposed model cloud-radiation treatments against extensive field observations. Satellite remote sensing provides an indispensable component of the observational resources. Cloud-radiation parameterizations display a strong sensitivity to vertical resolution, and we find that vertical resolutions typically used in global models are far from convergence. We also find that newly developed advanced parameterization schemes with explicit cloud water budgets and interactive cloud radiative properties are potentially capable of matching observational data closely. However, it is difficult to evaluate the realism of model-produced fields of cloud extinction, cloud emittance, cloud liquid water content and effective cloud droplet radius until high-quality measurements of these quantities become more widely available. Thus, further progress will require a combination of theoretical and modeling

Tests of alternative quantum theories with neutrons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sponar, S.; Durstberger-Rennhofer, K.; Badurek, G.

2014-12-04

According to Bell’s theorem, every theory based on local realism is at variance with certain predictions of quantum mechanics. A theory that maintains realism but abandons reliance on locality, which has been proposed by Leggett, is incompatible with experimentally observable quantum correlations. In our experiment correlation measurements of spin-energy entangled single-neutrons violate a Leggett-type inequality by more than 7.6 standard deviations. The experimental data falsify the contextual realistic model and are fully in favor of quantum mechanics.

Physical Education and Physical Activity: A Historical Perspective

ERIC Educational Resources Information Center

Guedes, Claudia

2007-01-01

Although many recent studies have shown that the lack of physical activity is one of the major causes of obesity, diabetes, and cardiovascular disease among children and adolescents, few studies have shown the connection between the lack of physical education and the prevalence of a sedentary lifestyle. However, it is clear that physical education…

24 CFR 891.180 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Physical condition standards; physical inspection requirements. 891.180 Section 891.180 Housing and Urban Development REGULATIONS... DISABILITIES General Program Requirements § 891.180 Physical condition standards; physical inspection...

24 CFR 886.307 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Physical condition standards; physical inspection requirements. 886.307 Section 886.307 Housing and Urban Development REGULATIONS....307 Physical condition standards; physical inspection requirements. (a) General. Housing assisted...

24 CFR 886.307 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Physical condition standards; physical inspection requirements. 886.307 Section 886.307 Housing and Urban Development REGULATIONS....307 Physical condition standards; physical inspection requirements. (a) General. Housing assisted...

24 CFR 891.180 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Physical condition standards; physical inspection requirements. 891.180 Section 891.180 Housing and Urban Development REGULATIONS... DISABILITIES General Program Requirements § 891.180 Physical condition standards; physical inspection...

24 CFR 886.307 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Physical condition standards; physical inspection requirements. 886.307 Section 886.307 Housing and Urban Development Regulations....307 Physical condition standards; physical inspection requirements. (a) General. Housing assisted...

24 CFR 886.307 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Physical condition standards; physical inspection requirements. 886.307 Section 886.307 Housing and Urban Development REGULATIONS....307 Physical condition standards; physical inspection requirements. (a) General. Housing assisted...

24 CFR 891.180 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Physical condition standards; physical inspection requirements. 891.180 Section 891.180 Housing and Urban Development Regulations... DISABILITIES General Program Requirements § 891.180 Physical condition standards; physical inspection...

24 CFR 886.307 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Physical condition standards; physical inspection requirements. 886.307 Section 886.307 Housing and Urban Development REGULATIONS....307 Physical condition standards; physical inspection requirements. (a) General. Housing assisted...

24 CFR 891.180 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Physical condition standards; physical inspection requirements. 891.180 Section 891.180 Housing and Urban Development REGULATIONS... DISABILITIES General Program Requirements § 891.180 Physical condition standards; physical inspection...

24 CFR 891.180 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Physical condition standards; physical inspection requirements. 891.180 Section 891.180 Housing and Urban Development REGULATIONS... DISABILITIES General Program Requirements § 891.180 Physical condition standards; physical inspection...

Outside-school physical activity participation and motivation in physical education.

PubMed

Shen, Bo

2014-03-01

Experience in non-school contexts can shape and reshape students' motivation and mediate their learning in school. Outside-school physical activity may provide students with an extensive cognitive and affective foundation and influence their motivation in physical education. Although a trans-contextual effect of physical education has been explored, very little empirical research has examined the impact from outside-school context to physical education. Using self-determination theory and a hierarchical model of motivation, this study was designed to examine the association between participation in organized outside-school physical activity programmes and self-determination process in physical education. Participants included 545 9th graders (305 males and 240 females, age range = 14-16 years, mean age = 14.66 years) enrolled in required physical education classes in three suburban high schools in a large Midwest metropolitan area in the United States. Self-determination variables were measured using relevant instruments, and information on organized outside-school physical activity experiences was gathered in a survey. Structural equation modelling analyses were conducted. Students who participated in organized outside-school physical activity programmes displayed overall higher motivation; however, the strength of associations among the self-determination variables (i.e., pathways from perceived autonomy support to relatedness, from autonomy to competence, and from self-determined motivation to in-class physical activity engagement) was stronger for their non-participant counterparts. There are dynamic relationships between participation in organized outside-school physical activity programmes and self-determination process in physical education. Physical educators need to identify, appreciate, and instructionally address individual students' differences during teaching and learning. © 2012 The British Psychological Society.

Assessing physical activity using wearable monitors: measures of physical activity.

PubMed

Butte, Nancy F; Ekelund, Ulf; Westerterp, Klaas R

2012-01-01

Physical activity may be defined broadly as "all bodily actions produced by the contraction of skeletal muscle that increase energy expenditure above basal level." Physical activity is a complex construct that can be classified into major categories qualitatively, quantitatively, or contextually. The quantitative assessment of physical activity using wearable monitors is grounded in the measurement of energy expenditure. Six main categories of wearable monitors are currently available to investigators: pedometers, load transducers/foot-contact monitors, accelerometers, HR monitors, combined accelerometer and HR monitors, and multiple sensor systems. Currently available monitors are capable of measuring total physical activity as well as components of physical activity that play important roles in human health. The selection of wearable monitors for measuring physical activity will depend on the physical activity component of interest, study objectives, characteristics of the target population, and study feasibility in terms of cost and logistics. Future development of sensors and analytical techniques for assessing physical activity should focus on the dynamic ranges of sensors, comparability for sensor output across manufacturers, and the application of advanced modeling techniques to predict energy expenditure and classify physical activities. New approaches for qualitatively classifying physical activity should be validated using direct observation or recording. New sensors and methods for quantitatively assessing physical activity should be validated in laboratory and free-living populations using criterion methods of calorimetry or doubly labeled water.

Intensity and duration of physical efforts in Physical Education classes.

PubMed

Kremer, Marina Marques; Reichert, Felipe Fossati; Hallal, Pedro Curi

2012-04-01

To evaluate the intensity and duration of physical efforts in Physical Education classes in primary and secondary school. School-based cross-sectional study carried out by means of the observation of 218 Physical Education classes, including a total of 272 students (each one of the students was evaluated three times). The study was carried out in the city of Pelotas (Southern Brazil), between August and December 2009. In order to evaluate the intensity of the efforts, accelerometers were used and the following cut-off points were adopted (in counts per minute): sedentary activities (0-100), light activities (101-2,000), moderate (2,001-4,999), vigorous (5,000-7,999), and very vigorous activities (>8000). The mean duration of the classes was 35.6 minutes (SD 6.0). The mean proportion of time spent in moderate to vigorous physical activity was 32.7% (SD 25.2). Boys (44.1%) were involved significantly more in moderate to vigorous physical activity as compared to girls (21.0%; p<0.01). Students who practice physical activities outside the classes participated more in moderate to vigorous physical activity in the Physical Education classes. Besides the fact that Physical Education classes have a short duration, students practice moderate to vigorous physical activity during one third of the class, with a poor significant contribution to students' level of physical activity.

Increasing Physical Activity during the School Day through Physical Activity Classes: Implications for Physical Educators

ERIC Educational Resources Information Center

Adkins, Megan; Bice, Matt; Bartee, Todd; Heelan, Kate

2015-01-01

Across the nation schools are adopting health and wellness policies, specifically physical activity (PA) initiatives that aid healthy long-term lifestyles. Interest has been generated about the inclusion of physical activity classes to complement existing physical education classes. Furthermore, discussion has evolved as to if additional…

24 CFR 886.113 - Physical condition standard; physical inspection requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Physical condition standard; physical inspection requirements. 886.113 Section 886.113 Housing and Urban Development Regulations... § 886.113 Physical condition standard; physical inspection requirements. (a) General. Housing used in...

24 CFR 886.113 - Physical condition standard; physical inspection requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Physical condition standard; physical inspection requirements. 886.113 Section 886.113 Housing and Urban Development REGULATIONS... § 886.113 Physical condition standard; physical inspection requirements. (a) General. Housing used in...

24 CFR 886.113 - Physical condition standard; physical inspection requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Physical condition standard; physical inspection requirements. 886.113 Section 886.113 Housing and Urban Development REGULATIONS... § 886.113 Physical condition standard; physical inspection requirements. (a) General. Housing used in...

24 CFR 882.404 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Physical condition standards; physical inspection requirements. 882.404 Section 882.404 Housing and Urban Development Regulations... Procedures for Moderate Rehabilitation-Basic Policies § 882.404 Physical condition standards; physical...

24 CFR 882.404 - Physical condition standards; physical inspection requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Physical condition standards; physical inspection requirements. 882.404 Section 882.404 Housing and Urban Development REGULATIONS... Procedures for Moderate Rehabilitation-Basic Policies § 882.404 Physical condition standards; physical...